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Sample records for replication-related sister chromatid

  1. Sister chromatid cohesion and recombination in meiosis

    NARCIS (Netherlands)

    Heemst, van D.; Heyting, C.

    2000-01-01

    Sister chromatids are associated from their formation until their disjunction. Cohesion between sister chromatids is provided by protein complexes, of which some components are conserved across the kingdoms and between the mitotic and meiotic cell cycles. Sister chromatid cohesion is intimately link

  2. Sister chromatid segregation in meiosis II

    Science.gov (United States)

    Wassmann, Katja

    2013-01-01

    Meiotic divisions (meiosis I and II) are specialized cell divisions to generate haploid gametes. The first meiotic division with the separation of chromosomes is named reductional division. The second division, which takes place immediately after meiosis I without intervening S-phase, is equational, with the separation of sister chromatids, similar to mitosis. This meiotic segregation pattern requires the two-step removal of the cohesin complex holding sister chromatids together: cohesin is removed from chromosome arms that have been subjected to homologous recombination in meiosis I and from the centromere region in meiosis II. Cohesin in the centromere region is protected from removal in meiosis I, but this protection has to be removed—deprotected”—for sister chromatid segregation in meiosis II. Whereas the mechanisms of cohesin protection are quite well understood, the mechanisms of deprotection have been largely unknown until recently. In this review I summarize our current knowledge on cohesin deprotection. PMID:23574717

  3. Mechanics of Sister Chromatids studied with a Polymer Model English

    Science.gov (United States)

    Zhang, Yang; Isbaner, Sebastian; Heermann, Dieter

    2013-10-01

    Sister chromatid cohesion denotes the phenomenon that sister chromatids are initially attached to each other in mitosis to guarantee the error-free distribution into the daughter cells. Cohesion is mediated by binding proteins and only resolved after mitotic chromosome condensation is completed. However, the amount of attachement points required to maintain sister chromatid cohesion while still allowing proper chromosome condensation is not known yet. Additionally the impact of cohesion on the mechanical properties of chromosomes also poses an interesting problem. In this work we study the conformational and mechanical properties of sister chromatids by means of computer simulations. We model both protein-mediated cohesion between sister chromatids and chromosome condensation with a dynamic binding mechanisms. We show in a phase diagram that only specific link concentrations lead to connected and fully condensed chromatids that do not intermingle with each other nor separate due to entropic forces. Furthermore we show that dynamic bonding between chromatids decrease the Young's modulus compared to non-bonded chromatids.

  4. Mechanics of Sister Chromatids studied with a Polymer Model

    Directory of Open Access Journals (Sweden)

    Yang eZhang

    2013-10-01

    Full Text Available Sister chromatid cohesion denotes the phenomenon that sister chromatids are initially attached to each other in mitosis to guarantee the error-free distribution into the daughter cells. Cohesion is mediated by binding proteins and only resolved after mitotic chromosome condensation is completed. However, the amount of attachement points required to maintain sister chromatid cohesion while still allowing proper chromosome condensation is not known yet. Additionally the impact of cohesion on the mechanical properties of chromosomes also poses an interesting problem. In this work we study the conformational and mechanical properties of sister chromatids by means of computer simulations. We model both protein-mediated cohesion between sister chromatids and chromosome condensation with a dynamic binding mechanisms. We show in a phase diagram that only specific link concentrations lead to connected and fully condensed chromatids that do not intermingle with each other nor separate due to entropic forces. Furthermore we show that dynamic bonding between chromatids decrease the Young's modulus compared to non-bonded chromatids.

  5. Similar Sister Chromatid Arrangement in Mono- and Holocentric Plant Chromosomes.

    Science.gov (United States)

    Schubert, Veit; Zelkowski, Mateusz; Klemme, Sonja; Houben, Andreas

    2016-01-01

    Due to the X-shape formation at somatic metaphase, the arrangement of the sister chromatids is obvious in monocentric chromosomes. In contrast, the sister chromatids of holocentric chromosomes cannot be distinguished even at mitotic metaphase. To clarify their organization, we differentially labelled the sister chromatids of holocentric Luzula and monocentric rye chromosomes by incorporating the base analogue EdU during replication. Using super-resolution structured illumination microscopy (SIM) and 3D rendering, we found that holocentric sister chromatids attach to each other at their contact surfaces similar to those of monocentrics in prometaphase. We found that sister chromatid exchanges (SCEs) are distributed homogeneously along the whole holocentric chromosomes of Luzula, and that their occurrence is increased compared to monocentric rye chromosomes. The SCE frequency of supernumerary B chromosomes, present additionally to the essential A chromosome complement of rye, does not differ from that of A chromosomes. Based on these results, models of the sister chromatid arrangement in mono- and holocentric plant chromosomes are presented.

  6. Is chromatin remodeling required to build sister-chromatid cohesion?

    NARCIS (Netherlands)

    Riedel, Christian G; Gregan, Juraj; Gruber, Stephan; Nasmyth, Kim

    2004-01-01

    Chromosome segregation during mitosis and meiosis depends on the linkage of sister DNA molecules after replication. These links, known as sister-chromatid cohesion, are provided by a multi-subunit complex called cohesin. Recent papers suggest that chromatin-remodeling complexes also have a role in t

  7. Sister chromatid segregation in meiosis II: deprotection through phosphorylation.

    Science.gov (United States)

    Wassmann, Katja

    2013-05-01

    Meiotic divisions (meiosis I and II) are specialized cell divisions to generate haploid gametes. The first meiotic division with the separation of chromosomes is named reductional division. The second division, which takes place immediately after meiosis I without intervening S-phase, is equational, with the separation of sister chromatids, similar to mitosis. This meiotic segregation pattern requires the two-step removal of the cohesin complex holding sister chromatids together: cohesin is removed from chromosome arms that have been subjected to homologous recombination in meiosis I and from the centromere region in meiosis II. Cohesin in the centromere region is protected from removal in meiosis I, but this protection has to be removed--deprotected--for sister chromatid segregation in meiosis II. Whereas the mechanisms of cohesin protection are quite well understood, the mechanisms of deprotection have been largely unknown until recently. In this review I summarize our current knowledge on cohesin deprotection.

  8. Precocious Sister Chromatid Separation (PSCS) in Cornelia de Lange Syndrome

    Science.gov (United States)

    Kaur, Maninder; DeScipio, Cheryl; McCallum, Jennifer; Yaeger, Dinah; Devoto, Marcella; Jackson, Laird G.; Spinner, Nancy B.; Krantz, Ian D.

    2009-01-01

    The Cornelia de Lange syndrome (CdLS) (OMIM# 122470) is a dominantly inherited multisystem developmental disorder. The phenotype consists of characteristic facial features, hirsutism, abnormalities of the upper extremities ranging from subtle changes in the phalanges and metacarpal bones to oligodactyly and phocomelia, gastroesophageal dysfunction, growth retardation, and neurodevelopmental delay. Prevalence is estimated to be as high as 1 in 10,000. Recently, mutations in NIPBL were identified in sporadic and familial CdLS cases. To date, mutations in this gene have been identified in over 45% of individuals with CdLS. NIPBL is the human homolog of the Drosophila Nipped-B gene. Although its function in mammalian systems has not yet been elucidated, sequence homologs of Nipped-B in yeast (Scc2 and Mis4) are required for sister chromatid cohesion during mitosis, and a similar role was recently demonstrated for Nipped-B in Drosophila. In order to evaluate NIPBL role in sister chromatid cohesion in humans, metaphase spreads on 90 probands (40 NIPBL mutation positive and 50 NIPBL mutation negative) with CdLS were evaluated for evidence of precocious sister chromatid separation (PSCS). We screened 50 metaphases from each proband and found evidence of PSCS in 41% (compared to 9% in control samples). These studies indicate that NIPBL may play a role in sister chromatid cohesion in humans as has been reported for its homologs in Drosophila and yeast. PMID:16100726

  9. Meiotic sister chromatid cohesion and recombination in two filamentous fungi

    NARCIS (Netherlands)

    Heemst, van D.

    2000-01-01

    Homologous recombination and sister chromatid cohesion play important roles in the maintenance of genome integrity and the fidelity of chromosome segregation in mitosis and meiosis. Within the living cell, the integrity of the DNA is threatened by various factors that cause DNA-lesions, of which DNA

  10. Cohesin SMC1 beta is required for meiotic chromosome dynamics, sister chromatid cohesion and DNA recombination

    NARCIS (Netherlands)

    Revenkova, E.; Eijpe, M.; Heyting, C.; Hodges, C.A.; Hunt, P.A.; Liebe, B.; Scherthan, H.; Jessberger, R.

    2004-01-01

    Sister chromatid cohesion ensures the faithful segregation of chromosomes in mitosis and in both meiotic divisions1, 2, 3, 4. Meiosis-specific components of the cohesin complex, including the recently described SMC1 isoform SMC15, were suggested to be required for meiotic sister chromatid cohesion a

  11. Sister chromatid tension and the spindle assembly checkpoint.

    Science.gov (United States)

    Nezi, Luigi; Musacchio, Andrea

    2009-12-01

    The spindle assembly checkpoint (SAC) is a feedback control system that monitors the state of kinetochore/microtubule attachment during mitosis and halts cell cycle progression until all chromosomes are properly aligned at the metaphase plate. The state of chromosome-microtubule attachment is implicated as a crucial factor in the checkpoint response. On the contrary, lack of tension in the centromere-kinetochore region of sister chromatids has been shown to regulate a pathway of correction of undesired chromosome-microtubule connections, while the presence of tension is believed to promote the stabilization of attachments. We discuss how tension-sensitive phenomena, such as attachment correction and stabilization, relate to the SAC and we speculate on the existence of a single pathway linking error correction and SAC activation.

  12. Sister chromatid exchange in Polish White improved goats (Capra hircus).

    Science.gov (United States)

    Wójcik, Ewa; Smalec, Elzbieta

    2012-01-01

    The study was aimed at evaluating the frequency of spontaneous sister chromatid exchange in Polish White Improved goats (Capra hircus). The mean number of SCEs/cell was 2.73 +/- 1.84. The effect of sex and age on SCE incidence was also investigated. No statistically significant differences in the number of SCEs/cell were observed between the males and females. On the other hand, age was found to significantly influence SCE frequency. A lower SCE frequency was observed in younger goats. A positive correlation between chromosome length and SCE number was identified. The longer the chromosome, the more exchanges occurred. The highest number of SCEs was observed in the interstitial region, the lowest in the distal area.

  13. Sororin actively maintains sister chromatid cohesion.

    Science.gov (United States)

    Ladurner, Rene; Kreidl, Emanuel; Ivanov, Miroslav P; Ekker, Heinz; Idarraga-Amado, Maria Helena; Busslinger, Georg A; Wutz, Gordana; Cisneros, David A; Peters, Jan-Michael

    2016-03-15

    Cohesion between sister chromatids is established during DNA replication but needs to be maintained to enable proper chromosome-spindle attachments in mitosis or meiosis. Cohesion is mediated by cohesin, but also depends on cohesin acetylation and sororin. Sororin contributes to cohesion by stabilizing cohesin on DNA. Sororin achieves this by inhibiting WAPL, which otherwise releases cohesin from DNA and destroys cohesion. Here we describe mouse models which enable the controlled depletion of sororin by gene deletion or auxin-induced degradation. We show that sororin is essential for embryonic development, cohesion maintenance, and proper chromosome segregation. We further show that the acetyltransferases ESCO1 and ESCO2 are essential for stabilizing cohesin on chromatin, that their only function in this process is to acetylate cohesin's SMC3 subunit, and that DNA replication is also required for stable cohesin-chromatin interactions. Unexpectedly, we find that sororin interacts dynamically with the cohesin complexes it stabilizes. This implies that sororin recruitment to cohesin does not depend on the DNA replication machinery or process itself, but on a property that cohesin acquires during cohesion establishment.

  14. Sister chromatid gene conversion is a prominent double-strand break repair pathway in mammalian cells

    OpenAIRE

    Johnson, Roger D.; Jasin, Maria

    2000-01-01

    In mammalian cells, repair of DNA double-strand breaks (DSBs) occurs by both homologous and non-homologous mechanisms. By definition, homologous recombination requires a template with sufficient sequence identity to the damaged molecule in order to direct repair. We now show that the sister chromatid acts as a repair template in a substantial proportion of DSB repair events. The outcome of sister chromatid repair is primarily gene conversion unassociated with reciprocal exchange. This contras...

  15. Solution Radioactivated by Hadron Radiation Can Increase Sister Chromatid Exchanges.

    Science.gov (United States)

    Maeda, Junko; Yurkon, Charles R; Fujii, Yoshihiro; Fujisawa, Hiroshi; Kato, Sayaka; Brents, Colleen A; Uesaka, Mitsuru; Fujimori, Akira; Kitamura, Hisashi; Kato, Takamitsu A

    2015-01-01

    When energetic particles irradiate matter, it becomes activated by nuclear reactions. Radioactivation induced cellular effects are not clearly understood, but it could be a part of bystander effects. This investigation is aimed at understanding the biological effects from radioactivation in solution induced by hadron radiation. Water or phosphate buffered saline was activated by being exposed to hadron radiation including protons, carbon- and iron-ions. 1 mL of radioactivated solution was transferred to flasks with Chinese hamster ovary (CHO) cells cultured in 5 mL of complete media. The induction of sister chromatid exchanges (SCE) was used to observe any increase in DNA damage responses. The energy spectrum and the half-lives of the radioactivation were analyzed by NaI scintillation detector in order to identify generated radionuclides. In the radioactivated solution, 511 keV gamma-rays were observed, and their half-lives were approximately 2 min, 10 min, and 20 min. They respectively correspond to the beta+ decay of 15O, 13N, and 11C. The SCE frequencies in CHO cells increased depending on the amount of radioactivation in the solution. These were suppressed with a 2-hour delayed solution transfer or pretreatment with dimethyl sulfoxide (DMSO). Our results suggest that the SCE induction by radioactivated solution was mediated by free radicals produced by the annihilated gamma-rays. Since the SCE induction and DMSO modulation are also reported in radiation-induced bystander effects, our results imply that radioactivation of the solution may have some contribution to the bystander effects from hadron radiation. Further investigations are required to assess if radioactivation effects would attribute an additional level of cancer risk of the hadron radiation therapy itself.

  16. Solution Radioactivated by Hadron Radiation Can Increase Sister Chromatid Exchanges.

    Directory of Open Access Journals (Sweden)

    Junko Maeda

    Full Text Available When energetic particles irradiate matter, it becomes activated by nuclear reactions. Radioactivation induced cellular effects are not clearly understood, but it could be a part of bystander effects. This investigation is aimed at understanding the biological effects from radioactivation in solution induced by hadron radiation. Water or phosphate buffered saline was activated by being exposed to hadron radiation including protons, carbon- and iron-ions. 1 mL of radioactivated solution was transferred to flasks with Chinese hamster ovary (CHO cells cultured in 5 mL of complete media. The induction of sister chromatid exchanges (SCE was used to observe any increase in DNA damage responses. The energy spectrum and the half-lives of the radioactivation were analyzed by NaI scintillation detector in order to identify generated radionuclides. In the radioactivated solution, 511 keV gamma-rays were observed, and their half-lives were approximately 2 min, 10 min, and 20 min. They respectively correspond to the beta+ decay of 15O, 13N, and 11C. The SCE frequencies in CHO cells increased depending on the amount of radioactivation in the solution. These were suppressed with a 2-hour delayed solution transfer or pretreatment with dimethyl sulfoxide (DMSO. Our results suggest that the SCE induction by radioactivated solution was mediated by free radicals produced by the annihilated gamma-rays. Since the SCE induction and DMSO modulation are also reported in radiation-induced bystander effects, our results imply that radioactivation of the solution may have some contribution to the bystander effects from hadron radiation. Further investigations are required to assess if radioactivation effects would attribute an additional level of cancer risk of the hadron radiation therapy itself.

  17. Cell biology of cancer: BRCA1 and sister chromatid pairing reactions?

    Science.gov (United States)

    Skibbens, Robert V

    2008-02-15

    A significant portion of familial breast/ovarian cancer patients harbors a mutation in Breast Cancer Associated gene 1 (BRCA1). Cells deficient for BRCA1 exhibit chromosome aberrations such as whole chromosome duplications, translocations, inter-sister gaps and gene mis-regulation. Here, new evidence is reviewed that defects in sister chromatid cohesion may contribute directly to cancer cell phenotypes-especially those of BRCA1 mutant cells. Linking cohesion to BRCA1-dependent tumorigenesis are reports that BRCA1-associated components (DNA helicase, RFC, PCNA and genome surveillance factors) are required for efficient sister chromatid cohesion. Other cohesion factors (WAPL, EFO2/ESCO2 and hSecurin) are tightly correlated with various cell-type specific carcinogenesis, in support of a generalized model for cohesion in cancer. Recent findings further reveal that a reciprocal relationship exists in that DNA damage induces new Ctf7/Eco1-dependent sister chromatid pairing reactions that, in turn, are required for efficient DNA repair. Future research into sister chromatid pairing mechanisms are likely to provide critical new insights into the underlying causes of cancer.

  18. Mouse RAD54 Affects DNA Double-Strand Break Repair and Sister Chromatid Exchange

    Science.gov (United States)

    Dronkert, Mies L. G.; Beverloo, H. Berna; Johnson, Roger D.; Hoeijmakers, Jan H. J.; Jasin, Maria; Kanaar, Roland

    2000-01-01

    Cells can achieve error-free repair of DNA double-strand breaks (DSBs) by homologous recombination through gene conversion with or without crossover. In contrast, an alternative homology-dependent DSB repair pathway, single-strand annealing (SSA), results in deletions. In this study, we analyzed the effect of mRAD54, a gene involved in homologous recombination, on the repair of a site-specific I-SceI-induced DSB located in a repeated DNA sequence in the genome of mouse embryonic stem cells. We used six isogenic cell lines differing solely in the orientation of the repeats. The combination of the three recombination-test substrates used discriminated among SSA, intrachromatid gene conversion, and sister chromatid gene conversion. DSB repair was most efficient for the substrate that allowed recovery of SSA events. Gene conversion with crossover, indistinguishable from long tract gene conversion, preferentially involved the sister chromatid rather than the repeat on the same chromatid. Comparing DSB repair in mRAD54 wild-type and knockout cells revealed direct evidence for a role of mRAD54 in DSB repair. The substrate measuring SSA showed an increased efficiency of DSB repair in the absence of mRAD54. The substrate measuring sister chromatid gene conversion showed a decrease in gene conversion with and without crossover. Consistent with this observation, DNA damage-induced sister chromatid exchange was reduced in mRAD54-deficient cells. Our results suggest that mRAD54 promotes gene conversion with predominant use of the sister chromatid as the repair template at the expense of error-prone SSA. PMID:10757799

  19. Bromodeoxyuridine does not contribute to sister chromatid exchange events in normal or Bloom syndrome cells

    NARCIS (Netherlands)

    van Wietmarschen, Niek; Lansdorp, Peter M.

    2016-01-01

    Sister chromatid exchanges (SCEs) are considered sensitive indicators of genome instability. Detection of SCEs typically requires cells to incorporate bromodeoxyuridine (BrdU) during two rounds of DNA synthesis. Previous studies have suggested that SCEs are induced by DNA replication over BrdU-subst

  20. Metazoan Scc4 homologs link sister chromatid cohesion to cell and axon migration guidance

    NARCIS (Netherlands)

    V.C. Seitan (Vlad); P.A. Banks (Peter); S. Laval (Steve); N.A. Majid (Nazia); D. Dorsett (Dale); A. Rana (Amer); J. Smith (Jeremy); A. Bateman (Alex); S. Krpic (Sanja); A. Hostert (Arnd); S.M. Rollins; H. Erdjument-Bromage (Hediye); P. Tempst (Paul); C.Y. Benard (Claire); S. Hekimi (Siegfried); S.F. Newbury (Sarah); T. Strachan (Tom)

    2006-01-01

    textabstractSaccharomyces cerevisiae Scc2 binds Scc4 to form an essential complex that loads cohesin onto chromosomes. The prevalence of Scc2 orthologs in eukaryotes emphasizes a conserved role in regulating sister chromatid cohesion, but homologs of Scc4 have not hitherto been identified outside ce

  1. Effect of borax on immune cell proliferation and sister chromatid exchange in human chromosomes

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    Pongsavee Malinee

    2009-10-01

    Full Text Available Abstract Background Borax is used as a food additive. It becomes toxic when accumulated in the body. It causes vomiting, fatigue and renal failure. Methods The heparinized blood samples from 40 healthy men were studied for the impact of borax toxicity on immune cell proliferation (lymphocyte proliferation and sister chromatid exchange in human chromosomes. The MTT assay and Sister Chromatid Exchange (SCE technic were used in this experiment with the borax concentrations of 0.1, 0.15, 0.2, 0.3 and 0.6 mg/ml. Results It showed that the immune cell proliferation (lymphocyte proliferation was decreased when the concentrations of borax increased. The borax concentration of 0.6 mg/ml had the most effectiveness to the lymphocyte proliferation and had the highest cytotoxicity index (CI. The borax concentrations of 0.15, 0.2, 0.3 and 0.6 mg/ml significantly induced sister chromatid exchange in human chromosomes (P Conclusion Borax had effects on immune cell proliferation (lymphocyte proliferation and induced sister chromatid exchange in human chromosomes. Toxicity of borax may lead to cellular toxicity and genetic defect in human.

  2. SISTER-CHROMATID EXCHANGES IN CULTURED IMMATURE EMBRYOS OF WHEAT SPECIES AND REGENERANTS

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1994-01-01

    Immature embryos of Triticum aestivum (ten cultivars and lines), T. durum, T. dicoccum and T. monococcum were cultured in vitro on MS medium supplemented with 1 or 2 mg/l of 2,4-D and 20 or 30g/l of sucrose for 3 days and processed to score sister chromatid exchanges (SCEs) per chromosome. Media com

  3. Comparison of genome stability in two pig breeds by using the sister chromatid exchange (SCE test

    Directory of Open Access Journals (Sweden)

    V. Barbieri

    2010-01-01

    Full Text Available The sister chromatid exchange (SCE test has been used to detect genome stability in humans (Chaganti, 1974 and the main livestock species (Ciotola et al., 2004; Di Meo et al., 2000; Di Berardino et al., 1979, and to discover DNA damage caused by a variety of natural and artificial chemical compounds (Iannuzzi et al., 1990.

  4. Bromodeoxyuridine does not contribute to sister chromatid exchange events in normal or Bloom syndrome cells

    NARCIS (Netherlands)

    van Wietmarschen, Niek; Lansdorp, Peter M.

    2016-01-01

    Sister chromatid exchanges (SCEs) are considered sensitive indicators of genome instability. Detection of SCEs typically requires cells to incorporate bromodeoxyuridine (BrdU) during two rounds of DNA synthesis. Previous studies have suggested that SCEs are induced by DNA replication over BrdU-subst

  5. Bloom Helicase and DNA Topoisomerase IIIα Are Involved in the Dissolution of Sister Chromatids

    Science.gov (United States)

    Seki, Masayuki; Nakagawa, Takayuki; Seki, Takahiko; Kato, Genta; Tada, Shusuke; Takahashi, Yuriko; Yoshimura, Akari; Kobayashi, Takayuki; Aoki, Ayako; Otsuki, Makoto; Habermann, Felix A.; Tanabe, Hideyuki; Ishii, Yutaka; Enomoto, Takemi

    2006-01-01

    Bloom's syndrome (BS) is an autosomal disorder characterized by predisposition to a wide variety of cancers. The gene product whose mutation leads to BS is the RecQ family helicase BLM, which forms a complex with DNA topoisomerase IIIα (Top3α). However, the physiological relevance of the interaction between BLM and Top3α within the cell remains unclear. We show here that Top3α depletion causes accumulation of cells in G2 phase, enlargement of nuclei, and chromosome gaps and breaks that occur at the same position in sister chromatids. The transition from metaphase to anaphase is also inhibited. All of these phenomena except cell lethality are suppressed by BLM gene disruption. Taken together with the biochemical properties of BLM and Top3α, these data indicate that BLM and Top3α execute the dissolution of sister chromatids. PMID:16880537

  6. Functional genomics identifies a requirement of pre-mRNA splicing factors for sister chromatid cohesion.

    Science.gov (United States)

    Sundaramoorthy, Sriramkumar; Vázquez-Novelle, María Dolores; Lekomtsev, Sergey; Howell, Michael; Petronczki, Mark

    2014-11-18

    Sister chromatid cohesion mediated by the cohesin complex is essential for chromosome segregation during cell division. Using functional genomic screening, we identify a set of 26 pre-mRNA splicing factors that are required for sister chromatid cohesion in human cells. Loss of spliceosome subunits increases the dissociation rate of cohesin from chromatin and abrogates cohesion after DNA replication, ultimately causing mitotic catastrophe. Depletion of splicing factors causes defective processing of the pre-mRNA encoding sororin, a factor required for the stable association of cohesin with chromatin, and an associated reduction of sororin protein level. Expression of an intronless version of sororin and depletion of the cohesin release protein WAPL suppress the cohesion defect in cells lacking splicing factors. We propose that spliceosome components contribute to sister chromatid cohesion and mitotic chromosome segregation through splicing of sororin pre-mRNA. Our results highlight the loss of cohesion as an early cellular consequence of compromised splicing. This may have clinical implications because SF3B1, a splicing factor that we identify to be essential for cohesion, is recurrently mutated in chronic lymphocytic leukaemia.

  7. Premature Sister Chromatid Separation Is Poorly Detected by the Spindle Assembly Checkpoint as a Result of System-Level Feedback

    OpenAIRE

    Mihailo Mirkovic; Lukas H. Hutter; Béla Novák; Raquel A. Oliveira

    2015-01-01

    Sister chromatid cohesion, mediated by the cohesin complex, is essential for faithful mitosis. Nevertheless, evidence suggests that the surveillance mechanism that governs mitotic fidelity, the spindle assembly checkpoint (SAC), is not robust enough to halt cell division when cohesion loss occurs prematurely. The mechanism behind this poor response is not properly understood. Using developing Drosophila brains, we show that full sister chromatid separation elicits a weak checkpoint response r...

  8. Premature Sister Chromatid Separation Is Poorly Detected by the Spindle Assembly Checkpoint as a Result of System-Level Feedback

    OpenAIRE

    Mirkovic, Mihailo; Hutter, Lukas H.; Novák, Béla; Oliveira, Raquel A.

    2015-01-01

    Sister chromatid cohesion, mediated by the cohesin complex, is essential for faithful mitosis. Nevertheless, evidence suggests that the surveillance mechanism that governs mitotic fidelity, the spindle assembly checkpoint (SAC), is not robust enough to halt cell division when cohesion loss occurs prematurely. The mechanism behind this poor response is not properly understood. Using developing Drosophila brains, we show that full sister chromatid separation elicits a weak checkpoint response r...

  9. Opposing Functions of the N-terminal Acetyltransferases Naa50 and NatA in Sister-chromatid Cohesion.

    Science.gov (United States)

    Rong, Ziye; Ouyang, Zhuqing; Magin, Robert S; Marmorstein, Ronen; Yu, Hongtao

    2016-09-02

    During the cell cycle, sister-chromatid cohesion tethers sister chromatids together from S phase to the metaphase-anaphase transition and ensures accurate segregation of chromatids into daughter cells. N-terminal acetylation is one of the most prevalent protein covalent modifications in eukaryotes and is mediated by a family of N-terminal acetyltransferases (NAT). Naa50 (also called San) has previously been shown to play a role in sister-chromatid cohesion in metazoans. The mechanism by which Naa50 contributes to cohesion is not understood however. Here, we show that depletion of Naa50 in HeLa cells weakens the interaction between cohesin and its positive regulator sororin and causes cohesion defects in S phase, consistent with a role of Naa50 in cohesion establishment. Strikingly, co-depletion of NatA, a heterodimeric NAT complex that physically interacts with Naa50, rescues the sister-chromatid cohesion defects and the resulting mitotic arrest caused by Naa50 depletion, indicating that NatA and Naa50 play antagonistic roles in cohesion. Purified recombinant NatA and Naa50 do not affect each other's NAT activity in vitro Because NatA and Naa50 exhibit distinct substrate specificity, we propose that they modify different effectors and regulate sister-chromatid cohesion in opposing ways.

  10. Cyclin A2 Is Required for Sister Chromatid Segregation, But Not Separase Control, in Mouse Oocyte Meiosis

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    Sandra A. Touati

    2012-11-01

    Full Text Available In meiosis, two specialized cell divisions allow the separation of paired chromosomes first, then of sister chromatids. Separase removes the cohesin complex holding sister chromatids together in a stepwise manner from chromosome arms in meiosis I, then from the centromere region in meiosis II. Using mouse oocytes, our study reveals that cyclin A2 promotes entry into meiosis, as well as an additional unexpected role; namely, its requirement for separase-dependent sister chromatid separation in meiosis II. Untimely cyclin A2-associated kinase activity in meiosis I leads to precocious sister separation, whereas inhibition of cyclin A2 in meiosis II prevents it. Accordingly, endogenous cyclin A is localized to kinetochores throughout meiosis II, but not in anaphase I. Additionally, we found that cyclin B1, but not cyclin A2, inhibits separase in meiosis I. These findings indicate that separase-dependent cohesin removal is differentially regulated by cyclin B1 and A2 in mammalian meiosis.

  11. Cyclin A2 is required for sister chromatid segregation, but not separase control, in mouse oocyte meiosis.

    Science.gov (United States)

    Touati, Sandra A; Cladière, Damien; Lister, Lisa M; Leontiou, Ioanna; Chambon, Jean-Philippe; Rattani, Ahmed; Böttger, Franziska; Stemmann, Olaf; Nasmyth, Kim; Herbert, Mary; Wassmann, Katja

    2012-11-29

    In meiosis, two specialized cell divisions allow the separation of paired chromosomes first, then of sister chromatids. Separase removes the cohesin complex holding sister chromatids together in a stepwise manner from chromosome arms in meiosis I, then from the centromere region in meiosis II. Using mouse oocytes, our study reveals that cyclin A2 promotes entry into meiosis, as well as an additional unexpected role; namely, its requirement for separase-dependent sister chromatid separation in meiosis II. Untimely cyclin A2-associated kinase activity in meiosis I leads to precocious sister separation, whereas inhibition of cyclin A2 in meiosis II prevents it. Accordingly, endogenous cyclin A is localized to kinetochores throughout meiosis II, but not in anaphase I. Additionally, we found that cyclin B1, but not cyclin A2, inhibits separase in meiosis I. These findings indicate that separase-dependent cohesin removal is differentially regulated by cyclin B1 and A2 in mammalian meiosis.

  12. Metazoan Scc4 homologs link sister chromatid cohesion to cell and axon migration guidance.

    Directory of Open Access Journals (Sweden)

    Vlad C Seitan

    2006-07-01

    Full Text Available Saccharomyces cerevisiae Scc2 binds Scc4 to form an essential complex that loads cohesin onto chromosomes. The prevalence of Scc2 orthologs in eukaryotes emphasizes a conserved role in regulating sister chromatid cohesion, but homologs of Scc4 have not hitherto been identified outside certain fungi. Some metazoan orthologs of Scc2 were initially identified as developmental gene regulators, such as Drosophila Nipped-B, a regulator of cut and Ultrabithorax, and delangin, a protein mutant in Cornelia de Lange syndrome. We show that delangin and Nipped-B bind previously unstudied human and fly orthologs of Caenorhabditis elegans MAU-2, a non-axis-specific guidance factor for migrating cells and axons. PSI-BLAST shows that Scc4 is evolutionarily related to metazoan MAU-2 sequences, with the greatest homology evident in a short N-terminal domain, and protein-protein interaction studies map the site of interaction between delangin and human MAU-2 to the N-terminal regions of both proteins. Short interfering RNA knockdown of human MAU-2 in HeLa cells resulted in precocious sister chromatid separation and in impaired loading of cohesin onto chromatin, indicating that it is functionally related to Scc4, and RNAi analyses show that MAU-2 regulates chromosome segregation in C. elegans embryos. Using antisense morpholino oligonucleotides to knock down Xenopus tropicalis delangin or MAU-2 in early embryos produced similar patterns of retarded growth and developmental defects. Our data show that sister chromatid cohesion in metazoans involves the formation of a complex similar to the Scc2-Scc4 interaction in the budding yeast. The very high degree of sequence conservation between Scc4 homologs in complex metazoans is consistent with increased selection pressure to conserve additional essential functions, such as regulation of cell and axon migration during development.

  13. Rfc5p regulates alternate RFC complex functions in sister chromatid pairing reactions in budding yeast

    OpenAIRE

    Maradeo, Marie E.; Garg, Anisha; Skibbens, Robert V.

    2010-01-01

    Sister chromatid pairing reactions, termed cohesion establishment, occur during S phase and appear to be regulated by replication factor C (RFC) complexes. For instance, RFCs that contain Ctf18p exhibit pro-establishment activities while those that contain Elg1p exhibit anti-establishment activities. It remains unknown whether Ctf18p-RFC and Elg1p-RFC functions are simply opposing or instead reveal complicated and non-parallel regulatory mechanisms. To better understand the nature of these no...

  14. Diagnostic insonation of extra uteri human placentas: no effect of lymphocytic sister chromatid exchange

    Energy Technology Data Exchange (ETDEWEB)

    Brulfert, A.; Ciaravino, V.; Miller, M.W.; Maulik, D.; Carstensen, E.L.

    1984-01-01

    Freshly delivered human placentas were exposed to ultrasound for 30 min using a diagnostic linear array unit. Blood was then drawn and cultured in the presence of bromodeoxyuridine, and the frequencies of sister chromatid exchanges (SCE) in the lymphocytes determined. There was no statistically significant difference in SCE frequencies between control and exposed cells; the frequencies of SCEs per cell ranged from 4.50 to 6.02 for control and from 4.66 to 6.10 for exposed cells in five separate experiments. Positive control mitomycin C treated cells were significantly affected, with more than 50 SCEs per cell. 20 references, 1 table.

  15. A proposal of a standardised nomenclature for terminal minute sister chromatid exchanges

    Directory of Open Access Journals (Sweden)

    Máximo E. Drets

    2006-01-01

    Full Text Available We described spontaneous minute sister chromatid exchanges (SCE in telomeric regions of human and Chinese hamster ovary (CHO chromosomes more than 10 years ago. These structures, which we called t-SCE, were detected by means of highly precise quantitative microphotometrical scanning and computer graphic image analysis. Recently, several authors using the CO-FISH method also found small SCEs in telomeric regions and called them T-SCE. The use of different terms for designating the same phenomenon should be avoided. We propose ter SCE as a uniform nomenclature for minute telomeric SCEs.

  16. The PP2A inhibitor I2PP2A is essential for sister chromatid segregation in oocyte meiosis II.

    Science.gov (United States)

    Chambon, Jean-Philippe; Touati, Sandra A; Berneau, Stéphane; Cladière, Damien; Hebras, Céline; Groeme, Rachel; McDougall, Alex; Wassmann, Katja

    2013-03-18

    Haploid gametes are generated through two consecutive meiotic divisions, with the segregation of chromosome pairs in meiosis I and sister chromatids in meiosis II. Separase-mediated stepwise removal of cohesion, first from chromosome arms and later from the centromere region, is a prerequisite for maintaining sister chromatids together until their separation in meiosis II [1]. In all model organisms, centromeric cohesin is protected from separase-dependent removal in meiosis I through the activity of PP2A-B56 phosphatase, which is recruited to centromeres by shugoshin/MEI-S332 (Sgo) [2-5]. How this protection of centromeric cohesin is removed in meiosis II is not entirely clear; we find that all the PP2A subunits remain colocalized with the cohesin subunit Rec8 at the centromere of metaphase II chromosomes. Here, we show that sister chromatid separation in oocytes depends on a PP2A inhibitor, namely I2PP2A. I2PP2A colocalizes with the PP2A enzyme at centromeres at metaphase II, independently of bipolar attachment. When I2PP2A is depleted, sister chromatids fail to segregate during meiosis II. Our findings demonstrate that in oocytes I2PP2A is essential for faithful sister chromatid segregation by mediating deprotection of centromeric cohesin in meiosis II. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Investigating the in vitro effect of taurine on the infant lymphocytes by sister chromatid exchange.

    Science.gov (United States)

    Ergun, Mehmet Ali; Soysal, Yasemin; Kismet, Erol; Akay, Cemal; Dundaroz, Rusen; Ilhan, Mustafan; Imirzalioglu, Necat

    2006-06-01

    Taurine (2-aminoethane sulphonic acid) is normally present in most mammalian tissues and the most abundant free amino acid in lymphocytes. It participates in various important physiological activities including modulation of the functioning of the central nervous system, cell proliferation, viability and prevention of oxidant-induced injury in many tissues. Its levels in human milk are very high which may be the most important difference from cow's milk. In contrast, an inverse association between breast-feeding and carcinogenesis in childhood or later in life has been suggested by several studies. The study group consisted of eight healthy infants. Peripheral blood was collected and lymphocytes were cultured with either Taurine or Mitomycin C (MMC). Sister chromatid exchange in lymphocytes of the infants were calculated. Statistical differences were found between untreated and MMC-treated lymphocytes, untreated and MMC plus taurine-treated lymphocytes, and between MMC and MMC plus taurine-treated lymphocytes (P = 0.012). The results indicated that taurine plays a protective role in MMC-induced sister chromatid exchange in human lymphocytes. The authors suggest that the high levels of taurine found in human milk may induce protecting effects from breast-feeding against DNA damage and malignancy.

  18. The ELG1 clamp loader plays a role in sister chromatid cohesion.

    Directory of Open Access Journals (Sweden)

    Oren Parnas

    Full Text Available Mutations in the ELG1 gene of yeast lead to genomic instability, manifested in high levels of genetic recombination, chromosome loss, and gross chromosomal rearrangements. Elg1 shows similarity to the large subunit of the Replication Factor C clamp loader, and forms a RFC-like (RLC complex in conjunction with the 4 small RFC subunits. Two additional RLCs exist in yeast: in one of them the large subunit is Ctf18, and in the other, Rad24. Ctf18 has been characterized as the RLC that functions in sister chromatid cohesion. Here we present evidence that the Elg1 RLC (but not Rad24 also plays an important role in this process. A genetic screen identified the cohesin subunit Mcd1/Scc1 and its loader Scc2 as suppressors of the synthetic lethality between elg1 and ctf4. We describe genetic interactions between ELG1 and genes encoding cohesin subunits and their accessory proteins. We also show that defects in Elg1 lead to higher precocious sister chromatid separation, and that Ctf18 and Elg1 affect cohesion via a joint pathway. Finally, we localize both Ctf18 and Elg1 to chromatin and show that Elg1 plays a role in the recruitment of Ctf18. Our results suggest that Elg1, Ctf4, and Ctf18 may coordinate the relative movement of the replication fork with respect to the cohesin ring.

  19. UV-induced chromosome aberrations, sister-chromatid exchanges and cell survival in cultured lymphocytes from malnourished children

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, P.B.; Rahiman, M.A.; Tulpule, P.G.

    1982-08-01

    Cultured lymphocytes from children with kwashiorkor and from normal children were examined for their susceptibility to ultraviolet (UV)-induced chromosome aberrations, sister-chromatid exchanges and cell survival. Cells from kwashiorkor exhibited increased chromosome aberrations, but not sister-chromatid exchanges, when exposed to higher doses of UV. Furthermore, when cells from these patients were exposed to higher doses of UV, there was a significant reduction in viability. These results indicate that, as compared to normals, cells from kwashiorkor were more sensitive to the lethal effects of UV.

  20. UBL5 is essential for pre-mRNA splicing and sister chromatid cohesion in human cells

    DEFF Research Database (Denmark)

    Oka, Yasuyoshi; Varmark, Hanne; Vitting-Seerup, Kristoffer;

    2014-01-01

    UBL5 is an atypical ubiquitin-like protein, whose function in metazoans remains largely unexplored. We show that UBL5 is required for sister chromatid cohesion maintenance in human cells. UBL5 primarily associates with spliceosomal proteins, and UBL5 depletion decreases pre-mRNA splicing efficiency......, leading to globally enhanced intron retention. Defective sister chromatid cohesion is a general consequence of dysfunctional pre-mRNA splicing, resulting from the selective downregulation of the cohesion protection factor Sororin. As the UBL5 yeast orthologue, Hub1, also promotes spliceosome functions...

  1. Bromodeoxyuridine does not contribute to sister chromatid exchange events in normal or Bloom syndrome cells.

    Science.gov (United States)

    van Wietmarschen, Niek; Lansdorp, Peter M

    2016-08-19

    Sister chromatid exchanges (SCEs) are considered sensitive indicators of genome instability. Detection of SCEs typically requires cells to incorporate bromodeoxyuridine (BrdU) during two rounds of DNA synthesis. Previous studies have suggested that SCEs are induced by DNA replication over BrdU-substituted DNA and that BrdU incorporation alone could be responsible for the high number of SCE events observed in cells from patients with Bloom syndrome (BS), a rare genetic disorder characterized by marked genome instability and high SCE frequency. Here we show using Strand-seq, a single cell DNA template strand sequencing technique, that the presence of variable BrdU concentrations in the cell culture medium and in DNA template strands has no effect on SCE frequency in either normal or BS cells. We conclude that BrdU does not induce SCEs and that SCEs detected in either normal or BS cells reflect DNA repair events that occur spontaneously.

  2. PICH promotes sister chromatid disjunction and co-operates with topoisomerase II in mitosis.

    Science.gov (United States)

    Nielsen, Christian F; Huttner, Diana; Bizard, Anna H; Hirano, Seiki; Li, Tian-Neng; Palmai-Pallag, Timea; Bjerregaard, Victoria A; Liu, Ying; Nigg, Erich A; Wang, Lily Hui-Ching; Hickson, Ian D

    2015-01-01

    PICH is a SNF2 family DNA translocase that binds to ultra-fine DNA bridges (UFBs) in mitosis. Numerous roles for PICH have been proposed from protein depletion experiments, but a consensus has failed to emerge. Here, we report that deletion of PICH in avian cells causes chromosome structural abnormalities, and hypersensitivity to an inhibitor of Topoisomerase II (Topo II), ICRF-193. ICRF-193-treated PICH(-/-) cells undergo sister chromatid non-disjunction in anaphase, and frequently abort cytokinesis. PICH co-localizes with Topo IIα on UFBs and at the ribosomal DNA locus, and the timely resolution of both structures depends on the ATPase activity of PICH. Purified PICH protein strongly stimulates the catalytic activity of Topo II in vitro. Consistent with this, a human PICH(-/-) cell line exhibits chromosome instability and chromosome condensation and decatenation defects similar to those of ICRF-193-treated cells. We propose that PICH and Topo II cooperate to prevent chromosome missegregation events in mitosis.

  3. Sister-chromatid exchange analysis in a rural population of Mexico exposed to pesticides.

    Science.gov (United States)

    Gómez-Arroyo, S; Noriega-Aldana, N; Osorio, A; Galicia, F; Ling, S; Villalobos-Pietrini, R

    1992-03-01

    Cytogenetic damage was evaluated by means of the analysis of sister-chromatid exchange (SCE) in a rural population of Tlaxcala, Mexico, in occupational contact with pesticides. We studied 170 men, 94 exposed and 76 not exposed. It was shown that SCE followed a normal distribution and Student's t test did not present differences between the two groups (P = 0.4). The frequency of SCE was not correlated with the duration of exposure of the rural workers (r = -0.06), the multiple covariance analysis applied to the data of duration of exposure, tobacco intake and alcohol ingestion demonstrated a lack of statistical significance. In the exposed people we observed no symptoms provoked by these compounds.

  4. Sororin pre-mRNA splicing is required for proper sister chromatid cohesion in human cells.

    Science.gov (United States)

    Watrin, Erwan; Demidova, Maria; Watrin, Tanguy; Hu, Zheng; Prigent, Claude

    2014-09-01

    Sister chromatid cohesion, which depends on cohesin, is essential for the faithful segregation of replicated chromosomes. Here, we report that splicing complex Prp19 is essential for cohesion in both G2 and mitosis, and consequently for the proper progression of the cell through mitosis. Inactivation of splicing factors SF3a120 and U2AF65 induces similar cohesion defects to Prp19 complex inactivation. Our data indicate that these splicing factors are all required for the accumulation of cohesion factor Sororin, by facilitating the proper splicing of its pre-mRNA. Finally, we show that ectopic expression of Sororin corrects defective cohesion caused by Prp19 complex inactivation. We propose that the Prp19 complex and the splicing machinery contribute to the establishment of cohesion by promoting Sororin accumulation during S phase, and are, therefore, essential to the maintenance of genome stability.

  5. Antimutagenic effect of crown ethers on heavy metal-induced sister chromatid exchanges.

    Science.gov (United States)

    Cai, M Y; Arenaz, P

    1998-01-01

    Macrocyclic polyethers (crown ethers) are a family of compounds that possess the ability to complex with and transport metal ions across membranes. Because of their unique ionophoric characteristic, they have wide application in industry and research, chemistry and biology. In the current investigation the relationship between heavy metal mutagenesis and crown ether co-mutagenicity and/or antimutagenicity in mammalian cells has been examined using sister chromatid exchange (SCE) as the cytogenetic end point. Chinese hamster ovary cells were treated with lead or cadmium, with and without selected crown ethers. Several genotoxic end points, including SCEs were scored and statistically compared. We report here that most of the crown ethers studied had little or no influence on lead- or cadmium-induced SCEs or chromosome aberrations. On the other hand, the substituted crown ether dicyclohexyl 21-crown-7 significantly decreased both spontaneous and metal-induced SCE frequencies, suggesting that this crown ether may possess antimutagenic activity.

  6. Sister chromatid exchange in human populations: the effect of smoking, drug treatment, and occupational exposure

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, B.; Bredberg, A.; McKenzie, W.; Sten, M.

    1982-01-01

    Increased rate of sister chromatid exchange (SCE) in peripheral lymphocytes has been observed in smokers as compared to nonsmokers and in patients receiving certain cytostatic drugs. The increased SCE frequency in smokers was shown to depend on the number of cigarettes smoked per day, as well as on the duration of smoking. DNA cross-links caused by photochemotherapy against psoriasis, 8-methoxypsoralen plus UVA irradiation (PUVA), as well as by the anti-cancer chemotherapeutic agent CCNU, were shown to be more effective at inducing SCE's than other types of DNA damage caused by these treatments. These observations suggest that SCE analysis may be used as an indicator of genotoxic exposure in vivo, provided that the various types of DNA damage caused by genotoxic agents and the dose, as well as the time of exposure in relation to the time of sampling, are considered.

  7. Regulation of the Drosophila Enhancer of split and invected-engrailed Gene Complexes by Sister Chromatid Cohesion Proteins

    NARCIS (Netherlands)

    Schaaf, Cheri A.; Misulovin, Ziva; Sahota, Gurmukh; Siddiqui, Akbar M.; Schwartz, Yuri B.; Kahn, Tatyana G.; Pirrotta, Vincenzo; Gause, Maria; Dorsett, Dale

    2009-01-01

    The cohesin protein complex was first recognized for holding sister chromatids together and ensuring proper chromosome segregation. Cohesin also regulates gene expression, but the mechanisms are unknown. Cohesin associates preferentially with active genes, and is generally absent from regions in whi

  8. The Elg1-RFC clamp-loading complex performs a role in sister chromatid cohesion.

    Science.gov (United States)

    Maradeo, Marie E; Skibbens, Robert V

    2009-01-01

    It is widely accepted that of the four Replication Factor C (RFC) complexes (defined by the associations of either Rfc1p, Ctf18p, Elg1p or Rad24p with Rfc2p-Rfc5p), only Ctf18-RFC functions in sister chromatid cohesion. This model is based on findings that CTF18 deletion is lethal in combination with mutations in either CTF7(ECO1) or MCD1 sister chromatid cohesion genes and that ctf18 mutant cells exhibit cohesion defects. Here, we report that Elg1-RFC not only participates in cohesion but performs a function that is distinct from that of Ctf18-RFC. The results show that deletion of ELG1 rescues both ctf7(eco1) mutant cell temperature sensitivity and cohesion defects. Moreover, over-expression of ELG1 enhances ctf7(eco1) mutant cell phenotypes. These findings suggest that the balance of Ctf7p(Eco1p) activity depends on both Ctf18-RFC and Elg1-RFC. We also report that ELG1 deletion produces cohesion defects and intensifies the conditional phenotype of mcd1 mutant cells, further supporting a role for Elg1-RFC in cohesion. Attesting to the specificity of these interactions, deletion of RAD24 neither suppressed nor exacerbated cohesion defects in either ctf7(eco1) or mcd1 mutant cells. While parallel analyses failed to uncover a similar role in cohesion for Rad24-RFC, it is well known that Rad24-RFC, Elg1-RFC and Ctf18-RFC play key roles in DNA damage responses. We tested and found that Ctf7p(Eco1p) plays a significant role in Rad24-RFC-based DNA response pathways. In combination, these findings challenge current views and document new and distinct roles for RFC complexes in cohesion and for Ctf7p(Eco1p) in DNA repair.

  9. The Elg1-RFC clamp-loading complex performs a role in sister chromatid cohesion.

    Directory of Open Access Journals (Sweden)

    Marie E Maradeo

    Full Text Available It is widely accepted that of the four Replication Factor C (RFC complexes (defined by the associations of either Rfc1p, Ctf18p, Elg1p or Rad24p with Rfc2p-Rfc5p, only Ctf18-RFC functions in sister chromatid cohesion. This model is based on findings that CTF18 deletion is lethal in combination with mutations in either CTF7(ECO1 or MCD1 sister chromatid cohesion genes and that ctf18 mutant cells exhibit cohesion defects. Here, we report that Elg1-RFC not only participates in cohesion but performs a function that is distinct from that of Ctf18-RFC. The results show that deletion of ELG1 rescues both ctf7(eco1 mutant cell temperature sensitivity and cohesion defects. Moreover, over-expression of ELG1 enhances ctf7(eco1 mutant cell phenotypes. These findings suggest that the balance of Ctf7p(Eco1p activity depends on both Ctf18-RFC and Elg1-RFC. We also report that ELG1 deletion produces cohesion defects and intensifies the conditional phenotype of mcd1 mutant cells, further supporting a role for Elg1-RFC in cohesion. Attesting to the specificity of these interactions, deletion of RAD24 neither suppressed nor exacerbated cohesion defects in either ctf7(eco1 or mcd1 mutant cells. While parallel analyses failed to uncover a similar role in cohesion for Rad24-RFC, it is well known that Rad24-RFC, Elg1-RFC and Ctf18-RFC play key roles in DNA damage responses. We tested and found that Ctf7p(Eco1p plays a significant role in Rad24-RFC-based DNA response pathways. In combination, these findings challenge current views and document new and distinct roles for RFC complexes in cohesion and for Ctf7p(Eco1p in DNA repair.

  10. An increase in telomere sister chromatid exchange in murine embryonic stem cells possessing critically shortened telomeres

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yisong [ORNL; Giannone, Richard J [ORNL; Wu, Jun [ORNL; Gomez, Marla V [ORNL; Liu, Yie [ORNL

    2005-01-01

    Telomerase deficiency leads to a progressive loss of telomeric DNA that eventually triggers cell apoptosis in human primary cells during prolonged growth in culture. Rare survivors can maintain telomere length through either activation of telomerase or recombination-based telomere lengthening, and thus proliferate indefinitely. We have explored the possibility that telomeres may be maintained through telomere sister chromatid exchange (T-SCE) in murine telomere reverse transcriptase-deficient (mTert -/-) splenocytes and ES cells. Because telomerase deficiency leads to gradual loss of telomeric DNA in mTert -/- splenocytes and ES cells and eventually to chromosomes with telomere signal-free ends (SFEs), we examined these cell types for evidence of sister chromatid exchange at telomeres, and observed an increase in T-SCEs only in a subset of mTert -/- splenocytes or ES cells that possessed multiple SFEs. Furthermore, T-SCEs were more often detected in ES cells than in splenocytes that harbored a similar frequency of SFEs. In mTert heterozygous (mTert +/-) ES cells or splenocytes, which are known to exhibit a decrease in average telomere length but no SFEs, no increase in T-SCE was observed. In addition to T-SCE, other genomic rearrangements (i.e., SCE) were also significantly increased in mTert -/- ES cells possessing critically short telomeres, but not in splenocytes. Our results suggest that animals and cell culture differ in their ability to carry out genomic rearrangements as a means of maintaining telomere integrity when telomeres become critically shortened.

  11. Frequent and efficient use of the sister chromatid for DNA double-strand break repair during budding yeast meiosis.

    Directory of Open Access Journals (Sweden)

    Tamara Goldfarb

    Full Text Available Recombination between homologous chromosomes of different parental origin (homologs is necessary for their accurate segregation during meiosis. It has been suggested that meiotic inter-homolog recombination is promoted by a barrier to inter-sister-chromatid recombination, imposed by meiosis-specific components of the chromosome axis. Consistent with this, measures of Holliday junction-containing recombination intermediates (joint molecules [JMs] show a strong bias towards inter-homolog and against inter-sister JMs. However, recombination between sister chromatids also has an important role in meiosis. The genomes of diploid organisms in natural populations are highly polymorphic for insertions and deletions, and meiotic double-strand breaks (DSBs that form within such polymorphic regions must be repaired by inter-sister recombination. Efforts to study inter-sister recombination during meiosis, in particular to determine recombination frequencies and mechanisms, have been constrained by the inability to monitor the products of inter-sister recombination. We present here molecular-level studies of inter-sister recombination during budding yeast meiosis. We examined events initiated by DSBs in regions that lack corresponding sequences on the homolog, and show that these DSBs are efficiently repaired by inter-sister recombination. This occurs with the same timing as inter-homolog recombination, but with reduced (2- to 3-fold yields of JMs. Loss of the meiotic-chromosome-axis-associated kinase Mek1 accelerates inter-sister DSB repair and markedly increases inter-sister JM frequencies. Furthermore, inter-sister JMs formed in mek1Δ mutants are preferentially lost, while inter-homolog JMs are maintained. These findings indicate that inter-sister recombination occurs frequently during budding yeast meiosis, with the possibility that up to one-third of all recombination events occur between sister chromatids. We suggest that a Mek1-dependent reduction in

  12. Smc5–Smc6 mediate DNA double-strand-break repair by promoting sister-chromatid recombination

    Science.gov (United States)

    De Piccoli, Giacomo; Cortes-Ledesma, Felipe; Ira, Gregory; Torres-Rosell, Jordi; Uhle, Stefan; Farmer, Sarah; Hwang, Ji-Young; Machin, Felix; Ceschia, Audrey; McAleenan, Alexandra; Cordon-Preciado, Violeta; Clemente-Blanco, Andrés; Vilella-Mitjana, Felip; Ullal, Pranav; Jarmuz, Adam; Leitao, Beatriz; Bressan, Debra; Dotiwala, Farokh; Papusha, Alma; Zhao, Xiaolan; Myung, Kyungjae; Haber, James E.; Aguilera, Andrés; Aragón, Luis

    2015-01-01

    DNA double-strand breaks (DSB) can arise during DNA replication, or after exposure to DNA-damaging agents, and their correct repair is fundamental for cell survival and genomic stability. Here, we show that the Smc5–Smc6 complex is recruited to DSBs de novo to support their repair by homologous recombination between sister chromatids. In addition, we demonstrate that Smc5–Smc6 is necessary to suppress gross chromosomal rearrangements. Our findings show that the Smc5–Smc6 complex is essential for genome stability as it promotes repair of DSBs by error-free sister-chromatid recombination (SCR), thereby suppressing inappropriate non-sister recombination events. PMID:16892052

  13. Role of the Saccharomyces cerevisiae Rad51 paralogs in sister chromatid recombination.

    Science.gov (United States)

    Mozlin, Amy M; Fung, Cindy W; Symington, Lorraine S

    2008-01-01

    Rad51 requires a number of other proteins, including the Rad51 paralogs, for efficient recombination in vivo. Current evidence suggests that the yeast Rad51 paralogs, Rad55 and Rad57, are important in formation or stabilization of the Rad51 nucleoprotein filament. To gain further insights into the function of the Rad51 paralogs, reporters were designed to measure spontaneous or double-strand break (DSB)-induced sister or nonsister recombination. Spontaneous sister chromatid recombination (SCR) was reduced 6000-fold in the rad57 mutant, significantly more than in the rad51 mutant. Although the DSB-induced recombination defect of rad57 was suppressed by overexpression of Rad51, elevated temperature, or expression of both mating-type alleles, the rad57 defect in spontaneous SCR was not strongly suppressed by these same factors. In addition, the UV sensitivity of the rad57 mutant was not strongly suppressed by MAT heterozygosity, even though Rad51 foci were restored under these conditions. This lack of suppression suggests that Rad55 and Rad57 have different roles in the recombinational repair of stalled replication forks compared with DSB repair. Furthermore, these data suggest that most spontaneous SCR initiates from single-stranded gaps formed at stalled replication forks rather than DSBs.

  14. Premature Sister Chromatid Separation Is Poorly Detected by the Spindle Assembly Checkpoint as a Result of System-Level Feedback

    Directory of Open Access Journals (Sweden)

    Mihailo Mirkovic

    2015-10-01

    Full Text Available Sister chromatid cohesion, mediated by the cohesin complex, is essential for faithful mitosis. Nevertheless, evidence suggests that the surveillance mechanism that governs mitotic fidelity, the spindle assembly checkpoint (SAC, is not robust enough to halt cell division when cohesion loss occurs prematurely. The mechanism behind this poor response is not properly understood. Using developing Drosophila brains, we show that full sister chromatid separation elicits a weak checkpoint response resulting in abnormal mitotic exit after a short delay. Quantitative live-cell imaging approaches combined with mathematical modeling indicate that weak SAC activation upon cohesion loss is caused by weak signal generation. This is further attenuated by several feedback loops in the mitotic signaling network. We propose that multiple feedback loops involving cyclin-dependent kinase 1 (Cdk1 gradually impair error-correction efficiency and accelerate mitotic exit upon premature loss of cohesion. Our findings explain how cohesion defects may escape SAC surveillance.

  15. Rfc5p regulates alternate RFC complex functions in sister chromatid pairing reactions in budding yeast.

    Science.gov (United States)

    Maradeo, Marie E; Garg, Anisha; Skibbens, Robert V

    2010-11-01

    Sister chromatid pairing reactions, termed cohesion establishment, occur during S-phase and appear to be regulated by Replication Factor C (RFC) complexes. For instance, RFCs that contain Ctf18p exhibit pro-establishment activities while those that contain Elg1p exhibit anti-establishment activities. It remains unknown whether Ctf18p-RFC and Elg1p-RFC functions are simply opposing or instead reveal complicated and non-parallel regulatory mechanisms. To better understand the nature of these novel pathways, we analyzed the small RFC subunit Rfc5p that is common to both Ctf18p-RFC and Elg1p-RFC. Despite this commonality, the data show that diminished Rfc5p function rescues ctf7/eco1 mutant cell phenotypes, revealing that Rfc5p promotes anti-establishment activities. This rescue is specific to establishment pathways in that rfc5-1 greatly accentuates growth defects when expressed in scc2 (deposition), mcd1/scc1 or smc3 (cohesion maintenance) mutated cells. Our results reveal for the first time a role for small RFC subunits in directing RFC complex functions-in this case towards anti-establishment pathways. We further report that Pds5p exhibits both establishment and anti-establishment functions in cohesion. This duality suggests that categorizations of establishment and anti-establishment activities require further examination.

  16. In vitro genotoxicity of fipronil sister chromatid exchange, cytokinesis block micronucleus test, and comet assay.

    Science.gov (United States)

    Çelik, Ayla; Ekinci, Seda Yaprak; Güler, Gizem; Yildirim, Seda

    2014-03-01

    Fipronil (FP) is a phenylpyrazole pesticide developed by the transnational company Rhône-Poulenc Agro in 1987. Data on the genotoxicity and toxicity of FP are rather inadequate. In this study, we aimed to evaluate the potential genotoxic activity of FP using the single-cell microgel electrophoresis or comet assay, sister chromatid exchanges (SCEs), and micronuclei (MN) in human peripheral blood lymphocytes. In addition, the cytokinesis block proliferation index (CBPI) and proliferation index (PRI) were measured for cytotoxicity. In this study, three different doses of FP were used (0.7, 0.3, 0.1 μg/mL). Mitomycin C (2 μg/mL) and hydrogen peroxide were used as positive controls for SCE MN test systems, and comet assay, respectively. FP induced a statistically significant increase in the MN and SCE frequency and DNA damage in a dose-dependent manner in human peripheral blood lymphocytes (pcomet assay, we showed that all the doses of the FP induced DNA damage in human peripheral blood lymphocytes in vitro (p<0.05).

  17. A high rate of telomeric sister chromatid exchange occurs in chronic lymphocytic leukaemia B-cells.

    Science.gov (United States)

    Medves, Sandrine; Auchter, Morgan; Chambeau, Laetitia; Gazzo, Sophie; Poncet, Delphine; Grangier, Blandine; Verney, Aurélie; Moussay, Etienne; Ammerlaan, Wim; Brisou, Gabriel; Morjani, Hamid; Géli, Vincent; Palissot, Valérie; Berchem, Guy; Salles, Gilles; Wenner, Thomas

    2016-07-01

    Cancer cells protect their telomere ends from erosion through reactivation of telomerase or by using the Alternative Lengthening of Telomere (ALT) mechanism that depends on homologous recombination. Chronic lymphocytic leukaemia (CLL) B cells are characterized by almost no telomerase activity, shelterin deregulation and telomere fusions. To characterize telomeric maintenance mechanisms in B-CLL patients, we measured their telomere length, telomerase expression and the main hallmarks of the ALT activity i.e. C-circle concentration, an extra-chromosomal telomere repeat (ECTR), and the level of telomeric sister chromatid exchange (T-SCE) rate. Patients showed relative homogenous telomere length although almost no TERT transcript and nearly no C-circle were evidenced. Nevertheless, compared with normal B cells, B-CLL cells showed an increase in T-SCE rate that was correlated with a strong down-regulation of the topoisomerase III alpha (TOP3A) expression, involved in the dissolution of Holliday Junctions (HJ), together with an increased expression of SLX1A, SLX4, MUS81 and GEN1, involved in the resolution of HJ. Altogether, our results suggest that the telomere maintenance mechanism of B-CLL cells do not preferentially use telomerase or ALT. Rather, the rupture of the dissolvasome/resolvasome balance may increase telomere shuffling that could homogenize telomere length, slowing telomere erosion in this disease.

  18. Sister chromatid exchange in human lymphocytes induced by propoxur following plant activation by Vicia faba.

    Science.gov (United States)

    Gómez-Arroyo, S; Calderón-Segura, M E; Villalobos-Pietrini, R

    1995-01-01

    Because the carbamate insecticide propoxur induced sister chromatid exchanges (SCE) in Vicia faba but was ineffective in producing SCE in lymphocytes in culture, it was hardly suspected that plant metabolism was involved. Experiments were conducted in which metabolic activation was afforded by Vicia faba roots, and SCE in human lymphocytes in vitro was used to assess cytogenetic damage. Several concentrations of propoxur (250, 500, 1,000, 1,500, and 2,000 ppm) were applied for 4 hr to the roots of Vicia faba. Extracts prepared from these treatments were added to the lymphocyte cultures and a significant increase of SCE frequencies with a concentration-response relationship could be detected. The lymphocyte proliferation kinetics and the proliferation rate index (PRI) were not affected (except in the highest concentration, of 2,000 ppm). This general behavior was in agreement with the presence of an enzymatic system (S10 fraction) in Vicia roots capable of metabolizing or activating the propoxur. With 2,000 ppm, cell necrosis was produced in Vicia; therefore, this extract did not induce SCE in lymphocytes. However, lymphocyte proliferation kinetics were delayed and PRI was significantly decreased. Ethanol, a promutagen activated by this plant, was applied directly to the lymphocyte cultures as a positive control, and the response was negative. On the other hand, the extracts of roots treated with ethanol increased the SCE to more than twice that of the negative control, but the lymphocyte proliferation kinetics and PRI were not affected.

  19. Health assessment of gasoline and fuel oxygenate vapors: micronucleus and sister chromatid exchange evaluations.

    Science.gov (United States)

    Schreiner, Ceinwen A; Hoffman, Gary M; Gudi, Ramadevi; Clark, Charles R

    2014-11-01

    Micronucleus and sister chromatid exchange (SCE) tests were performed for vapor condensate of baseline gasoline (BGVC), or gasoline with oxygenates, methyl tert-butyl ether (G/MTBE), ethyl tert butyl ether (G/ETBE), t-amyl methyl ether (G/TAME), diisopropyl ether (G/DIPE), t-butyl alcohol (TBA), or ethanol (G/EtOH). Sprague Dawley rats (the same 5/sex/group for both endpoints) were exposed to 0, 2000, 10,000, or 20,000mg/m(3) of each condensate, 6h/day, 5days/week over 4weeks. Positive controls (5/sex/test) were given cyclophosphamide IP, 24h prior to sacrifice at 5mg/kg (SCE test) and 40mg/kg (micronucleus test). Blood was collected from the abdominal aorta for the SCE test and femurs removed for the micronucleus test. Blood cell cultures were treated with 5μg/ml bromodeoxyuridine (BrdU) for SCE evaluation. No significant increases in micronucleated immature erythrocytes were observed for any test material. Statistically significant increases in SCE were observed in rats given BGVC alone or in female rats given G/MTBE. G/TAME induced increased SCE in both sexes at the highest dose only. Although DNA perturbation was observed for several samples, DNA damage was not expressed as increased micronuclei in bone marrow cells. Inclusion of oxygenates in gasoline did not increase the effects of gasoline alone or produce a cytogenetic hazard.

  20. Induction of sister chromatid exchanges by coal dust and tobacco snuff extracts in human peripheral lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, J.D.; Ong, T.

    1985-01-01

    The organic solvent extracts of sub-bituminous coal dust and tobacco snuff, both together and separately, were tested for the induction of sister chromatid exchanges (SCEs) in human peripheral lymphocytes. The results indicate that these extracts induced SCEs, and that when tested together synergistically induced SCEs in two of three donors. Studies with the organic solvent extracts of all five ranks of coal indicate that the extracts of bituminous, lignite, and peat, but not anthracite, induced SCEs. Similar experiments conducted with water extracts, induced SCEs, and that anthracite was equivocal. To determine whether individuals differed in their SCE responses to coal dust extracts, lymphocytes from five donors were tested with organic solvent extracts of bituminous and sub-bituminous coal. An analysis of variance indicates that the SCE response was significantly influenced by the donor and each of the two coal extracts. The findings presented here suggest that coal dust, with or without tobacco snuff, may play a role in the elevated incidence of gastric cancer in coal miners. Because water extracts of some ranks of coal induced SCEs, there exists the possibility of adverse environmental effects due to coal leachates.

  1. Iron-mediated induction of sister-chromatid exchanges by hydrogen peroxide and superoxide anion.

    Science.gov (United States)

    Larramendy, M; Mello-Filho, A C; Martins, E A; Meneghini, R

    1987-05-01

    When Chinese hamster fibroblasts were exposed to hydrogen peroxide or to a system consisting of xanthine oxidase and hypoxanthine, which generates superoxide anion plus hydrogen peroxide, sister-chromatid exchanges (SCEs) were formed in a dose-dependent manner. When the iron-complexing agent o-phenanthroline was present in the medium, however, the production of these SCEs was completely inhibited. This fact indicates that the Fenton reaction: Fe2+ + H2O2----OH0 + OH- + Fe3+ is responsible for the production of SCEs. When O2- and H2O2 were generated inside the cell by incubation with menadione, the production of SCE was prevented by co-incubation with copper diisopropylsalicylate, a superoxide dismutase mimetic agent. The most likely role of O2- is as a reducing agent of Fe3+: O2- + Fe3+----Fe2+ + O2, so that the sum of this and the Fenton reaction, i.e., the iron-catalyzed Haber-Weiss reaction, provides an explanation for the active oxygen species-induced SCE: H2O2 + O2(-)----OH- + OH0 + O2. According to this view, the OH radical thus produced is the agent which ultimately causes SCE. These results are discussed in comparison with other mechanisms previously proposed for induction of SCE by active oxygen species.

  2. Identification of RFC(Ctf18p, Ctf8p, Dcc1p): an alternative RFC complex required for sister chromatid cohesion in S. cerevisiae.

    Science.gov (United States)

    Mayer, M L; Gygi, S P; Aebersold, R; Hieter, P

    2001-05-01

    We have identified and characterized an alternative RFC complex RFC(Ctf18p, Ctf8p, Dcc1p) that is required for sister chromatid cohesion and faithful chromosome transmission. Ctf18p, Ctf8p, and Dcc1p interact physically in a complex with Rfc2p, Rfc3p, Rfc4p, and Rfc5p but not with Rfc1p or Rad24p. Deletion of CTF18, CTF8, or DCC1 singly or in combination (ctf18Deltactf8Deltadcc1Delta) leads to sensitivity to microtubule depolymerizing drugs and a severe sister chromatid cohesion defect. Furthermore, temperature-sensitive mutations in RFC4 result in precocious sister chromatid separation. Our results highlight a novel function of the RFC proteins and support a model in which sister chromatid cohesion is established at the replication fork via a polymerase switching mechanism and a replication-coupled remodeling of chromatin.

  3. Effects of orally administered antioxidants on micronuclei and sister chromatid exchange frequency in workers professionally exposed to antineoplastic agents.

    Science.gov (United States)

    Mrđanović, Jasminka; Jungić, Saša; Šolajić, Slavica; Bogdanović, Višnja; Jurišić, Vladimir

    2012-08-01

    The widespread use of antineoplastic drugs in cancer treatment increased concern about possible hazard to workers involved in the preparation and administration of these drugs. In the present study, the effects of commercial antioxidative drug Oligogal Se on genome protection were analyzed in 15 nurses handling the antineoplastic drugs at the Oncology Department in comparison to twenty healthy volunteers. The nurses took antioxidant mixture Oligogal Se, consisting of vitamins C, E, A and selenium, one capsule per day, over a period of 6 months. Genome damage was measured in peripheral blood lymphocytes by usage of sister chromatid exchange test and the cytokinesis-block micronuclei test. The frequency of sister chromatid exchange (SCE) and micronuclei (MN) in the exposed group was significantly higher when compared to the control group (SCE, p<0.05; MN, p<0.01 respectively). After antioxidant supplementation, the frequency of sister chromatid exchange and micronuclei decreased (p<0.05) when compared with the values from the beginning of the study, but were still above the values of the control group. The effects of confounding factors such as cigarette smoking and cytostatics exposure time were also evaluated. The data indicated that Oligogal Se contributed to the decreasing of genome damages in workers handling the cytostatics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. RSC facilitates Rad59-dependent homologous recombination between sister chromatids by promoting cohesin loading at DNA double-strand breaks.

    Science.gov (United States)

    Oum, Ji-Hyun; Seong, Changhyun; Kwon, Youngho; Ji, Jae-Hoon; Sid, Amy; Ramakrishnan, Sreejith; Ira, Grzegorz; Malkova, Anna; Sung, Patrick; Lee, Sang Eun; Shim, Eun Yong

    2011-10-01

    Homologous recombination repairs DNA double-strand breaks by searching for, invading, and copying information from a homologous template, typically the homologous chromosome or sister chromatid. Tight wrapping of DNA around histone octamers, however, impedes access of repair proteins to DNA damage. To facilitate DNA repair, modifications of histones and energy-dependent remodeling of chromatin are required, but the precise mechanisms by which chromatin modification and remodeling enzymes contribute to homologous DNA repair are unknown. Here we have systematically assessed the role of budding yeast RSC (remodel structure of chromatin), an abundant, ATP-dependent chromatin-remodeling complex, in the cellular response to spontaneous and induced DNA damage. RSC physically interacts with the recombination protein Rad59 and functions in homologous recombination. Multiple recombination assays revealed that RSC is uniquely required for recombination between sister chromatids by virtue of its ability to recruit cohesin at DNA breaks and thereby promoting sister chromatid cohesion. This study provides molecular insights into how chromatin remodeling contributes to DNA repair and maintenance of chromatin fidelity in the face of DNA damage.

  5. Cis-acting determinants affecting centromere function, sister-chromatid cohesion and reciprocal recombination during meiosis in Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Sears, D.D.; Hieter, P. [Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States); Shero, J.H. [Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States)]|[Baylor College of Medicine, Houston, TX (United States); Hegemann, J.H. [Justus Liebig Universitaet, Giessen (Germany)

    1995-03-01

    We have employed a system that utilizes homologous pairs of human DNA-derived yeast artificial chromosomes (YACs) as marker chromosomes to assess the specific role(s) of conserved centromere DNA elements (CDEI, CDEII, and CDEIII) in meiotic chromosome disjunction fidelity. Thirteen different centromere (CEN) mutations were tested for their effects on meiotic centromere function. YACs containing a wild-type CEN DNA sequence segregate with high fidelity in meiosis I (99% normal segregation) and in meiosis II (96% normal segregation). YACs containing a 31-bp deletion mutation in centromere DNA element II (CDEII{Delta}31) in either a heterocentric (mutant/wild type), homocentric (mutant/mutant) or monosomic (mutant/-) YAC pair configuration exhibited high levels (16-28%) of precocious sister-chromatid segregation (PSS) and increased levels (1-6%) of nondisjunction meiosis I (NDI). YACs containing this mutation also exhibit high levels (21%) of meiosis II nondisjunction. Interestingly, significant alterations in homolog recombination frequency were observed in the exceptional PSS class of tetrads, suggesting unusual interactions between prematurely separated sister chromatids and their homologous nonsister chromatids. We also have assessed the meiotic segregation effects of rare gene conversion events occurring at sites located immediately adjacent to or distantly from the centromere region. Proximal gene conversion events were associated with extremely high levels (60%) of meiosis I segregation errors (including both PSS and NDI), whereas distal events had no apparent effect. Taken together, our results indicate a critical role for CDEII in meiosis and underscore the importance of maintaining sister-chromatid cohesion for proper recombination in meiotic prophase and for proper disjunction in meiosis I. 49 refs., 4 figs., 5 tabs.

  6. The Relationship between Dioxin Congeners in the Breast Milk of Vietnamese Women and Sister Chromatid Exchange

    Directory of Open Access Journals (Sweden)

    Hiroyuki Suzuki

    2014-04-01

    Full Text Available The aim of this study was to clarify the relationship between dioxin concentrations in breast milk and the sister chromatid exchange (SCE frequency in women from herbicide-sprayed and non sprayed areas. Blood samples were taken from 21 women with high TCDD (tetrachlorodibenzo-p-dioxin levels from sprayed areas, 23 women with moderate TCDD levels from sprayed areas, and 19 women from non sprayed areas to determine their SCE frequency. The SCE frequencies for the high and moderate TCDD groups from the sprayed area and for the non sprayed area group were 2.40, 2.19, and 1.48 per cell, respectively. Multiple regression analysis showed that the standardized β values for 1,2,3,6,7,8-hexaCDD (β = 0.60, 1,2,3,4,6,7,8-heptaCDD (β = 0.64, and octaCDD (β = 0.65 were higher than those for TCDD (β = 0.34 and 1,2,3,7,8-pentaCDD (β = 0.42. The adjusted R2 value for polyCDDs (R2 = 0.38 was higher than that for polyCDD toxic equivalents (TEQ (toxic equivalents; R2 = 0.23. This study therefore shows that levels of hexa-, hepta-, and octaCDD, which were previously regarded as being less toxic than TCDD, are closely related to SCE frequency and that the level of dioxin (pg/g lipid is potentially more useful as an indicator than TEQ value for explaining SCE frequency.

  7. A novel mechanism for the establishment of sister chromatid cohesion by the ECO1 acetyltransferase.

    Science.gov (United States)

    Guacci, Vincent; Stricklin, Jeremiah; Bloom, Michelle S; Guō, Xuánzōng; Bhatter, Meghna; Koshland, Douglas

    2015-01-01

    Cohesin complex mediates cohesion between sister chromatids, which promotes high-fidelity chromosome segregation. Eco1p acetylates the cohesin subunit Smc3p during S phase to establish cohesion. The current model posits that this Eco1p-mediated acetylation promotes establishment by abrogating the ability of Wpl1p to destabilize cohesin binding to chromosomes. Here we present data from budding yeast that is incompatible with this Wpl1p-centric model. Two independent in vivo assays show that a wpl1∆ fails to suppress cohesion defects of eco1∆ cells. Moreover, a wpl1∆ also fails to suppress cohesion defects engendered by blocking just the essential Eco1p acetylation sites on Smc3p (K112, K113). Thus removing WPL1 inhibition is insufficient for generating cohesion without ECO1 activity. To elucidate how ECO1 promotes cohesion, we conducted a genetic screen and identified a cohesion activator mutation in the SMC3 head domain (D1189H). Smc3-D1189H partially restores cohesion in eco1∆ wpl1∆ or eco1 mutant cells but robustly restores cohesion in cells blocked for Smc3p K112 K113 acetylation. These data support two important conclusions. First, acetylation of the K112 K113 region by Eco1p promotes cohesion establishment by altering Smc3p head function independent of its ability to antagonize Wpl1p. Second, Eco1p targets other than Smc3p K112 K113 are necessary for efficient establishment.

  8. Incorporation of deoxyuridine monophosphate into DNA increases the sister-chromatid exchange yield

    Energy Technology Data Exchange (ETDEWEB)

    Pardo, E.G.; Hernandez, P.; Gutierrez, C.

    1987-02-01

    The effect of a treatment with 5-fluoro-2'-deoxyuridine (FdUrd) in combination with 2'-deoxyuridine (dUrd) on cell proliferation, incorporation of DNA precursors into DNA and sister-chromatid exchanges (SCEs) has been analyzed in Allium cepa meristem cells. FdUrd in the range 10/sup -9/-5 x 10/sup -7/ M produced a dose- and time-dependent decrease in the amount of cells in mitosis. This inhibitory effect could be reversed by 70-80% in short-term (6 h) experiments, by exogenously supplied dUrd at a concentration of 10/sup -1/ M. However, at the highest FdUrd dose tested (10/sup -7/ M), 10/sup -4/ M dUrd could not reverse the FdUrd effect in long-term experiments as shown by analyzing the kinetics of synchronous cell populations. DNA extracted from cells pulsed with (6-/sup 3/H)dUrd in the presence of FdUrd and 6-amino-uracil (6-AU), an inhibitor of uracil-DNA glycosylase, contained a small amount of label in the form of (6-/sup 3/H)dUMP. Thus the authors conclude that under the experimental conditions, exogenously supplied dUrd may be metabolized intracellularly to 2'-deoxyuridine triphosphate (dUTP) and that this deoxynucleotide may eventually be mis-incorporated into DNA. By analyzing SCE levels in third division chromosomes of cells treated with FdUrd and dUrd during their second cycle, they has scored a 6-fold increase in the reciprocal SCE level which demonstrates that the replication of a dUMP-containing DNA template leads to a higher SCE yield.

  9. Diethylstilbestrol-diphosphate induces chromosomal aberrations but not sister chromatid exchanges in murine bone marrow cells in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Ivett, J.L. (North Carolina State Univ., Raleigh); Tice, R.R.

    1981-01-01

    Diethylstilbestrol diphosphate (DES-dp) clastogenesis was examined in the bone marrow of C57B1/6 male and female mice. Significant and sex-related dose effects were observed for the induction of chromatid-type chromosomal aberrations and for the inhibition of cellular proliferation. Females were more sensitive to the effects of DES-dp than males when assessed for either induced chromosomal aberrations or proliferative inhibition. Contrary to other published results, we did not observe either an increase in sister chromatid exchanges or an increased incidence of aneuploidy. Ovariectomy reduced the ability of DES-dp to inhibit cellular proliferation and decreased the high degree of variability between animals at high doses of DES-dp. The results of our studies show that DES is a clastogenic agent in vivo which may relate to its carcinogenicity.

  10. Chiasmata Promote Monopolar Attachment of Sister Chromatids and Their Co-Segregation toward the Proper Pole during Meiosis I

    Science.gov (United States)

    Ohba, Tatsunori; Hinohara, Yumi; Matsuhara, Hirotada; Yoshida, Masashi; Itabashi, Yuta; Murakami, Hiroshi; Yamamoto, Ayumu

    2011-01-01

    The chiasma is a structure that forms between a pair of homologous chromosomes by crossover recombination and physically links the homologous chromosomes during meiosis. Chiasmata are essential for the attachment of the homologous chromosomes to opposite spindle poles (bipolar attachment) and their subsequent segregation to the opposite poles during meiosis I. However, the overall function of chiasmata during meiosis is not fully understood. Here, we show that chiasmata also play a crucial role in the attachment of sister chromatids to the same spindle pole and in their co-segregation during meiosis I in fission yeast. Analysis of cells lacking chiasmata and the cohesin protector Sgo1 showed that loss of chiasmata causes frequent bipolar attachment of sister chromatids during anaphase. Furthermore, high time-resolution analysis of centromere dynamics in various types of chiasmate and achiasmate cells, including those lacking the DNA replication checkpoint factor Mrc1 or the meiotic centromere protein Moa1, showed the following three outcomes: (i) during the pre-anaphase stage, the bipolar attachment of sister chromatids occurs irrespective of chiasma formation; (ii) the chiasma contributes to the elimination of the pre-anaphase bipolar attachment; and (iii) when the bipolar attachment remains during anaphase, the chiasmata generate a bias toward the proper pole during poleward chromosome pulling that results in appropriate chromosome segregation. Based on these results, we propose that chiasmata play a pivotal role in the selection of proper attachments and provide a backup mechanism that promotes correct chromosome segregation when improper attachments remain during anaphase I. PMID:21423721

  11. Chiasmata promote monopolar attachment of sister chromatids and their co-segregation toward the proper pole during meiosis I.

    Directory of Open Access Journals (Sweden)

    Yukinobu Hirose

    2011-03-01

    Full Text Available The chiasma is a structure that forms between a pair of homologous chromosomes by crossover recombination and physically links the homologous chromosomes during meiosis. Chiasmata are essential for the attachment of the homologous chromosomes to opposite spindle poles (bipolar attachment and their subsequent segregation to the opposite poles during meiosis I. However, the overall function of chiasmata during meiosis is not fully understood. Here, we show that chiasmata also play a crucial role in the attachment of sister chromatids to the same spindle pole and in their co-segregation during meiosis I in fission yeast. Analysis of cells lacking chiasmata and the cohesin protector Sgo1 showed that loss of chiasmata causes frequent bipolar attachment of sister chromatids during anaphase. Furthermore, high time-resolution analysis of centromere dynamics in various types of chiasmate and achiasmate cells, including those lacking the DNA replication checkpoint factor Mrc1 or the meiotic centromere protein Moa1, showed the following three outcomes: (i during the pre-anaphase stage, the bipolar attachment of sister chromatids occurs irrespective of chiasma formation; (ii the chiasma contributes to the elimination of the pre-anaphase bipolar attachment; and (iii when the bipolar attachment remains during anaphase, the chiasmata generate a bias toward the proper pole during poleward chromosome pulling that results in appropriate chromosome segregation. Based on these results, we propose that chiasmata play a pivotal role in the selection of proper attachments and provide a backup mechanism that promotes correct chromosome segregation when improper attachments remain during anaphase I.

  12. Chromosome aberrations and sister chromatid exchanges in cultured human lymphocytes treated with sodium metabisulfite, a food preservative.

    Science.gov (United States)

    Rencüzogullari, E; Ila, H B; Kayraldiz, A; Topaktaş, M

    2001-02-20

    The aim of this study was to investigate the ability of sodium metabisulfite (SMB) which is used as an antimicrobial substance in food, to induce chromosome aberrations (CA) and sister chromatid exchanges (SCE) in human lymphocytes. SMB-induced CAs and SCEs at all concentrations (75, 150 and 300 microg/ml) and treatment periods (24 and 48h) dose-dependently. However, SMB decreased the replication index (RI) and the mitotic index (MI) at the concentrations of 150 and 300 microg/ml for 24 and 48h treatment periods. This decrease was dose-dependent as well.

  13. Rate of sister chromatid exchanges in Bloom syndrome fibroblasts reduced by co-cultivation with normal fibroblasts.

    OpenAIRE

    1980-01-01

    Six strains of Bloom syndrome (BlS) fibroblasts responded to co-cultivation with normal fibroblasts at a 1:2 ratio by a reduced rate of sister chromatid exchanges (SCE's) from a mean of 67.5 (range = 59--78) to 28.4 (range = 21--35). The response was dose-dependent in one strain tested at 1:2, 1:1, and 2:1 ratios. In addition, quadriradial exchange figures and other signs of increased chromosomal instability were not found in BlS cells following co-cultivation with control cells. Control cell...

  14. Variations in dysfunction of sister chromatid cohesion in esco2 mutant zebrafish reflect the phenotypic diversity of Roberts syndrome

    Directory of Open Access Journals (Sweden)

    Stefanie M. Percival

    2015-08-01

    Full Text Available Mutations in ESCO2, one of two establishment of cohesion factors necessary for proper sister chromatid cohesion (SCC, cause a spectrum of developmental defects in the autosomal-recessive disorder Roberts syndrome (RBS, warranting in vivo analysis of the consequence of cohesion dysfunction. Through a genetic screen in zebrafish targeting embryonic-lethal mutants that have increased genomic instability, we have identified an esco2 mutant zebrafish. Utilizing the natural transparency of zebrafish embryos, we have developed a novel technique to observe chromosome dynamics within a single cell during mitosis in a live vertebrate embryo. Within esco2 mutant embryos, we observed premature chromatid separation, a unique chromosome scattering, prolonged mitotic delay, and genomic instability in the form of anaphase bridges and micronuclei formation. Cytogenetic studies indicated complete chromatid separation and high levels of aneuploidy within mutant embryos. Amongst aneuploid spreads, we predominantly observed decreases in chromosome number, suggesting that either cells with micronuclei or micronuclei themselves are eliminated. We also demonstrated that the genomic instability leads to p53-dependent neural tube apoptosis. Surprisingly, although many cells required Esco2 to establish cohesion, 10-20% of cells had only weakened cohesion in the absence of Esco2, suggesting that compensatory cohesion mechanisms exist in these cells that undergo a normal mitotic division. These studies provide a unique in vivo vertebrate view of the mitotic defects and consequences of cohesion establishment loss, and they provide a compensation-based model to explain the RBS phenotypes.

  15. Variations in dysfunction of sister chromatid cohesion in esco2 mutant zebrafish reflect the phenotypic diversity of Roberts syndrome.

    Science.gov (United States)

    Percival, Stefanie M; Thomas, Holly R; Amsterdam, Adam; Carroll, Andrew J; Lees, Jacqueline A; Yost, H Joseph; Parant, John M

    2015-08-01

    Mutations in ESCO2, one of two establishment of cohesion factors necessary for proper sister chromatid cohesion (SCC), cause a spectrum of developmental defects in the autosomal-recessive disorder Roberts syndrome (RBS), warranting in vivo analysis of the consequence of cohesion dysfunction. Through a genetic screen in zebrafish targeting embryonic-lethal mutants that have increased genomic instability, we have identified an esco2 mutant zebrafish. Utilizing the natural transparency of zebrafish embryos, we have developed a novel technique to observe chromosome dynamics within a single cell during mitosis in a live vertebrate embryo. Within esco2 mutant embryos, we observed premature chromatid separation, a unique chromosome scattering, prolonged mitotic delay, and genomic instability in the form of anaphase bridges and micronuclei formation. Cytogenetic studies indicated complete chromatid separation and high levels of aneuploidy within mutant embryos. Amongst aneuploid spreads, we predominantly observed decreases in chromosome number, suggesting that either cells with micronuclei or micronuclei themselves are eliminated. We also demonstrated that the genomic instability leads to p53-dependent neural tube apoptosis. Surprisingly, although many cells required Esco2 to establish cohesion, 10-20% of cells had only weakened cohesion in the absence of Esco2, suggesting that compensatory cohesion mechanisms exist in these cells that undergo a normal mitotic division. These studies provide a unique in vivo vertebrate view of the mitotic defects and consequences of cohesion establishment loss, and they provide a compensation-based model to explain the RBS phenotypes.

  16. Unequal sister chromatid and homolog recombination at a tandem duplication of the A1 locus in maize.

    Science.gov (United States)

    Yandeau-Nelson, Marna D; Xia, Yiji; Li, Jin; Neuffer, M Gerald; Schnable, Patrick S

    2006-08-01

    Tandemly arrayed duplicate genes are prevalent. The maize A1-b haplotype is a tandem duplication that consists of the components, alpha and beta. The rate of meiotic unequal recombination at A1-b is ninefold higher when a homolog is present than when it is absent (i.e., hemizygote). When a sequence heterologous homolog is available, 94% of recombinants (264/281) are generated via recombination with the homolog rather than with the sister chromatid. In addition, 83% (220/264) of homolog recombination events involved alpha rather than beta. These results indicate that: (1) the homolog is the preferred template for unequal recombination and (2) pairing of the duplicated segments with the homolog does not occur randomly but instead favors a particular configuration. The choice of recombination template (i.e., homolog vs. sister chromatid) affects the distribution of recombination breakpoints within a1. Rates of unequal recombination at A1-b are similar to the rate of recombination between nonduplicated a1 alleles. Unequal recombination is therefore common and is likely to be responsible for the generation of genetic variability, even within inbred lines.

  17. Increased LOH due to Defective Sister Chromatid Cohesion Is due Primarily to Chromosomal Aneuploidy and not Recombination

    Directory of Open Access Journals (Sweden)

    Dror Sagi

    2017-10-01

    Full Text Available Loss of heterozygosity (LOH is an important factor in cancer, pathogenic fungi, and adaptation to changing environments. The sister chromatid cohesion process (SCC suppresses aneuploidy and therefore whole chromosome LOH. SCC is also important to channel recombinational repair to sister chromatids, thereby preventing LOH mediated by allelic recombination. There is, however, insufficient information about the relative roles that the SCC pathway plays in the different modes of LOH. Here, we found that the cohesin mutation mcd1-1, and other mutations in SCC, differentially affect the various types of LOH. The greatest effect, by three orders of magnitude, was on whole chromosome loss (CL. In contrast, there was little increase in recombination-mediated LOH, even for telomeric markers. Some of the LOH events that were increased by SCC mutations were complex, i.e., they were the result of several chromosome transactions. Although these events were independent of POL32, the most parsimonious way to explain the formation of at least some of them was break-induced replication through the centromere. Interestingly, the mcd1-1 pol32Δ double mutant showed a significant reduction in the rate of CL in comparison with the mcd1-1 single mutant. Our results show that defects in SCC allow the formation of complex LOH events that, in turn, can promote drug or pesticide resistance in diploid microbes that are pathogenic to humans or plants.

  18. Regulation of centromere localization of the Drosophila Shugoshin MEI-S332 and sister-chromatid cohesion in meiosis.

    Science.gov (United States)

    Nogueira, Cristina; Kashevsky, Helena; Pinto, Belinda; Clarke, Astrid; Orr-Weaver, Terry L

    2014-07-31

    The Shugoshin (Sgo) protein family helps to ensure proper chromosome segregation by protecting cohesion at the centromere by preventing cleavage of the cohesin complex. Some Sgo proteins also influence other aspects of kinetochore-microtubule attachments. Although many Sgo members require Aurora B kinase to localize to the centromere, factors controlling delocalization are poorly understood and diverse. Moreover, it is not clear how Sgo function is inactivated and whether this is distinct from delocalization. We investigated these questions in Drosophila melanogaster, an organism with superb chromosome cytology to monitor Sgo localization and quantitative assays to test its function in sister-chromatid segregation in meiosis. Previous research showed that in mitosis in cell culture, phosphorylation of the Drosophila Sgo, MEI-S332, by Aurora B promotes centromere localization, whereas Polo phosphorylation promotes delocalization. These studies also suggested that MEI-S332 can be inactivated independently of delocalization, a conclusion supported here by localization and function studies in meiosis. Phosphoresistant and phosphomimetic mutants for the Aurora B and Polo phosphorylation sites were examined for effects on MEI-S332 localization and chromosome segregation in meiosis. Strikingly, MEI-S332 with a phosphomimetic mutation in the Aurora B phosphorylation site prematurely dissociates from the centromeres in meiosis I. Despite the absence of MEI-S332 on meiosis II centromeres in male meiosis, sister chromatids segregate normally, demonstrating that detectable levels of this Sgo are not essential for chromosome congression, kinetochore biorientation, or spindle assembly. Copyright © 2014 Nogueira et al.

  19. Absence of an effect of lead acetate on sperm morphology, sister chromatid exchanges or on micronuclei formation in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Willems, M.I.; Immel, H.R.; de Schepper, G.G.; Dietrich, A.J.J.; Wibowo, A.A.E.; Zielhuis, R.L.

    1982-07-01

    The influence of lead on sperm morphology, sister chromatid exchanges or on micronuclei formation was studied on male rabbits after exposure to doses of 0, 0.25, and 0.50 mg lead acetate/kg body weight subcutaneously injected three times a week during 14 weeks, each on a group of five rabbits. At the end of exposure phase the lead in blood concentrations of the three groups of rabbits were 0.32, 2.57, and 2.97 ..mu..mol/l respectively. The results did not show any evidence of treatment related effects on sperm count or on morphologic abnormalities of the sperms, neither on the histopathology of the testis. Statistical analysis of the number of sister chromatid exchanges per metaphase in lymphocytes indicated no differences between the groups. Also no dose dependent effect was observed on the relative number of micronuclei in bone marrow erythrocytes. The different susceptibility to lead in different organ systems of the rabbits was discussed.

  20. The MCM-binding protein ETG1 aids sister chromatid cohesion required for postreplicative homologous recombination repair.

    Directory of Open Access Journals (Sweden)

    Naoki Takahashi

    2010-01-01

    Full Text Available The DNA replication process represents a source of DNA stress that causes potentially spontaneous genome damage. This effect might be strengthened by mutations in crucial replication factors, requiring the activation of DNA damage checkpoints to enable DNA repair before anaphase onset. Here, we demonstrate that depletion of the evolutionarily conserved minichromosome maintenance helicase-binding protein ETG1 of Arabidopsis thaliana resulted in a stringent late G2 cell cycle arrest. This arrest correlated with a partial loss of sister chromatid cohesion. The lack-of-cohesion phenotype was intensified in plants without functional CTF18, a replication fork factor needed for cohesion establishment. The synergistic effect of the etg1 and ctf18 mutants on sister chromatid cohesion strengthened the impact on plant growth of the replication stress caused by ETG1 deficiency because of inefficient DNA repair. We conclude that the ETG1 replication factor is required for efficient cohesion and that cohesion establishment is essential for proper development of plants suffering from endogenous DNA stress. Cohesion defects observed upon knockdown of its human counterpart suggest an equally important developmental role for the orthologous mammalian ETG1 protein.

  1. Further characterization of the genotoxicity of formaldehyde in vitro by the sister chromatid exchange test and co-cultivation experiments.

    Science.gov (United States)

    Neuss, Simone; Speit, Günter

    2008-09-01

    The induction of sister chromatid exchanges (SCE) was used to further characterize the genotoxic action of formaldehyde (FA) on cultured mammalian cells. FA induced SCE in V79 Chinese hamster cells and A549 human lung cells in a concentration-related manner. Addition of 5-bromodeoxyuridine (BrdUrd) for the differentiation of sister chromatids to visualize SCE 4 h after the FA treatment led to a clearly reduced induction of SCE in agreement with the repair kinetics of FA-induced DNA-protein cross-links. When A549 cells were treated with FA for 1 h and then co-cultivated with V79 cells in the presence of BrdUrd, a clear induction of SCE was measured in V79 cells. When the same experiment was performed including washing and change of medium after the FA treatment, no induction of SCE was measured in V79 cells. These results indicate that reactive FA remains in the cell culture medium for a longer time period despite the high reactivity of FA with macromolecules. However, FA that has entered a cell is not released and does not damage other cells. Possible implications for the mutagenicity of FA in vivo will be discussed.

  2. Rtt107 phosphorylation promotes localisation to DNA double-stranded breaks (DSBs and recombinational repair between sister chromatids.

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    Pranav Ullal

    Full Text Available Efficient repair of DNA double-stranded breaks (DSB requires a coordinated response at the site of lesion. Nucleolytic resection commits repair towards homologous recombination, which preferentially occurs between sister chromatids. DSB resection promotes recruitment of the Mec1 checkpoint kinase to the break. Rtt107 is a target of Mec1 and serves as a scaffold during repair. Rtt107 plays an important role during rescue of damaged replication forks, however whether Rtt107 contributes to the repair of DSBs is unknown. Here we show that Rtt107 is recruited to DSBs induced by the HO endonuclease. Rtt107 phosphorylation by Mec1 and its interaction with the Smc5-Smc6 complex are both required for Rtt107 loading to breaks, while Rtt107 regulators Slx4 and Rtt101 are not. We demonstrate that Rtt107 has an effect on the efficiency of sister chromatid recombination (SCR and propose that its recruitment to DSBs, together with the Smc5-Smc6 complex is important for repair through the SCR pathway.

  3. Rec8p, a meiotic recombination and sister chromatid cohesion phosphoprotein of the Rad21p family conserved from fision yeast to humans.

    NARCIS (Netherlands)

    S. Parisi; M.J. McKay (Michael); M. Molnar; M.A. Thompson (Anne); P.J. van der Spek (Peter); E. van Drunen-Schoenmaker; R. Kanaar (Roland); E. Lehmann; J.H.J. Hoeijmakers (Jan); J. Kohli

    1999-01-01

    textabstractOur work and that of others defined mitosis-specific (Rad21 subfamily) and meiosis-specific (Rec8 subfamily) proteins involved in sister chromatid cohesion in several eukaryotes, including humans. Mutation of the fission yeast Schizosaccharomyces pombe rec8 gene was previously shown to

  4. Rec8p, a meiotic recombination and sister chromatid cohesion phosphoprotein of the Rad21p family conserved from fision yeast to humans.

    NARCIS (Netherlands)

    S. Parisi; M.J. McKay (Michael); M. Molnar; M.A. Thompson (Anne); P.J. van der Spek (Peter); E. van Drunen-Schoenmaker; R. Kanaar (Roland); E. Lehmann; J.H.J. Hoeijmakers (Jan); J. Kohli

    1999-01-01

    textabstractOur work and that of others defined mitosis-specific (Rad21 subfamily) and meiosis-specific (Rec8 subfamily) proteins involved in sister chromatid cohesion in several eukaryotes, including humans. Mutation of the fission yeast Schizosaccharomyces pombe rec8 gene was previously shown to c

  5. SGO1 maintains bovine meiotic and mitotic centromeric cohesions of sister chromatids and directly affects embryo development.

    Directory of Open Access Journals (Sweden)

    Feng-Xia Yin

    Full Text Available Shugoshin (SGO is a critical factor that enforces cohesion from segregation of paired sister chromatids during mitosis and meiosis. It has been studied mainly in invertebrates. Knowledge of SGO(s in a mammalian system has only been reported in the mouse and Hela cells. In this study, the functions of SGO1 in bovine oocytes during meiotic maturation, early embryonic development and somatic cell mitosis were investigated. The results showed that SGO1 was expressed from germinal vesicle (GV to the metaphase II stage. SGO1 accumulated on condensed and scattered chromosomes from pre-metaphase I to metaphase II. The over-expression of SGO1 did not interfere with the process of homologous chromosome separation, although once separated they were unable to move to the opposing spindle poles. This often resulted in the formation of oocytes with 60 replicated chromosomes. Depletion of SGO1 in GV oocytes affected chromosomal separation resulting in abnormal chromosome alignment at a significantly higher proportion than in control oocytes. Knockdown of SGO1 expression significantly decreased the embryonic developmental rate and quality. To further confirm the function(s of SGO1 during mitosis, bovine embryonic fibroblast cells were transfected with SGO1 siRNAs. SGO1 depletion induced the premature dissociation of chromosomal cohesion at the centromere and along the chromosome arm giving rise to abnormal appearing mitotic patterns. The results of this study infer that SGO1 is involved in the centromeric cohesion of sister chromatids and chromosomal movement towards the spindle poles. Depletion of SGO1 causes arrestment of cell division in meiosis and mitosis.

  6. Frequencies of chromosomal aberrations and sister chromatid exchanges in the benthic worm Neanthes arenaceodentata exposed to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, F.L.; Rice, D.W. Jr., Moore, D.H.

    1984-07-01

    Traditional bioassays are unsuitable for assessing sublethal effects from ocean disposal of low-level radioactive waste because mortality and phenotypic responses are not anticipated. We compared the usefulness of chromosomal aberration and sister chromatid exchange (SCE) induction as measures of low-level radiation effects in a sediment-dwelling marine worm, Neanthes arenaceodentata. The SCEs, in contrast to chromosomal aberrations, do not alter the overall chromosome morphology and in mammalian cells appear to be a more sensitive indicator of DNA alterations caused by environmental mutagens. Newly hatched larvae were exposed to two radiation-exposure regimes of either x rays at a high dose rate of 0.7 Gy (70 rad)/min for as long as 5.5 min or to /sup 60/Co gamma rays at a low dose rate of from 4.8 x 10/sup -5/ to 1.2 x 10/sup -1/ Gy (0.0048 to 12 rad)/h for 24 h. After irradiation, the larvae were exposed to 3 x 10/sup -5/M bromodeoxyuridine (BrdUrd) for 28 h (x-ray-irradiated larvae) or for 54 h (/sup 60/Co-irradiated larvae). Larval cells were examined for the proportion of cells in first, second, and third or greater division. Frequencies of chromosomal aberrations and SCEs were determined in first and second division cells, respectively. Results from x-ray irradiation indicated that dose-related increases occur in chromosome and chromatid deletions, but a dose of equal or greater 2 Gy (equal to or greater than 200 rad) was required to observe a significant increase. Worm larvae receiving /sup 60/Co irradiation showed elevated SCE frequencies with a significant increase of 0.6 Gy (60 rad). We suggest that both SCEs and chromosomal aberrations may be useful for measuring effects on genetic material induced by radiation. 56 references, 7 figures, 9 tables.

  7. Defective sister chromatid cohesion is synthetically lethal with impaired APC/C function.

    Science.gov (United States)

    de Lange, Job; Faramarz, Atiq; Oostra, Anneke B; de Menezes, Renee X; van der Meulen, Ida H; Rooimans, Martin A; Rockx, Davy A; Brakenhoff, Ruud H; van Beusechem, Victor W; King, Randall W; de Winter, Johan P; Wolthuis, Rob M F

    2015-10-01

    Warsaw breakage syndrome (WABS) is caused by defective DDX11, a DNA helicase that is essential for chromatid cohesion. Here, a paired genome-wide siRNA screen in patient-derived cell lines reveals that WABS cells do not tolerate partial depletion of individual APC/C subunits or the spindle checkpoint inhibitor p31(comet). A combination of reduced cohesion and impaired APC/C function also leads to fatal mitotic arrest in diploid RPE1 cells. Moreover, WABS cell lines, and several cancer cell lines with cohesion defects, display a highly increased response to a new cell-permeable APC/C inhibitor, apcin, but not to the spindle poison paclitaxel. Synthetic lethality of APC/C inhibition and cohesion defects strictly depends on a functional mitotic spindle checkpoint as well as on intact microtubule pulling forces. This indicates that the underlying mechanism involves cohesion fatigue in response to mitotic delay, leading to spindle checkpoint re-activation and lethal mitotic arrest. Our results point to APC/C inhibitors as promising therapeutic agents targeting cohesion-defective cancers.

  8. Chromosome segregation: Samurai separation of Siamese sisters.

    Science.gov (United States)

    Glotzer, M

    1999-07-15

    How do cells ensure that sister chromatids are precisely partitioned in mitosis? New studies on budding yeast have revealed that sister chromatid separation at anaphase requires endoproteolytic cleavage of a protein that maintains the association between sister chromatids.

  9. Effects of chronic exposure to 2, 3, 7, 8,-tetrachlorodibenzo-p-dioxin on sister chromatid exchange levels in peripheral lymphocytes of the rhesus monkey

    Energy Technology Data Exchange (ETDEWEB)

    Lim, M.; Jacobson-Kram, D.; Bowman, R.E.; Williams, J.R.

    1987-01-01

    Frequencies of sister chromatid exchanges and chromosomal aberrations were examined in peripheral lymphocytes of Rhesus monkeys that had been fed a diet containing 25 parts per trillion 2,3,7,8-tetrachlorodibenzo-p-dioxin for a period of 4 years. When compared to non-exposed control animals, no significant differences were noted for either of these cytogenetic end points. In addition, there was not a significant difference in sister chromatid exchange response to a challenge dose of mitomycin C in cells from 2,3,7,8-tetrachlorodibenzo-p-dioxin exposed animals compared to controls. The results confirm the lack of genotoxic effects associated with 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure.

  10. Protection of halogenated DNA from strand breakage and sister-chromatid exchange induced by the topoisomerase I inhibitor camptothecin

    Energy Technology Data Exchange (ETDEWEB)

    Orta, Manuel Luis; Mateos, Santiago; Cantero, Gloria [Department of Cell Biology, Faculty of Biology, University of Seville (Spain); Wolff, Lisa J. [Sweet Briar College, VA (United States); Cortes, Felipe [Department of Cell Biology, Faculty of Biology, University of Seville (Spain)], E-mail: cortes@us.es

    2008-01-01

    The fundamental nuclear enzyme DNA topoisomerase I (topo I), cleaves the double-stranded DNA molecule at preferred sequences within its recognition/binding sites. We have recently reported that when cells incorporate halogenated nucleosides analogues of thymidine into DNA, it interferes with normal chromosome segregation, as shown by an extraordinarily high yield of endoreduplication, and results in a protection against DNA breakage induced by the topo II poison m-AMSA [F. Cortes, N. Pastor, S. Mateos, I. Dominguez, The nature of DNA plays a role in chromosome segregation: endoreduplication in halogen-substituted chromosomes, DNA Repair 2 (2003) 719-726; G. Cantero, S. Mateos, N. Pastor; F. Cortes, Halogen substitution of DNA protects from poisoning of topoisomerase II that results in DNA double-strand breaks (DSBs), DNA Repair 5 (2006) 667-674]. In the present investigation, we have assessed whether the presence of halogenated nucleosides in DNA diminishes the frequency of interaction of topo I with DNA and thus the frequency with which the stabilisation of cleavage complexes by the topo I poison camptothecin (CPT) takes place, in such a way that it protects from chromosome breakage and sister-chromatid exchange. This protective effect is shown to parallel a loss in halogen-substituted cells of the otherwise CPT-increased catalytic activity bound to DNA.

  11. Regulation of the Drosophila Enhancer of split and invected-engrailed gene complexes by sister chromatid cohesion proteins.

    Directory of Open Access Journals (Sweden)

    Cheri A Schaaf

    Full Text Available The cohesin protein complex was first recognized for holding sister chromatids together and ensuring proper chromosome segregation. Cohesin also regulates gene expression, but the mechanisms are unknown. Cohesin associates preferentially with active genes, and is generally absent from regions in which histone H3 is methylated by the Enhancer of zeste [E(z] Polycomb group silencing protein. Here we show that transcription is hypersensitive to cohesin levels in two exceptional cases where cohesin and the E(z-mediated histone methylation simultaneously coat the entire Enhancer of split and invected-engrailed gene complexes in cells derived from Drosophila central nervous system. These gene complexes are modestly transcribed, and produce seven of the twelve transcripts that increase the most with cohesin knockdown genome-wide. Cohesin mutations alter eye development in the same manner as increased Enhancer of split activity, suggesting that similar regulation occurs in vivo. We propose that cohesin helps restrain transcription of these gene complexes, and that deregulation of similarly cohesin-hypersensitive genes may underlie developmental deficits in Cornelia de Lange syndrome.

  12. Analysis of spontaneous and streptonigrin-induced sister chromatid exchanges in peripheral lymphocytes of aircrew members of international flights.

    Science.gov (United States)

    Sánchez, Julieta; Bianchi, Martha Susana; Ciancio, Vicente Rubén; Bolzán, Alejandro Daniel

    2008-01-01

    In this work, we extend our previous studies concerning mutagen sensitivity in flight personnel from commercial airlines by analyzing the frequency of spontaneous and streptonigrin (SN)-induced sister chromatid exchanges (SCEs) in peripheral blood lymphocytes of 18 long-haul aircrew members from Argentina and of 18 control individuals. Statistical analysis revealed no significant differences between aircrew and controls in the background level of SCEs (p > 0.05), which suggests that chronic exposure to cosmic radiation and other occupational hazards does not affect SCEs frequency in peripheral lymphocytes of aircrews. The fact that almost no correlation was found between cumulative flight hours and the yield of spontaneous SCEs in aircrews adds further support to this assumption. Therefore, the background SCEs frequency cannot be use as a valid biomarker to determine the genotoxic effects of cosmic radiation or other occupational hazards exposure in aircrews. Following SN treatment, a significant increase in the mean frequency of SCEs was observed in the control group (p aircrew group (p > 0.05), suggesting that at the population level, aircrew are more resistant to the mutagenic effects of SN than controls. The reasons of this resistance remain to be determined. Since cosmic radiation had no effect on the background SCEs frequency and no relationship was found between cumulative flight hours and SCEs inducer effect by SN in aircrews, a direct effect of cosmic radiation on SN resistance should be discarded.

  13. SNW1 enables sister chromatid cohesion by mediating the splicing of sororin and APC2 pre-mRNAs.

    Science.gov (United States)

    van der Lelij, Petra; Stocsits, Roman R; Ladurner, Rene; Petzold, Georg; Kreidl, Emanuel; Koch, Birgit; Schmitz, Julia; Neumann, Beate; Ellenberg, Jan; Peters, Jan-Michael

    2014-11-18

    Although splicing is essential for the expression of most eukaryotic genes, inactivation of splicing factors causes specific defects in mitosis. The molecular cause of this defect is unknown. Here, we show that the spliceosome subunits SNW1 and PRPF8 are essential for sister chromatid cohesion in human cells. A transcriptome-wide analysis revealed that SNW1 or PRPF8 depletion affects the splicing of specific introns in a subset of pre-mRNAs, including pre-mRNAs encoding the cohesion protein sororin and the APC/C subunit APC2. SNW1 depletion causes cohesion defects predominantly by reducing sororin levels, which causes destabilisation of cohesin on DNA. SNW1 depletion also reduces APC/C activity and contributes to cohesion defects indirectly by delaying mitosis and causing "cohesion fatigue". Simultaneous expression of sororin and APC2 from intron-less cDNAs restores cohesion in SNW1-depleted cells. These results indicate that the spliceosome is required for mitosis because it enables expression of genes essential for cohesion. Our transcriptome-wide identification of retained introns in SNW1- and PRPF8-depleted cells may help to understand the aetiology of diseases associated with splicing defects, such as retinosa pigmentosum and cancer.

  14. SA1 binds directly to DNA through its unique AT-hook to promote sister chromatid cohesion at telomeres.

    Science.gov (United States)

    Bisht, Kamlesh K; Daniloski, Zharko; Smith, Susan

    2013-08-01

    Sister chromatid cohesion relies on cohesin, a complex comprising a tri-partite ring and a peripheral subunit Scc3, which is found as two related isoforms SA1 and SA2 in vertebrates. There is a division of labor between the vertebrate cohesin complexes; SA1-cohesin is required at telomeres and SA2-cohesin at centromeres. Depletion of SA1 has dramatic consequences for telomere function and genome integrity, but the mechanism by which SA1-cohesin mediates cohesion at telomeres is not well understood. Here we dissect the individual contribution of SA1 and the ring subunits to telomere cohesion and show that telomeres rely heavily on SA1 and to a lesser extent on the ring for cohesion. Using chromatin immunoprecipitation we show that SA1 is highly enriched at telomeres, is decreased at mitosis when cohesion is resolved, and is increased when cohesion persists. Overexpression of SA1 alone was sufficient to induce cohesion at telomeres, independent of the cohesin ring and dependent on its unique (not found in SA2) N-terminal domain, which we show binds to telomeric DNA through an AT-hook motif. We suggest that a specialized cohesion mechanism may be required to accommodate the high level of DNA replication-associated repair at telomeres.

  15. Influence of retinol on carcinogen-induced sister chromatid exchangers and chromosome aberrations in V79 cells

    Energy Technology Data Exchange (ETDEWEB)

    Qin, S.; Batt, T.; Huang, C.C.

    1985-01-01

    The influence of retinol (Rol) on sister chromatid exchangers (SCE) in V79 cells induced by six indirect and two direct carcinogens, and on chromosome aberration (CA) in V79 cells induced by four indirect carcinogens were studied. The indirect carcinogens used were aflatoxin B/sub 1/ (AFB), cyclophosphamide (CPP), benzo(a)anthracene (BA), benzo(a)pyrene (BP), 9,10-dimethyl-1,2-benz(a)anthracene (DMBA), and 3-methylcholanthrene (MCA). The two direct carcinogens were ethyl methane sulfonate (EMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Rol effectively inhibited SCE and CA induced by AFB and CPP in a dose-dependent manner, but it had no effect on SCE induced by BA, BP, DMBA, MCA, EMS, and MNNG. To the contrary, Rol had an enhancing effect on CA induced by BP and DMBA. The possibility that Rol exerts its anticarcinogenic effects by inhibiting certain forms of the cytochrome P-450 isoenzymes required for activation of precarcinogens, such as AFB and CPP but not those enzymes required by BA, BP, DMBA, and MCA, is discussed.

  16. Sister chromatid exchange assessment by chromosome orientation-fluorescence in situ hybridization on the bovine sex chromosomes and autosomes 16 and 26.

    Science.gov (United States)

    Revay, T; King, W A

    2012-01-01

    Mammalian genome replication and maintenance are intimately coupled with the mechanisms that ensure cohesion between the resultant sister chromatids and the repair of DNA breaks. Although a sister chromatid exchange (SCE) is an error-free swapping of precisely matched and identical DNA strands, repetitive elements adjacent to the break site can act as alternative template sites and an unequal sister chromatid exchange can result, leading to structural variations and copy number change. Here we test the vulnerability for SCEs of the repeat-rich bovine Y chromosome in comparison with X, 16 and 26 chromosomes, using chromosome orientation-fluorescence in situ hybridization. The mean SCE rate of the Y chromosome (0.065 ± 0.029) was similar to that of BTA16 and BTA26 (0.065, 0.055), but was only approximately half of that of the X chromosome (0.142). As the chromosomal length affects the number of SCE events, we adjusted the SCE rates of the Y, 16, and 26 chromosomes to the length of the largest chromosome X resulting in very similar adjusted SCE (SCE(adj)) rates in all categories. Our results - based on 3 independent bulls - show that, although the cattle Y chromosome is a chest full of repeated elements, their presence and the documented activity of repeats in SCE formation does not manifest in significantly higher SCE(adj) rates and suggest the importance of the structural organization of the Y chromosome and the role of alternative mitotic DNA repair mechanisms.

  17. New functions of Ctf18-RFC in preserving genome stability outside its role in sister chromatid cohesion.

    Science.gov (United States)

    Gellon, Lionel; Razidlo, David F; Gleeson, Olive; Verra, Lauren; Schulz, Danae; Lahue, Robert S; Freudenreich, Catherine H

    2011-02-10

    Expansion of DNA trinucleotide repeats causes at least 15 hereditary neurological diseases, and these repeats also undergo contraction and fragility. Current models to explain this genetic instability invoke erroneous DNA repair or aberrant replication. Here we show that CAG/CTG tracts are stabilized in Saccharomyces cerevisiae by the alternative clamp loader/unloader Ctf18-Dcc1-Ctf8-RFC complex (Ctf18-RFC). Mutants in Ctf18-RFC increased all three forms of triplet repeat instability--expansions, contractions, and fragility--with effect over a wide range of allele lengths from 20-155 repeats. Ctf18-RFC predominated among the three alternative clamp loaders, with mutants in Elg1-RFC or Rad24-RFC having less effect on trinucleotide repeats. Surprisingly, chl1, scc1-73, or scc2-4 mutants defective in sister chromatid cohesion (SCC) did not increase instability, suggesting that Ctf18-RFC protects triplet repeats independently of SCC. Instead, three results suggest novel roles for Ctf18-RFC in facilitating genomic stability. First, genetic instability in mutants of Ctf18-RFC was exacerbated by simultaneous deletion of the fork stabilizer Mrc1, but suppressed by deletion of the repair protein Rad52. Second, single-cell analysis showed that mutants in Ctf18-RFC had a slowed S phase and a striking G2/M accumulation, often with an abnormal multi-budded morphology. Third, ctf18 cells exhibit increased Rad52 foci in S phase, often persisting into G2, indicative of high levels of DNA damage. The presence of a repeat tract greatly magnified the ctf18 phenotypes. Together these results indicate that Ctf18-RFC has additional important functions in preserving genome stability, besides its role in SCC, which we propose include lesion bypass by replication forks and post-replication repair.

  18. Human RECQ1 is a DNA damage responsive protein required for genotoxic stress resistance and suppression of sister chromatid exchanges.

    Directory of Open Access Journals (Sweden)

    Sudha Sharma

    Full Text Available BACKGROUND: DNA helicases are ubiquitous enzymes that unwind DNA in an ATP-dependent and directionally specific manner. Unwinding of double-stranded DNA is essential for the processes of DNA repair, recombination, transcription, and DNA replication. Five human DNA helicases sharing sequence similarity with the E. coli RecQ helicase have been identified. Three of the human RecQ helicases are implicated in hereditary diseases (Bloom syndrome, Werner syndrome, and Rothmund-Thomson syndrome which display clinical symptoms of premature aging and cancer. RECQ1 helicase is the most highly expressed of the human RecQ helicases; however, a genetic disease has yet not been linked to mutations in the RECQ1 gene, and the biological functions of human RECQ1 in cellular DNA metabolism are not known. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we report that RECQ1 becomes phosphorylated upon DNA damage and forms irradiation-induced nuclear foci that associate with chromatin in human cells. Depletion of RECQ1 renders human cells sensitive to DNA damage induced by ionizing radiation or the topoisomerase inhibitor camptothecin, and results in spontaneous gamma-H2AX foci and elevated sister chromatid exchanges, indicating aberrant repair of DNA breaks. Consistent with a role in homologous recombinational repair, endogenous RECQ1 is associated with the strand exchange protein Rad51 and the two proteins directly interact with high affinity. CONCLUSION/SIGNIFICANCE: Collectively, these results provide the first evidence for a role of human RECQ1 in the response to DNA damage and chromosomal stability maintenance and point to the vital importance of RECQ1 in genome homeostasis.

  19. Low doses of alpha particles do not induce sister chromatid exchanges in bystander Chinese hamster cells defective in homologous recombination

    Energy Technology Data Exchange (ETDEWEB)

    Nagasawa, H; Wilson, P F; Chen, D J; Thompson, L H; Bedford, J S; Little, J B

    2007-10-26

    We reported previously that the homologous recombinational repair (HRR)-deficient Chinese hamster mutant cell line irs3 (deficient in the Rad51 paralog Rad51C) showed only a 50% spontaneous frequency of sister chromatid exchange (SCE) as compared to parental wild-type V79 cells. Furthermore, when irradiated with very low doses of alpha particles, SCEs were not induced in irs3 cells, as compared to a prominent bystander effect observed in V79 cells (Nagasawa et al., Radiat. Res. 164, 141-147, 2005). In the present study, we examined additional Chinese hamster cell lines deficient in the Rad51 paralogs Rad51C, Rad51D, Xrcc2, and Xrcc3 as well as another essential HRR protein, Brca2. Spontaneous SCE frequencies in non-irradiated wild-type cell lines CHO, AA8 and V79 were 0.33 SCE/chromosome, whereas two Rad51C-deficient cell lines showed only 0.16 SCE/chromosome. Spontaneous SCE frequencies in cell lines defective in Rad51D, Xrcc2, Xrcc3, and Brca2 ranged from 0.23-0.33 SCE/chromosome, 0-30% lower than wild-type cells. SCEs were induced significantly 20-50% above spontaneous levels in wild-type cells exposed to a mean dose of 1.3 mGy of alpha particles (<1% of nuclei traversed by an alpha particle). However, induction of SCEs above spontaneous levels was minimal or absent after {alpha}-particle irradiation in all of the HRR-deficient cell lines. These data suggest that Brca2 and the Rad51 paralogs contribute to DNA damage repair processes induced in bystander cells (presumably oxidative damage repair in S-phase cells) following irradiation with very low doses of alpha particles.

  20. New functions of Ctf18-RFC in preserving genome stability outside its role in sister chromatid cohesion.

    Directory of Open Access Journals (Sweden)

    Lionel Gellon

    Full Text Available Expansion of DNA trinucleotide repeats causes at least 15 hereditary neurological diseases, and these repeats also undergo contraction and fragility. Current models to explain this genetic instability invoke erroneous DNA repair or aberrant replication. Here we show that CAG/CTG tracts are stabilized in Saccharomyces cerevisiae by the alternative clamp loader/unloader Ctf18-Dcc1-Ctf8-RFC complex (Ctf18-RFC. Mutants in Ctf18-RFC increased all three forms of triplet repeat instability--expansions, contractions, and fragility--with effect over a wide range of allele lengths from 20-155 repeats. Ctf18-RFC predominated among the three alternative clamp loaders, with mutants in Elg1-RFC or Rad24-RFC having less effect on trinucleotide repeats. Surprisingly, chl1, scc1-73, or scc2-4 mutants defective in sister chromatid cohesion (SCC did not increase instability, suggesting that Ctf18-RFC protects triplet repeats independently of SCC. Instead, three results suggest novel roles for Ctf18-RFC in facilitating genomic stability. First, genetic instability in mutants of Ctf18-RFC was exacerbated by simultaneous deletion of the fork stabilizer Mrc1, but suppressed by deletion of the repair protein Rad52. Second, single-cell analysis showed that mutants in Ctf18-RFC had a slowed S phase and a striking G2/M accumulation, often with an abnormal multi-budded morphology. Third, ctf18 cells exhibit increased Rad52 foci in S phase, often persisting into G2, indicative of high levels of DNA damage. The presence of a repeat tract greatly magnified the ctf18 phenotypes. Together these results indicate that Ctf18-RFC has additional important functions in preserving genome stability, besides its role in SCC, which we propose include lesion bypass by replication forks and post-replication repair.

  1. Effect of aging on superovulation efficiency, aneuploidy rates, and sister chromatid cohesion in mice aged up to 15 months.

    Science.gov (United States)

    Merriman, Julie A; Jennings, Phoebe C; McLaughlin, Eileen A; Jones, Keith T

    2012-02-01

    Human eggs are highly aneuploid, with female age being the only known risk factor. Here this aging phenomenon was further studied in Swiss CD1 mice aged between 1 and 15 mo. The mean number of eggs ± SEM recovered from mice following superovulation peaked at 22.5 ± 3.8 eggs/oviduct in 3-mo-old females, decreasing markedly between 6 and 9 mo old, and was only 2.1 ± 0.2 eggs/oviduct by 15 mo. Measurement of aneuploidy in these eggs revealed a low rate, ∼3-4%, in mice aged 1 and 3 mo, rising to 12.5% by 9 mo old and to 37.5% at 12 mo. Fifteen-month-old mice had the highest rate of aneuploidy, peaking at 60%. The in situ chromosome counting technique used here allowed us to measure with accuracy the distance between the kinetochores in the sister chromatids of the eggs analyzed for aneuploidy. We observed that this distance increased in eggs from older females, from 0.38 ± 0.01 μm at 1 mo old to 0.82 ± 0.03 μm by 15 mo. Furthermore, in 3- to 12-mo-old females, aneuploid eggs had significantly larger interkinetochore distances than euploid eggs from the same age, and measurements were similar to eggs from the oldest mice. However, the association between aneuploidy and interkinetochore distance was not observed at the oldest, 15-mo age, despite such measurements being maximal. We conclude that in aging CD1 mice, a reduction in the ovulated egg number precedes a rise in aneuploidy and, furthermore, except at very advanced ages, increased interkinetochore distance is associated with aneuploidy.

  2. A novel frameshift mutation in BLM gene associated with high sister chromatid exchanges (SCE) in heterozygous family members.

    Science.gov (United States)

    Ben Salah, Ghada; Hadj Salem, Ikhlas; Masmoudi, Abderrahmen; Kallabi, Fakhri; Turki, Hamida; Fakhfakh, Faiza; Ayadi, Hamadi; Kamoun, Hassen

    2014-11-01

    The Bloom syndrome (BS) is an autosomic recessive disorder comprising a wide range of abnormalities, including stunted growth, immunodeficiency, sun sensitivity and increased frequency of various types of cancer. Bloom syndrome cells display a high level of genetic instability, including a 10-fold increase in the sister chromatid exchanges (SCE) level. Bloom syndrome arises through mutations in both alleles of the BLM gene, which was identified as a member of the RecQ helicase family. In this study, we screened a Tunisian family with three BS patients. Cytogenetic analysis showed several chromosomal aberrations, and an approximately 14-fold elevated SCE frequency in BS cells. A significant increase in SCE frequency was observed in some family members but not reaching the BS patients values, leading to suggest that this could be due to the heterozygous profile. Microsatellite genotyping using four fluorescent dye-labeled microsatellite markers revealed evidence of linkage to BLM locus and the healthy members, sharing higher SCE frequency, showed heterozygous haplotypes as expected. Additionally, the direct BLM gene sequencing identified a novel homozygous frameshift mutation c.3617-3619delAA (p.K1207fsX9) in BS patients and a heterozygous BLM mutation in the family members with higher SCE frequency. Our findings suggest that this latter mutation likely leads to a reduced BLM activity explaining the homologous recombination repair defect and, therefore, the increase in SCE. Based on the present data, the screening of this mutation could contribute to the rapid diagnosis of BS. The genetic confirmation of the mutation in BLM gene provides crucial information for genetic counseling and prenatal diagnosis.

  3. Intersection between the regulators of sister chromatid cohesion establishment and maintenance in budding yeast indicates a multi-step mechanism.

    Science.gov (United States)

    Noble, Daniel; Kenna, Margaret A; Dix, Melissa; Skibbens, Robert V; Unal, Elçin; Guacci, Vincent

    2006-11-01

    Sister chromatid cohesion is established during S phase and maintained until anaphase. The cohesin complex (Mcd1p/Scc1p, Smc1p, Smc3p Irr1p/Scc3p in budding yeast) serves a structural role as it is required at all times when cohesion exists. Pds5p colocalizes temporally and spatially with cohesin on chromosomes but is thought to serve as a regulator of cohesion maintenance during mitosis. In contrast, Ctf7p/Eco1p is required during S phase for establishment but is not required during mitosis. Here we provide genetic and biochemical evidence that the pathways of cohesion establishment and maintenance are intimately linked. Our results show that mutants in ctf7 and pds5 are synthetically lethal. Moreover, over-expression of either CTF7 or PDS5 exhibits reciprocal suppression of the other mutant's temperature sensitivity. The suppression by CTF7 is specific for pds5 mutants as CTF7 over-expression increases the temperature sensitivity of an mcd1 mutant but has no effect on smc1 or smc3 mutants. Three additional findings provide new insights into the process of cohesion establishment. First, over-expression of ctf7 alleles deficient in acetylase activity exhibit significantly reduced suppression of the pds5 mutant but exacerbated toxicity to the mcd1 mutant. Second, using chromosome spreads and chromatin immuno-precipitation, we find either cohesin complex or Pds5p chromosomal localization is altered in ctf7 mutants. Finally, biochemical analysis reveals that Ctf7p and Pds5p coimmunoprecipitate, which physically links these regulators of cohesion establishment and maintenance. We propose a model whereby Ctf7p and Pds5p cooperate to facilitate efficient establishment by mediating changes in cohesin complex on chromosomes after its deposition.

  4. Mutagenicity in Salmonella and sister chromatid exchange in mice for 1,4-, 1,3-, 2,4-, and 3,4-dimethylphenanthrenes.

    Science.gov (United States)

    Sinsheimer, J E; Giri, A K; Hooberman, B H; Jung, K Y; Gopalaswamy, R; Koreeda, M

    1991-01-01

    The mutagenicity in Salmonella and in vivo sister chromatid exchange in the bone-marrow cells of mice was determined for 1,4-, 1,3-, 2,4-, and 3,4-dimethylphenanthrene (DMPh) with the objective to study the relative importance of substitution at the 1 and 4 positions of this series of methylated phenanthrenes. For both tests, 1,4- DMPh was decidedly more genotoxic than the remaining regioisomers. While the well recognized role of steric crowding in the bay region is a factor in this enhanced genotoxicity, equally important is substitution at the 1 position with its potential to inhibit detoxication through 9,10-diol formation.

  5. Mutagenicity in Salmonella and sister chromatid exchange in mice for 1,4-, and 1,3-, 2,4-, and 3,4-dimethylphenanthrenes

    Energy Technology Data Exchange (ETDEWEB)

    Sinsheimer, J.E.; Giri, A.K.; Hooberman, B.H.; Jung, K.Y.; Gopalaswamy, R.; Koreeda, M. (Univ. of Michigan, Ann Arbor (United States))

    1991-01-01

    The mutagenicity in Salmonella and in vivo sister chromatid exchange in the bone-marrow cells of mice was determined for 1,4-, 1,3-, 2,4-, and 3,4-dimethylphenanthrene (DMPh) with the objective to study the relative importance of substitution at the 1 and 4 positions of this series of methylated phenanthrenes. For both tests, 1,4-DMPh was decidedly more genotoxic than the remaining regioisomers. While the well recognized role of steric crowding in the bay region is a factor in this enhanced genotoxicity, equally important is substitution at the 1 position with its potential to inhibit detoxication through 9,10-diol formation.

  6. Increased sister chromatid cohesion and DNA damage response factor localization at an enzyme-induced DNA double-strand break in vertebrate cells.

    LENUS (Irish Health Repository)

    Dodson, Helen

    2009-10-01

    The response to DNA damage in vertebrate cells involves successive recruitment of DNA signalling and repair factors. We used light microscopy to monitor the genetic dependencies of such localization to a single, induced DNA double strand break (DSB) in vertebrate cells. We used an inducible version of the rare-cutting I-SceI endonuclease to cut a chromosomally integrated I-SceI site beside a Tet operator array that was visualized by binding a Tet repressor-GFP fusion. Formation of gamma-H2AX foci at a single DSB was independent of ATM or Ku70. ATM-deficient cells showed normal kinetics of 53Bp1 recruitment to DSBs, but Rad51 localization was retarded. 53Bp1 and Rad51 foci formation at a single DSB was greatly reduced in H2AX-null DT40 cells. We also observed decreased inter-sister chromatid distances after DSB induction, suggesting that cohesin loading at DSBs causes elevated sister chromatid cohesion. Loss of ATM reduced DSB-induced cohesion, consistent with cohesin being an ATM target in the DSB response. These data show that the same genetic pathways control how cells respond to single DSBs and to multiple lesions induced by whole-cell DNA damage.

  7. In vitro Antigenotoxicity of Ulva rigida C.Agardh (Chlorophyceae) Extract against Induction of Chromosome Aberration,Sister Chromatid Exchange and Micronuclei by Mutagenic Agent MMC

    Institute of Scientific and Technical Information of China (English)

    SERAP CELIKLER; GAMZE YILDIZ; OZGUR VATAN; RAHMI BILALOGLU

    2008-01-01

    To determine the in vitro possible clastogenic and cytotoxic activities of Uh,a rigida crude extracts (UP,E),and identify their antigenotoxic and protective effects on chemotherapeutic agent mitomycine-C (MMC).Methods Anti-clastogenic and anti-genotoxic activities of Ulva rigida crude extracts (URE) were studied using chromosome aberration (CA),sister chromatid exchange (SCE),and micronuclei (MN) tests in human lymphocytes cultured in vitro.Results The chromosome aberration,sister chromatid exchange or micronuclei tests showed that URE at concentrations of 10,20,and 40 μg/mL had no clastogenic activity in human lymphocyte cell culture.Three doses of URE significantly decreased the number of chromosomal aberrations and the frequencies of SCE and MN when compared with the culture treated with MMC (P<0.0001).Conclusion Although URE itself is not a clastogenic or cytotoxic substance,it possesses strong antigenotoxic,anti-clastogenic,and protective effects on MMC in vitro.

  8. Genotoxic biomonitoring study of population residing in pesticide contaminated regions in Göksu Delta: micronucleus, chromosomal aberrations and sister chromatid exchanges.

    Science.gov (United States)

    Ergene, Serap; Celik, Ayla; Cavaş, Tolga; Kaya, Filiz

    2007-10-01

    Pesticides are widely used throughout the world in agriculture to protect crops and in public health to control diseases. Nevertheless, exposure to pesticides represents a potential risk to humans. This paper describes a study of possible genetic damage in the people living in regions contaminated with complex mixture of pesticides in Göksu Delta. In this study, used methods were chromosomal aberration (CA), sister chromatid exchange analysis (SCE) in the peripheral blood lymphocytes, and micronucleus (MN) assay in the buccal epithelial cells. In the present investigation, 32 affected subjects consist of 16 smoking and 16 non-smokings and an equal number of control subjects were assessed for genome damage. Micronucleus (MN), Broken egg (BE), Karyorrhexis (KR), Karyolysis (KL) and Binucleus (BN) frequencies were higher in affected subjects than in controls. Smoking had a statistically significant effect on the Micronucleus, Karyorrhexis and Binucleus frequencies for both the control and the exposed group. Also smoking and exposure affected the frequency of sister chromatid exchange and chromosomal aberrations compared with control groups.

  9. Psoralen/UVA treatment and chromosomes. I. Aberrations and sister chromatid exchange in human lymphocytes in vitro and synergism with caffeine

    Energy Technology Data Exchange (ETDEWEB)

    Waksvik, H.; Brogger, A.; Stene, J.

    1977-09-22

    Treatment of human lymphocytes in vitro with trimethylpsoralen or 8-methoxypsoralen and UVA irradiation (PUVA) induced chromosome damage, mainly constrictions and gaps, but also breaks and exchanges, and increased the frequency of sister chromatid exchange (SCE). The localization of the chromosome aberrations was nonrandom. The coincidence of many PUVA hits with mercaptoenthanol hits suggests that PUVA may have other targets in the cell than the DNA, perhaps the folding proteins of the chromosomes and the nuclear membrane/chromatin attachment organelles. Caffeine increased in a synergistic way the chromosome aberration yield if added after PUVA treatment, but there was no effect when caffeine was present before and during PUVA treatment. The SCE frequency was increased in the presence of caffeine.

  10. In Vitro genotoxic and antigenotoxic studies of Thai Noni fruit juice by chromosomal aberration and sister chromatid exchange assays in human lymphocytes

    Directory of Open Access Journals (Sweden)

    Treetip Ratanavalachai

    2008-09-01

    Full Text Available The genotoxic and antigenotoxic effects of Noni fruit juice produced in Thailand have been studied in human lymphocytes for chromosome aberration assay and sister chromatid exchange (SCE assay in vitro. Treatment of Noni fruit juice(3.1-50 mg/ml alone for 3 h did not significantly induce chromosomal aberration or SCE (p<0.05. Noni fruit juice at 6.2 mg/ml is the optimum dose for cell survival and cell replication as demonstrated by the highest value of mitotic index and proliferation index (P.I.. Interestingly, pretreatment of Noni fruit juice at the same concentration of 6.2 mg/ml for 2 hfollowed by mitomycin C treatment at 3 μg/ml for 2 h significantly reduced SCE level induced by mitomycin C (p<0.05. However, these treatments did not show significant decrease in chromatid-type aberrations. Our data indicate that Thai Noni fruit juice is not genotoxic against human lymphocytes in vitro. In addition, pretreatment of Noni fruit juice at 6.2 mg/ml demonstrated no anticlastogenic effect while had some antigenotoxic effects as demonstrated by significant decrease in the SCE level induced by mitomycin C (p<0.05. Therefore, the optimum dose of Noni fruit juice used as a traditional medicine is required and needs to be studied further for the benefit of human health.

  11. INVESTIGATION OF DNA REPAIR BY SISTER CHROMATID EXCHANGE (SCE) ANALYSIS AND THE ALKALINE SINGLE CELL GEL ASSAY (SCG) IN MAMMALIAN GO-LYMPHOCYTES AFTER IN VITRO EXPOSURE TO ETHYLENE OXIDE (EO)

    Science.gov (United States)

    Investigation ofDNA Repair by Sister Chromatid Exchange (SCE) Analysis and the Alkaline Single Cell Gel Assay (SCG) in Mammalian Go-Lymphocytes after In Vitro Exposure to Ethylene Oxide (EO). EO is a large volume chemical used primarily as an intermediate in manufacturing...

  12. Enhanced stimulation of chromosomal translocations and sister chromatid exchanges by either HO-induced double-strand breaks or ionizing radiation in Saccharomyces cerevisiae yku70 mutants

    Energy Technology Data Exchange (ETDEWEB)

    Fasullo, Michael [Ordway Research Institute, 150 New Scotland Avenue, Albany, NY 12209 (United States)]. E-mail: mfasullo@ordwayresearch.org; St Amour, Courtney [Ordway Research Institute, 150 New Scotland Avenue, Albany, NY 12209 (United States); Zeng Li [Ordway Research Institute, 150 New Scotland Avenue, Albany, NY 12209 (United States)

    2005-10-15

    DNA double-strand break (DSB) repair occurs by homologous recombination (HR) or non-homologous endjoining (NHEJ). In Saccharomyces cerevisiae, expression of both MAT a and MAT{alpha} inhibits NHEJ and facilitates DSB-initiated HR. We previously observed that DSB-initiated recombination between two his3 fragments, his3-{delta}5' and his3-{delta}3'::HOcs is enhanced in haploids and diploids expressing both MAT a and MAT{alpha} genes, regardless of the position or orientation of the his3 fragments. Herein, we measured frequencies of DNA damage-associated translocations and sister chromatid exchanges (SCEs) in yku70 haploid mutants, defective in NHEJ. Translocation and SCE frequencies were measured in strains containing the same his3 fragments after DSBs were made directly at trp1::his3-{delta}3'::HOcs. Wild type and yku70 cells were also exposed to ionizing radiation and radiomimetic agents methyl methanesulfonate (MMS), phleomycin, and 4-nitroquinolone-1-oxide (4-NQO). Frequencies of X-ray-associated and DSB-initiated translocations were five-fold higher in yku70 mutants compared to wild type; however, frequencies of phleomycin-associated translocations were lower in the yku70 haploid mutant. Frequencies of DSB-initiated SCEs were 1.8-fold higher in the yku70 mutant, compared to wild type. Thus, DSB-initiated HR between repeated sequences on non-homologous chromosomes and sister chromatids occurs at higher frequencies in yku70 haploid mutants; however, higher frequencies of DNA damage-associated HR in yku70 mutants depend on the DNA damaging agent.

  13. Drosophila TDP-43 RNA-Binding Protein Facilitates Association of Sister Chromatid Cohesion Proteins with Genes, Enhancers and Polycomb Response Elements.

    Directory of Open Access Journals (Sweden)

    Amanda Swain

    2016-09-01

    Full Text Available The cohesin protein complex mediates sister chromatid cohesion and participates in transcriptional control of genes that regulate growth and development. Substantial reduction of cohesin activity alters transcription of many genes without disrupting chromosome segregation. Drosophila Nipped-B protein loads cohesin onto chromosomes, and together Nipped-B and cohesin occupy essentially all active transcriptional enhancers and a large fraction of active genes. It is unknown why some active genes bind high levels of cohesin and some do not. Here we show that the TBPH and Lark RNA-binding proteins influence association of Nipped-B and cohesin with genes and gene regulatory sequences. In vitro, TBPH and Lark proteins specifically bind RNAs produced by genes occupied by Nipped-B and cohesin. By genomic chromatin immunoprecipitation these RNA-binding proteins also bind to chromosomes at cohesin-binding genes, enhancers, and Polycomb response elements (PREs. RNAi depletion reveals that TBPH facilitates association of Nipped-B and cohesin with genes and regulatory sequences. Lark reduces binding of Nipped-B and cohesin at many promoters and aids their association with several large enhancers. Conversely, Nipped-B facilitates TBPH and Lark association with genes and regulatory sequences, and interacts with TBPH and Lark in affinity chromatography and immunoprecipitation experiments. Blocking transcription does not ablate binding of Nipped-B and the RNA-binding proteins to chromosomes, indicating transcription is not required to maintain binding once established. These findings demonstrate that RNA-binding proteins help govern association of sister chromatid cohesion proteins with genes and enhancers.

  14. Chromosomal aberrations, sister-chromatid exchanges, cells with high frequency of SCE, micronuclei and comet assay parameters in 1, 3-butadiene-exposed workers.

    Science.gov (United States)

    Srám, R J; Rössner, P; Peltonen, K; Podrazilová, K; Mracková, G; Demopoulos, N A; Stephanou, G; Vlachodimitropoulos, D; Darroudi, F; Tates, A D

    1998-11-09

    The association of occupational exposure to 1,3-butadiene (BD) and induction of cytogenetic damage in peripheral lymphocytes was studied in 19 male workers from a monomer production unit and 19 control subjects from a heat production unit. The exposure to BD was measured by passive personal monitors. The following biomarkers were used: chromosomal aberrations (CA), sister chromatid exchanges (SCE), cells with a high frequency of SCE (HFC), micronuclei, comet assay parameters like tail length (TL) and percentage of DNA in tail [T (%)] and polymorphisms of GSTM1 and GSTT1 genotypes. BD exposure with a median value of 0.53 mg/m3 (range: 0.024-23.0) significantly increased (a) the percentage of cells with chromosomal aberrations in exposed vs. control groups (3.11% vs. 2.03%, P<0.01), (b) the frequency of SCE per cell (6.96 vs. 4.87, P<0.001), and (c) the percentage of HFC (19.9% vs. 4.1%, P<0.001). BD exposure had no significant effects on formation of micronuclei and on comet assay parameters. Effect of smoking was observed only for HFC in BD-exposed group. GSTM1 genotype affected chromosomal aberrations in exposed group, while GSTT1 genotype affected chromosomal aberrations in controls. No effect of GSTM1 or GSTT1 genotypes was observed on any other biomarkers used.

  15. Promutagen activation of triazine herbicides metribuzin and ametryn through Vicia faba metabolism inducing sister chromatid exchanges in human lymphocytes in vitro and in V. faba root tip meristems.

    Science.gov (United States)

    Flores-Maya, Saúl; Gómez-Arroyo, Sandra; Calderón-Segura, María Elena; Villalobos-Pietrini, Rafael; Waliszewski, Stefan M; de la Cruz, Leticia Gómez

    2005-03-01

    The aim of our study was the induction of sister chromatid exchanges (SCE) in human lymphocytes in vitro and in root tip meristems of Vicia faba to evaluate the genotoxic effects of metribuzin and ametryn. Direct treatments of these herbicides on human lymphocytes in vitro applied 24 h after the beginning of culture did not induce SCE; however, they showed a cytotoxic effect in the cultures expressed as cellular death. On the contrary, when extracts of V. faba roots, treated for 4 h with metribuzin and ametryn (in vivo activation), were added to the lymphocyte cultures, SCEs were significantly induced with an asymptotic response. Negative responses appeared with the in vitro assays, in which metribuzin and ametryn were added directly to the 48 h lymphocyte cultures for 4 h. Nevertheless, in treatments in which the S10 metabolic mix was added, the SCE frequencies were significantly different to the control, although a concentration-response relationship was only observed with metribuzin. The results showed that both herbicides needed the V. faba metabolism to produce SCE in human lymphocyte cultures. Metribuzin and ametryn applied to V. faba root tip meristems for 4 h increased SCE frequency significantly, and a concentration-response relationship was observed with both herbicides.

  16. Induction of micronuclei and sister chromatid exchange in bone-marrow cells and abnormalities in sperm of Algerian mice (Mus spretus) exposed to cadmium, lead and zinc.

    Science.gov (United States)

    Tapisso, Joaquim Torres; Marques, Carla Cristina; Mathias, Maria da Luz; Ramalhinho, Maria da Graça

    2009-08-01

    As a consequence of human activities, large amounts of cadmium, lead and zinc are released in the environment, often simultaneously. The aim of this study was to investigate under experimental conditions the DNA damage induced in Algerian mice (Mus spretus) exposed to cadmium (Cd), lead (Pb) and zinc (Zn) separately, or in selected combinations. Three cytogenetic end points were considered: the frequencies of micronucleated cells (MN) and sister chromatid exchange (SCE) in the bone marrow and the frequency of sperm abnormalities. Mice were treated by intraperitoneal (i.p.) injections with 5 or 10 doses of aqueous solutions of cadmium acetate, lead acetate and zinc acetate in concentrations corresponding to 1/10 of the LD50, respectively, 21.5, 0.46 and 1.5 mg/kg bw. The control groups were injected in the same way with distilled water. With only one exception (Cd + Zn group treated with 5 doses), the results show a significant increase of MN in all groups for both treatments (5 and 10 doses). Similarly, the results concerning the SCE revealed a statistically significant increase in all treated animals, with the exception of the Zn group treated with 5 doses. The number of sperm abnormalities was significantly higher in animals treated with 5 doses, except in the group Pb + Zn. In animals treated with 10 doses the number of sperm abnormalities was always statistically higher compared with controls. This study indicates that cadmium, lead and zinc can induce MN, SCEs and sperm abnormalities in Algerian mice and that the clastogenic potential is dependent on the time of exposure and the interaction between the three elements, confirming the environmental damage that may result from the simultaneous action of several metals. Most relevant is the toxic potential for Zn, related with the dose, which may compromise its protective effect against other metal contaminations, such as cadmium.

  17. Genotoxic effects of a particular mixture of acetamiprid and alpha-cypermethrin on chromosome aberration, sister chromatid exchange, and micronucleus formation in human peripheral blood lymphocytes.

    Science.gov (United States)

    Kocaman, Ayşe Yavuz; Topaktaş, Mehmet

    2010-04-01

    The genotoxic effects of a particular mixture of acetamiprid (Acm, neonicotinoid insecticide) and alpha-cypermethrin (alpha-cyp, pyrethroid insecticide) on human peripheral lymphocytes were examined in vitro by chromosomal aberrations (CAs), sister chromatid exchange (SCE), and micronucleus (MN) tests. The human peripheral lymphocytes were treated with 12.5 + 2.5, 15 + 5, 17.5 + 7.5, and 20 + 10 microg/mL of Acm+alpha-cyp, respectively, for 24 and 48 h. The mixture of Acm+alpha-cyp induced the CAs and SCEs at all concentrations and treatment times when compared with both the control and solvent control and these increases were concentration-dependent in both treatment times. MN formation was significantly induced at 12.5 + 2.5, 15 + 5, 17.5 + 7.5, microg/mL of Acm+alpha-cyp when compared with both controls although these increases were not concentration-dependent. Binuclear cells could not be detected sufficiently in the highest concentration of the mixture (20 + 10 microg/mL) for both the 24- and 48-h treatment times. Mitotic index (MI), proliferation index (PI) and nuclear division index (NDI) significantly decreased because of the cytotoxic and cytostatic effects of the mixture, at all concentrations for two treatment periods. Significant decreases in MI and PI were concentration dependent at both treatment times. The decrease in NDI was also concentration-dependent at 48-h treatment period. In general, Acm+alpha-cyp inhibited nuclear division more than positive control, mitomycin C (MMC) and showed a higher cytostatic effect than MMC. Furthermore, in this article, the results of combined effects of Acm+alpha-cyp were compared with the results of single effects of Acm or alpha-cyp (Kocaman and Topaktas,2007,2009, respectively). In conclusion, the particular mixture of Acm+alpha-cyp synergistically induced the genotoxicity/cytotoxicity in human peripheral blood lymphocytes.

  18. Sister chromatid exchange and micronucleus frequency in human lymphocytes of 1,650 subjects in an Italian population: II. Contribution of sex, age, and lifestyle.

    Science.gov (United States)

    Barale, R; Chelotti, L; Davini, T; Del Ry, S; Andreassi, M G; Ballardin, M; Bulleri, M; He, J; Baldacci, S; Di Pede, F; Gemignani, F; Landi, S

    1998-01-01

    Sister chromatid exchange (SCE) and micronuclei (MN) analysis was carried out on 1,650 healthy individuals living in Pisa and in two nearby small cities, Cascina and Navacchio (Ca-Na). The effect of smoking on SCEs was linearly correlated with the number of cigarettes per day, and an increase of 7.3% SCEs was detectable for as few cigarettes as 1-10/day. Ex-smokers showed intermediate mean values of SCEs (8.09 +/- 1.88) in comparison with never smokers (7.54 +/- 1.61) and current smokers (8.45 +/- 1.94). Mean values of SCEs of ex-smokers decreased linearly with time of smoking cessation, reaching the mean values of never smokers within 8 years. The extent of SCE decrease was inversely proportional to the number of cigarettes previously smoked. No interaction between smoking habits and coffee or alcohol drinking on SCEs was observed. A borderline (P = 0.053) increase in mean SCE values in coffee drinkers (more than 3 cups/day) was found. The age effect on SCEs was remarkable in Ca-Na, but not in Pisa donors. Job type was not associated with significant modification of mean values of SCEs. Multiple logistic regression analysis revealed a statistically significant association between the proportion of high frequency cells (HCF) outliers and coffee consumption. Age and sex appeared to be by far the most important variables associated with modifications in MN frequency, which increased by 0.04 per thousand and 0.02 per thousand per year in males and females, respectively. Children and young donors (age students (+0.71 and +0.55 per thousand, respectively). Smoking did not determine any increase of MN frequency. A total lack of correlation (P = 0.913) between MN and SCEs was observed.

  19. Susceptibility to induction of chromosomal damage by metabolites of 1,3-butadiene and its relationship to 'spontaneous' sister chromatid exchange frequencies in human lymphocytes.

    Science.gov (United States)

    Wiencke, J K; Kelsey, K T

    1993-01-01

    Occupational exposure to butadiene is associated with the occurrence of lymphohaematopoietic cancers. The mutagenicity of butadiene is thought to be mediated by its mono- and diepoxide metabolites, which are capable of binding to DNA. Diepoxybutane is the most potent genotoxic metabolite and is known to produce interstrand DNA cross-links. In order to study individual differences in response to the genotoxicity of diepoxybutane, we devised a human lymphocyte culture system that involves short-term culture of T lymphocytes and measurement of sister chromatid exchange (SCE) and chromosomal aberration frequency as genotoxic end-points. We observed that when lymphocytes from healthy individuals are exposed in vitro to 6 microM of diepoxybutane, the number of SCEs induced is distributed bimodally: about 20% of 173 healthy workers studied were twice as sensitive to the induction of SCEs as the remaining 80%. Cells from sensitive individuals also contain four times more diepoxybutane-induced chromosomal deletions and exchanges. Of particular interest is the observation that diepoxybutane-sensitive individuals have higher frequencies of baseline (i.e., uninduced) SCEs. We have now examined the sensitivity of individual lymphocytes to SCE induction by another DNA cross-linking agent (nitrogen mustard) and to monoepoxybutene. The results indicate that lymphocytes sensitive to diepoxybutane-induced SCEs have normal sensitivity to nitrogen mustard and a moderately increased response to the monofunctional agent monoepoxybutene. Measurement of diepoxybutane-induced SCEs is a potential biomarker of sensitivity to the genotoxic effects of butadiene and may be useful in occupational epidemiological studies. Such studies, in combination with measures of butadiene metabolism, could be useful in ascertaining whether the sensitivity is mediated by enzyme polymorphisms.

  20. Targeting of chemical mutagens to differentiating B-lymphocytes in vivo: detection by direct DNA labeling and sister chromatid exchange induction

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, S.E.; Nanna, U.C.; Dietert, R.R.

    1987-01-01

    In vivo systems for analyzing mutagen interactions with a specific differentiating cell population are rare. Taking advantage of the unique anatomical features of the bursa of Fabricius in the chicken, the authors explored the possibility of targeting chemical mutagens to a defined differentiating cell population in the animal, namely, the B-lymphocytes series. Such cells are known to be the targets for the oncogene-activating avian leukosis virus. Targeting of chemicals to cells of the bursa was demonstrated by application of the DNA-specific fluorochrome 4'-6-diamidino-2-phenylindole (DAPI) to the anal lips of neonatal chicks. Bright nuclear fluorescence of cells in the bursa demonstrated to occur within minutes after the application of 500..mu..l of DAPI. DAPI labeling of nuclei was detected up to several days after a single application. No nuclear labeling was exhibited in cells of neighboring tissues. Methyl methanesulfonate (MMS)(10..mu..l) was applied to the anal lips of day-old chicks to study dose-response kinetics for mutagen targeting to DNA of dividing B-lymphocytes in the bursa. Since the mitotic index was found to be quite high (25-30%) in the bursa, chromosome analysis was used to assay for genome damage. Sister chromatid exchange frequencies of 3.9, 7.3, and 9.0 (baseline 2.5) per cell were obtained at MMS dosages per animal of 50 ..mu..g, 100..mu..g, and 200..mu..g, respectively. These results indicate the rapid and quantitative localization of DNA-binding chemicals to cells of the bursa, particularly the resident B-lymphocytes. The bursa should be a useful system for studying mutagen-DNA interactions in the differentiating B-lymphocyte and subsequent influences on the development of immunity and lymphoproliferative disease.

  1. Reduction of diepoxybutane-induced sister chromatid exchanges by glutathione peroxidase and erythrocytes in transgenic Big Blue mouse and rat fibroblasts.

    Science.gov (United States)

    Erexson, G L; Tindall, K R

    2000-02-14

    We have investigated the effect of glutathione peroxidase (GSH-Px) and mammalian erythrocytes (RBCs) on spontaneous and diepoxybutane (DEB)-induced sister chromatid exchange (SCE) in primary Big Blue(R) mouse (BBM1) and Big Blue(R) rat (BBR1) fibroblasts. DEB is the putative carcinogenic metabolite of 1,3-butadiene (BD) for which inhalation exposure yields a high rate of malignancies in mice but not in rats. BD is metabolized differently in mice and rats, producing much higher levels of DEB in mice than in rats, which may partly explain the different carcinogenic responses. However, other factors may contribute to the observed differences in the rodent carcinogenic response to BD. DEB is a highly reactive compound. Upon epoxide hydrolysis, DEB can covalently bind to DNA bases. Likewise, DEB generates reactive oxygen species that, in turn, can either damage DNA or produce H(2)O(2). Reduced glutathione (GSH) is known to play a role in the metabolism and detoxification of DEB; and GSH is reduced by GSH-Px in the presence of H(2)O(2). GSH-Px is a constitutive enzyme that is found at high concentrations in mammalian RBCs. Therefore, we were interested in examining the role of RBCs and GSH-Px on DEB-induced SCE in rat and mouse cells for detection of possible differences in the species response. Transgenic BBM1 and BBR1 fibroblasts were treated with either 0, 2 or 4 microM DEB plus 0, 2 or 20 units of GSH-Px with and without 2x10(8) species-specific RBCs. DEB effectively induced SCEs in both rat and mouse cells. The relative induction of SCEs in both cell types was comparable. Both GSH-Px and RBCs alone and in combination were effective in significantly reducing DEB-induced SCEs in both mouse and rat fibroblasts, although there was more variability in the SCE response in rat cells. The present study suggests that GSH-Px may be important in the detoxification of DEB-induced DNA damage that results in the formation of SCEs.

  2. Evaluation of the persistence in the induction of Sister Chromatid Exchanges (SCE) by alkylating agents; Evaluacion de la persistencia en la induccion de Intercambio en las Cromatidas Hermanas (ICH) por agentes alquilantes

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez R, R.; Huerta V, C.; MOrales R, P.R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2006-07-01

    The persistence in the induction of sister chromatid exchanges (SCE) by the alkylating agents methyl and ethyl-methanesulfonates (MMS and EMS) was evaluated. For it, to groups of mice its were administered a dose of these agents and later its were analyzed the induced SCE's in two periods: early and late. Both agents caused high increments of SCE in the early period and small in the late one; however, the caused lately by EMS was significantly bigger. This late induction of SCE by EMS possibly is associated with an epigenetic change or with the presence of etiladucts in the phosphodiester bonds of the DNA. (Author)

  3. Investigation of Homologous Crossing over and Sister Chromatid Exchange in the Wheat Nor-B2 Locus Coding for Rrna and Gli-B2 Locus Coding for Gliadins

    Science.gov (United States)

    Dvořák, J.; Appels, R.

    1986-01-01

    Recombination was investigated within the Nor-B2 locus of wheat chromosome 6B that contains several thousand of the 18S-5.8S-26S rRNA (rDNA) repeated units. Additionally, recombination was assessed for several chromosome regions, in arm 6Bq between the centromere and the B2 locus (awn suppressor) and in arm 6Bp between the centromere and Nor-B2, between Nor-B2 and a distal C-band and between Nor-B2 and Gli-B2 coding for gliadins. The experimental design permitted the distinction between crossing over between homologous chromosomes and exchange between sister chromatids. No homologous crossing over within the Nor-B2 locus was found in a sample of 446 chromosomes, but one exchange with the attributes of unequal sister chromatid exchange was identified. The molecular characteristics of this presumed sister chromatid exchange indicate that the spacer variants present in the Nor-B2 locus are clustered. No homologous recombination was detected within the distal Gli-B2 locus containing repeated genes coding for gliadin seed-storage proteins. Both arms of chromosome 6B showed low crossing-over frequency in the proximal regions. The distance from the centromere to Nor-B2 was only from 0.3 to 2.2 cM although it accounts for about two-thirds of the metaphase chromosome arm, which shows a great distortion of the metaphase map of the arm. The level of homologous recombination within the Nor-B2 locus is lower than in the chromosome region immediately distal to it. Whether it is comparable to that in the chromosome region proximal to it could not be determined. Recombination frequencies of different pairs of chromosome 6B in all but one interval paralleled the frequencies of their metaphase I pairing: Lower pairing at metaphase I was paralleled by lower crossing-over frequency. This relationship indicated that reduced metaphase I pairing between 6B chromosomes from different populations is due to impaired crossing-over and not due to precocious chiasma terminalization. PMID

  4. Evidence that cyclophosphamide can to induce exchanges in the sister chromatids (ICH) through secondary injuries; Evidencia de que la ciclofosfamida puede inducir intercambios en las cromatidas hermanas (ICH) a traves de lesiones secundarias

    Energy Technology Data Exchange (ETDEWEB)

    Morales R, P.; Rodriguez R, R. [Instituto Nacional de Investigaciones nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    By means of the use of destination protocol of ICH inductive injuries (DLI-ICH), it was studied if interchanges in the sister chromatids (ICH) induced by cyclophosphamide (CP), in the second post-treatment division (ICH-2) are produced by secondary injuries or by fresh injuries. For discard between these possibilities it was administered CP at different periods before of the first post-treatment division, taking as reference the administered time for high dose of bromodeoxyuridine (BrdU ) which was approximately at the beginning of this division. The ICH frequencies that occur in the first, the second and the third synthesis stages (S) were determined. It was observed that when the administered CP was four hours before BrdU , the ICH frequencies of the second and the third S were reduced. The frequency of the first ICH increased lightly in relation to those of the normal protocol (0.5 h before BrdU ) and that the supplying of CP six hours before caused almost a total reduction of ICH of second and third S and an important increment of ICH of first S.This was interpreted as evidence that the ICH-2 are product of secondary injuries. (Author)

  5. Relationship of the demethylation of the DNA with the induction of the sister chromatid exchanges (SCE) In vivo; Relacion de la desmetilacion del ADN con la induccion de intercambios en las cromatidas hermanas (ICH) In vivo

    Energy Technology Data Exchange (ETDEWEB)

    Toribio E, E

    2005-07-01

    The methylation of the DNA is an epigenetic modification that has an important paper in the regulation of the functionality of the genome of the organisms. It can be altered by demethylation processes, either natural or experimentally induced. The 5-azacytidine (Aza) is a compound that causes the demethylation of the DNA (dm-DNA), inducing with it, expression genic and increase in the frequency of the Sister Chromatid Exchange (SCE). The SCE is a genotoxicity indicator, caused by diverse mutagens and carcinogen. Since the biological meaning and the formation mechanism of this phenomenon has not been totally illustrious, the exploration of the relation between the dm-DNA and the induction of SCE, it could offer new knowledge to explain those queries. The purpose of this work was to study in cells of the mouse bone marrow In vivo, the effect of the Aza on the induction of SCE, based on two aspects: 1) dose answer and 2) the effectiveness of multiple exhibition. To six groups of three to five animals, they are administered Aza to dose of 5, 10, 15 or 20 mg/Kg of weight; in sharp or multiple form, previously to the bromodeoxyuridine supply and 24 h was sacrificed after this; 2 h after an injection with colchicine. Preparations of those metaphases were made, those which were dyed by means of a technique of fluorescence more Giemsa. It was observed that to sharp low dose, the Aza produced an increment in the frequency of SCE that although small it was proportional and statistically significant. To sharp and multiple high doses, the Aza doesn't cause additional increments of SCE, but if toxicity at cellular level and of individuals. It is concluded that a relationship exists between the dm-DNA and the induction of SCE. It is suggested that the total demethylation of the DNA causes 2 SCE/Cell in cells of the mouse bone marrow, or that the cytotoxicity prevents to evidence a bigger induction. (Author)

  6. Role of oxidative stress and intracellular calcium in nickel carbonate hydroxide-induced sister-chromatid exchange, and alterations in replication index and mitotic index in cultured human peripheral blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    M' Bemba-Meka, Prosper [Universite de Montreal, Human Toxicology Research Group (TOXHUM), Department of Environmental and Occupational Health, Main Station, P.O. Box 6128, Montreal, QC (Canada); University of Louisville, Department of Pharmacology and Toxicology, Center for Genetics and Molecular Medicine, Louisville, KY (United States); Lemieux, Nicole [Universite de Montreal, Department of Pathology and Cellular Biology, Faculty of Medicine, Main Station, P.O. Box 6128, Montreal, QC (Canada); Chakrabarti, Saroj K. [Universite de Montreal, Human Toxicology Research Group (TOXHUM), Department of Environmental and Occupational Health, Main Station, P.O. Box 6128, Montreal, QC (Canada)

    2007-02-15

    Human peripheral lymphocytes from whole blood cultures were exposed to either soluble form of nickel carbonate hydroxide (NiCH) (0-60 {mu}M), or of nickel subsulfide (Ni{sub 3}S{sub 2}) (0-120 {mu}M), or of nickel oxide (NiO) (0-120 {mu}M), or nickel sulfate (NiSO{sub 4}) (0-120 {mu}M) for a short duration of 2 h. The treatments occurred 46 h after the beginning of the cultures. The cultures were harvested after a total incubation of 72 h, and sister-chromatid exchange (SCE), replication index (RI), and mitotic index (MI) were measured for each nickel compound. The soluble form of NiCH at 30 {mu}M but those of Ni{sub 3}S{sub 2} and NiO at 120 {mu}M produced significant increase in the SCE per cell compared to the control value, whereas NiSO{sub 4} failed to produce any such significant increase. Except NiSO{sub 4}, the soluble forms of NiCH, Ni{sub 3}S{sub 2}, and NiO produced significant cell-cycle delay (as measured by the inhibition of RI) as well as significant inhibition of the MI at respective similar concentrations as mentioned above. Pretreatment of human blood lymphocytes with catalase (H{sub 2}O{sub 2} scavenger), or superoxide dismutase (superoxide anion scavenger), or dimethylthiourea (hydroxyl radical scavenger), or deferoxamine (iron chelator), or N-acetylcysteine (general antioxidant) inhibited NiCH-induced SCE, and changes in RI and MI. This suggests the participation of oxidative stress involving H{sub 2}O{sub 2}, the superoxide anion radical, the hydroxyl radical, and iron in the NiCH-induced genotoxic responses. Cotreatment of NiCH with either verapamil (inhibitor of intracellular calcium ion ([Ca{sup 2+}]{sub i}) movement through plasma membranes), or dantrolene (inhibitor of [Ca{sup 2+}]{sub i} release from sarcoplasmic reticulum), or BAPTA (Ca{sup 2+} chelator) also inhibited the NiCH-induced responses. These results suggest that [Ca{sup 2+}]{sub i} is also implicated in the genotoxicity of NiCH. Overall these data indicate that various types

  7. Holocentric plant meiosis: first sisters, then homologues.

    Science.gov (United States)

    Heckmann, Stefan; Schubert, Veit; Houben, Andreas

    2014-01-01

    Meiosis is a crucial process of sexual reproduction by forming haploid gametes from diploid precursor cells. It involves 2 subsequent divisions (meiosis I and meiosis II) after one initial round of DNA replication. Homologous monocentric chromosomes are separated during the first and sister chromatids during the second meiotic division. The faithful segregation of monocentric chromosomes is realized by mono-orientation of fused sister kinetochores at metaphase I and by bi-orientation of sister kinetochores at metaphase II. Conventionally this depends on a 2-step loss of cohesion, along chromosome arms during meiosis I and at sister centromeres during meiosis II.

  8. The chromosome damage induced by x-ray radiation doses. Comparison between dicentric chromosomes, micronuclei and Sister Chromatid Exchanges analyses. Valoracion de dao cromosomico originado por una dosis de rayos X. Comparacion de los analisis de cromosomas dicentricos, micronucleos e intercambios entre cromatidas hermanas

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, J.L.; Losada, C.; Losada, G.; Veiras, C. (Centro Oncologico de Galicia. La Corua (Spain)); Goyanes, V.J. (Hospital ' ' Teresa Herrera' ' . La Corua (Spain))

    1993-01-01

    Exposure to ionizing radiations is a well-known source of chromosome damage. Here we present a comparison among three different methodologies employed to recognize cytogenetic damage, after an acute exposure of human lymphocytes to 3 Gy of X-rays (100kVp). Scoring of dicentric chromosomes, present in first mitosis ''in vitro'', was the method of preference as dicentrics increased 937.5 times with respect to background. Micronucleus scoring in binucleated-cytokinesis blocked cells showed an increase of 32.5 times, while it was only of 1.46 times when Sister Chromatid Exchanges (SCEs) were analyzed. The estimated probability of an acentric fragment becoming a micronucleus was around 0.25. Intercellular distribution of dicentrics agree with Poisson, while micronucleus were overdispersed. When analyzed at second cycle after damage induction, the dicentrics yield as well as the level of cells with unstable cromosome aberrations, decreased around a half. Finally, SCEs level was similar in cells with or without unstable structural chromosome aberrations. (Author)

  9. Sister kinetochores are mechanically fused during meiosis I in yeast.

    Science.gov (United States)

    Sarangapani, Krishna K; Duro, Eris; Deng, Yi; Alves, Flavia de Lima; Ye, Qiaozhen; Opoku, Kwaku N; Ceto, Steven; Rappsilber, Juri; Corbett, Kevin D; Biggins, Sue; Marston, Adèle L; Asbury, Charles L

    2014-10-10

    Production of healthy gametes requires a reductional meiosis I division in which replicated sister chromatids comigrate, rather than separate as in mitosis or meiosis II. Fusion of sister kinetochores during meiosis I may underlie sister chromatid comigration in diverse organisms, but direct evidence for such fusion has been lacking. We used laser trapping and quantitative fluorescence microscopy to study native kinetochore particles isolated from yeast. Meiosis I kinetochores formed stronger attachments and carried more microtubule-binding elements than kinetochores isolated from cells in mitosis or meiosis II. The meiosis I-specific monopolin complex was both necessary and sufficient to drive these modifications. Thus, kinetochore fusion directs sister chromatid comigration, a conserved feature of meiosis that is fundamental to Mendelian inheritance. Copyright © 2014, American Association for the Advancement of Science.

  10. Sisters Hope

    DEFF Research Database (Denmark)

    Lawaetz, Anna; Worre Hallberg, Gry

    2011-01-01

    Sisters Hope invites young scholars to visit our elite-school for run-away youngsters. Maybe you will be the next one to be collected and accepted?......Sisters Hope invites young scholars to visit our elite-school for run-away youngsters. Maybe you will be the next one to be collected and accepted?...

  11. Sisters Hope

    DEFF Research Database (Denmark)

    Lawaetz, Anna; Worre Hallberg, Gry

    2011-01-01

    I denne artikel indføres læseren i fiktionsuniverset og læringsmetoden Sisters Hope, der er inspireret af en ny tendens indenfor performancekunsten, som vi kalder "levende og relationelle fiktive paralleluniverser". Især udfoldes forskydningen af lærer- og elevrollen indenfor Sisters Hopes absurd...

  12. My sister

    Institute of Scientific and Technical Information of China (English)

    胡琪

    2004-01-01

    I have a sister.Her name is Deng Zi Jun.She's five years old.She has two big eyes,a small high nose and a small mouth.Her hair is short and black. My sister is a good student. She is good at Maths and Art.Sheis not very good at English.She likes watching TV,singing,drawing,eating,sleep-ing and playing.

  13. 石油作业女性染色单体交换与习惯性流产关系研究%Study on the relationship between sister chromatid exchange and habitual abortion among the women in the petroleum operations

    Institute of Scientific and Technical Information of China (English)

    慕明涛; 霍满鹏; 蒲力群; 张静; 刘俊俊

    2012-01-01

    目的:分析石油作业女性外周血淋巴细胞姐妹染色单体互换( SCE)对习惯性流产的影响.方法:随机选择习惯性流产的石油作业女性26人为观察组和正常的育龄女性18人为对照组,检测其外周血淋巴细胞姐妹染色单体互换,记势SCE发生率.结果:观察组的外周血淋巴细胞SCE发生率为8.66 ±0.61明显高于对照组,差异有统计学意义(P<0.05).结论:SCE的发生可作为石油作业习惯性流产女性染色体结构稳定性的检测指标.石油作业环境中的某些有害物质对女性DNA损伤有一定的影响.%Objective; To analyze the effect of sister chromatid exchange (SCE) in lymphocytes in peripheral blood of the women in the petroleum operations on habitual abortion. Methods: Twenty - six women in the petroleum operations with habitual abortion and 18 normal women at childbearing age were selected randomly as observation group and control group respectively. SCE in lymphocytes in peripheral blood was detected, and the incidence was recorded. Results; The incidence of SCE in lymphocytes in peripheral blood of observation group was (8. 66 ±0. 61), which was significantly higher than that in control group (P <0. 05) . Conclusion; The occurrence of SCE can be used as a index to detect the structural stability of chromosomes in women with habitual abortion; some harmful substances in the environment in petroleum operations have a certain impact on injury of female DNA.

  14. "Pearl Sister"

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    HE Xiuying is the general manager of the Beihai Pearl Company in a small city by the Gulf of Beibu in Guangxi Zhuang Autonomous Region. Local people like to call her "Pearl Sister," because they have seen with their own eyes how He Xiuying has been transformed from an ordinary fisherwoman into a pearl expert and entrepreneur as pearl production has developed in Beihai. Born into a poor family, He Xiuying had to help her parents support her

  15. The template choice decision in meiosis: is the sister important?

    Science.gov (United States)

    Pradillo, Mónica; Santos, Juan L

    2011-10-01

    Recombination between homologous chromosomes is crucial to ensure their proper segregation during meiosis. This is achieved by regulating the choice of recombination template. In mitotic cells, double-strand break repair with the sister chromatid appears to be preferred, whereas interhomolog recombination is favoured during meiosis. However, in the last year, several studies in yeast have shown the importance of the meiotic recombination between sister chromatids. Although this thinking seems to be new, evidences for sister chromatid exchange during meiosis were obtained more than 50 years ago in non-model organisms. In this mini-review, we comment briefly on the most recent advances in this hot topic and also describe observations which suggest the existence of inter-sister repair during meiotic recombination. For instance, the behaviour of mammalian XY bivalents and that of trivalents in heterozygotes for chromosomal rearrangements are cited as examples. The "rediscovering" of the requirement for the sister template, although it seems to occur at a low frequency, will probably prompt further investigations in organisms other than yeast to understand the complexity of the partner choice during meiosis.

  16. Repairability during G1 of the inductor leisure of exchanges in the sister chromatid induced by alkylating agents in DNA substituted and no substituted with BUDR, in cells of the salivary gland of mouse In vivo; Reparabilidad durante G1 de las lesiones inductoras de intercambios en las cromatidas hermanas inducidos por agentes alquilantes en ADN sustituido y no sustituido con BrdU, en celulas de la glandula salival de raton In vivo

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez B, F

    2004-07-01

    In this work you determines the repair of the lesions inductoras of Sister chromatid exchange (ICHs) generated in the cells of the salivary gland of mouse, for the treatment with the N-Methyl-N-Nitrosourea (MNU), the N-Ethyl-N-Nitrosourea (ENU), the Methyl methanesulfonate (MMS) and the Ethyl methanesulfonate (EMS) in early and slow G1 of the first one and the second cellular division, that is to say before and after the cells incorporate 5-bromine-2 -Desoxyuridine (BrdU) in the DNA. Groups witness non treaties were included with mutagen. The cells of the salivary gland repaired the generated lesions partially by the MNU, the MMS and the EMS in the 1st division, and only the lesions induced by the ENU and MMS were repaired partially in the 2nd division. The ENU generates injure that they were not repaired in the 1st division and those taken place by the EMS were little repaired in the 2nd division. The methylating agents generated but ICHs that the ethylating. One observes that the BrdU makes to the molecule of the DNA but susceptible to the damage generated by the alkylating agents that induce the formation of the ICHs. This susceptibility was incremented around 150% for the treatment with the MNU, the ENU and the MMS, on the other hand for the EMS it was 3 times minor. It is proposed that the one electronegative atom of this analog of the timine would to work as a nucleophyllic center with which the electrophyllic compounds react. (Author)

  17. Phospho-H1 Decorates the Inter-chromatid Axis and Is Evicted along with Shugoshin by SET during Mitosis.

    Science.gov (United States)

    Krishnan, Swathi; Smits, Arne H; Vermeulen, Michiel; Reinberg, Danny

    2017-08-17

    Precise control of sister chromatid separation during mitosis is pivotal to maintaining genomic integrity. Yet, the regulatory mechanisms involved are not well understood. Remarkably, we discovered that linker histone H1 phosphorylated at S/T18 decorated the inter-chromatid axial DNA on mitotic chromosomes. Sister chromatid resolution during mitosis required the eviction of such H1S/T18ph by the chaperone SET, with this process being independent of and most likely downstream of arm-cohesin dissociation. SET also directed the disassembly of Shugoshins in a polo-like kinase 1-augmented manner, aiding centromere resolution. SET ablation compromised mitotic fidelity as evidenced by unresolved sister chromatids with marked accumulation of H1S/T18ph and centromeric Shugoshin. Thus, chaperone-assisted eviction of linker histones and Shugoshins is a fundamental step in mammalian mitotic progression. Our findings also elucidate the functional implications of the decades-old observation of mitotic linker histone phosphorylation, serving as a paradigm to explore the role of linker histones in bio-signaling processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Sisters in Dutch hospitals.

    Science.gov (United States)

    van den Bergh-Braam, A H

    1985-11-01

    This study focuses on hospital sisters in 30 Dutch hospitals. The so-called role-set approach has been adopted. In this approach the sisters are the focal persons. Direct superiors, specialists, registered nurses and student nurses acted as role-senders. The possible number of respondents is 600 (120 of each group). The response of hospital sisters is 100%, that of role-senders 88%. The study started out as an attempt to collect background information on the causes of wastage of sisters. High wastage rates are generally regarded as an indication of an unfavourable working environment. Since hospital sisters occupy a key position in hospitals, the ward problems will be studied from their angle. Although wastage rates have dropped recently, it does not necessarily follow that the working environment has improved. Wastage is known to act as a safety valve, thus allowing tensions to resolve. The threat of unemployment clogs this outlet, which increases the tensions on the hospital ward. Data from the study show that work overload is one of the major stress factors for sisters. Analyses demonstrated that there exists a relationship between work overload and tensions with the management and direct superiors, tensions in job execution, irritableness on the ward, low self-esteem, health complaints and psychological condition. Sisters with an excessive job involvement refer to work overload more often than their moderate colleagues. There is a relationship between an unfavourable working environment and irritableness of sisters.

  19. The Lehman Sisters Hypothesis

    NARCIS (Netherlands)

    I.P. van Staveren (Irene)

    2014-01-01

    markdownabstract__Abstract__ This article explores the Lehman Sisters Hypothesis. It reviews empirical literature about gender differences in behavioral, experimental, and neuro-economics as well as in other fields of behavioral research. It discusses gender differences along three dimensions of fi

  20. Analysis of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    孙淑珍

    2004-01-01

    Chapter Ⅰ Introduction  Sitting in the rocking chair,Carrie dreams her future.This is the deep impression the novel"Sister Carrie"gives us,which is written by Theodore Dreiser(1871-1945),the great American realism writer.  ……

  1. Sister Carrie in China

    Institute of Scientific and Technical Information of China (English)

    殷希

    2015-01-01

    Sister Carrie has received many Chinese scholar's attention, and it has quantity relevance researches. Therefore, it is valuable to study why it is popular in China and it's education meaning for Chinese people. In addition, to analysis the domestic re-searches and find it's exist problems can help us make a new breakthrough from the study.

  2. Separase Is Required for Homolog and Sister Disjunction during Drosophila melanogaster Male Meiosis, but Not for Biorientation of Sister Centromeres.

    Science.gov (United States)

    Blattner, Ariane C; Chaurasia, Soumya; McKee, Bruce D; Lehner, Christian F

    2016-04-01

    Spatially controlled release of sister chromatid cohesion during progression through the meiotic divisions is of paramount importance for error-free chromosome segregation during meiosis. Cohesion is mediated by the cohesin protein complex and cleavage of one of its subunits by the endoprotease separase removes cohesin first from chromosome arms during exit from meiosis I and later from the pericentromeric region during exit from meiosis II. At the onset of the meiotic divisions, cohesin has also been proposed to be present within the centromeric region for the unification of sister centromeres into a single functional entity, allowing bipolar orientation of paired homologs within the meiosis I spindle. Separase-mediated removal of centromeric cohesin during exit from meiosis I might explain sister centromere individualization which is essential for subsequent biorientation of sister centromeres during meiosis II. To characterize a potential involvement of separase in sister centromere individualization before meiosis II, we have studied meiosis in Drosophila melanogaster males where homologs are not paired in the canonical manner. Meiosis does not include meiotic recombination and synaptonemal complex formation in these males. Instead, an alternative homolog conjunction system keeps homologous chromosomes in pairs. Using independent strategies for spermatocyte-specific depletion of separase complex subunits in combination with time-lapse imaging, we demonstrate that separase is required for the inactivation of this alternative conjunction at anaphase I onset. Mutations that abolish alternative homolog conjunction therefore result in random segregation of univalents during meiosis I also after separase depletion. Interestingly, these univalents become bioriented during meiosis II, suggesting that sister centromere individualization before meiosis II does not require separase.

  3. Separase Is Required for Homolog and Sister Disjunction during Drosophila melanogaster Male Meiosis, but Not for Biorientation of Sister Centromeres.

    Directory of Open Access Journals (Sweden)

    Ariane C Blattner

    2016-04-01

    Full Text Available Spatially controlled release of sister chromatid cohesion during progression through the meiotic divisions is of paramount importance for error-free chromosome segregation during meiosis. Cohesion is mediated by the cohesin protein complex and cleavage of one of its subunits by the endoprotease separase removes cohesin first from chromosome arms during exit from meiosis I and later from the pericentromeric region during exit from meiosis II. At the onset of the meiotic divisions, cohesin has also been proposed to be present within the centromeric region for the unification of sister centromeres into a single functional entity, allowing bipolar orientation of paired homologs within the meiosis I spindle. Separase-mediated removal of centromeric cohesin during exit from meiosis I might explain sister centromere individualization which is essential for subsequent biorientation of sister centromeres during meiosis II. To characterize a potential involvement of separase in sister centromere individualization before meiosis II, we have studied meiosis in Drosophila melanogaster males where homologs are not paired in the canonical manner. Meiosis does not include meiotic recombination and synaptonemal complex formation in these males. Instead, an alternative homolog conjunction system keeps homologous chromosomes in pairs. Using independent strategies for spermatocyte-specific depletion of separase complex subunits in combination with time-lapse imaging, we demonstrate that separase is required for the inactivation of this alternative conjunction at anaphase I onset. Mutations that abolish alternative homolog conjunction therefore result in random segregation of univalents during meiosis I also after separase depletion. Interestingly, these univalents become bioriented during meiosis II, suggesting that sister centromere individualization before meiosis II does not require separase.

  4. The Elg1 Clamp Loader Plays a Role in Sister Chromatid Cohesion

    OpenAIRE

    Oren Parnas; Adi Zipin-Roitman; Yuval Mazor; Batia Liefshitz; Shay Ben-Aroya; Martin Kupiec

    2009-01-01

    Mutations in the ELG1 gene of yeast lead to genomic instability, manifested in high levels of genetic recombination, chromosome loss, and gross chromosomal rearrangements. Elg1 shows similarity to the large subunit of the Replication Factor C clamp loader, and forms a RFC-like (RLC) complex in conjunction with the 4 small RFC subunits. Two additional RLCs exist in yeast: in one of them the large subunit is Ctf18, and in the other, Rad24. Ctf18 has been characterized as the RLC that functions ...

  5. Bloom Helicase and DNA Topoisomerase IIIα Are Involved in the Dissolution of Sister Chromatids

    OpenAIRE

    Seki, Masayuki; Nakagawa, Takayuki; Seki, Takahiko; Kato, Genta; Tada, Shusuke; TAKAHASHI, Yuriko; Yoshimura, Akari; Kobayashi, Takayuki; Aoki, Ayako; Otsuki, Makoto; Felix A Habermann; Tanabe, Hideyuki; Ishii, Yutaka; Enomoto, Takemi

    2006-01-01

    Bloom's syndrome (BS) is an autosomal disorder characterized by predisposition to a wide variety of cancers. The gene product whose mutation leads to BS is the RecQ family helicase BLM, which forms a complex with DNA topoisomerase IIIα (Top3α). However, the physiological relevance of the interaction between BLM and Top3α within the cell remains unclear. We show here that Top3α depletion causes accumulation of cells in G2 phase, enlargement of nuclei, and chromosome gaps and breaks that occur ...

  6. Mouse RAD54 affects DNA double-strand break repair and sister chromatid exchange

    NARCIS (Netherlands)

    H.B. Beverloo (Berna); R.D. Johnson (Roger); M. Jasin (Maria); R. Kanaar (Roland); J.H.J. Hoeijmakers (Jan); M.L.G. Dronkert (Mies)

    2000-01-01

    textabstractCells can achieve error-free repair of DNA double-strand breaks (DSBs) by homologous recombination through gene conversion with or without crossover. In contrast, an alternative homology-dependent DSB repair pathway, single-strand annealing (SSA), results in deletions. In this study, we

  7. DNA-PK-dependent RPA2 hyperphosphorylation facilitates DNA repair and suppresses sister chromatid exchange.

    Directory of Open Access Journals (Sweden)

    Hungjiun Liaw

    Full Text Available Hyperphosphorylation of RPA2 at serine 4 and serine 8 (S4, S8 has been used as a marker for activation of the DNA damage response. What types of DNA lesions cause RPA2 hyperphosphorylation, which kinase(s are responsible for them, and what is the biological outcome of these phosphorylations, however, have not been fully investigated. In this study we demonstrate that RPA2 hyperphosphorylation occurs primarily in response to genotoxic stresses that cause high levels of DNA double-strand breaks (DSBs and that the DNA-dependent protein kinase complex (DNA-PK is responsible for the modifications in vivo. Alteration of S4, S8 of RPA2 to alanines, which prevent phosphorylations at these sites, caused increased mitotic entry with concomitant increases in RAD51 foci and homologous recombination. Taken together, our results demonstrate that RPA2 hyperphosphorylation by DNA-PK in response to DSBs blocks unscheduled homologous recombination and delays mitotic entry. This pathway thus permits cells to repair DNA damage properly and increase cell viability.

  8. 40 CFR 79.65 - In vivo sister chromatid exchange assay.

    Science.gov (United States)

    2010-07-01

    ... least five female and five male animals per experimental and control group shall be used. The use of a... PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Testing Requirements for Registration § 79.65... days to three or more concentrations of a test substance in air. Groups of animals are sacrificed at...

  9. Linking Sister Chromatid Cohesion to Apoptosis and Aneuploidy in the Development of Breast Cancer

    Science.gov (United States)

    2005-07-01

    instead ofa pituitary isograft as in the original specific optical filters TRI, TR2, and TR3 (Chroma Technology, Brattleboro, experiment. A pituitary... isograft results in marked increases in the circulating VT). Quantitative evaluation of the hybridization was performed using a levels of prolactin and...transcription start sites Untreated 9/50(18) 49.2 16 6/10 Pituitary isograft 7/50(14) 41.4 14 7/7using Genomatix Suite and a neural network promoter prediction

  10. Review of the international symposium, sister chromatid exchanges: twenty-five years of experimental research

    Energy Technology Data Exchange (ETDEWEB)

    Tice, R.R.; Lambert, B.; Morimoto, Kanehisa; Hollaender, A.

    1983-01-01

    The purpose of this symposium was to honor initial research at Brookhaven by bringing internationally recognized leaders in the fields of genetics, cytogenetics, carcinogenesis, mutagenesis, radiation biology, toxicology, and environmental health together into an open forum to present and discuss: (1) current knowledge of the induction and formation of SCEs and their relationship to other biological endpoints, including carcinogenesis, mutagenesis, transformation, clastogenesis, DNA damage and repair, and cellular toxicity; (2) the optimal strategies for the utilization of SCEs in genetic toxicology testing schemes involving in vitro and in vivo exposure situations; (3) the most valid statistical methods for analyzing SCE data obtained from cells in culture, from cells in intact organisms, and from cells in humans; (4) the relevance of SCEs as an indicator of human disease states, both inherited and acquired, and of progress in disease treatment; and (5) the use of SCEs as an indicator of human exposure to genotoxic agents and their relevance as a prognosticator of future adverse health outcomes. This report summarizes the presentations. 7 references. (ACR)

  11. Fanconi anaemia proteins are associated with sister chromatid bridging in mitosis

    DEFF Research Database (Denmark)

    Ying, Songmin; Hickson, Ian D

    2011-01-01

    that specifically occur during chromosome segregation in mitosis. The BS protein, BLM, was shown recently to define a novel class of anaphase DNA bridge structures that, in some cases, also contain FA proteins. We will discuss the possible source of these bridges and the role that FA proteins and BLM might play...

  12. PICH promotes sister chromatid disjunction and co-operates with topoisomerase II in mitosis

    DEFF Research Database (Denmark)

    Nielsen, Christian Thomas Friberg; Huttner, Diana; Bizard, Anna H

    2015-01-01

    PICH is a SNF2 family DNA translocase that binds to ultra-fine DNA bridges (UFBs) in mitosis. Numerous roles for PICH have been proposed from protein depletion experiments, but a consensus has failed to emerge. Here, we report that deletion of PICH in avian cells causes chromosome structural......-193-treated cells. We propose that PICH and Topo II cooperate to prevent chromosome missegregation events in mitosis....

  13. Homologous recombination, sister chromatid cohesion, and chromosome condensation in mammalian meiosis

    NARCIS (Netherlands)

    Eijpe, M.

    2002-01-01

    In the life cycle of sexually reproducing eukaryotes, haploid and diploid generations of cells alternate. Two types of cell division occur in such a life cycle: mitosis and meiosis. They are compared in chapter 1 . Haploid and diploid cells can multiply by mitoses.

  14. The origin recognition complex links replication, sister chromatid cohesion and transcriptional silencing in Saccharomyces cerevisiae

    NARCIS (Netherlands)

    Suter, Bernhard; Tong, Amy; Chang, Michael; Yu, Lisa; Brown, Grant W; Boone, Charles; Rine, Jasper

    2004-01-01

    Mutations in genes encoding the origin recognition complex (ORC) of Saccharomyces cerevisiae affect initiation of DNA replication and transcriptional repression at the silent mating-type loci. To explore the function of ORC in more detail, a screen for genetic interactions was undertaken using large

  15. Chromatids segregate without centrosomes during Caenorhabditis elegans mitosis in a Ran- and CLASP-dependent manner.

    Science.gov (United States)

    Nahaboo, Wallis; Zouak, Melissa; Askjaer, Peter; Delattre, Marie

    2015-06-01

    During mitosis, chromosomes are connected to a microtubule-based spindle. Current models propose that displacement of the spindle poles and/or the activity of kinetochore microtubules generate mechanical forces that segregate sister chromatids. Using laser destruction of the centrosomes during Caenorhabditis elegans mitosis, we show that neither of these mechanisms is necessary to achieve proper chromatid segregation. Our results strongly suggest that an outward force generated by the spindle midzone, independently of centrosomes, is sufficient to segregate chromosomes in mitotic cells. Using mutant and RNAi analysis, we show that the microtubule-bundling protein SPD-1/MAP-65 and BMK-1/kinesin-5 act as a brake opposing the force generated by the spindle midzone. Conversely, we identify a novel role for two microtubule-growth and nucleation agents, Ran and CLASP, in the establishment of the centrosome-independent force during anaphase. Their involvement raises the interesting possibility that microtubule polymerization of midzone microtubules is continuously required to sustain chromosome segregation during mitosis.

  16. Left-right symmetry breaking in mice by left-right dynein may occur via a biased chromatid segregation mechanism, without directly involving the Nodal gene

    Directory of Open Access Journals (Sweden)

    Stephan eSauer

    2012-11-01

    Full Text Available Ever since cloning the classic iv mutation identified the ‘left-right dynein’ (lrd gene in mice, most research on body laterality determination has focused on its function in motile cilia at the node embryonic organizer. This model is attractive, as it links chirality of cilia architecture to asymmetry development. However, lrd is also expressed in blastocysts and embryonic stem cells, where it was shown to bias the segregation of recombined sister chromatids away from each other in mitosis. These data suggested that lrd is part of a cellular mechanism that recognizes and selectively segregates sister chromatids based on their replication history: old ‘Watson’ vs. old ‘Crick’ strands. We previously proposed that the mouse left-right axis is established via an asymmetric cell division prior to/or during gastrulation. In this model, left-right dynein selectively segregates epigenetically differentiated sister chromatids harboring a hypothetical ‘left-right axis development 1’ (‘lra1’ gene during the left-right axis establishing cell division. Here, asymmetry development would be ultimately governed by the chirality of the cytoskeleton and the DNA molecule. Our model predicts that randomization of chromatid segregation in lrd mutants should produce embryos with 25% situs solitus, 25% situs inversus, and 50% embryonic death due to heterotaxia and isomerism. Here we confirmed this prediction by using two distinct lrd mutant alleles. Other than lrd, thus far Nodal gene is the most upstream function implicated in visceral organs laterality determination. We next tested whether the Nodal gene constitutes the lra1 gene hypothesized in the model by testing mutant’s effect on 50% embryonic lethality observed in lrd mutants. Since Nodal mutation did not suppress lethality, we conclude that Nodal is not equivalent to the lra1 gene. In summary, we describe the origin of 50% lethality in lrd mutant mice not yet explained by any other

  17. Sisters Hope - the exposed self

    DEFF Research Database (Denmark)

    Lawaetz, Anna; Hallberg, Gry Worre

    Sisters Hope is an art-educational method and a practice-led research tool, rooted in the construction of a fictional parallel universe revolving around the twin sisters Coco and Coca Pebber. Our work is rooted in the ambition to democratize the aesthetic dimension through ‘affective engineering......’ and the establishment of fictional spaces outside the institutional art context. In the Unfolding Academia-context Sisters Hope investigates new forms of research and (re)presentation through the creation of interactive and affective learning-spaces. At Collective Futures Sisters Hope explored questions such as: How...

  18. Sister-sister incest: data from an anonymous computerized survey.

    Science.gov (United States)

    Stroebel, Sandra S; O'Keefe, Stephen L; Griffee, Karen; Kuo, Shih-Ya; Beard, Keith W; Kommor, Martin J

    2013-01-01

    Retrospective data were entered anonymously by 1,521 adult women using a computer-assisted self-interview. Thirty-one participants were victims of sister-sister incest, 40 were victims of brother-sister incest, 19 were victims of father-daughter incest, 8 were victims of sexual abuse by an adult female (including one mother), and 232 were victims of sexual abuse by an adult male other than their father before reaching 18 years of age. The rest (1,203) served as controls. The victims of sister-sister incest had significantly more problematic outcomes than controls on many measures as adults. Victims of sister-sister incest were more depressed and more likely than controls to be distant from the perpetrator-sister and to have traded sex for money, experienced an unplanned pregnancy, engaged in four different types of masturbation, and engaged in 13 different same-sex behaviors. Our findings were consistent with other reports of early eroticization and persistent hypereroticization of incest victims.

  19. Sisters unbound is required for meiotic centromeric cohesion in Drosophila melanogaster.

    Science.gov (United States)

    Krishnan, Badri; Thomas, Sharon E; Yan, Rihui; Yamada, Hirotsugu; Zhulin, Igor B; McKee, Bruce D

    2014-11-01

    Regular meiotic chromosome segregation requires sister centromeres to mono-orient (orient to the same pole) during the first meiotic division (meiosis I) when homologous chromosomes segregate, and to bi-orient (orient to opposite poles) during the second meiotic division (meiosis II) when sister chromatids segregate. Both orientation patterns require cohesion between sister centromeres, which is established during meiotic DNA replication and persists until anaphase of meiosis II. Meiotic cohesion is mediated by a conserved four-protein complex called cohesin that includes two structural maintenance of chromosomes (SMC) subunits (SMC1 and SMC3) and two non-SMC subunits. In Drosophila melanogaster, however, the meiotic cohesion apparatus has not been fully characterized and the non-SMC subunits have not been identified. We have identified a novel Drosophila gene called sisters unbound (sunn), which is required for stable sister chromatid cohesion throughout meiosis. sunn mutations disrupt centromere cohesion during prophase I and cause high frequencies of non-disjunction (NDJ) at both meiotic divisions in both sexes. SUNN co-localizes at centromeres with the cohesion proteins SMC1 and SOLO in both sexes and is necessary for the recruitment of both proteins to centromeres. Although SUNN lacks sequence homology to cohesins, bioinformatic analysis indicates that SUNN may be a structural homolog of the non-SMC cohesin subunit stromalin (SA), suggesting that SUNN may serve as a meiosis-specific cohesin subunit. In conclusion, our data show that SUNN is an essential meiosis-specific Drosophila cohesion protein. Copyright © 2014 by the Genetics Society of America.

  20. Enhanced G2 chromatid radiosensitivity in dyskeratosis congenita fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    DeBauche, D.M.; Pai, G.S.; Stanley, W.S. (Medical Univ. of South Carolina, Charleston (USA))

    1990-02-01

    Dyskeratosis congenita (DC) is an inherited disorder characterized by reticular pigmentation of the skin, dystrophic nails, mucosal leukoplakia, and a predisposition to cancer in early adult life. In the majority of cases, DC is an X-linked recessive trait. However, one or more autosomal form(s) of DC may exist. Although excessive spontaneous chromatid breakage has been reported in DC, it is not a consistent cytological marker for this disorder. We examined the frequency and specificity of X-irradiation-induced G2 chromatid breakage in fibroblasts from three unrelated DC patients (two males and one female). Metaphase cells from DC patients had significantly more chromatid breaks (16-18-fold and 17-26-fold at 50 and 100 rad X-irradiation, respectively) and chromatid gaps (10-12-fold and 6-7-fold at 50 and 100 rad, respectively) than those from two different controls. Analysis of banded chromosomes revealed a nonrandom distribution of chromatid aberrations in DC but not in controls, a distribution corresponding to some of the known breakpoints for cancer-specific rearrangements, constitutive fragile sites, and/or loci for cellular proto-oncogenes. The significance of this finding for cancer predisposition in DC patients is uncertain, but the increased susceptibility of X-irradiation-induced chromatid breakage may serve as a cellular marker of diagnostic value.

  1. Where are Sedna's Sisters?

    Science.gov (United States)

    Bartlett, D. F.

    2005-05-01

    Simulations of the formation of the Oort cloud from the Kuiper Belt typically are presented as an animated scatter diagram. Here the orbit of each object appears as a point of perihelion distance q and semi-major axis a. (eg. Levison, Morbidelli, & Dones 2004). These plots show a conspicuous void, bounded by the inequalities: q 50 AU, and a Bermuda Triangle". The only present occupant is Sedna (q=76 AU, a=501 AU). Brown, Trujillo, & Rabinowitz , the discovers of Sedna, have challenged others to explain how Sedna got inside the triangle and to predict where similar objects might be found. Sedna could not have simply formed in its current orbit by the accumulation of smaller objects (Stern 2005). Several authors have suggested that a passing star scattered Sedna into the triangle shortly after the birth of the solar system. Here I offer an alternative which uses the very strong galactic tidal forces of the Sinusoidal potential (Bartlett 2001, 2004). In this potential, the numerator of Newton's law is replaced by GM cos(ko r) where ko = 2 π / lambdao and the 'wavelength' λ o is 425 pc. The 20 radial oscillations between the sun and the center of the Galaxy give tidal forces that are 120 times as big as generally expected. I will show how this tidal force, acting over the lifetime of the solar system, could move the perihelion of Sedna from about 40 to 76 AU. Sedna's sisters are likely to have still larger q & a and to have perihelia in two specific quadrants of the ecliptic plane.

  2. Overexpression of SETβ, a protein localizing to centromeres, causes precocious separation of chromatids during the first meiosis of mouse oocytes.

    Science.gov (United States)

    Qi, Shu-Tao; Wang, Zhen-Bo; Ouyang, Ying-Chun; Zhang, Qing-Hua; Hu, Meng-Wen; Huang, Xin; Ge, Zhaojia; Guo, Lei; Wang, Ya-Peng; Hou, Yi; Schatten, Heide; Sun, Qing-Yuan

    2013-04-01

    Chromosome segregation in mammalian oocyte meiosis is an error-prone process, and any mistake in this process may result in aneuploidy, which is the main cause of infertility, abortion and many genetic diseases. It is now well known that shugoshin and protein phosphatase 2A (PP2A) play important roles in the protection of centromeric cohesion during the first meiosis. PP2A can antagonize the phosphorylation of rec8, a member of the cohesin complex, at the centromeres and thus prevent cleavage of rec8 and so maintain the cohesion of chromatids. SETβ is a protein that physically interacts with shugoshin and inhibits PP2A activity. We thus hypothesized that SETβ might regulate cohesion protection and chromosome segregation during oocyte meiotic maturation. Here we report for the first time the expression, subcellular localization and functions of SETβ during mouse oocyte meiosis. Immunoblotting analysis showed that the expression level of SETβ was stable from the germinal vesicle stage to the MII stage of oocyte meiosis. Immunofluorescence analysis showed SETβ accumulation in the nucleus at the germinal vesicle stage, whereas it was targeted mainly to the inner centromere area and faintly localized to the interchromatid axes from germinal vesicle breakdown to MI stages. At the MII stage, SETβ still localized to the inner centromere area, but could relocalize to kinetochores in a process perhaps dependent on the tension on the centromeres. SETβ partly colocalized with PP2A at the inner centromere area. Overexpression of SETβ in mouse oocytes caused precocious separation of sister chromatids, but depletion of SETβ by RNAi showed little effects on the meiotic maturation process. Taken together, our results suggest that SETβ, even though it localizes to centromeres, might not be essential for chromosome separation during mouse oocyte meiotic maturation, although its forced overexpression causes premature chromatid separation.

  3. Naturalistic Elements in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    刘艳晖

    2007-01-01

    @@ Theodore Dreiser is considered to be a controversial writer.His first novel.Sister Carrie makes a new way of presenting re-ality.This paper discusses the naturalistic elements from the de-tailed description of the environment in that society.

  4. A Brief Analysis of Sister Carrie's Character

    Science.gov (United States)

    Yu, Hanying

    2010-01-01

    Carrie is always dreaming while the rocking chair is rocking again and again, this is the deep impression on us after we read "Sister Carrie" which is the first novel of Theodore Dreiser. In this novel the protagonist Sister Carrie is a controversial person. This paper tries to analyze the character of Sister Carrie in order to find out…

  5. Abnormal centromere-chromatid apposition (ACCA) and Peters' anomaly.

    Science.gov (United States)

    Wertelecki, W; Dev, V G; Superneau, D W

    1985-08-01

    Abnormal centromere-chromatid apposition (ACCA) was noted in a patient with Peters' anomaly. Previous reports of ACCA emphasized its association with tetraphocomelia and other congenital malformations (Roberts, SC Phocomelia, Pseudothalidomide Syndromes). This report expands the array of congenital malformations associated with ACCA and emphasizes the diagnostic importance of ocular defects for the ascertainment of additional cases of ACCA and its possible relationship with abnormal cell division.

  6. Differential subcellular localizations of two human Sgo1 isoforms: implications in regulation of sister chromatid cohesion and microtubule dynamics.

    Science.gov (United States)

    Wang, Xiaoxing; Yang, Yali; Dai, Wei

    2006-03-01

    Sgo1 is an evolutionarily conserved protein that functions as a protector of centromeric cohesin during mitosis. Recent studies show that Sgo1 is kinetochorelocalized and required for accurate segregation of mitotic chromosomes because depletion of Sgo1 in mammalian cells results in precocious initiation of anaphase and mis-segregation of chromosomes. Through analysis of GFP fusion proteins, we observe that two major isoforms of human Sgo1 exhibit entirely different subcellular localization patterns. The short isoform of Sgo1 (sSgo1) that lacks exon 6 does not localize to kinetochores during any stages of the cell cycle. Instead, it is enriched at mitotic spindles. On the other hand, the longer isoform of Sgo1 primarily localizes to kinetochores during G(2) phase and mitotic prophase, metaphase, and anaphase. During late mitosis, Sgo1 does not appear to be associated with kinetochores. Intriguingly, the longer isoform of Sgo1 forms discrete foci during S phase, some of which are apparently in the nucleoli. However, a majority of these foci colocalize with CREST, a kinetochore antigen, indicating that Sgo1 is loaded onto kinetochores during or immediately after DNA replication. Together, our studies suggest that different isoforms of Sgo1 may play distinct roles during the cell cycle and that Sgo1 may have an interphase function as well.

  7. Field Verification Program (Aquatic Disposal). Sister Chromatid Exchange in Marine Polychaetes Exposed to Black Rock Harbor Sediment.

    Science.gov (United States)

    1985-07-01

    improbable that relationships would be detected given the variability inherent in the data. With a sample size of seven, the correlation coefficient would have...strain TA2637) with metabolic activation (Tikkanen, Matsushima, and Natori 1983), possibly via the generation of active oxygen (Brown 1980; Chesis ...Exchange as an Indicator of Mutagenesis," Nature (London), Vol 2- , p 551-553. Chesi , P. I., Levin, D. E., Smith, M. T., Ernster, L., and Ames, B. N. 1984

  8. A study of sister chromatid exchange and somatic cell mutation in hospital workers exposed to ethylene oxide.

    OpenAIRE

    Tomkins, D J; T. Haines; Lawrence, M.; Rosa, N

    1993-01-01

    To investigate the risks of exposure to ethylene oxide (EO) at current permissible levels and at past higher levels, an inception cohort of sterilizer operators and supervisors from the Central Processing Department (CPD), respiratory therapists, and engineers exposed to EO were identified at the McMaster University Medical Centre. A comparison group from Nutrition Services (NUTR) were matched with the CPD workers on the basis of sex, age, and smoking habit. The present report is based on gen...

  9. A study of sister chromatid exchange and somatic cell mutation in hospital workers exposed to ethylene oxide.

    Science.gov (United States)

    Tomkins, D J; Haines, T; Lawrence, M; Rosa, N

    1993-10-01

    To investigate the risks of exposure to ethylene oxide (EO) at current permissible levels and at past higher levels, an inception cohort of sterilizer operators and supervisors from the Central Processing Department (CPD), respiratory therapists, and engineers exposed to EO were identified at the McMaster University Medical Centre. A comparison group from Nutrition Services (NUTR) were matched with the CPD workers on the basis of sex, age, and smoking habit. The present report is based on genetic test results for the 94 CPD and matched NUTR workers only. Statistical analysis based on the mean SCE frequency in the top 5, top 10, and all cells (50 cells scored per individual) and high frequency cells (HFC) based on the 95th percentile for nonsmoking control subjects showed a direct association with current smoking but not with EO exposure. Similarly, statistical analysis of the somatic cell mutation (SCMT) variant frequencies did not demonstrate an association with EO exposure, nor with smoking. Regression analysis indicated that sex was the only other covariate that significantly affected SCE. Age was weakly associated with SCMT. A statistically significant interaction between occupational exposure and smoking habits was observed only for the mean SCE frequency of the top 5 and top 10 cells when the 11 current CPD/NUTR pairs were not included. Thus, this interaction should be interpreted with caution.

  10. Discovering non-random segregation of sister chromatids: The naïve treatment of a premature discovery

    Directory of Open Access Journals (Sweden)

    Karl G. Lark

    2013-02-01

    Full Text Available The discovery of non-random chromosome segregation is discussed from the perspective of what was known in1965 and1966. The distinction between daughter, parent or grandparent strands of DNA was developed in a bacterial system and led to the discovery that multiple copies of DNA elements of bacteria are not distributed randomly with respect to the age of the template strand. Experiments with higher eukaryotic cells demonstrated that during mitosis Mendel’s laws were violated; and the initial serendipitous choice of eukaryotic cell system led to the striking example of non-random segregation of parent and grand-parent DNA template strands in primary cultures of cells derived from mouse embryos. Attempts to extrapolate these findings to established TC lines demonstrated that the property could be lost. Experiments using plant root tips demonstrated that the phenomenon exists in plants and that it was, at some level, under genetic control. Despite publication in major journals and symposia (Lark et al. (1966a; Lark (1967a; 1967b; 1969, 1969a; 1969b the potential implications of these findings were ignored for several decades. Here we explore possible reasons for the pre-maturity (Stent, 1972 of this discovery.

  11. Parallel increases in sister chromatid exchanges at base level and with UV treatment in human opiate users

    Energy Technology Data Exchange (ETDEWEB)

    Shafer, D.A.; Falek, A.; Madden, J.J.; Tadayon, F.; Pline, M. (Georgia Mental Health Inst., Atlanta (USA). Human Genetics Research Lab.; Emory Univ., Atlanta, GA (USA). Dept. of Psychiatry); Bokos, P.J. (Interventions, Chicago, IL (USA)); Kuehnle, J.C.; Mendelson, J. (McLean Hospital, Belmont, MA (USA). Alcohol and Drug Abuse Research Center)

    1983-04-01

    The SCE base level frequency and SCE levels induced by far-UV (254 nm) treatment of cells in early G/sub 1/ and early S phases of the cell cycle were significantly higher in leukocytes from heroin addicts as compared to controls. The increased SCE levels in addicts was greatest at base level and smallest after UV irradiation of cells in S phase. These results corrobate and extend our previous findings of increased chromosome damage and reduced DNA-repair synthesis in heroin users. Since opiates do not directly damage DNA, the elevated cytogenetic effects associated with opiate use probably arise from secondary promotional effects related to opiate-mediated alterations in leukocyte metabolism.

  12. Onderzoek naar de inductie van chromosoomafwijkingen en "sister- chromatid exchanges" door acrylamide met Chinese hamster cellen in vitro

    NARCIS (Netherlands)

    Knaap; A.G.A.C.; Bergkamp; W.G.M.; Groot; M.G.

    1986-01-01

    Acrylamide bleek een clastogene werking te hebben in een test op chromosoomafwijkingen met Chinese hamster cellen in vitro vanaf 0,1 mg/ml (1,4 mmol/l), zowel in aan- als afwezigheid van een systeem voor metaboliosche activering (S9). Tevens induceerde acrylamide in deze cellen een significante

  13. 78 FR 45061 - Safety Zone; Sister Bay Marina Fest Fireworks and Ski Show, Sister Bay, WI

    Science.gov (United States)

    2013-07-26

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Sister Bay Marina Fest Fireworks and Ski... intended to restrict vessels from a portion of Sister Bay due to a fireworks display and ski show. This... with the fireworks display and ski show in Sister Bay on August 31, 2013. DATES: This rule is...

  14. A FEMINIST READING OF SISTER CARRIE

    Institute of Scientific and Technical Information of China (English)

    高陈科

    2011-01-01

    In the history of American literature, Sister Carrie has always been a controversial character. The critics regard Carrie either as a "fallen woman" or as a "new women". This thesis aims to offer a feminist reading of the image of Sister Carrie in the con

  15. Unique geometry of sister kinetochores in human oocytes during meiosis I may explain maternal age-associated increases in chromosomal abnormalities.

    Science.gov (United States)

    Patel, Jessica; Tan, Seang Lin; Hartshorne, Geraldine M; McAinsh, Andrew D

    2015-12-30

    The first meiotic division in human oocytes is highly error-prone and contributes to the uniquely high incidence of aneuploidy observed in human pregnancies. A successful meiosis I (MI) division entails separation of homologous chromosome pairs and co-segregation of sister chromatids. For this to happen, sister kinetochores must form attachments to spindle kinetochore-fibres emanating from the same pole. In mouse and budding yeast, sister kinetochores remain closely associated with each other during MI, enabling them to act as a single unified structure. However, whether this arrangement also applies in human meiosis I oocytes was unclear. In this study, we perform high-resolution imaging of over 1900 kinetochores in human oocytes, to examine the geometry and architecture of the human meiotic kinetochore. We reveal that sister kinetochores in MI are not physically fused, and instead individual kinetochores within a pair are capable of forming independent attachments to spindle k-fibres. Notably, with increasing female age, the separation between kinetochores increases, suggesting a degradation of centromeric cohesion and/or changes in kinetochore architecture. Our data suggest that the differential arrangement of sister kinetochores and dual k-fibre attachments may explain the high proportion of unstable attachments that form in MI and thus indicate why human oocytes are prone to aneuploidy, particularly with increasing maternal age.

  16. Unique geometry of sister kinetochores in human oocytes during meiosis I may explain maternal age-associated increases in chromosomal abnormalities

    Directory of Open Access Journals (Sweden)

    Jessica Patel

    2016-02-01

    Full Text Available The first meiotic division in human oocytes is highly error-prone and contributes to the uniquely high incidence of aneuploidy observed in human pregnancies. A successful meiosis I (MI division entails separation of homologous chromosome pairs and co-segregation of sister chromatids. For this to happen, sister kinetochores must form attachments to spindle kinetochore-fibres emanating from the same pole. In mouse and budding yeast, sister kinetochores remain closely associated with each other during MI, enabling them to act as a single unified structure. However, whether this arrangement also applies in human meiosis I oocytes was unclear. In this study, we perform high-resolution imaging of over 1900 kinetochores in human oocytes, to examine the geometry and architecture of the human meiotic kinetochore. We reveal that sister kinetochores in MI are not physically fused, and instead individual kinetochores within a pair are capable of forming independent attachments to spindle k-fibres. Notably, with increasing female age, the separation between kinetochores increases, suggesting a degradation of centromeric cohesion and/or changes in kinetochore architecture. Our data suggest that the differential arrangement of sister kinetochores and dual k-fibre attachments may explain the high proportion of unstable attachments that form in MI and thus indicate why human oocytes are prone to aneuploidy, particularly with increasing maternal age.

  17. All in the Family: The Sister Study

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues All in the Family: The Sister Study Past Issues / ... that may ultimately eliminate this dreaded disease. We all know that breast cancer does not discriminate. Whether ...

  18. A Naturalistic Reading of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    谈月

    2016-01-01

    Sister Carrie is well known as the works in which naturalism attained maturity in America. Up until now, the relevant research on Dreiser and his Sister Carrie abroad and at home is primarily concerned with the frustration of American dream, the naturalistic thoughts and pessimism. The paper attempts to study it from naturalistic point of view and explain how environmental, hereditary factors and the idea of“survival of the fittest”influence Carrie’s fate.

  19. [Two Dutch sisters in analysis with Freud].

    Science.gov (United States)

    Stroeken, Harry

    2010-01-01

    The author provides persuasive or at least plausible data for the identity of two patients recorded by Freud in his working season of 1910/11. They were two sisters, living in The Hague/Leiden, who came from a rich banker's family, the van der Lindens. Whereas the treatment does not seem to have led to any decisive improvement for the older of the two, it may have encouraged the younger sister to seek divorce.

  20. Sisters Hope - Protected by the Fiction

    DEFF Research Database (Denmark)

    Lawaetz, Anna; Hallberg, Gry Worre

    2011-01-01

    In this article we will introduce the fictional and art-pedagogical universe of Sisters Hope and describe how it in different ways transcends into contexts beyond the art world and thus functions as a tool to democratize the aesthetic dimension and mode of being within high schools, academia...

  1. Comments on the image of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    张楠

    2016-01-01

    Thedore Oreiser was one of America's greatest writers and one of his famous masterpieces is Sister Carrie. the heroin of the novel was a country girl who struggled for success and finally became a movie star. Analysis on the image of Carrie is of practical significance to the country girls swarming into the city nowdays in our country.

  2. Sisters Hope - Protected by the Fiction

    DEFF Research Database (Denmark)

    Lawaetz, Anna; Hallberg, Gry Worre

    2011-01-01

    In this article we will introduce the fictional and art-pedagogical universe of Sisters Hope and describe how it in different ways transcends into contexts beyond the art world and thus functions as a tool to democratize the aesthetic dimension and mode of being within high schools, academia...

  3. Crocodile Talk: Attributions of Incestuously Abused and Nonabused Sisters.

    Science.gov (United States)

    Monahan, Kathleen

    1997-01-01

    This qualitative study analyzed the retrospective attributions of adult sisters (five abused sister dyads, and five abused and nonabused sister dyads) who grew up in incestuous families. It examined the attributions of subjects regarding the general sibling group; victim selection and nonselection; and attributions regarding jealousy, protection,…

  4. Two Sisters with Idiopathic Pulmonary Hemosiderosis

    Directory of Open Access Journals (Sweden)

    Mehmet Gencer

    2007-01-01

    Full Text Available Idiopathic pulmonary hemosiderosis (IPH is a rare cause of diffuse alveolar hemorrhage with unknown etiology. In the present report, the presentations of two sisters are described: one sister had IPH, eosinophilia and a high serum immunoglobulin E (IgE level; and the other had IPH, pneumothorax, eosinophilia and a high serum IgE level. Both cases had quite unusual presentations. The first patient was 23 years of age, and had suffered from dry cough and progressive dyspnea for four years. Her hemoglobin level was 60 g/L, total serum IgE level was 900 U/mL and eosinophilia was 9%. Her chest radiography revealed diffuse infiltration. She died due to respiratory failure. The second patient was 18 years of age. She had also suffered from dry cough and gradually increasing dyspnea for two years. She had partial pneumothorax in the right lung and diffuse infiltration in other pulmonary fields on chest radiography. Her hemoglobin level was 99 g/L, total serum IgE level was 1200 U/mL and eosinophilia was 8%. IPH was diagnosed by open lung biopsy. All these findings suggested that familial or allergic factors, as well as immunological factors, might have contributed to the etiology of IPH.

  5. Effects of caffeine on sister chromatid exchange (SCE) after exposure to uv light or triaziquone studied with a fluorescence plus giemsa (FPG) technique

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, W.; Bauknecht, T.

    1978-01-19

    Studies are reported that are designed to analyze the mechanism by which caffeine reduces the induction of SCE by uv light or alkylating agents. The substantial points are (1) caffeine does not inhibit SCE formatin, and (2) the caffeine-mediated apparent decrease of SCE induction after uv or triaziquone, exposure is due to a selective destruction of those metaphases otherwise exhibiting a high number of SCE. These findings and their relevance to the ascertainment of the SCE-forming process are discussed.

  6. Cold-sensitive and caffeine-supersensitive mutants of the Schizosaccharomyces pombe dis genes implicated in sister chromatid separation during mitosis.

    OpenAIRE

    Ohkura,H.; Adachi, Y.; Kinoshita, N; Niwa, O; TODA, T.; Yanagida, M

    1988-01-01

    We isolated novel classes of Schizosaccharomyces pombe cold-sensitive dis mutants that block mitotic chromosome separation (nine mapped in the dis1 gene and one each in the dis2 and dis3 genes). Defective phenotype at restrictive temperature is similar among the mutants; the chromosomes condense and anomalously move to the cell ends in the absence of their disjoining so that they are unequally distributed at the two cell ends. Synchronous culture analyses indicate that the cells can enter int...

  7. 12. Chromosomal aberrations and sister chromatid exchanges in the symptomatic individuals exposed to arsenic through drinking water in West Bengal, India

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@In the seven districts of West Bengal, India arsenic in ground water has been found to be above the permissible limit. The concentrations of arsenic is ranging from 200-800 (g/l according to latest reports. More than 200,000 people have already shown different types of arsenical skin lesions in these seven districts of West Bengal. It has been regarded as the biggest arsenic calamity in the world. However, there is

  8. EarthLabs Meet Sister Corita Kent

    Science.gov (United States)

    Quartini, E.; Ellins, K. K.; Cavitte, M. G.; Thirumalai, K.; Ledley, T. S.; Haddad, N.; Lynds, S. E.

    2013-12-01

    The EarthLabs project provides a framework to enhance high school students' climate literacy and awareness of climate change. The project provides climate science curriculum and teacher professional development, followed by research on students' learning as teachers implement EarthLabs climate modules in the classroom. The professional development targets high school teachers whose professional growth is structured around exposure to current climate science research, data observation collection and analysis. During summer workshops in Texas and Mississippi, teachers work through the laboratories, experiments, and hand-on activities developed for their students. In summer 2013, three graduate students from the University of Texas at Austin Institute for Geophysics with expertise in climate science participated in two weeklong workshops. The graduate students partnered with exemplary teacher leaders to provide scientific content and lead the EarthLabs learning activities. As an experiment, we integrated a visit to the Blanton Museum and an associated activity in order to motivate participants to think creatively, as well as analytically, about science. This exercise was inspired by the work and educational philosophy of Sister Corita Kent. During the visit to the Blanton Museum, we steered participants towards specific works of art pre-selected to emphasize aspects of the climate of Texas and to draw participants' attention to ways in which artists convey different concepts. For example, artists use of color, lines, and symbols conjure emotional responses to imagery in the viewer. The second part of the exercise asked participants to choose a climate message and to convey this through a collage. We encouraged participants to combine their experience at the museum with examples of Sister Corita Kent's artwork. We gave them simple guidelines for the project based on techniques and teaching of Sister Corita Kent. Evaluation results reveal that participants enjoyed the

  9. Sister Carrie, an Adherent of Desires

    Institute of Scientific and Technical Information of China (English)

    裴水妹

    2007-01-01

    Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.

  10. Sister Carrie:A Material Pursuer

    Institute of Scientific and Technical Information of China (English)

    马春花

    2015-01-01

    Sister Carrie dramatized by Dreiser is totally a material pursuer. She is selfish and accumulates money in a crazy way. What she does inevitably centers on materials. Living with Drouet and later Hurstwood, Carrie gets what she wants and enjoys the luxurious life in an easy way. However, with the satisfaction of some of her desires, Carrie ’s desires grow and expand. With enough food and clothes, she needs luxury. Hurstwood’s failure in business leads Carrie to the stage and finally she makes a suc⁃cess and becomes a famous actress in Broadway. She gets more money, but her desires grow even higher. Nothing can satisfy her. In this essay, the author tries to analyze Carrie according to Freud’s and Guo Weilu’s theories and prove that Carrie is totally a material pursuer.

  11. A Feminist Reading of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    Wang; Jiatong

    2015-01-01

    In the history of American literature,Sister Carrie is the first novel of Theodore Dreiser,it impresses people deeply.Carrie,a poor country girl,becomes a famous star in a big city.She has totally changed from her hard experiences,and she becomes financially independent as a new woman when she goes through hesitation.In he whole novel,the author has planted some strong points of Carrie’s character.At the end of this paper,it analyzes woman’s status in modern time from two aspects of the improvement of female’s social status and the comparison between men and women.

  12. Interpretations of the Image of Caroline in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    钱绘

    2014-01-01

    In the history of American naturalistic literature, Sister Carrie is a representative work of this literary genre. And the protagonist of this novel Caroline has always been a controversial character. Based on Sister Carrie and the social background of that period in America, this paper discussed the various interpretations of the image of Carrie from different aspects.

  13. Uncoupling of Sister Replisomes during Eukaryotic DNA Replication

    NARCIS (Netherlands)

    Yardimci, Hasan; Loveland, Anna B.; Habuchi, Satoshi; van Oijen, Antoine M.; Walter, Johannes C.

    2010-01-01

    The duplication of eukaryotic genomes involves the replication of DNA from multiple origins of replication. In S phase, two sister replisomes assemble at each active origin, and they replicate DNA in opposite directions. Little is known about the functional relationship between sister replisomes.

  14. Uncoupling of Sister Replisomes during Eukaryotic DNA Replication

    NARCIS (Netherlands)

    Yardimci, Hasan; Loveland, Anna B.; Habuchi, Satoshi; van Oijen, Antoine M.; Walter, Johannes C.

    2010-01-01

    The duplication of eukaryotic genomes involves the replication of DNA from multiple origins of replication. In S phase, two sister replisomes assemble at each active origin, and they replicate DNA in opposite directions. Little is known about the functional relationship between sister replisomes. So

  15. The Disillusion of American Dream in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    张晴

    2016-01-01

    Dreiser is a generally acknowledged writer as one of American's literary naturalists. In Sister Carrie, the author skillfully used the naturalistic writing style which incisively and vividly showed the society environment at that time. The paper states the process that how the American dream in Sister Carrie disillusioned gradually.

  16. Hypersensitivity to G/sub 2/ chromatid radiation damage in familial dysplastic naevus syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Sanford, K.K.; Tarone, R.E.; Parshad, Ram; Tucker, M.A.; Greene, M.H.; Jones, G.M.

    1987-11-14

    Skin fibroblasts from 25 members of nine kindreds with familial dysplastic naevus syndrome (DNS), 12 apparently normal spouses, and 11 additional unrelated normal individuals were tested for G/sub 2/ cell-cycle phase sensitivity to ionising radiation. The cells from individuals with DNS or hereditary cutaneous malignant melanoma with DNS (HCMM/DNS) had significantly more chromatid breaks and gaps when entering metaphase 0.5-1.5 h after G/sub 2/ phase X-irradiation (1 Gy) than those from unaffected controls. In two cases, the test results positively identified individuals before the clinical diagnosis of DNS. A clinically normal obligate carrier of the HCMM/DNS gene showed the enhanced G/sub 2/ radiosensitivity. Moreover, in a test on 1 proband, the sensitivity was apparent in peripheral blood lymphoblasts. Enhanced G/sub 2/ chromatid radiosensitivity may be a marker of genetic susceptibility to HCMM/DNS.

  17. Sister Cities and Economic Development: A New Zeeland Perspective

    Directory of Open Access Journals (Sweden)

    Brian CROSS

    2010-06-01

    Full Text Available Sister City relationships, originally built on cultural understanding and peace through citizen diplomacy, are evolving in today’s society. Politicians increasingly demand real returns where local government is actively involved. Meaningful sister city links are an asset for any community and its nation. However full utilisation requires skills and commitment talked about but often lacking in delivery. Increased emphasis on economic development as primary motivator for having sister cities provides opportunities, but also presents risks as policy emphasis shifts from relationship-building to pragmatic, shorter term goals. New Zealand’s portfolio of sister cities reflect its place on the Pacific Rim and its political/ economic positioning as “part of Asia”. An upsurge in interest from and in China as the place to do business has coincided with a levelling off of sister city activities when they should be increasing. The reasons are varied, but demonstrate the challenges New Zealand faces in continuing as a front-runner in the sister city movement. Sister city policies require honest assessment. Limited resources demand better investment where opportunities are identified or disassociation where they are not. Success requires robust policy development, professionalism and an effective public relations campaign informing communities concerned of the possibilities their international links can present.

  18. Creating Sister Cities: An Exchange Across Hemispheres

    Science.gov (United States)

    Adams, M. T.; Cabezon, S. A.; Hardy, E.; Harrison, R. J.

    2008-06-01

    Sponsored by Associated Universities, Inc. (AUI) and the National Radio Astronomy Observatory (NRAO), this project creates a cultural and educational exchange program between communities in South and North America, linking San Pedro de Atacama in Chile and Magdalena, New Mexico in the United States. Both communities have similar demographics, are in relatively undeveloped regions of high-elevation desert, and are located near major international radio astronomy research facilities. The Atacama Large Millimeter/submillimeter Array (ALMA) is just 40 km east of San Pedro; the Very Large Array (VLA) is just 40 km west of Magdalena. In February 2007, the Mayor of San Pedro and two teachers visited Magdalena for two weeks; in July 2007 three teachers from Magdalena will visit San Pedro. These visits enable the communities to lay the foundation for a permanent, unique partnership. The teachers are sharing expertise and teaching methodologies for physics and astronomy. In addition to creating science education opportunities, this project offers students linguistic and cultural connections. The town of San Pedro, Chile, hosts nearly 100,000 tourists per year, and English language skills are highly valued by local students. Through exchanges enabled by email and distance conferencing, San Pedro and Magdalena students will improve English and Spanish language skills while teaching each other about science and their respective cultures. This poster describes the AUI/NRAO Sister Cities program, including the challenges of cross-cultural communication and the rewards of interpersonal exchanges between continents and cultures.

  19. Mars' atmosphere: Earth's sister and statistical twin

    Science.gov (United States)

    Chen, Wilbur; Lovejoy, Shaun; Muller, Jan-Peter

    2016-04-01

    Satellite-based Martian re-analyses have allowed unprecedented comparisons between our atmosphere and that of our sister planet, underlining various similarities and differences in their respective dynamics. Yet by focusing on large scale structures and deterministic mechanisms they have improved our understanding of the dynamics only over fairly narrow ranges of (near) planetary scales. However, the Reynolds numbers of the flows on both planets are larger than 1011 and dissipation only occurs at centimetric (Mars) or millimetric scales (Earth) so that over most of their scale ranges, the dynamics are fully turbulent. In this presentation, we therefore examine the high level, statistical, turbulent laws for the temperature, horizontal wind and surface pressure, finding that Earth and Mars have virtually identical statistical exponents: their statistics are very similar over wide ranges. Therefore, it would seem that with the exception of certain aspects of the largest scales (such as the role of dust in atmospheric heating on Mars, or of water in its various phases on Earth), that the nonlinear dynamics are very similar. We argue that this is a prediction of the classical laws of turbulence when extended to planetary scales, and that it supports our use of turbulent laws on both planetary atmospheres.

  20. Horsetails are the sister group to all other monilophytes and Marattiales are sister to leptosporangiate ferns.

    Science.gov (United States)

    Knie, Nils; Fischer, Simon; Grewe, Felix; Polsakiewicz, Monika; Knoop, Volker

    2015-09-01

    The "Monilophyte" clade comprising ferns, horsetails and whisk ferns receives unequivocal support from molecular data as the sister clade to seed plants. However, the branching order of its earliest emerging lineages, the Equisetales (horsetails), the Marattiales, the Ophioglossales/Psilotales and the large group of leptosporangiate ferns has remained dubious. We investigated the mitochondrial nad2 and rpl2 genes as two new, intron-containing loci for a wide sampling of taxa. We found that both group II introns - nad2i542g2 and rpl2i846g2 - are universally present among monilophytes. Both introns have orthologues in seed plants where nad2i542g2 has evolved into a trans-arrangement. In contrast and despite substantial size extensions to more than 5kb in Psilotum, nad2i542g2 remains cis-arranged in the monilophytes. For phylogenetic analyses, we filled taxonomic gaps in previously investigated mitochondrial (atp1, nad5) and chloroplast (atpA, atpB, matK, rbcL, rps4) loci and created a 9-gene matrix that also included the new mitochondrial nad2 and rpl2 loci. We extended the taxon sampling with two taxa each for all land plant outgroups (liverworts, mosses, hornworts, lycophytes and seed plants) to minimize the risk of phylogenetic artefacts. We ultimately obtained a well-supported molecular phylogeny placing Marattiales as sister to leptosporangiate ferns and horsetails as sister to all remaining monilophytes. In addition, an indel in an exon of the here introduced rpl2 locus independently supports the placement of horsetails. We conclude that under dense taxon sampling, phylogenetic information from a prudent choice of loci is currently superior to character-rich phylogenomic approaches at low taxon sampling. As here shown the selective choice of loci and taxa enabled us to resolve the long-enigmatic diversifications of the earliest monilophyte lineages.

  1. Developing skills in clinical leadership for ward sisters.

    Science.gov (United States)

    Fenton, Katherine; Phillips, Natasha

    The Francis report has called for a strengthening of the ward sister's role. It recommends that sisters should operate in a supervisory capacity and should not be office bound. Effective ward leadership has been recognised as being vital to high-quality patient care and experience, resource management and interprofessional working. However, there is evidence that ward sisters are ill equipped to lead effectively and lack confidence in their ability to do so. University College London Hospitals Foundation Trust has recognised that the job has become almost impossible in increasingly large and complex organisations. Ward sisters spend less than 40% of their time on clinical leadership and the trust is undertaking a number of initiatives to support them in this role.

  2. CPAFFC Delegation Attends Annual Conference Of Australia Sister Cities Association

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>At the invitation of the Australia Sister Cities Association(ASCA),the CPAFFC delegation visited Australia and attended the Annual Conference of ASCA in Devonport of Tasmania State from November 11 to 22,2006.

  3. Keynote: Sisters Academy. Intervenerende performancepraksis og sanselig uddannelse

    DEFF Research Database (Denmark)

    Hallberg, Gry Worre

    2016-01-01

    Med udgangspunkt i egen intervenerende performancepraksis forankret i visionen om et mere sanseligt samfund, og mere specifikt med det performative uddannelsesudviklingsprojekt Sisters Academy som case, belyses og diskuteres det, hvordan vi kan bruge performancekunst, som en eksperimenterende...

  4. Sister Callista Roy适应模式的应用

    Institute of Scientific and Technical Information of China (English)

    邢映影

    2002-01-01

    @@ 麻省Boston学院的护士理论家Sister Callista Roy,RN,Ph,D曾发表了、和等著作,提出并讨论了Sister Callista Roy适应模式.本文对该模式简单介绍并举例说明其应用,提出一点体会,供学习和应用借鉴.

  5. Two sisters resembling Gorlin-Chaudhry-Moss syndrome.

    Science.gov (United States)

    Aravena, Teresa; Passalacqua, Cristóbal; Pizarro, Oscar; Aracena, Mariana

    2011-10-01

    The Gorlin-Chaudhry-Moss syndrome (GCMS), was describe initially by Gorlin et al. [Gorlin et al. (1960)] in two sisters with craniosynostosis, hypertrichosis, hypoplastic labia majora, dental defects, eye anomalies, patent ductus arteriosus, and normal intelligence. Two other sporadic instances have been documented. Here, we report on two sisters with a condition with some similarities to GCMS as well as some differences, which could represent either previously unreported variability in GCMS, or it may represent a novel disorder.

  6. Sisters of St. Dorothy: an answer? (1866-1910

    Directory of Open Access Journals (Sweden)

    Ir. Diana Barbosa

    2016-12-01

    Full Text Available Implantation of the Congregation of the Sisters of St.  Dorothy inPortugal. Initial difficulties. New answers. Paula Frassinetti visits the Sisters. Development of the Institute inPortugal. Foundations: 1875-1910. Development of theCollegeofQuelhas.The Religious Persecution of 1901. The Revolution of October 1910 and the expulsion. Dispersion.Keywords  Dorothy;Portugal; Education;  Expansion.

  7. Geographic variance of cardiovascular risk factors among community women: the national Sister to Sister campaign.

    Science.gov (United States)

    Jarvie, Jennifer L; Johnson, Caitlin E; Wang, Yun; Wan, Yun; Aslam, Farhan; Athanasopoulos, Leonidas V; Pollin, Irene; Foody, JoAnne M

    2011-01-01

    There are substantial variations in cardiovascular disease (CVD) risk and outcomes among women. We sought to determine geographic variation in risk factor prevalence in a contemporary sample of U.S. women. Using 2008-2009 Sister to Sister (STS) free heart screening data from 17 U.S. cities, we compared rates of obesity (body mass index [BMI] ≥30 kg/m(2)), hypertension (HTN ≥140/90 mm Hg), low high-density lipoprotein cholesterol (HDL-C national rates. In 18,892 women (mean age 49.8 ± 14.3 years, 37% black, 32% white, 14% Hispanic), compared to overall STS rates, significantly higher rates were observed for obesity in Baltimore (42.4%), Atlanta (40.0%), Dallas (37.9%), and Jacksonville (36.0%); for HTN in Atlanta (43.9%), Baltimore (42.5%), and New York (39.1%); for hyperglycemia in Jacksonville (20.3%), Philadelphia (18.1%), and Tampa (17.8%); and for HDL-C national American Heart Association (AHA) 2010 update rates, most STS cities had higher rates of hyperglycemia and low HDL-C. In a large, community-based sample of women nationwide, this comprehensive analysis shows remarkable geographic variation in risk factors, which provides opportunities to improve and reduce a woman's CVD risk. Further investigation is required to understand the reasons behind such variation, which will provide insight toward tailoring preventive interventions to narrow gaps in CVD risk reduction in women.

  8. Teenage pregnancy: the impact of maternal adolescent childbearing and older sister's teenage pregnancy on a younger sister.

    Science.gov (United States)

    Wall-Wieler, Elizabeth; Roos, Leslie L; Nickel, Nathan C

    2016-05-25

    Risk factors for teenage pregnancy are linked to many factors, including a family history of teenage pregnancy. This research examines whether a mother's teenage childbearing or an older sister's teenage pregnancy more strongly predicts teenage pregnancy. This study used linkable administrative databases housed at the Manitoba Centre for Health Policy (MCHP). The original cohort consisted of 17,115 women born in Manitoba between April 1, 1979 and March 31, 1994, who stayed in the province until at least their 20(th) birthday, had at least one older sister, and had no missing values on key variables. Propensity score matching (1:2) was used to create balanced cohorts for two conditional logistic regression models; one examining the impact of an older sister's teenage pregnancy and the other analyzing the effect of the mother's teenage childbearing. The adjusted odds of becoming pregnant between ages 14 and 19 for teens with at least one older sister having a teenage pregnancy were 3.38 (99 % CI 2.77-4.13) times higher than for women whose older sister(s) did not have a teenage pregnancy. Teenage daughters of mothers who had their first child before age 20 had 1.57 (99 % CI 1.30-1.89) times higher odds of pregnancy than those whose mothers had their first child after age 19. Educational achievement was adjusted for in a sub-population examining the odds of pregnancy between ages 16 and 19. After this adjustment, the odds of teenage pregnancy for teens with at least one older sister who had a teenage pregnancy were reduced to 2.48 (99 % CI 2.01-3.06) and the odds of pregnancy for teen daughters of teenage mothers were reduced to 1.39 (99 % CI 1.15-1.68). Although both were significant, the relationship between an older sister's teenage pregnancy and a younger sister's teenage pregnancy is much stronger than that between a mother's teenage childbearing and a younger daughter's teenage pregnancy. This study contributes to understanding of the broader topic "who is

  9. little sister: An Afro-Temporal Solo-Play.

    Science.gov (United States)

    De Berry, Misty

    2016-09-12

    little sister: An Afro-Temporal Solo-Play is at once a memory-scape and a mytho-biography set to poetry, movement, and mixed media. A performance poem spanning from the Antebellum South to present-moment Chicago, it tells the story of a nomadic spirit named little-she who shape-shifts through the memories and imaginings of her sister, the narrator. Through the characters little-she and the narrator, the solo-performance explores embodied ways to rupture and relieve the impact of macro forms of violence in the micro realm of the everyday. To this end, little sister witnesses and disrupts the legacy of violence in the lives of queer Black women through a trans-temporal navigation of everyday encounters within familial, small groups and intimate partner spaces.

  10. Familial acromegaly - case study of two sisters with acromegaly.

    Science.gov (United States)

    Malicka, Joanna; Świrska, Joanna; Nowakowski, Andrzej

    2011-01-01

    In the majority of cases, acromegaly is sporadic. However, it can also occur in a familial setting as a component of MEN-1, MEN-4, Carney complex (CNC) or as the extremely rare syndrome of isolated familial somatotropinoma (IFS), the latter belonging to familial isolated pituitary adenomas (FIPA). The diagnosis of IFS is based on the recognition of acromegaly/gigantism in at least two family members, given that the family is not affected by MEN-1, MEN-4 or CNC. The authors present a case study of two sisters: a 56 year-old patient (case no. 1) and a 61 year-old patient (case no. 2). In both sisters, acromegaly was recognised in the course of pituitary macroadenoma. Neither of the sisters showed features of MEN-1, MEN-4 or Carney complex. The authors suppose that the presented cases are manifestations of IFS. However, this diagnosis has not been confirmed yet because of the poor availability of genetic tests.

  11. [Florence Nightingale and charity sisters: revisiting the history].

    Science.gov (United States)

    Padilha, Maria Itayra Coelho de Souza; Mancia, Joel Rolim

    2005-01-01

    This study presents an historical analysis on the links between the nursing practice and the influence received from various religious orders/associations along the times, especially from Saint Vincent Paul's charity sisters. The professional nursing which was pioneered by Florence Nightingale in the XlXth century, was directly influenced by the teachings of love and fraternity. In addition, other contributions from the religious orders/associations were the concepts of altruism, valorization of an adequate environment for the care of patients, and the division of work in nursing. The study shows the influence of Charity Sisters on Florence Nightingale.

  12. Letters from a suicide: Van Gogh and his sister.

    Science.gov (United States)

    Lester, David

    2010-04-01

    An analysis of trends over a 3-yr. period in the letters of Vincent Van Gogh to his sister as the time of his suicide approached identified 8 trends, including an increase in words concerned with anxiety and words concerned with the past.

  13. Sister M. Madeleva Wolff, C.S.C.

    Science.gov (United States)

    Petit, M. Loretta

    2006-01-01

    Sister M. Madeleva Wolff, C.S.C., teacher, essayist, poet, and college administrator, through her creative ability and innovative practices made possible major contributions to Catholic education in her lifetime. Without her strong personality and boundless energy, many of her dreams for an ideal college curriculum would not have come to fruition.…

  14. Some Effects of Having a Brother or Sister.

    Science.gov (United States)

    Leventhal, Gerald S.

    The data indicate that the influence of a brother or sister is considerably greater upon the second born than upon the first born. The magnitude of the sex of sibling effect is probably dependent upon whether a sibling is present during the first few years of life, a period during which many enduring response patterns are being acquired. The…

  15. El naturalismo americano: Theodore Dreiser y Sister Carrie

    Directory of Open Access Journals (Sweden)

    Dolores G. ALONSO MULAS

    2009-08-01

    Full Text Available Para situar a un escritor, como Theodore Dreiser, y especialmente su novela Sister Carrie dentro de un movimiento literario y de una etapa determinada de la historia americana, es necesario dar un breve repaso al naturalismo, llegado a América a través de Stephen Crane

  16. Freud on Brothers and Sisters: A Neglected Topic

    Science.gov (United States)

    Sherwin-White, Susan

    2007-01-01

    This paper explores Freud's developing thought on brothers and sisters, and their importance in his psychoanalytical writings and clinical work. Freud's work on sibling psychology has been seriously undervalued. This paper aims to give due recognition to Freud's work in this area. (Contains 1 note.)

  17. The Lehman Sisters Hypothesis: an exploration of literature and bankers

    NARCIS (Netherlands)

    I.P. van Staveren (Irene)

    2012-01-01

    textabstractThis article tests the Lehman Sisters Hypothesis in two complementary, although incomplete ways. It reviews the diverse empirical literature in behavioural, experimental, and neuroeconomics as well as related fields of behavioural research. And it presents the findings from an explorativ

  18. The Lehman Sisters Hypothesis: an exploration of literature and bankers

    NARCIS (Netherlands)

    I.P. van Staveren (Irene)

    2012-01-01

    textabstractAbstract This article tests the Lehman Sisters Hypothesis in two complementary, although incomplete ways. It reviews the diverse empirical literature in behavioral, experimental, and neuroeconomics as well as related fields of behavioral research. And it presents the findings from an exp

  19. 写作风景线 My Sister

    Institute of Scientific and Technical Information of China (English)

    尹姗姗; 高现华; 刘占华

    2004-01-01

    I ave a pretty sister.She’s fourteen years old.Shestudies hard.So she sets agood example to me.Shersgetting on well with her class-mates and her teachers. Shelikes maths and Chinese,andshe's good at them.She likesdancing and music very much.

  20. The Lehman Sisters Hypothesis: an exploration of literature and bankers

    NARCIS (Netherlands)

    I.P. van Staveren (Irene)

    2012-01-01

    textabstractThis article tests the Lehman Sisters Hypothesis in two complementary, although incomplete ways. It reviews the diverse empirical literature in behavioural, experimental, and neuroeconomics as well as related fields of behavioural research. And it presents the findings from an

  1. The Lehman Sisters Hypothesis: an exploration of literature and bankers

    NARCIS (Netherlands)

    I.P. van Staveren (Irene)

    2012-01-01

    textabstractAbstract This article tests the Lehman Sisters Hypothesis in two complementary, although incomplete ways. It reviews the diverse empirical literature in behavioral, experimental, and neuroeconomics as well as related fields of behavioral research. And it presents the findings from an

  2. The Broken American Dream Based on Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    Dong Wenjuan

    2012-01-01

      Sister Carrie is the first work of Theodore Dreiser, It tells us how a country maiden becomes a famous star in Broadway. In the novel, Dreiser describes the living conditions and emotion changes of Carrie very vividly. Sister Carrie takes true realism as its distinctive feature, reflects the tragic fact that people pursue American dream fanatically in the early twentieth century. This paper exposes the theme of instinct, which drives people to enjoy but disillusion finally, and illustrates that it is impossible to possess true happiness in a money-oriented capitalism society%  Sister Carrie is the first work of Theodore Dreiser, Ittells us how a country maiden becomes a famous star in Broadway.In the novel, Dreiser describes the living conditions and emotion changes of Carrie very vividly. Sister Carrie takes true realism as itsdistinctive feature, reflects the tragic fact that people pursue Americandream fanatically in the early twentieth century. This paper exposes the theme of instinct, which drives people to enjoy but disillusion finally, and illustrates that it is impossible to possess true happiness in a money-oriented capitalism society

  3. Adult Sibling Relationships with Brothers and Sisters with Severe Disabilities

    Science.gov (United States)

    Rossetti, Zach; Hall, Sarah

    2015-01-01

    The purpose of this qualitative study was to examine perceptions of adult sibling relationships with a brother or sister with severe disabilities and the contexts affecting the relationships. Adult siblings without disabilities (N = 79) from 19 to 72 years of age completed an online survey with four open-ended questions about their relationship…

  4. Freud on Brothers and Sisters: A Neglected Topic

    Science.gov (United States)

    Sherwin-White, Susan

    2007-01-01

    This paper explores Freud's developing thought on brothers and sisters, and their importance in his psychoanalytical writings and clinical work. Freud's work on sibling psychology has been seriously undervalued. This paper aims to give due recognition to Freud's work in this area. (Contains 1 note.)

  5. Meiosis-specific cohesin component, Stag3 is essential for maintaining centromere chromatid cohesion, and required for DNA repair and synapsis between homologous chromosomes.

    Directory of Open Access Journals (Sweden)

    Jessica Hopkins

    2014-07-01

    Full Text Available Cohesins are important for chromosome structure and chromosome segregation during mitosis and meiosis. Cohesins are composed of two structural maintenance of chromosomes (SMC1-SMC3 proteins that form a V-shaped heterodimer structure, which is bridged by a α-kleisin protein and a stromal antigen (STAG protein. Previous studies in mouse have shown that there is one SMC1 protein (SMC1β, two α-kleisins (RAD21L and REC8 and one STAG protein (STAG3 that are meiosis-specific. During meiosis, homologous chromosomes must recombine with one another in the context of a tripartite structure known as the synaptonemal complex (SC. From interaction studies, it has been shown that there are at least four meiosis-specific forms of cohesin, which together with the mitotic cohesin complex, are lateral components of the SC. STAG3 is the only meiosis-specific subunit that is represented within all four meiosis-specific cohesin complexes. In Stag3 mutant germ cells, the protein level of other meiosis-specific cohesin subunits (SMC1β, RAD21L and REC8 is reduced, and their localization to chromosome axes is disrupted. In contrast, the mitotic cohesin complex remains intact and localizes robustly to the meiotic chromosome axes. The instability of meiosis-specific cohesins observed in Stag3 mutants results in aberrant DNA repair processes, and disruption of synapsis between homologous chromosomes. Furthermore, mutation of Stag3 results in perturbation of pericentromeric heterochromatin clustering, and disruption of centromere cohesion between sister chromatids during meiotic prophase. These defects result in early prophase I arrest and apoptosis in both male and female germ cells. The meiotic defects observed in Stag3 mutants are more severe when compared to single mutants for Smc1β, Rec8 and Rad21l, however they are not as severe as the Rec8, Rad21l double mutants. Taken together, our study demonstrates that STAG3 is required for the stability of all meiosis

  6. Meiosis-specific cohesin component, Stag3 is essential for maintaining centromere chromatid cohesion, and required for DNA repair and synapsis between homologous chromosomes.

    Science.gov (United States)

    Hopkins, Jessica; Hwang, Grace; Jacob, Justin; Sapp, Nicklas; Bedigian, Rick; Oka, Kazuhiro; Overbeek, Paul; Murray, Steve; Jordan, Philip W

    2014-07-01

    Cohesins are important for chromosome structure and chromosome segregation during mitosis and meiosis. Cohesins are composed of two structural maintenance of chromosomes (SMC1-SMC3) proteins that form a V-shaped heterodimer structure, which is bridged by a α-kleisin protein and a stromal antigen (STAG) protein. Previous studies in mouse have shown that there is one SMC1 protein (SMC1β), two α-kleisins (RAD21L and REC8) and one STAG protein (STAG3) that are meiosis-specific. During meiosis, homologous chromosomes must recombine with one another in the context of a tripartite structure known as the synaptonemal complex (SC). From interaction studies, it has been shown that there are at least four meiosis-specific forms of cohesin, which together with the mitotic cohesin complex, are lateral components of the SC. STAG3 is the only meiosis-specific subunit that is represented within all four meiosis-specific cohesin complexes. In Stag3 mutant germ cells, the protein level of other meiosis-specific cohesin subunits (SMC1β, RAD21L and REC8) is reduced, and their localization to chromosome axes is disrupted. In contrast, the mitotic cohesin complex remains intact and localizes robustly to the meiotic chromosome axes. The instability of meiosis-specific cohesins observed in Stag3 mutants results in aberrant DNA repair processes, and disruption of synapsis between homologous chromosomes. Furthermore, mutation of Stag3 results in perturbation of pericentromeric heterochromatin clustering, and disruption of centromere cohesion between sister chromatids during meiotic prophase. These defects result in early prophase I arrest and apoptosis in both male and female germ cells. The meiotic defects observed in Stag3 mutants are more severe when compared to single mutants for Smc1β, Rec8 and Rad21l, however they are not as severe as the Rec8, Rad21l double mutants. Taken together, our study demonstrates that STAG3 is required for the stability of all meiosis-specific cohesin

  7. Meiosis-specific cohesin component, Stag3 is essential for maintaining centromere chromatid cohesion, and required for DNA repair and synapsis between homologous chromosomes.

    Directory of Open Access Journals (Sweden)

    Jessica Hopkins

    2014-07-01

    Full Text Available Cohesins are important for chromosome structure and chromosome segregation during mitosis and meiosis. Cohesins are composed of two structural maintenance of chromosomes (SMC1-SMC3 proteins that form a V-shaped heterodimer structure, which is bridged by a α-kleisin protein and a stromal antigen (STAG protein. Previous studies in mouse have shown that there is one SMC1 protein (SMC1β, two α-kleisins (RAD21L and REC8 and one STAG protein (STAG3 that are meiosis-specific. During meiosis, homologous chromosomes must recombine with one another in the context of a tripartite structure known as the synaptonemal complex (SC. From interaction studies, it has been shown that there are at least four meiosis-specific forms of cohesin, which together with the mitotic cohesin complex, are lateral components of the SC. STAG3 is the only meiosis-specific subunit that is represented within all four meiosis-specific cohesin complexes. In Stag3 mutant germ cells, the protein level of other meiosis-specific cohesin subunits (SMC1β, RAD21L and REC8 is reduced, and their localization to chromosome axes is disrupted. In contrast, the mitotic cohesin complex remains intact and localizes robustly to the meiotic chromosome axes. The instability of meiosis-specific cohesins observed in Stag3 mutants results in aberrant DNA repair processes, and disruption of synapsis between homologous chromosomes. Furthermore, mutation of Stag3 results in perturbation of pericentromeric heterochromatin clustering, and disruption of centromere cohesion between sister chromatids during meiotic prophase. These defects result in early prophase I arrest and apoptosis in both male and female germ cells. The meiotic defects observed in Stag3 mutants are more severe when compared to single mutants for Smc1β, Rec8 and Rad21l, however they are not as severe as the Rec8, Rad21l double mutants. Taken together, our study demonstrates that STAG3 is required for the stability of all meiosis

  8. Mercury poisoning in two 13-year-old twin sisters

    OpenAIRE

    Ezzat Khodashenas; Mohammadhassan Aelami; Mahdi Balali-Mood

    2015-01-01

    Mercury (Hg) is a toxic agent that evaporates in room temperature and its inhalation may cause poisoning. Due to the nonspecific symptoms, diagnosis is difficult in special circumstances with no initial history of Hg exposure. We report two such cases of Hg poisoning. The patients were two sisters, presenting with pain in extremities, itchy rashes, sweating, salivation, weakness, and mood changes. They have used a compound that contains mercury, for treatment of pedicullosis three months befo...

  9. The Construction of Social Darwinism in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    薛晶晶; 秦素华

    2014-01-01

    Social Darwinism is an important theory reflected in Sister Carrie. This thesis is to interpret the characters’fates with Social Darwinism.“Survival of the fittest”is an important theme. Carrie is the winner of life and Hurtwood is the loser. Their adjustability to the environment determines their future. It is hoped to help the readers construct a better understanding on this theory.

  10. Autosomal recessive limb girdle myasthenia in two sisters.

    Directory of Open Access Journals (Sweden)

    Shankar A

    2002-10-01

    Full Text Available Limb girdle myasthenic syndromes are rare genetic disorders described under the broad heterogeneous group known as congenital myasthenic syndromes and present with mixed features of myasthenia and myopathy. The familial limb girdle myasthenia has been described as one with selective weakness of pectoral and pelvic girdles, showing a positive response to edrophonium chloride. A report of two sisters affected by this disorder is presented.

  11. Cell killing and chromatid damage in primary human bronchial epithelial cells irradiated with accelerated 56Fe ions

    Science.gov (United States)

    Suzuki, M.; Piao, C.; Hall, E. J.; Hei, T. K.

    2001-01-01

    We examined cell killing and chromatid damage in primary human bronchial epithelial cells irradiated with high-energy 56Fe ions. Cells were irradiated with graded doses of 56Fe ions (1 GeV/nucleon) accelerated with the Alternating Gradient Synchrotron at Brookhaven National Laboratory. The survival curves for cells plated 1 h after irradiation (immediate plating) showed little or no shoulder. However, the survival curves for cells plated 24 h after irradiation (delayed plating) had a small initial shoulder. The RBE for 56Fe ions compared to 137Cs gamma rays was 1.99 for immediate plating and 2.73 for delayed plating at the D10. The repair ratio (delayed plating/immediate plating) was 1.67 for 137Cs gamma rays and 1.22 for 56Fe ions. The dose-response curves for initially measured and residual chromatid fragments detected by the Calyculin A-mediated premature chromosome condensation technique showed a linear response. The results indicated that the induction frequency for initially measured fragments was the same for 137Cs gamma rays and 56Fe ions. On the other hand, approximately 85% of the fragments induced by 137Cs gamma rays had rejoined after 24 h of postirradiation incubation; the corresponding amount for 56Fe ions was 37%. Furthermore, the frequency of chromatid exchanges induced by gamma rays measured 24 h after irradiation was higher than that induced by 56Fe ions. No difference in the amount of chromatid damage induced by the two types of radiations was detected when assayed 1 h after irradiation. The results suggest that high-energy 56Fe ions induce a higher frequency of complex, unrepairable damage at both the cellular and chromosomal levels than 137Cs gamma rays in the target cells for radiation-induced lung cancers.

  12. Broad phylogenomic sampling and the sister lineage of land plants.

    Directory of Open Access Journals (Sweden)

    Ruth E Timme

    Full Text Available The tremendous diversity of land plants all descended from a single charophyte green alga that colonized the land somewhere between 430 and 470 million years ago. Six orders of charophyte green algae, in addition to embryophytes, comprise the Streptophyta s.l. Previous studies have focused on reconstructing the phylogeny of organisms tied to this key colonization event, but wildly conflicting results have sparked a contentious debate over which lineage gave rise to land plants. The dominant view has been that 'stoneworts,' or Charales, are the sister lineage, but an alternative hypothesis supports the Zygnematales (often referred to as "pond scum" as the sister lineage. In this paper, we provide a well-supported, 160-nuclear-gene phylogenomic analysis supporting the Zygnematales as the closest living relative to land plants. Our study makes two key contributions to the field: 1 the use of an unbiased method to collect a large set of orthologs from deeply diverging species and 2 the use of these data in determining the sister lineage to land plants. We anticipate this updated phylogeny not only will hugely impact lesson plans in introductory biology courses, but also will provide a solid phylogenetic tree for future green-lineage research, whether it be related to plants or green algae.

  13. Genomic sister-disorders of neurodevelopment: an evolutionary approach.

    Science.gov (United States)

    Crespi, Bernard; Summers, Kyle; Dorus, Steve

    2009-02-01

    Genomic sister-disorders are defined here as diseases mediated by duplications versus deletions of the same region. Such disorders can provide unique information concerning the genomic underpinnings of human neurodevelopment because effects of diametric variation in gene copy number on cognitive and behavioral phenotypes can be inferred. We describe evidence from the literature on deletions versus duplications for the regions underlying the best-known human neurogenetic sister-disorders, including Williams syndrome, Velocardiofacial syndrome, and Smith-Magenis syndrome, as well as the X-chromosomal conditions Klinefelter and Turner syndromes. These data suggest that diametric copy-number alterations can, like diametric alterations to imprinted genes, generate contrasting phenotypes associated with autistic-spectrum and psychotic-spectrum conditions. Genomically based perturbations to the development of the human social brain are thus apparently mediated to a notable degree by effects of variation in gene copy number. We also conducted the first analyses of positive selection for genes in the regions affected by these disorders. We found evidence consistent with adaptive evolution of protein-coding genes, or selective sweeps, for three of the four sets of sister-syndromes analyzed. These studies of selection facilitate identification of candidate genes for the phenotypes observed and lend a novel evolutionary dimension to the analysis of human cognitive architecture and neurogenetic disorders.

  14. Strain gradients and melt pathways, Twin Sisters complex, Washington State

    Science.gov (United States)

    Kruckenberg, S. C.; Newman, J.; Tikoff, B.; Toy, V. G.

    2009-12-01

    The Twin Sisters complex in the North Cascades of Washington state is a large (~6 by 16 km), virtually unaltered ultramafic body that provides information about the relationships between the formation of compositional layering, structural fabrics and the formation of inferred melt pathways in naturally deforming peridotites. Compositional layering is largely defined by alternating layers of orthopyroxene-absent dunite (>95% olivine) and orthopyroxene-present (~15% orthopyroxene; ~85% olivine) harzburgite aligned parallel to a roughly N-S striking and steeply dipping foliation. Orthopyroxene- and clinopyroxene-bearing dikes occur throughout the Twin Sisters and crosscut the host dunite and harzburgite layering. Orthopyroxene dikes range in thickness from 1 cm to >1 m and are variably oriented and may be folded. Clinopyroxene-bearing dikes are thinner, more consistently oriented (~N-S), and generally more tabular than the orthopyroxene dikes. In the Twin Sisters, cm- to m-scale zones of porphyroclastic dunite cross-cut the main dunite-harzburgite compositional layering and display a variety of relationships with pyroxene dikes in the region. These porphyroclastic dunite bands locally contain single olivine grains >10 cm and likely represent former pathways of melt migration. Transect mapping along an E-W traverse across the Twin Sisters massif reveals that these inferred melt channels form at various angles relative to the main dunite-harzburgite layering. In the west, porphyroclastic olivine layers form at low angle to the main foliation and compositional layering. These zone form at systematically higher angles across the structural section of the Twin Sisters massif to the east and commonly form conjugate cross-cutting sets at high-angle to the main N-S dunite-harzburgite layering. This change in band angle correlates broadly with changes in the intensity of folding of orthopyroxene-bearing dikes, with more intensely deformed dikes in the west to more planar dikes

  15. Mutagen sensitivity as measured by induced chromatid breakage as a marker of cancer risk.

    Science.gov (United States)

    Wu, Xifeng; Zheng, Yun-Ling; Hsu, T C

    2014-01-01

    Risk assessment is now recognized as a multidisciplinary process, extending beyond the scope of traditional epidemiologic methodology to include biological evaluation of interindividual differences in carcinogenic susceptibility. Modulation of environmental exposures by host genetic factors may explain much of the observed interindividual variation in susceptibility to carcinogenesis. These genetic factors include, but are not limited to, carcinogen metabolism and DNA repair capacity. This chapter describes a standardized method for the functional assessment of mutagen sensitivity. This in vitro assay measures the frequency of mutagen-induced breaks in the chromosomes of peripheral blood lymphocytes. Mutagen sensitivity assessed by this method has been shown to be a significant risk factor for tobacco-related maladies, especially those of the upper aerodigestive tract. Mutagen sensitivity may therefore be a useful member of a panel of susceptibility markers for defining high-risk subgroups for chemoprevention trials. This chapter describes methods for and discusses results from studies of mutagen sensitivity as measured by quantifying chromatid breaks induced by clastogenic agents, such as the γ-radiation mimetic DNA cross-linking agent bleomycin and chemicals that form so-called bulky DNA adducts, such as 4-nitroquinoline and the tobacco smoke constituent benzo[a]pyrene, in short-term cultured peripheral blood lymphocytes.

  16. Obstetric prognosis in sisters of preeclamptic women – implications for genetic linkage studies

    Directory of Open Access Journals (Sweden)

    Heinonen Seppo

    2003-02-01

    Full Text Available Abstract Background To investigate obstetric prognosis in sisters of preeclamptic women. Methods We identified consecutive 635 sib pairs from the Birth Registry data of Kuopio University Hospital who had their first delivery between January 1989 and December 1999 in our institution. Of these, in 530 pairs both sisters had non-preeclamptic pregnancies (the reference group, in 63 pairs one of the sisters had preeclampsia and the unaffected sisters were studied (study group I. In 42 pairs both sister's first delivery was affected (study group II. Pregnancy outcome measures in these groups were compared. Results Unaffected sisters of the index patients had uncompromised fetal growth in their pregnancies, and overall, as good obstetric outcomes as in the reference group. The data on affected sisters of the index patients showed an increased prematurity rate, and increased incidences of low birth weight and small-for-gestational age infants, as expected. Conclusion Unaffected sisters of the index patients had no signs of utero-placental insufficiency and they were at low risk with regard to adverse obstetric outcome, whereas affected sisters were high-risk. Clinically, affected versus unaffected status appears to be clear-cut in first-degree relatives regardless of their genetic susceptibility and unaffected sisters do not need special antepartum surveillance.

  17. Reflection of Naturalism and Darwinism in Dreiser' s Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    王静

    2009-01-01

    Naturalism is a significant school of literature in American literary history. This thesis mainly reviews the background, development, and characteristic of the realism and naturalism literature, and states the significant person in Naturalism literature-Dreiser and his. important literary position and analyzes the reflection of naturalism and Darwinism in Sister Carrie. Through the analysis of determinism, desire, ethics and detail description, a conclusion is made: the factors affecting the novel' s writing not only include the author' s own experiences but also the main social ideology in his living years.

  18. Dealing with conflict - The role of the ward sister

    Directory of Open Access Journals (Sweden)

    L.M. Cremer

    1980-09-01

    Full Text Available In the course of her duties, the ward sister has to contend with many forms of conflict, discord and dissension. These involve conflict of the intrapersonal, interpersonal and intergroup varieties. Conflict is in the main, disruptive and dysfunctional. Skilful management, however, embodying cooperative effort in its reduction can produce constructive and positive results. Conflict management strategies are therefore either restrictive or constructive. Persons in serious conflict suffer varied degrees of personality disequilibrium, which necessitates emotional first aid or crisis intervention. Such primary preventive care is applicable to patients, their relatives, and members of the nursing staff in such need.

  19. Cortical Pathology in RRMS: Taking a Cue from Four Sisters

    Directory of Open Access Journals (Sweden)

    Massimiliano Calabrese

    2012-01-01

    Full Text Available Background. Although grey matter pathology is a relevant aspect of multiple sclerosis (MS both with physical and cognitive rebounds, its pathogenesis is still under investigation. To what extent the familial and sporadic cases of MS differ in cortical pathology has not been elucidated yet. Here we present a multiple case report of four sisters affected by MS, all of them having a very high burden of cortical pathology. Methods. The clinical and grey matter MRI parameters of the patients were compared with those of twenty-five-aged matched healthy women and 25 women affected by sporadic MS (matched for age, disease duration, EDSS, and white matter lesion load. Results. Despite their short disease duration (<5 years, the four sisters showed a significant cortical thinning compared to healthy controls ( and sporadic MS ( and higher CLs number ( and volume ( compared to sporadic MS. Discussion. Although limited to a single family, our observation is worth of interest since it suggests that familial factors may account for a peculiar involvement of the cortex in MS pathology. This hypothesis should be further evaluated in a large number of multiplex MS families.

  20. Narcolepsy with cataplexy mimicry: the strange case of two sisters.

    Science.gov (United States)

    Pizza, Fabio; Vandi, Stefano; Poli, Francesca; Moghadam, Keivan Kaveh; Franceschini, Christian; Bellucci, Claudia; Cipolli, Carlo; Ingravallo, Francesca; Natalini, Giuliana; Mignot, Emmanuel; Plazzi, Giuseppe

    2013-06-15

    We report on two sisters, 17 and 12 years of age, with clinical features suggesting narcolepsy with cataplexy (NC): daytime sleepiness, spontaneous and emotionally triggered sudden falls to the ground, and overweight/obesity. MSLT showed borderline sleep latency, with 1 and 0 sleep onset REM periods. HLA typing disclosed the DQB1*0602 allele. Video-polygraphy of the spells ruled out NC diagnosis by demonstrating their easy elicitation by suggestion, with wake EEG, electromyographic persistence of muscle tone, and stable presence of tendon reflexes (i.e., pseudo-cataplexy), together with normal cerebrospinal hypocretin-1 levels. Our cases emphasize the need of a clear depiction of cataplexy pattern at the different ages, the usefulness of examining ictal neurophysiology, and collecting all available disease markers in ambiguous cases.

  1. Mercury poisoning in two 13-year-old twin sisters.

    Science.gov (United States)

    Khodashenas, Ezzat; Aelami, Mohammadhassan; Balali-Mood, Mahdi

    2015-03-01

    Mercury (Hg) is a toxic agent that evaporates in room temperature and its inhalation may cause poisoning. Due to the nonspecific symptoms, diagnosis is difficult in special circumstances with no initial history of Hg exposure. We report two such cases of Hg poisoning. The patients were two sisters, presenting with pain in extremities, itchy rashes, sweating, salivation, weakness, and mood changes. They have used a compound that contains mercury, for treatment of pedicullosis three months before admission. This compound was purchased from a herbal shop and was applied locally on the scalps for 2 days. Their urinary mercury concentrations were 50 and 70 mg/L. They were successfully treated by D-penicillamine and gabapentin. In a patient with any kind of bone and joint pain, skin rash erythema and peripheral neuropathy, mercury poisoning should be considered as a differential diagnosis.

  2. Mercury poisoning in two 13-year-old twin sisters

    Directory of Open Access Journals (Sweden)

    Ezzat Khodashenas

    2015-01-01

    Full Text Available Mercury (Hg is a toxic agent that evaporates in room temperature and its inhalation may cause poisoning. Due to the nonspecific symptoms, diagnosis is difficult in special circumstances with no initial history of Hg exposure. We report two such cases of Hg poisoning. The patients were two sisters, presenting with pain in extremities, itchy rashes, sweating, salivation, weakness, and mood changes. They have used a compound that contains mercury, for treatment of pedicullosis three months before admission. This compound was purchased from a herbal shop and was applied locally on the scalps for 2 days. Their urinary mercury concentrations were 50 and 70 mg/L. They were successfully treated by D-penicillamine and gabapentin. In a patient with any kind of bone and joint pain, skin rash erythema and peripheral neuropathy, mercury poisoning should be considered as a differential diagnosis.

  3. A Bangladeshi family with three sisters 'Bombay' or Oh phenotype.

    Science.gov (United States)

    Rahman, M; Abdullah, A Z; Husain, M; Hague, K M; Hossain, M M

    1990-12-01

    Three sisters in a same family (MIAH FAMILY) are of 'Bombay' phenotype. These being the first known female examples of 'Bombay' blood group have been detected in Bangladesh. As predicted by current theory their red cells are Le(a+b-) and their saliva do not contain any of the antigens A, B and H except Lea substance. Family studies showed that individuals with 'Bombay' or Oh phenotype may have A or B gene which are not expressed. This very particular type of blood is one of the rarest in any other parts of world except in India. Due to the presence of anti-H antibody in the plasma of Oh phenotype, when considering such patients for transfusion only blood of identical Bombay type can be safely transfused.

  4. Sister Mary Joseph Nodule as a Presenting Sign of Pancreatobiliary Adenocarcinoma

    OpenAIRE

    2012-01-01

    Sister Mary Joseph nodules represent metastatic cancer of the umbilicus. These malignancies are usually associated with the ovary and gastrointestinal tract. The authors report the case of a Sister Mary Joseph nodule originating from the bifurcation of the common hepatic duct. Umbilical nodules should prompt clinical evaluations, as these tumors are usually associated with poor prognosis.

  5. Sister Mary joseph nodule as a presenting sign of pancreatobiliary adenocarcinoma.

    Science.gov (United States)

    Shelling, Michael L; Vitiello, Magalys; Lanuti, Emma L; Rodriguez, Senen; Kerdel, Francisco A

    2012-10-01

    Sister Mary Joseph nodules represent metastatic cancer of the umbilicus. These malignancies are usually associated with the ovary and gastrointestinal tract. The authors report the case of a Sister Mary Joseph nodule originating from the bifurcation of the common hepatic duct. Umbilical nodules should prompt clinical evaluations, as these tumors are usually associated with poor prognosis.

  6. Contrastive Analysis of Two Sisters in Sense and Sensibility Based on“Melancholy Philosophy”

    Institute of Scientific and Technical Information of China (English)

    陈元元

    2014-01-01

    Sense and Sensibility, one of Jane Austen’s masterpieces, has undergone a long time study and the two sisters in the book-Elinor and Marianne have been researched from various kinds of perspectives except“melancholy philosophy”. This pa-per aims to analyze the two sisters in Sense and Sensibility under the guidance of“melancholy philosophy”.

  7. 76 FR 315 - Sisters Ranger District; Deschutes National Forest; Oregon; Popper Vegetation Management Project

    Science.gov (United States)

    2011-01-04

    ... comments-pacificnorthwest-deschutes-sisters@fs.fed.us . Please put ``Popper Vegetation Management Project... effects will take place. The Popper Vegetation Management Project decision and the reasons for the... Forest Service Sisters Ranger District; Deschutes National Forest; Oregon; Popper Vegetation Management...

  8. The role of brothers and sisters in the gender development of preschool children.

    Science.gov (United States)

    Rust, J; Golombok, S; Hines, M; Johnston, K; Golding, J

    2000-12-01

    The study examined whether the sex of older siblings influences the gender role development of younger brothers and sisters of age 3 years. Data on the Pre-School Activities Inventory, a measure of gender role behavior that discriminates within as well as between the sexes, were obtained in a general population study for 527 girls and 582 boys with an older sister, 500 girls and 561 boys with an older brother, and 1665 singleton girls and 1707 singleton boys. It was found that boys with older brothers and girls with older sisters were more sex-typed than same-sex singletons who, in turn, were more sex-typed than children with other-sex siblings. Having an older brother was associated with more masculine and less feminine behavior in both boys and girls, whereas boys with older sisters were more feminine but not less masculine and girls with older sisters were less masculine but not more feminine.

  9. Monitoring the exposure of rats to 2-acetylaminofluorene by the estimation of mutagenic activity in excreta, sister-chromatid exchanges in peripheral blood cells and DNA adducts in peripheral blood, liver and spleen

    NARCIS (Netherlands)

    Willems, M.I.; Raat, W.K.de; Baan, R.A.; Wilmer, J.W.G.M.; Lansbergen, M.J.; Lohman, P.H.M.

    1987-01-01

    The sensitivity of various methods suitable for biomonitoring the exposure to genotoxicants was compared in an animal model. The results were related to the presence of genotoxic effects in the target organ. Groups of male Wistar rats were given one oral dose of 0, 0.1, 1, 10 or 200 mg 2-acetylamino

  10. The geography and ecology of plant speciation: range overlap and niche divergence in sister species.

    Science.gov (United States)

    Anacker, Brian L; Strauss, Sharon Y

    2014-03-07

    A goal of evolutionary biology is to understand the roles of geography and ecology in speciation. The recent shared ancestry of sister species can leave a major imprint on their geographical and ecological attributes, possibly revealing processes involved in speciation. We examined how ecological similarity, range overlap and range asymmetry are related to time since divergence of 71 sister species pairs in the California Floristic Province (CFP). We found that plants exhibit strikingly different age-range correlation patterns from those found for animals; the latter broadly support allopatric speciation as the primary mode of speciation. By contrast, plant sisters in the CFP were sympatric in 80% of cases and range sizes of sisters differed by a mean of 10-fold. Range overlap and range asymmetry were greatest in younger sisters. These results suggest that speciation mechanisms broadly grouped under 'budding' speciation, in which a larger ranged progenitor gives rise to a smaller ranged derivative species, are probably common. The ecological and reproductive similarity of sisters was significantly greater than that of sister-non-sister congeners for every trait assessed. However, shifts in at least one trait were present in 93% of the sister pairs; habitat and soil shifts were especially common. Ecological divergence did not increase with range overlap contrary to expectations under character displacement in sympatry. Our results suggest that vicariant speciation is more ubiquitous in animals than plants, perhaps owing to the sensitivity of plants to fine-scale environmental heterogeneity. Despite high levels of range overlap, ecological shifts in the process of budding speciation may result in low rates of fine-scale spatial co-occurrence. These results have implications for ecological studies of trait evolution and community assembly; despite high levels of sympatry, sister taxa and potentially other close relatives, may be missing from local communities.

  11. Concordance of ulcerative colitis in monozygotic twin sisters

    Institute of Scientific and Technical Information of China (English)

    Madoka Horiya; Masatomo Mori; Satoru Kakizaki; Katsunobu Teshigawara; Yuki Kikuchi; Tetsu Hashida; Yoshio Tomizawa; Tomohiro Iida; Takashige Masuo; Hitoshi Takagi

    2005-01-01

    The etiology of inflammatory bowel disease is multifacto rial and appears to combine both genetic and environmental factors. We experienced here a rare occurrence of woman monozygotic twins with ulcerative colitis (UC). A 45-year-old woman (the elder monozygotic twin) was admitted to our hospital because of bloody diarrhea occurring over 10 times per day, abdominal pain and fever. She was diagnosed as UC at the age of 22, and repeated the relapse and remission. She was diagnosed as relapse of UC and total colitis type. Her younger monozygotic twin sister also suffered from UC at the age of 22. Human leukocyte antigen was examined serologically with DNA type in both patients. DRB1*1502, which was previously shown to be dominant in Japanese patients with UC, was not observed in this case. Although the concordance in monozygotic twin in UC is reported to be 6.3-18.8%, the concordant case like this is relatively rare. We report this rare case of UC and the previously reported cases are also discussed.

  12. The unforgotten sisters female astronomers and scientists before Caroline Herschel

    CERN Document Server

    Bernardi, Gabriella

    2016-01-01

    Taking inspiration from Siv Cedering’s poem in the form of a fictional letter from Caroline Herschel that refers to “my long, lost sisters, forgotten in the books that record our science”, this book tells the lives of twenty-five female scientists, with specific attention to astronomers and mathematicians. Each of the presented biographies is organized as a kind of "personal file" which sets the biographee’s life in its historical context, documents her main works, highlights some curious facts, and records citations about her. The selected figures are among the most representative of this neglected world, including such luminaries as Hypatia of Alexandra, Hildegard of Bingen, Elisabetha Hevelius, and Maria Gaetana Agnesi. They span a period of about 4000 years, from En HeduAnna, the Akkadian princess, who was one of the first recognized female astronomers, to the dawn of the era of modern astronomy with Caroline Herschel and Mary Somerville. The book will be of interest to all who wish to learn more ...

  13. The bacterial nucleoid: nature, dynamics and sister segregation.

    Science.gov (United States)

    Kleckner, Nancy; Fisher, Jay K; Stouf, Mathieu; White, Martin A; Bates, David; Witz, Guillaume

    2014-12-01

    Recent studies reveal that the bacterial nucleoid has a defined, self-adherent shape and an underlying longitudinal organization and comprises a viscoelastic matrix. Within this shape, mobility is enhanced by ATP-dependent processes and individual loci can undergo ballistic off-equilibrium movements. In Escherichia coli, two global dynamic nucleoid behaviors emerge pointing to nucleoid-wide accumulation and relief of internal stress. Sister segregation begins with local splitting of individual loci, which is delayed at origin, terminus and specialized interstitial snap regions. Globally, as studied in several systems, segregation is a multi-step process in which internal nucleoid state plays critical roles that involve both compaction and expansion. The origin and terminus regions undergo specialized programs partially driven by complex ATP burning mechanisms such as a ParAB Brownian ratchet and a septum-associated FtsK motor. These recent findings reveal strong, direct parallels among events in different systems and between bacterial nucleoids and mammalian chromosomes with respect to physical properties, internal organization and dynamic behaviors.

  14. Benign multicystic mesothelioma: a case report of three sisters

    Directory of Open Access Journals (Sweden)

    Thomas Rutherford

    2009-12-01

    Full Text Available Benign multicystic mesothelioma (BMCM is a rare tumor of the abdomen-peritoneum of unknown etiology. This benign tumor was initially described by Plaut in 1928 when he observed loose cysts in the pelvis during a surgery for a uterine leiomyoma.2 The mesothelial origin was later confirmed by electron micro-scopy by Mennemeyer and Smith in 1979.3 To date, there are approximately 140 cases of BMCM reported in the literature.4 This disease primarily occurs in pre-menopausal women and is associated with a history of pelvic inflammatory disease, prior abdominal surgery, and endometriosis.4,5 The pathogenesis of this disease remains controversial, with possible etiologies including a neoplastic versus a reactive process.5 In the literature, a few case reports discuss a possible genetic or familial association with BMCM.6 Specifically, one report describes a man with familial Mediterranean fever who developed BMCM. Although familial Mediter-ranean fever is associated with malignant mesothelioma, he had only BMCM, and did not suffer from malignant mesothelioma.6 A genetic evaluation and chromosomal analysis were not able to identify a specific genetic cause of the family’s pattern of disease. This case report describes two female siblings diagnosed with BMCM. In addition, a third sister also had findings consistent with BMCM, however, the discrete histological diagnosis was never confirmed.

  15. Chloroplast phylogenomics indicates that Ginkgo biloba is sister to cycads.

    Science.gov (United States)

    Wu, Chung-Shien; Chaw, Shu-Miaw; Huang, Ya-Yi

    2013-01-01

    Molecular phylogenetic studies have not yet reached a consensus on the placement of Ginkgoales, which is represented by the only living species, Ginkgo biloba (common name: ginkgo). At least six discrepant placements of ginkgo have been proposed. This study aimed to use the chloroplast phylogenomic approach to examine possible factors that lead to such disagreeing placements. We found the sequence types used in the analyses as the most critical factor in the conflicting placements of ginkgo. In addition, the placement of ginkgo varied in the trees inferred from nucleotide (NU) sequences, which notably depended on breadth of taxon sampling, tree-building methods, codon positions, positions of Gnetopsida (common name: gnetophytes), and including or excluding gnetophytes in data sets. In contrast, the trees inferred from amino acid (AA) sequences congruently supported the monophyly of a ginkgo and Cycadales (common name: cycads) clade, regardless of which factors were examined. Our site-stripping analysis further revealed that the high substitution saturation of NU sequences mainly derived from the third codon positions and contributed to the variable placements of ginkgo. In summary, the factors we surveyed did not affect results inferred from analyses of AA sequences. Congruent topologies in our AA trees give more confidence in supporting the ginkgo-cycad sister-group hypothesis.

  16. Narrative research on mental health recovery: two sister paradigms.

    Science.gov (United States)

    Spector-Mersel, Gabriela; Knaifel, Evgeny

    2017-06-24

    Despite the breadth of narrative studies on individuals with severe mental illness, the suitability of narrative inquiry to exploring mental health recovery (MHR) has not been examined. (1) Examining the appropriateness of narrative inquiry to studying MHR; (2) assessing the extent to which narrative studies on MHR conform to the unique features of narrative research, as a distinctive form of qualitative inquiry. Review of empirical, theoretical and methodological literature on recovery and narrative inquiry. Considering the perspectives of recovery and narrative as paradigms, the similarity between their ontology and epistemology is shown, evident in 10 common emphases: meaning, identity, change and development, agency, holism, culture, uniqueness, context, language and giving voice. The resemblance between these "sister" paradigms makes narrative methodology especially fruitful for accessing the experiences of individuals in recovery. Reviewing narrative studies on MHR suggests that, currently, narrative research's uniqueness, centered on the holistic principle, is blurred on the philosophical, methodological and textual levels. Well-established narrative research has major implications for practice and policy in recovery-oriented mental health care. The narrative inquiry paradigm offers a possible path to enhancing the distinctive virtues of this research, realizing its potential in understanding and promoting MHR.

  17. Competitive avoidance not edaphic specialization drives vertical niche partitioning among sister species of ectomycorrhizal fungi

    National Research Council Canada - National Science Library

    Mujic, Alija B; Durall, Daniel M; Spatafora, Joseph W; Kennedy, Peter G

    2016-01-01

    .... In three bioassay experiments, we tested the role of vertical soil heterogeneity in determining the distributions and competitive outcomes of the EM sister species Rhizopogon vinicolor and Rhizopogon vesiculosus...

  18. Extensive range overlap between heliconiine sister species: evidence for sympatric speciation in butterflies?

    National Research Council Canada - National Science Library

    Rosser, Neil; Kozak, Krzysztof M; Phillimore, Albert B; Mallet, James

    2015-01-01

    .... We here quantify geographic overlap of sister species of heliconiine butterflies, and use age-range correlations and spatial simulations of the geography of speciation to infer the frequency of sympatric speciation...

  19. Chromosomal differentiation and speciation in sister-species of Grammatidae (Perciformes) from the Western Atlantic

    National Research Council Canada - National Science Library

    Molina, Wagner Franco; da Costa, Gideão Wagner Werneck Felix; de Bello Cioffi, Marcelo; Bertollo, Luiz Antonio Carlos

    2012-01-01

    ... brasiliensis, endemic in Brazil, and its Caribbean counterpart Gramma loreto. Morphological and molecular studies have helped establish evolutionary patterns that sister-species of these two marine habitats are subjected...

  20. West Sister Island National Wildlife Refuge Wilderness Character Monitoring Back-end Database

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is the back-end data file for the West Sister Island Wilderness Character Monitoring Application. User interface and lookup databases are required for use (see...

  1. 2 SISTERS WITH MENTAL-RETARDATION, CATARACT, ATAXIA, PROGRESSIVE HEARING-LOSS, AND POLYNEUROPATHY

    NARCIS (Netherlands)

    BEGEER, JH; SCHOLTE, FA; VANESSEN, AJ

    1991-01-01

    Two sisters are described with a disorder characterised by mental retardation, congenital cataract, progressive spinocerebellar ataxia, sensorineural deafness, and signs of peripheral neuropathy. Progressive hearing loss, ataxia, and polyneuropathy became evident in the third decade. The differentia

  2. 2 SISTERS WITH MENTAL-RETARDATION, CATARACT, ATAXIA, PROGRESSIVE HEARING-LOSS, AND POLYNEUROPATHY

    NARCIS (Netherlands)

    BEGEER, JH; SCHOLTE, FA; VANESSEN, AJ

    1991-01-01

    Two sisters are described with a disorder characterised by mental retardation, congenital cataract, progressive spinocerebellar ataxia, sensorineural deafness, and signs of peripheral neuropathy. Progressive hearing loss, ataxia, and polyneuropathy became evident in the third decade. The

  3. Psychopathology, childhood trauma, and personality traits in patients with borderline personality disorder and their sisters.

    Science.gov (United States)

    Laporte, Lise; Paris, Joel; Guttman, Herta; Russell, Jennifer

    2011-08-01

    The aim of this study was to document and compare adverse childhood experiences, and personality profiles in women with borderline personality disorder (BPD) and their sisters, and to determine how these factors impact current psychopathology. Fifty-six patients with BPD and their sisters were compared on measures assessing psychopathology, personality traits, and childhood adversities. Most sisters showed little evidence of psychopathology. Both groups reported dysfunctional parent-child relationships and a high prevalence of childhood trauma. Subjects with BPD reported experiencing more emotional abuse and intrafamilial sexual abuse, but more similarities than differences between probands and sisters were found. In multilevel analyses, personality traits of affective instability and impulsivity predicted DIB-R scores and SCL-90-R scores, above and beyond trauma. There were few relationships between childhood adversities and other measures of psychopathology. Sensitivity to adverse experiences, as reflected in the development of psychopathology, appears to be influenced by personality trait profiles.

  4. [The work of Moscow communities of Sisters of Charity in own medical institutions].

    Science.gov (United States)

    Zorin, K V

    2011-01-01

    The article analyses the medical activities of Moscow communities of Sisters of Charity in curative and educational institutions organized by the communities themselves. The social ministration of communities on the territory of Moscow is considered.

  5. Endovascular Repair of Internal Mammary Artery Aneurysms in Two Sisters with SMAD3 Mutation.

    Science.gov (United States)

    Nevidomskyte, Daiva; Shalhub, Sherene; Aldea, Gabriel S; Byers, Peter H; Schwarze, Ulrike; Murray, Mitzi L; Starnes, Benjamin

    2017-03-07

    True aneurysms of the internal mammary artery are rare and have been described in association with vasculitis or connective tissue disorders. Herein we describe two cases of familial internal mammary artery aneurysms in two sisters with SMAD3 mutation. The older sister presented at the age of 54 with an incidental diagnosis of a multilobed right internal mammary artery aneurysm (IMA) and the younger sister presented several years earlier with a ruptured left IMA aneurysm at the age of 49. Both sisters had Debakey type I aortic dissections prior to the IMA aneurysm presentation. To our knowledge this is the first time IMA aneurysms has been described in siblings with SMAD3 mutation. In our experience endovascular repair is a feasible and safe treatment option. An assessment of the entire arterial tree is recommended in patients diagnosed with SMAD3 mutations.

  6. Genomic data do not support comb jellies as the sister group to all other animals.

    Science.gov (United States)

    Pisani, Davide; Pett, Walker; Dohrmann, Martin; Feuda, Roberto; Rota-Stabelli, Omar; Philippe, Hervé; Lartillot, Nicolas; Wörheide, Gert

    2015-12-15

    Understanding how complex traits, such as epithelia, nervous systems, muscles, or guts, originated depends on a well-supported hypothesis about the phylogenetic relationships among major animal lineages. Traditionally, sponges (Porifera) have been interpreted as the sister group to the remaining animals, a hypothesis consistent with the conventional view that the last common animal ancestor was relatively simple and more complex body plans arose later in evolution. However, this premise has recently been challenged by analyses of the genomes of comb jellies (Ctenophora), which, instead, found ctenophores as the sister group to the remaining animals (the "Ctenophora-sister" hypothesis). Because ctenophores are morphologically complex predators with true epithelia, nervous systems, muscles, and guts, this scenario implies these traits were either present in the last common ancestor of all animals and were lost secondarily in sponges and placozoans (Trichoplax) or, alternatively, evolved convergently in comb jellies. Here, we analyze representative datasets from recent studies supporting Ctenophora-sister, including genome-scale alignments of concatenated protein sequences, as well as a genomic gene content dataset. We found no support for Ctenophora-sister and conclude it is an artifact resulting from inadequate methodology, especially the use of simplistic evolutionary models and inappropriate choice of species to root the metazoan tree. Our results reinforce a traditional scenario for the evolution of complexity in animals, and indicate that inferences about the evolution of Metazoa based on the Ctenophora-sister hypothesis are not supported by the currently available data.

  7. Ecological divergence and speciation between lemur (Eulemur) sister species in Madagascar.

    Science.gov (United States)

    Blair, M E; Sterling, E J; Dusch, M; Raxworthy, C J; Pearson, R G

    2013-08-01

    Understanding ecological niche evolution over evolutionary timescales is crucial to elucidating the biogeographic history of organisms. Here, we used, for the first time, climate-based ecological niche models (ENMs) to test hypotheses about ecological divergence and speciation processes between sister species pairs of lemurs (genus Eulemur) in Madagascar. We produced ENMs for eight species, all of which had significant validation support. Among the four sister species pairs, we found nonequivalent niches between sisters, varying degrees of niche overlap in ecological and geographic space, and support for multiple divergence processes. Specifically, three sister-pair comparisons supported the null model that niches are no more divergent than the available background region. These findings are consistent with an allopatric speciation model, and for two sister pairs (E. collaris-E. cinereiceps and E. rufus-E. rufifrons), a riverine barrier has been previously proposed for driving allopatric speciation. However, for the fourth sister pair E. flavifrons-E. macaco, we found support for significant niche divergence, and consistent with their parapatric distribution on an ecotone and the lack of obvious geographic barriers, these findings most strongly support a parapatric model of speciation. These analyses thus suggest that various speciation processes have led to diversification among closely related Eulemur species.

  8. IVF for premature ovarian failure: first reported births using oocytes donated from a twin sister

    Directory of Open Access Journals (Sweden)

    Sills Eric

    2010-03-01

    Full Text Available Abstract Background Premature ovarian failure (POF remains a clinically challenging entity because in vitro fertilisation (IVF with donor oocytes is currently the only treatment known to be effective. Methods A 33 year-old nulligravid patient with a normal karyotype was diagnosed with POF; she had a history of failed fertility treatments and had an elevated serum FSH (42 mIU/ml. Oocytes donated by her dizygotic twin sister were used for IVF. The donor had already completed a successful pregnancy herself and subsequently produced a total of 10 oocytes after a combined FSH/LH superovulation regime. These eggs were fertilised with sperm from the recipient's husband via intracytoplasmic injection and two fresh embryos were transferred to the recipient on day three. Results A healthy twin pregnancy resulted from IVF; two boys were delivered by caesarean section at 39 weeks' gestation. Additionally, four embryos were cryopreserved for the recipient's future use. The sister-donor achieved another natural pregnancy six months after oocyte retrieval, resulting in a healthy singleton delivery. Conclusion POF is believed to affect approximately 1% of reproductive age females, and POF patients with a sister who can be an oocyte donor for IVF are rare. Most such IVF patients will conceive from treatment using oocytes from an anonymous oocyte donor. This is the first report of births following sister-donor oocyte IVF in Ireland. Indeed, while sister-donor IVF has been successfully undertaken by IVF units elsewhere, this is the only known case where oocyte donation involved twin sisters. As with all types of donor gamete therapy, pre-treatment counselling is important in the circumstance of sister oocyte donation.

  9. IVF for premature ovarian failure: first reported births using oocytes donated from a twin sister.

    LENUS (Irish Health Repository)

    Sills, Eric Scott

    2010-01-01

    BACKGROUND: Premature ovarian failure (POF) remains a clinically challenging entity because in vitro fertilisation (IVF) with donor oocytes is currently the only treatment known to be effective. METHODS: A 33 year-old nulligravid patient with a normal karyotype was diagnosed with POF; she had a history of failed fertility treatments and had an elevated serum FSH (42 mIU\\/ml). Oocytes donated by her dizygotic twin sister were used for IVF. The donor had already completed a successful pregnancy herself and subsequently produced a total of 10 oocytes after a combined FSH\\/LH superovulation regime. These eggs were fertilised with sperm from the recipient\\'s husband via intracytoplasmic injection and two fresh embryos were transferred to the recipient on day three. RESULTS: A healthy twin pregnancy resulted from IVF; two boys were delivered by caesarean section at 39 weeks\\' gestation. Additionally, four embryos were cryopreserved for the recipient\\'s future use. The sister-donor achieved another natural pregnancy six months after oocyte retrieval, resulting in a healthy singleton delivery. CONCLUSION: POF is believed to affect approximately 1% of reproductive age females, and POF patients with a sister who can be an oocyte donor for IVF are rare. Most such IVF patients will conceive from treatment using oocytes from an anonymous oocyte donor. This is the first report of births following sister-donor oocyte IVF in Ireland. Indeed, while sister-donor IVF has been successfully undertaken by IVF units elsewhere, this is the only known case where oocyte donation involved twin sisters. As with all types of donor gamete therapy, pre-treatment counselling is important in the circumstance of sister oocyte donation.

  10. Identifying possible sister groups of Cryptocercidae+Isoptera: a combined molecular and morphological phylogeny of Dictyoptera.

    Science.gov (United States)

    Djernæs, Marie; Klass, Klaus-Dieter; Eggleton, Paul

    2015-03-01

    Termites (Isoptera) offer an alternative model for the development of eusociality which is not dependent on a high degree of relatedness as found between sisters in hymenopterans (bees, wasps, ants). Recent phylogenetic studies have established that termites belong within the cockroaches as sister to the subsocial Cryptocercidae. Cryptocercidae shares several important traits with termites, thus we need to understand the phylogenetic position of Cryptocercidae+Isoptera to determine how these traits evolved. However, placement of Cryptocercidae+Isoptera is still uncertain. We used both molecular (12S, 16S, COII, 18S, 28S, H3) and morphological characters to reconstruct the phylogeny of Dictyoptera. We included all previously suggested sister groups of Cryptocercidae+Isoptera as well as taxa which might represent additional major cockroach lineages. We used Bayes factors to test different sister groups for Cryptocercidae+Isoptera and assessed character support for the consensus tree based on morphological characters and COII amino acid data. We used the molecular data and fossil calibration to estimate divergence times. We found the most likely sister groups of Cryptocercidae+Isoptera to be Tryonicidae, Anaplecta or Tryonicidae+Anaplecta. Anaplecta has never previously been suggested as sister group or even close to Cryptocercidae+Isoptera, but was formerly placed in Blaberoidea as sister to the remaining taxa. Topological tests firmly supported our new placement of Anaplecta. We discuss the morphological characters (e.g. retractable genitalic hook) that have contributed to the previous placement of Anaplecta in Blaberoidea as well as the factors that might have contributed to a parallel development of genitalic features in Anaplecta and Blaberoidea. Cryptocercidae+Isoptera is placed in a clade with Tryonicidae, Anaplecta and possibly Lamproblattidae. Based on this, we suggest that wood-feeding, and the resultant need to conserve nitrogen, may have been an important

  11. Digital Data for Volcano Hazards of the Three Sisters Region, Oregon

    Science.gov (United States)

    Schilling, S.P.; Doelger, S.; Scott, W.E.; Iverson, R.M.

    2008-01-01

    Three Sisters is one of three active volcanic centers that lie close to rapidly growing communities and resort areas in Central Oregon. The major composite volcanoes of this area are clustered near the center of the region and include South Sister, Middle Sister, and Broken Top. Additionally, hundreds of mafic volcanoes are scattered throughout the Three Sisters area. These range from small cinder cones to large shield volcanoes like North Sister and Belknap Crater. Hazardous events include landslides from the steep flanks of large volcanoes and floods, which need not be triggered by eruptions, as well as eruption-triggered events such as fallout of tephra (volcanic ash) and lava flows. A proximal hazard zone roughly 20 kilometers (12 miles) in diameter surrounding the Three Sisters and Broken Top could be affected within minutes of the onset of an eruption or large landslide. Distal hazard zones that follow river valleys downstream from the Three Sisters and Broken Top could be inundated by lahars (rapid flows of water-laden rock and mud) generated either by melting of snow and ice during eruptions or by large landslides. Slow-moving lava flows could issue from new mafic volcanoes almost anywhere within the region. Fallout of tephra from eruption clouds can affect areas hundreds of kilometers (miles) downwind, so eruptions at volcanoes elsewhere in the Cascade Range also contribute to volcano hazards in Central Oregon. Scientists at the Cascades Volcano Observatory created a geographic information system (GIS) data set which depicts proximal and distal lahar hazard zones as well as a regional lava flow hazard zone for Three Sisters (USGS Open-File Report 99-437, Scott and others, 1999). The various distal lahar zones were constructed from LaharZ software using 20, 100, and 500 million cubic meter input flow volumes. Additionally, scientists used the depositional history of past events in the Three Sisters Region as well as experience and judgment derived from the

  12. The management of professionals: the preferences of hospital sisters and charge nurses.

    Science.gov (United States)

    Foster, D

    1995-05-01

    This analysis of the preferences of how sisters and charge nurses are managed is the result of a two centre descriptive study using theoretical models of professionalism, developing preferences and exercising situational leadership. It was conducted to determine if the management structure preferred by sisters and charge nurses, in a general acute hospital setting, supported the professionalism of nursing. The outcomes were intended to help develop a strategic plan for the future of nursing and the management of nurses. The research instruments were a self-completed questionnaire (19 were returned, a response rate of 31.1%) and four semi-structured interviews. The findings disclosed some dissatisfaction with the present management arrangements. The sisters and charge nurses felt that their priorities for practice and professional issues were better supported by clinically involved, ward-based senior nurses than by unit-based senior nurses with a general management function. However, sisters' and charge nurses' discussions with ward-based senior nurses were apparently less effective than discussions in peer groups which led to influential collegial autonomy. This preferred management style can be supported by the use of situational leadership theory which would enhance collegial autonomy and professional satisfaction. Recognition of the sisters and charge nurses preferences and adjustment of their management would therefore enable them to participate effectively in organizational decision-making.

  13. Neuropsychological profiles of three sisters homozygous for the fragile X premutation

    Energy Technology Data Exchange (ETDEWEB)

    Mazzocco, M.M.M. [Johns Hopkins School of Medicine, Baltimore, MD (United States); Holden, J.J.A. [Ongwanada Resource Centre, Kingston, Ontario (Canada)

    1996-08-09

    Fragile X syndrome (fraX) is associated with an amplification of a CGG repeat within the fraX mental retardation (FMR-1) gene. We describe an exceptional family in which 3 adult sisters are homozygous for the FMR-1 premutation. Each sister inherited 2 premutation alleles (ca. 80 CGG repeats) from their biologically unrelated parents. The 3 sisters were administered measures of executive function, visual spatial, memory, and verbal skills. Deficiencies in the first 2 of these domains have been reported among females with the full mutation. The sisters` performances were compared with available normative data and with published group means for females affected by fraX. These women did not appear to have verbal or memory difficulties. None of the women demonstrated a global executive function deficit, and none had global deficits in spatial ability. The profiles of these sisters are consistent with reports that the fragile X premutation does not affect cognitive performance. 31 refs., 1 fig., 4 tabs.

  14. Investigating the etiology of multiple tooth agenesis in three sisters with severe oligodontia.

    Science.gov (United States)

    Swinnen, S; Bailleul-Forestier, I; Arte, S; Nieminen, P; Devriendt, K; Carels, C

    2008-02-01

    To describe the dentofacial phenotypes of three sisters with severe non-syndromic oligodontia, to report on the mutation analysis in three genes, previously shown to cause various phenotypes of non-syndromic oligodontia and in two other suspected genes. Based on the phenotypes in the pedigree of this family, the different possible patterns of transmission are discussed. Anamnestic data and a panoramic radiograph were taken to study the phenotype of the three sisters and their first-degree relatives. Blood samples were also taken to obtain their karyotypes and DNA samples. Mutational screening was performed for the MSX1, PAX9, AXIN2, DLX1 and DLX2 genes. The probands' pedigree showed evidence for a recessive or multifactorial inheritance pattern. Normal chromosomal karyotypes were found and - despite the severe oligodontia present in all three sisters - no mutation appeared to be present in the five genes studied so far in these patients. In the three sisters reported, their common oligodontia phenotype is not caused by mutations in the coding regions of MSX1, PAX9, AXIN2, DLX1 or DLX2 genes, but genetic factors most probably play a role as all three sisters were affected. Environmental and epigenetic factors as well as genes regulating odontogenesis need further in vivo and in vitro investigation to explain the phenotypic heterogeneity and to increase our understanding of the odontogenic processes.

  15. Yeast Interacting Proteins Database: YCL029C, YER016W [Yeast Interacting Proteins Database

    Lifescience Database Archive (English)

    Full Text Available rotubules and kinetochore, involved in sister chromatid separation; essential in polyploid cells but not in ...le-associated protein, component of the interface between microtubules and kinetochore, involved in sister chromatid separation

  16. Yeast Interacting Proteins Database: YDL089W, YML008C [Yeast Interacting Proteins Database

    Lifescience Database Archive (English)

    Full Text Available rDNA repeat stability; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein...peat stability; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein localiz

  17. Sequence Classification: 893950 [

    Lifescience Database Archive (English)

    Full Text Available associated protein, required for sister chromatid cohesion; interacts with DNA polymerase alpha (Pol1p) and ...may link DNA synthesis to sister chromatid cohesion; Ctf4p || http://www.ncbi.nlm.nih.gov/protein/6325393 ...

  18. Sequence Classification: 893838 [

    Lifescience Database Archive (English)

    Full Text Available sion complex; maintains cohesion between sister chromatids during meiosis I; maintains cohesion...TMB Non-TMH TMB TMB TMB TMB >gi|6325264|ref|NP_015332.1| Meiosis-specific component of sister chromatid cohe

  19. Sexual and physical abuse: a comparison between lesbians and their heterosexual sisters.

    Science.gov (United States)

    Stoddard, Joel P; Dibble, Suzanne L; Fineman, Norman

    2009-01-01

    The purpose of this study was to investigate similarities and differences in the incidence and patterns of abuse experienced by lesbians and their heterosexual sisters. In a matched sample of 324 lesbian/heterosexual sister pairs, the lesbians reported a greater incidence than their sisters of childhood physical and sexual abuse, as well as adult sexual abuse. Both groups identified male relatives as the most common perpetrator of both childhood physical and sexual abuse. Male relatives were most commonly identified as perpetrators of adult physical abuse and male strangers were most commonly identified as adult sexual abusers. Our results demonstrate that both sexual and physical abuse are common experiences for lesbian and heterosexual women; however, since the context of these experiences is different, each group will have special needs for services and treatment.

  20. A Feminist Reading of Sister Carrie: Carrie——the Aspiring Cinderella

    Institute of Scientific and Technical Information of China (English)

    殷娟

    2008-01-01

    Like Cinderella in the fairy tale Cinderella, Carrie is beautiful, innocent and poor. But unlike the traditional Cinderella who mindlessly waits around for a handsome prince to come to her rescue, Carrie, the aspiring Cinderella, resolvedly leaves the men she ever depended on and eventually becomes a successful actress. Sister Carrie, the most impressive heroine of Theodore Dreiser, is a contradictory character. Some accuse her of realizing her ambition with immoral means. However, some others take sympathy with her courage, determination, and aspiration. By analyzing the most distinguished quality of Sister Carrie - her aspiration, this essay is to illustrate from the perspective of feminism that women are not limited by their sex. Ignoring her own sex as well as the conventional attitude toward women in a male-dominated society, sister Carrie, full of aspiration, takes an active pan in creating and determining her own lives and her own futures..

  1. Causes of the Disillusionment of Sister Carrie’s American Dream

    Institute of Scientific and Technical Information of China (English)

    谭佳

    2013-01-01

    Theodore Dreiser’s novel Sister Carrie is the representative of studying the disillusionment of the American Dream. Since the publication of Sister Carrie,there have been many critics who commented on this work, and its main character Sister Carrie is a controversial person. Dreiser was criticized by critics and readers because he didn ’t give any comment on her degener-ation. This thesis tries to analyze the causes of this tragedy.In the end, the paper draws the conclusion:the American Dream looks beautiful, but to some extent it is not reliable, just like the foam of soap. It only gives people an illusion. So Carrie ’s tragedy is in-evitable.

  2. Osteological evidence for sister group relationship between pseudo-toothed birds (Aves: Odontopterygiformes) and waterfowls (Anseriformes)

    Science.gov (United States)

    Bourdon, Estelle

    2005-12-01

    The phylogenetic affinities of the extinct pseudo-toothed birds have remained controversial. Some authors noted that they resemble both pelicans and allies (Pelecaniformes) and tube-nosed birds (Procellariiformes), but assigned them to a distinct taxon, the Odontopterygiformes. In most recent studies, the pseudo-toothed birds are referred to the family Pelagornithidae inside the Pelecaniformes. Here, I perform a cladistic analysis with five taxa of the pseudo-toothed birds including two undescribed new species from the Early Tertiary of Morocco. The present hypothesis strongly supports a sister group relationship of pseudo-toothed birds (Odontopterygiformes) and waterfowls (Anseriformes). The Odontoanserae (Odontopterygiformes plus Anseriformes) are the sister group of Neoaves. The placement of the landfowls (Galliformes) as the sister taxon of all other neognathous birds does not support the consensus view that the Galloanserae (Galliformes plus Anseriformes) are monophyletic.

  3. Protein (Viridiplantae): 356522276 [PGDBj - Ortholog DB

    Lifescience Database Archive (English)

    Full Text Available 3847:837 PREDICTED: sister chromatid cohesion protein PDS5-like Glycine max MYFSAAYEFWKLELLLSSLDQEPTKPIQESLV...PAMKALISDELLRHTDGDVKISVTSCINEITRITAPDVPYDDEQMKEIFKLTVASFEKLSHISGRGYEKALTILDNANKVRLCLVMLDLECNDLVIEMFQHFLRYIRHPPIAKVYVRKIGKGSRTLGFTWALRKIVEITISDI ...

  4. Ukrainian and European Baroque in the Context of “Sister Arts” Idea

    Directory of Open Access Journals (Sweden)

    Olga Shikirinskaya

    2015-08-01

    Full Text Available The article deals with the “Sister Arts” tradition as the interrelationship of various art forms (poetry, fiction, painting, theatre, music etc. relative to the Baroque period. “Sister Arts” criticism, based on E.G. Lessing essay “Laocoön…” uses the inter-art analogies to appreciate the importance of literature in the Arts, as well as to comprehend aspects of the modern approach to the synthesis of the arts. The article presents the aesthetic concept of Baroque art and its realization in architecture, sculpture, decorative and applied arts, music and literature on the background of the European and Ukrainian cultural tradition.

  5. On the major Characteristics of Writing in Dreiser’s Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    张含

    2014-01-01

    Dreiser’s Sister Carrie has been controverted for a long time. It is still consummate today and as alive and valid as when it was written. First, the description of the psychology plays an important role in revealing the personalities of the major characters and deepens the theme. The second is Dreiser’s usage of comparison. Finally Dreiser uses the method of realism like Balzac. Sister Carrie is the exact reflection and the mirror of the society. Its special characteristics and the realistic writing style start a new field in American literature.

  6. Synergistic convergence and split pons in horizontal gaze palsy and progressive scoliosis in two sisters

    Directory of Open Access Journals (Sweden)

    Jain Nitin

    2011-01-01

    Full Text Available Synergistic convergence is an ocular motor anomaly where on attempted abduction or on attempted horizontal gaze, both the eyes converge. It has been related to peripheral causes such as congenital fibrosis of extraocular muscles (CFEOM, congenital cranial dysinnervation syndrome, ocular misinnervation or rarely central causes like horizontal gaze palsy with progressive scoliosis, brain stem dysplasia. We hereby report the occurrence of synergistic convergence in two sisters. Both of them also had kyphoscoliosis. Magnetic resonance imaging (MRI brain and spine in both the patients showed signs of brain stem dysplasia (split pons sign differing in degree (younger sister had more marked changes.

  7. The Influence of Sister Carrie’s Female Consciousness on Chinese Women

    Institute of Scientific and Technical Information of China (English)

    张佳

    2015-01-01

    Since Sister Carrie’s publication, it has attracted various criticism and comments on Carrie. There are many studies to explore Sister Carrie from various perspectives. The influence of Carrie’s female consciousness on Chinese women is the focus to discuss in the thesis. From Carrie, we realize Carrie is brave and successful in that “survival for the fittest” world. We cannot deny that Carrie is of great importance in present China in enlightening people’s value and women’s social position.

  8. Sister Mary Joseph Nodules on 99mTc HYNIC-TOC scintigraphy in patients with neuroendocrine tumors.

    Science.gov (United States)

    Jing, Hongli; Zhang, Yingqiang; Li, Fang

    2015-02-01

    A Sister Mary Joseph nodule represents an umbilical metastasis, which is more commonly caused by a primary malignancy in gastrointestinal tract or from reproductive system. We report Sister Mary Joseph nodules caused by neuroendocrine tumor and revealed on Tc HYNIC-TOC scintigraphy.

  9. 77 FR 66851 - Submission for OMB Review; Comment Request The Sister Study: A Prospective Study of the Genetic...

    Science.gov (United States)

    2012-11-07

    ...: A Prospective Study of the Genetic and Environmental Risk Factors for Breast Cancer SUMMARY: Under... Collection: Title: The Sister Study: A Prospective Study of the Genetic and Environmental Risk Factors for...: This is to continue the Phase II follow-up of the Sister Study -- a study of genetic and...

  10. 77 FR 48993 - Proposed Collection; Comment Request; The Sister Study: A Prospective Study of the Genetic and...

    Science.gov (United States)

    2012-08-15

    ... Proposed Collection; Comment Request; The Sister Study: A Prospective Study of the Genetic and... Prospective Study of the Genetic and Environmental Risk Factors for Breast Cancer. Type of Information...-up of the Sister Study--a study of genetic and environmental risk factors for the development...

  11. Empirical Psycho-Aesthetics and Her Sisters: Substantive and Methodological Issues--Part II

    Science.gov (United States)

    Konecni, Vladimir J.

    2013-01-01

    Empirical psycho-aesthetics is approached in this two-part article from two directions. Part I, which appeared in the Winter 2012 issue of "JAE," addressed definitional and organizational issues, including the field's origins, its relation to "sister" disciplines (experimental philosophy, cognitive neuroscience of art, and neuroaesthetics), and…

  12. Study on Sister Carrie’s Purity from the Society and Her Nature

    Institute of Scientific and Technical Information of China (English)

    Wu Yu-xia; Dong Ting-jian

    2014-01-01

    Dreiser’s Sister Carrie often has negative comments, while her pursuit of happiness and ideal with pure faith under the dark social environment deserve study. Her characters shown in the struggle of life and her love affairs has been stated, which proves Carrie’purity in chasing dreams in the dirty society.

  13. Study on Sister Carrie’s Purity from the Society and Her Nature

    Institute of Scientific and Technical Information of China (English)

    Wu; Yu-xia; Dong; Ting-jian

    2014-01-01

    Dreiser’s Sister Carrie often has negative comments,while her pursuit of happiness and ideal with pure faith under the dark social environment deserve study.Her characters shown in the struggle of life and her love affairs has been stated,which proves Carrie’purity in chasing dreams in the dirty society.

  14. Brother-Sister Incest: Data from Anonymous Computer-Assisted Self Interviews

    Science.gov (United States)

    Stroebel, Sandra S.; O'Keefe, Stephen L.; Beard, Keith W.; Kuo, Shih-Ya; Swindell, Samuel; Stroupe, Walter

    2013-01-01

    Retrospective data were entered anonymously by 1,521 adult women using computer-assisted self interview. Forty were classified as victims of brother-sister incest, 19 were classified as victims of father-daughter incest, and 232 were classified as victims of sexual abuse by an adult other than their father before reaching 18 years of age. The…

  15. PERRAULT'S SYNDROME: A CLINICAL AND GENETIC INVESTIGATION OF THREE SISTERS

    Directory of Open Access Journals (Sweden)

    P. Mehdipour

    1999-07-01

    Full Text Available Perrault's syndrome (P.S. is rare. The combination of gonadal dysgenesis and hearing loss was accompanied by 46,XXkaryotype in three sisters with parental consanguineous marriage. Genetic investigation revealed normal female karyotype, positive liarr and negative fluorescence iPj-bodies, which was confirmed by molecular study on the basis of fluorescence in situ hybridization (PISH, with application of Keen probe, showing the presence of two signals in 95% of the cells of these 3 Iranian sisters. The pedigree showed parental consanguinity (first cousin with an autosomal mode of inheritance for both Perrault's syndrome and hearing loss. These findings together with normal thyroid function, serum prolactin, high level of .serum gonadotropins is similar to the menopausal period in all 3 sisters. Estrogen and progesterone were recommended for all 3 sisters. This combined therapy led to mensturation and after a few montfis their breasts were normally developed. Tor further management cochlear implantation, speech therapy and training courses were suggested in order to improve hearing and intellectual abilities.

  16. Subcortical laminar heterotopia in two sisters and their mother : MRI, clinical findings and pathogenesis

    NARCIS (Netherlands)

    van der Valk, PHM; Snoeck, [No Value; Meiners, LC; des Portes, [No Value; Chelly, J; Pinard, JM; Ippel, PF; van Nieuwenhuizen, O

    1999-01-01

    MR imaging, clinical data and underlying pathogenesis of subcortical laminar heterotopia (SCLH), also known as band heterotopia, in two sisters and their mother are presented. On MR imaging a different degree of SCLH was found in all three affected family-members. The inversion recovery sequence was

  17. "Brothers and Sisters": A Novel Way to Teach Human Resources Management.

    Science.gov (United States)

    Bumpus, Minnette

    2000-01-01

    The novel "Brothers and Sisters" by Bebe Moore Campbell was used in a management course to explore human resource management issues, concepts, and theories. The course included prereading and postreading surveys, lecture, book review, and examination. Most of the students (92%) felt the novel was an appropriate way to meet course objectives. (SK)

  18. A sister group metabolomic contrast delineates the biochemical regulation underlying desiccation tolerance in Sporobolus stapfianus

    Science.gov (United States)

    Understanding how plant cells tolerate dehydration is a vital prerequisite for developing strategies for improving drought tolerance. The desiccation tolerant grass Sporobolus stapfianus and the desiccation sensitive S. pyramidalis were used to form a sister-group contrast to reveal adaptive metabo...

  19. Three Sisters: Lessons of Traditional Story Honored in Assessment and Accreditation

    Science.gov (United States)

    Chenault, Venida S.

    2008-01-01

    The three sisters story is shared across many tribes. It explains the practice of planting corn, beans, and squash together. The corn stalks provide support for the bean vines; the beans provide nitrogen for the corn; and the squash prevents weed growth between the mounds. Such stories explain not only the science of agricultural methods in tribal…

  20. Analyzing of Sister Carrie's Independence Process from the Perspective of Feminism

    Institute of Scientific and Technical Information of China (English)

    姜新新

    2015-01-01

    "Sister Carrie" is published when the American society is in the transition from traditional industry to modern industry.Modern industrial not only provide opportunity to the development of city,but also offer some employment opportunities to the people,while the survival pressure for living is also increased.People's thought also undergo a tremendous change.They even feel puzzled andconfused.

  1. Food Yields and Nutrient Analyses of the Three Sisters: A Haudenosaunee Cropping System

    Directory of Open Access Journals (Sweden)

    Jane Mt.Pleasant

    2016-11-01

    Full Text Available Scholars have studied The Three Sisters, a traditional cropping system of the Haudenosaunee (Iroquois, from multiple perspectives. However, there is no research examining food yields, defined as the quantities of energy and protein produced per unit land area, from the cropping system within Iroquoia. This article compares food yields and other nutrient contributions from the Three Sisters, comprised of interplanted maize, bean and pumpkin, with monocultures of these same crops. The Three Sisters yields more energy (12.25 x 106 kcal/ha and more protein (349 kg/ha than any of the crop monocultures or mixtures of monocultures planted to the same area. The Three Sisters supplies 13.42 people/ha/yr. with energy and 15.86 people/ha/yr. with protein. Nutrient contents of the crops are further enhanced by nixtamalization, a traditional processing technique where maize is cooked in a high alkaline solution. This process increases calcium, protein quality, and niacin in maize.

  2. Mutant analysis, protein-protein interactions and subcellular localization of the Arabidopsis B sister (ABS) protein.

    Science.gov (United States)

    Kaufmann, Kerstin; Anfang, Nicole; Saedler, Heinz; Theissen, Günter

    2005-09-01

    Recently, close relatives of class B floral homeotic genes, termed B(sister) genes, have been identified in both angiosperms and gymnosperms. In contrast to the B genes themselves, B(sister) genes are exclusively expressed in female reproductive organs, especially in the envelopes or integuments surrounding the ovules. This suggests an important ancient function in ovule or seed development for B(sister) genes, which has been conserved for about 300 million years. However, investigation of the first loss-of-function mutant for a B(sister) gene (ABS/TT16 from Arabidopsis) revealed only a weak phenotype affecting endothelium formation. Here, we present an analysis of two additional mutant alleles, which corroborates this weak phenotype. Transgenic plants that ectopically express ABS show changes in the growth and identity of floral organs, suggesting that ABS can interact with floral homeotic proteins. Yeast-two-hybrid and three-hybrid analyses indicated that ABS can form dimers with SEPALLATA (SEP) floral homeotic proteins and multimeric complexes that also include the AGAMOUS-like proteins SEEDSTICK (STK) or SHATTERPROOF1/2 (SHP1, SHP2). These data suggest that the formation of multimeric transcription factor complexes might be a general phenomenon among MIKC-type MADS-domain proteins in angiosperms. Heterodimerization of ABS with SEP3 was confirmed by gel retardation assays. Fusion proteins tagged with CFP (Cyan Fluorescent Protein) and YFP (Yellow Fluorescent Protein) in Arabidopsis protoplasts showed that ABS is localized in the nucleus. Phylogenetic analysis revealed the presence of a structurally deviant, but closely related, paralogue of ABS in the Arabidopsis genome. Thus the evolutionary developmental genetics of B(sister) genes can probably only be understood as part of a complex and redundant gene network that may govern ovule formation in a conserved manner, which has yet to be fully explored.

  3. Extensive range overlap between heliconiine sister species: evidence for sympatric speciation in butterflies?

    Science.gov (United States)

    Rosser, Neil; Kozak, Krzysztof M; Phillimore, Albert B; Mallet, James

    2015-06-30

    Sympatric speciation is today generally viewed as plausible, and some well-supported examples exist, but its relative contribution to biodiversity remains to be established. We here quantify geographic overlap of sister species of heliconiine butterflies, and use age-range correlations and spatial simulations of the geography of speciation to infer the frequency of sympatric speciation. We also test whether shifts in mimetic wing colour pattern, host plant use and climate niche play a role in speciation, and whether such shifts are associated with sympatry. Approximately a third of all heliconiine sister species pairs exhibit near complete range overlap, and analyses of the observed patterns of range overlap suggest that sympatric speciation contributes 32%-95% of speciation events. Müllerian mimicry colour patterns and host plant choice are highly labile traits that seem to be associated with speciation, but we find no association between shifts in these traits and range overlap. In contrast, climatic niches of sister species are more conserved. Unlike birds and mammals, sister species of heliconiines are often sympatric and our inferences using the most recent comparative methods suggest that sympatric speciation is common. However, if sister species spread rapidly into sympatry (e.g. due to their similar climatic niches), then assumptions underlying our methods would be violated. Furthermore, although we find some evidence for the role of ecology in speciation, ecological shifts did not show the associations with range overlap expected under sympatric speciation. We delimit species of heliconiines in three different ways, based on "strict and " "relaxed" biological species concepts (BSC), as well as on a surrogate for the widely-used "diagnostic" version of the phylogenetic species concept (PSC). We show that one reason why more sympatric speciation is inferred in heliconiines than in birds may be due to a different culture of species delimitation in the two

  4. The use of convent archival records in medical research: the School Sisters of Notre Dame archives and the nun study.

    Science.gov (United States)

    Patzwald, Gari-Anne; Wildt, Sister Carol Marie

    2004-01-01

    The School Sisters of Notre Dame (SSND) archives program in a cooperative system for the arrangement and preservation of the records of the SSND provinces in North America, including records of individual sisters. Archival records include autobiographies, school and college transcripts, employment histories, and family socioeconomic data. The Nun Study, a longitudinal study of Alzheimer's disease and aging in 678 SSND sisters, compares data extracted from these records with data on late-life cognitive and physical function and postmortem brain neuropathology to explore early life factor that may affect late-life cognitive function and longevity.

  5. Self-healing photo-neuropathy and cervical spinal arthrosis in four sisters with brachioradial pruritus

    Directory of Open Access Journals (Sweden)

    Wallengren Joanna

    2009-11-01

    Full Text Available Abstract The cause of brachioradial pruritus (a localized itching on the arms or shoulders is controversial. The role of sun and cervical spine disease has been discussed. This is a report on four sisters suffering from brachioradial pruritus recurring every summer. The sisters spent much time outdoors and exposed themselves extensively to the sun. They also had occupations requiring heavy lifting. Cervical radiographs indicated arthrosis. The density of sensory nerve fibers in the skin biopsies from the itchy skin of the arms, visualized by antibodies against a pan-neuronal marker, protein gene product 9.5, was reduced compared with biopsies from the same skin region during the symptom-free period in the winter. This data exemplifies that brachioradial pruritus is a self healing photoneuropathy occurring in middle aged adults predisposed by cervical arthrosis.

  6. [Egon Erwin Kisch and the Blazek sisters. A contribution to the history of teratology].

    Science.gov (United States)

    Schierhorn, H

    1985-01-01

    A century ago, on April 29th 1885, the "Raving Reporter" Egon Erwin Kisch was born in Prague. On this occasion his news-reporting about the conjoined Bohemian twins Rosa and Josefa Blazek (born 1878) is appreciated and compared respectively contrasted with the observations and papers of contemporary physicians, among them the famous neuropathologist Richard Henneberg from Berlin and the important gynaecologists Breisky and Pitha from Prague and Schauta from Vienna. Kisch's report "The conjoined sisters" was published in his book "Sensation fair" during his antifascistic exile firstly 1941 in New York in English, a year later in Mexico-City in the German language. In spite of his stunt-making style Kisch's declining opposite the capitalistic marketing and opposite the disgracing people's exhibition (in this case of the Bohemian pygopage sisters) is articulated. Kisch, the founder of the socialistic literary report, died in 1948 in Prague, Czechoslovakia.

  7. [WILSON-KONOVALOV'S DISEASE IN TWO SISTERS: DIFFERENCES IN THE CLINICAL PICTURE AND SUCCESSFUL THERAPY].

    Science.gov (United States)

    Ignatova, T M; Solov'eva O V; Arion, E A; Balashova, M S; Rozina, T P

    2016-01-01

    Wilson-Konovalov's disease is a rare genetic pathology of copper metabolism that in the first place affects liver and CNS. Due to autosomal-recessive inheritance of this condition, it most frequently occurs in sibs. We report a case of Wilson-Konovalov's disease in two sisters differing in its clinical course: severe abdominal variant in the younger sister and largely neurologic form in the elder one. This observation demonstrates clinical variability of Wilson-Konovalov's disease, the possibility of its late clinical manifestation (at the age 45 years), the necessity of examination of all sibs of a proband regardless of age, and the possibility of radical improvement of prognosis even when the disease is diagnosed at the stage of decompensated liver cirrhosis.

  8. The first record of a trans-oceanic sister-group relationship between obligate vertebrate troglobites.

    Directory of Open Access Journals (Sweden)

    Prosanta Chakrabarty

    Full Text Available We show using the most complete phylogeny of one of the most species-rich orders of vertebrates (Gobiiformes, and calibrations from the rich fossil record of teleost fishes, that the genus Typhleotris, endemic to subterranean karst habitats in southwestern Madagascar, is the sister group to Milyeringa, endemic to similar subterranean systems in northwestern Australia. Both groups are eyeless, and our phylogenetic and biogeographic results show that these obligate cave fishes now found on opposite ends of the Indian Ocean (separated by nearly 7,000 km are each others closest relatives and owe their origins to the break up of the southern supercontinent, Gondwana, at the end of the Cretaceous period. Trans-oceanic sister-group relationships are otherwise unknown between blind, cave-adapted vertebrates and our results provide an extraordinary case of Gondwanan vicariance.

  9. The first record of a trans-oceanic sister-group relationship between obligate vertebrate troglobites.

    Science.gov (United States)

    Chakrabarty, Prosanta; Davis, Matthew P; Sparks, John S

    2012-01-01

    We show using the most complete phylogeny of one of the most species-rich orders of vertebrates (Gobiiformes), and calibrations from the rich fossil record of teleost fishes, that the genus Typhleotris, endemic to subterranean karst habitats in southwestern Madagascar, is the sister group to Milyeringa, endemic to similar subterranean systems in northwestern Australia. Both groups are eyeless, and our phylogenetic and biogeographic results show that these obligate cave fishes now found on opposite ends of the Indian Ocean (separated by nearly 7,000 km) are each others closest relatives and owe their origins to the break up of the southern supercontinent, Gondwana, at the end of the Cretaceous period. Trans-oceanic sister-group relationships are otherwise unknown between blind, cave-adapted vertebrates and our results provide an extraordinary case of Gondwanan vicariance.

  10. An Unusual Cause for Sister Mary Joseph’s Nodule: A Case Report

    Directory of Open Access Journals (Sweden)

    Yasser Aljehani

    2014-11-01

    Full Text Available Sister Mary Joseph’s nodule refers to palpable nodules bulging into the umbilicus as a result of metastasis from malignancy in the abdomen or pelvis. The most common primaries are in the gastrointestinal or genital tract, while other origins are considered rare. We recently treated a 71-year-old man who presented with painless umbilical swelling. Further investigation, including laboratory, radiological and histopathological exam, confirmed the diagnosis of a metastatic neuroendocrine tumor. The peculiarity of this case is that the umbilical swelling was the initial presentation of a neuroendocrine tumor and, to our knowledge, this is the first to be reported. This case demonstrates that neuroendocrine tumor is a rare cause of Sister Mary Joseph’s nodule.

  11. Short telomere length and breast cancer risk: a study in sister sets.

    Science.gov (United States)

    Shen, Jing; Terry, Mary Beth; Gurvich, Irina; Liao, Yuyan; Senie, Ruby T; Santella, Regina M

    2007-06-01

    Telomeres consist of a tandem repeats of the sequence TTAGGG at the ends of chromosomes and play a key role in the maintenance of chromosomal stability. Previous studies indicated that short telomeres are associated with increased risk for human bladder, head and neck, lung, and renal cell cancer. We investigated the association between white blood cell telomere length and breast cancer risk among 268 family sets (287 breast cancer cases and 350 sister controls). Telomere length was assessed by quantitative PCR. The mean telomere length was shorter in cases (mean, 0.70; range, 0.03-1.95) than in unaffected control sisters (mean, 0.74; range, 0.03-2.29), but no significant difference was observed (P = 0.11). When subjects were categorized according to the median telomere length in controls (0.70), affected sisters had shorter telomeres compared with unaffected sisters after adjusting for age at blood donation and smoking status [odds ratio (OR), 1.3; 95% confidence interval (95% CI), 0.9-1.8], but the association was not statistically significant. The association by quartile of telomere length (Q4 shortest versus Q1 longest) also supported an increase in risk from shorter telomere length, although the association was not statistically significant (OR, 1.6; 95% CI, 0.9-2.7). This association was more pronounced among premenopausal women (OR, 2.1; 95% CI, 0.8-5.5) than postmenopausal women (OR, 1.3; 95% CI, 0.5-3.6 for Q4 versus Q1). If these associations are replicated in larger studies, they provide modest epidemiologic evidence that shortened telomere length may be associated with breast cancer risk.

  12. 最后消息:Bodies of JFK Jr.,Wife,Sister-in-Law Found

    Institute of Scientific and Technical Information of China (English)

    Tony; Munroe

    1999-01-01

    Searchers have found the bodies of John F. Kennedy Jr., his wife CarolynBessette Kennedy and her sister Lauren as well as a large piece of their crashedplane off the coast of Martha’s Vineyard, officials said Wednesday. Massachusetts Sen. Edward Kennedy and his two sons headed for the crashsite on a U. S. Coast Guard vessel after the bodies and wreckage (残骸) were

  13. Analysis of Interpersonal Relationship in the Consumer Society Context in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    张恩秀

    2009-01-01

    Carrie's characterization is a familiar topic in the criticism in Sister Carrie. However, how it could be re-viewed in the context of the consumer society is relalively a new issue. This paper attempts to analyze the interpersonal relationship in the context of a consumer society. It explores the consumer society's influences on the lovers and family. In addition, it points out Dreiser's ambivalent attitude towards consumer ideology.

  14. Analyzing of Sister Carrie’s Independence Process from the Perspective of Feminism

    Institute of Scientific and Technical Information of China (English)

    姜新新

    2015-01-01

    "Sister Carrie" is published when the American society is in the transition from traditional industry to modern industry.Modern industrial not only provide opportunity to the development of city,but also offer some employment opportunities to the people,while the survival pressure for living is also increased.People’s thought also undergo a tremendous change.They even feel puzzled and confused.

  15. Arrangement of nuclear structures is not transmitted through mitosis but is identical in sister cells.

    Science.gov (United States)

    Orlova, Darya Yu; Stixová, Lenka; Kozubek, Stanislav; Gierman, Hinco J; Šustáčková, Gabriela; Chernyshev, Andrei V; Medvedev, Ruslan N; Legartová, Soňa; Versteeg, Rogier; Matula, Pavel; Stoklasa, Roman; Bártová, Eva

    2012-11-01

    Although it is well known that chromosomes are non-randomly organized during interphase, it is not completely clear whether higher-order chromatin structure is transmitted from mother to daughter cells. Therefore, we addressed the question of how chromatin is rearranged during interphase and whether heterochromatin pattern is transmitted after mitosis. We additionally tested the similarity of chromatin arrangement in sister interphase nuclei. We noticed a very active cell rotation during interphase, especially when histone hyperacetylation was induced or transcription was inhibited. This natural phenomenon can influence the analysis of nuclear arrangement. Using photoconversion of Dendra2-tagged core histone H4 we showed that the distribution of chromatin in daughter interphase nuclei differed from that in mother cells. Similarly, the nuclear distribution of heterochromatin protein 1β (HP1β) was not completely identical in mother and daughter cells. However, identity between mother and daughter cells was in many cases evidenced by nucleolar composition. Moreover, morphology of nucleoli, HP1β protein, Cajal bodies, chromosome territories, and gene transcripts were identical in sister cell nuclei. We conclude that the arrangement of interphase chromatin is not transmitted through mitosis, but the nuclear pattern is identical in naturally synchronized sister cells. It is also necessary to take into account the possibility that cell rotation and the degree of chromatin condensation during functionally specific cell cycle phases might influence our view of nuclear architecture.

  16. An Eco-feminist Comparison between Sister Carrie and My Antonia

    Institute of Scientific and Technical Information of China (English)

    刘翌

    2014-01-01

    According to human history, there are varieties of ways through which the feminine aspect of nature faced and in many cases, overcame oppression. One of the ways this phenomenon displays itself is in the literary works that we deem as realis⁃tic and an expression of the norms and customs of the society in question. Sister Carrie and My Antonia are two such literary pieces that embody the struggles and triumphs of women in the 19th and most of the early 20th century. In creating such monu⁃mental and naturalistic adaptations, both authors are able to present the case of two migratory women from different backgrounds but confined by the norms and mannerisms of the society around them. The struggles that each of these characters undergoes is an expression of the underlying constraints that the paternal and chauvinistic society of their time places upon both women and the natural world. The eco-feminist agenda, however, gets a more elaborate representation in My Antonia than in Sister Carrie due to a variety of factors that serve to illuminate the differences between these two iconic stories. This paper makes a thorough comparison between two literary works—Sister Carrie by Theodore Dreiser and My Antonia by Willa Cather from the perspec⁃tive of eco-feminism.

  17. Secret Sisters: Women Religious under European Communism Collection at the Catholic Theological Union

    Directory of Open Access Journals (Sweden)

    Vincent P. Tinerella

    2010-10-01

    Full Text Available After the fall of Communism in Eastern Europe, Pope John Paul II asked Catholics around the world to assist members of the Church who had suffered under the yoke of communist oppression as a result of their commitment to Catholicism. Sr. Margaret Savoie, and Sr. Margaret Nacke, Sisters of St. Joseph, Concordia, Kansas, decided that the experiences of Catholic women in religious communities – “surviving sisters” – was an important story that needed to be documented, preserved, and made available for future generations and researchers. In 2003, Sisters Mary and Margaret began their research, recording the plight of Catholic sisters in eight countries, Bulgaria, Czech Republic, Hungary, Lithuania, Romania, Slovakia, and the Ukraine, from the rise of Stalin until the collapse of European communism. Over 200 testimonials now reside at the Paul Bechtold Library at the Catholic Theological Union in Chicago under the auspices of the library’s archivist, Dr. Kenneth O’Malley, C.P. , and their work has been made into a national and award-winning documentary film. .

  18. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1983

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa NWR, Cedar Point NWR, and West Sister Island NWR outlines Refuge accomplishments during the 1983 calendar year. The report...

  19. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1979

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa NWR, Cedar Point NWR, West Sister Island NWR, Navarre Marsh, and Darby Marsh outlines Refuge accomplishments during the 1979...

  20. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1985

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa NWR, Cedar Point NWR, and West Sister Island NWR outlines Refuge accomplishments during the 1985 calendar year. The report...

  1. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1987

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa NWR, Cedar Point NWR, and West Sister Island NWR outlines Refuge accomplishments during the 1987 calendar year. The report...

  2. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1986

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa NWR, Cedar Point NWR, and West Sister Island NWR outlines Refuge accomplishments during the 1986 calendar year. The report...

  3. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa, Cedar Point, and West Sister Island National Wildlife Refuges outlines Refuge accomplishments during the 1989 calendar year....

  4. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1982

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa NWR, Cedar Point NWR, and West Sister Island NWR outlines Refuge accomplishments during the 1982 calendar year. The report...

  5. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1980

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa NWR, Cedar Point NWR, West Sister Island NWR, Navarre Marsh, and Darby Marsh outlines Refuge accomplishments during the 1980...

  6. Ottawa National Wildlife Refuge Complex (Ottawa, Cedar Point, West Sister Island NWR's): Annual narrative report: Calendar year 1981

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa NWR, Cedar Point NWR, and West Sister Island NWR outlines Refuge accomplishments during the 1981 calendar year. The report...

  7. Three sisters with very-late-onset major depression and parkinsonism.

    Science.gov (United States)

    Sechi, GianPietro; Antonio Cocco, Giovanni; Errigo, Alessandra; Deiana, Luca; Rosati, Giulio; Agnetti, Virgilio; Stephen Paulus, Kay; Mario Pes, Giovanni

    2007-03-01

    Familiar Parkinson's disease has an age of onset from the second to the sixth decade, whereas Wilson's disease (WD) usually presents in the first decade of life. We studied three sisters with a form of very-late-onset major depression and parkinsonism with probable linkage to ATP7B gene. Molecular studies demonstrated a nucleotide deletion at the 5'UTR region in a single allele of ATP7B gene. They did not have a family history of WD, or markers indicative for copper deposition in peripheral tissues. We suggest that single allele mutations of ATP7B gene may confer a susceptibility for late-onset major depression and parkinsonism.

  8. Two Cases of Endometrial Cancer in Twin Sisters with Myotonic Dystrophy

    Directory of Open Access Journals (Sweden)

    Ezra Y. Koh

    2016-01-01

    Full Text Available We describe two cases of endometrial cancer (EC occurring in nulligravid twin sisters with myotonic dystrophy. Both tested negative for Lynch syndrome and both were treated with laparoscopic hysterectomy with bilateral salpingooophorectomy and adjuvant radiotherapy. Although EC tends to run in families, the diagnosis in itself is not considered sufficient cause for screening or prophylactic measures in close relatives. However, the presence of additional risk factors, such as nulligravidity and myotonic dystrophy in the underlying cases, may call for extra vigilance in first-degree family members.

  9. Shigella strains are not clones of Escherichia coli but sister species in the genus Escherichia.

    Science.gov (United States)

    Zuo, Guanghong; Xu, Zhao; Hao, Bailin

    2013-02-01

    Shigella species and Escherichia coli are closely related organisms. Early phenotyping experiments and several recent molecular studies put Shigella within the species E. coli. However, the whole-genome-based, alignment-free and parameter-free CVTree approach shows convincingly that four established Shigella species, Shigella boydii, Shigella sonnei, Shigella felxneri and Shigella dysenteriae, are distinct from E. coli strains, and form sister species to E. coli within the genus Escherichia. In view of the overall success and high resolution power of the CVTree approach, this result should be taken seriously. We hope that the present report may promote further in-depth study of the Shigella-E. coli relationship.

  10. The Naturalism in Tess of the D'Urbervilles and Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    原燕婷

    2010-01-01

    @@ Nowadays, literature study is almost perfectly and profoundly cultivated by scholars and educators all around the world, thus, the exploration in this field is progressing much slower, and comparison literature is raising its head steadily in modern literature circles. Accordingly, the comparison between Tess of the d'Urbervilles and Sister Carrie is rarely done, although the naturalism in the two novels has been colossally studied and nearly reached the peak of its maxim, the author still feel obliged to connect them through the clue-"naturalism" to attain a unique but unanimous effect of literature study.

  11. Emergence of ethnochoreology internationally: The Janković sisters, Maud Karpeles, and Gertrude Kurath

    Directory of Open Access Journals (Sweden)

    Dunin Elsie Ivancich

    2014-01-01

    Full Text Available A fifty-year (1962-2012 period has been shown as a history of ethnochoreology supported by living memories of members of the International Council for Traditional Music (ICTM Study Group on Ethnochoreology. Recently uncovered and juxtapositioned correspondence of three predecessors within earlier years of the International Folk Music Council (IFMC broadens the history. This article reveals the emergence of ethnochoreology during the 1950s with publications of the two Janković sisters in Serbia with that of Gertrude Kurath in the United States, alongside correspondence with Maud Karpeles, the unheralded founder of the IFMC.

  12. Diet transiently improves migraine in two twin sisters: possible role of ketogenesis?

    Science.gov (United States)

    Di Lorenzo, Cherubino; Currà, Antonio; Sirianni, Giulio; Coppola, Gianluca; Bracaglia, Martina; Cardillo, Alessandra; De Nardis, Lorenzo; Pierelli, Francesco

    2013-01-01

    The ketogenic diet is a high-fat, low-carbohydrate diet long used to treat refractory epilepsy; ketogenesis (ketone body formation) is a physiological phenomenon also observed in patients following lowcarbohydrate, low-calorie diets prescribed for rapid weight loss. We report the case of a pair of twin sisters, whose high-frequency migraine improved during a ketogenic diet they followed in order to lose weight. The observed time-lock between ketogenesis and migraine improvement provides some insight into how ketones act to improve migraine.

  13. [Partial lipodystrophy in two HLA identical sisters with hypocomplementemia and nephropathy].

    Science.gov (United States)

    Peces, R

    2002-01-01

    Partial lipodystrophy is a rare disorder with both autosomal recessive and familial forms. The cutaneous findings, which are often subtle, consist of gradual loss of subcutaneous fat from the face and upper body. Low levels of C3 and the presence of C3NeF help to identify these patients. Associated systemic abnormalities include the development of membranoproliferative glomerulonephritis, insulin resistance and an increased incidence of autoimmune diseases. We report here two HLA identical sisters with the typical features of partial lipodystrophy associated with recurrent infections, low levels of C3, and nephropathy. Our data suggest an autosomal recessive transmission. We discuss the genetic and molecular basis of this rare association.

  14. The Conflict Between the Traditional Value and Reality In Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    顾庆媛; 陈飞; 孙胜强; 常利娜; 张罗斌

    2009-01-01

    Theodore Dreiser relates a story of Carrie's rise from a poor country girl to a Broadway star in Sister Carrie.An attempt is rnade in this paper to analyze the cold society.Byway of analyzing this unequal and cruel reality to prove:in the world only the fittest can survive.the standards and requirements of morality are challenged and the traditional value is suspected.In the cold reality.any way that Can protect oneself or survivein the wodd is sensible,morality and traditional value are weak and mcaningless.

  15. FTO gene SNPs associated with extreme obesity in cases, controls and extremely discordant sister pairs

    Directory of Open Access Journals (Sweden)

    Zhao Hongyu

    2008-01-01

    Full Text Available Abstract Background FTO is a gene located in chromosome region 16q12.2. Recently two studies have found associations of several single nucleotide polymorphisms (SNPs in FTO with body mass index (BMI and obesity, particularly rs1421085, rs17817449, and rs9939609. Methods We examined these three SNPs in 583 extremely obese women with current BMI greater than 35 kg/m2 and lifetime BMI greater than 40 kg/m2, and 544 controls who were currently normal weight (BMI2 and had never been overweight during their lifetimes. Results We detected highly significant associations of obesity with alleles in all three SNPs (p -9. The strongest association was with rs1421085 (p = 3.04 × 10-10, OR = 1.75, CI = 1.47–2.08. A subset of 99 cases had extremely discordant sisters with BMI2. The discordant sisters differed in allele and genotype frequencies in parallel with the overall case and control sample. The strongest association was with rs17817449 (z = 3.57, p = 3.6 × 10-4. Conclusion These results suggest common variability in FTO is associated with increased obesity risk or resistance and may in part account for differences between closely related individuals.

  16. Familial hypomagnesemia with hypercalciuria and nephrocalcinosis: variable phenotypic expression in three affected sisters from Mexican ancestry.

    Science.gov (United States)

    Arteaga, María E; Hunziker, Walter; Teo, Audrey S M; Hillmer, Axel M; Mutchinick, Osvaldo M

    2015-02-01

    Familial hypomagnesemia with hypercalciuria and nephrocalcinosis is a rare autosomal recessive renal disease caused by mutations in genes for the tight junction transmembrane proteins Claudin-16 (CLDN16) and Claudin-19 (CLDN19). We present the first case report of a Mexican family with three affected sisters carrying a p.Gly20Asp mutation in CLDN19 whose heterozygous mother showed evident hypercalciuria and normal low magnesemia without any other clinical, laboratory, and radiological symptoms of renal disease making of her an unsuitable donor. The affected sisters showed variable phenotypic expression including age of first symptoms, renal urinary tract infections, nephrolithiasis, nephrocalcinosis, and eye symptoms consisting in retinochoroiditis, strabismus, macular scars, bilateral anisocoria, and severe myopia and astigmatism. End stage renal disease due to renal failure needed kidney transplantation in the three of them. Interesting findings were a heterozygous mother with asymptomatic hypercalciuria warning on the need of carefully explore clinical, laboratory, kidney ultrasonograpy, and mutation status in first degree asymptomatic relatives to avoid inappropriate kidney donors; an evident variable phenotypic expression among patients; the identification of a mutation almost confined to Spanish cases and a 3.5 Mb block of genomic homozygosis strongly suggesting a common remote parental ancestor for the gene mutation reported.

  17. Exploring the origin of the latitudinal diversity gradient: Contrasting the sister fern genera Phegopteris and Pseudophegopteris

    Institute of Scientific and Technical Information of China (English)

    Harald SCHNEIDER; Li-Juan HE; Jeannine MARQUARDT; Li WANG; Jochen HEINRICHS; Sabine HENNEQUIN; Xian-Chun ZHANG

    2013-01-01

    The origin of the latitudinal biodiversity gradient has been studied using various approaches.Here,we employ a comparative phylogenetic approach to infer evidence for the hypothesis that differences in diversification rates are one of the main factors contributing to the assembly of this gradient.We infer the phylogeny of the two sister genera Phegopteris and Pseudophegopteris.The two genera are distinct in their species richness (4 vs.20 spp.) and their preferences to temperate to subtropical (Phegopteris) or tropical climates (Pseudophegopteris).Using sequences of three plastid DNA regions,we confirm the monophyly of each genus and infer the inter-and intra-generic phylogenetic differentiation of the sister clades.We recover evidence for distinct net-diversification rate between the two genera,which may be caused either by a higher extinction risk of temperate Phegopteris or a higher speciation rate of tropical Pseudophegopteris.We discuss our results in the context of our current knowledge on the speciation processes of ferns.We conclude on the crucial influence of other factors such as the rise of the Himalaya on the diversification of these fems.

  18. Three Sisters Mountain Village development transformation of old coal mine properties into modern day use

    Energy Technology Data Exchange (ETDEWEB)

    Fox, B. [Golder Paste Technology Ltd., Sudbury, ON (Canada)

    2006-07-01

    This paper discussed the development of the Three Sisters Mountain Village, located close to Canmore, Alberta. The paper provided the history and background of the mining and development of the site. It discussed underground mining methodology and planned housing and industrial development. The village included plans for 10,000 residential homes, 2 golf courses, a wellness centre, a school, commercial buildings and wildlife corridors. Environmental concerns were also addressed, as Canmore contains a series of natural wildlife corridors, which act as migration and travelling routes for elk and deer as well as cougars, grizzly bears, and other animals. These routes are essential for the survival of the different herds and animal species. The development progress strategy was discussed. The Three Sisters Mountain Village Development commissioned Golder Associates Ltd. to study and address the environmental concerns of the stakeholders regarding the migrating routes of wildlife. Mining works mitigation, including mapping of the constraint zones, knowledge of subsidence issues and the effects of subsidence on structural stress and the ability to analysis field data to predict potential problems was also presented along with a methodology for mitigation and choice of backfill material to be used to fill the mine workings. The advantages of using concrete paste backfill were also identified.

  19. Different parasite faunas in sympatric populations of sister hedgehog species in a secondary contact zone.

    Directory of Open Access Journals (Sweden)

    Miriam Pfäffle

    Full Text Available Providing descriptive data on parasite diversity and load in sister species is a first step in addressing the role of host-parasite coevolution in the speciation process. In this study we compare the parasite faunas of the closely related hedgehog species Erinaceus europaeus and E. roumanicus from the Czech Republic where both occur in limited sympatry. We examined 109 hedgehogs from 21 localities within this secondary contact zone. Three species of ectoparasites and nine species of endoparasites were recorded. Significantly higher abundances and prevalences were found for Capillaria spp. and Brachylaemus erinacei in E. europaeus compared to E. roumanicus and higher mean infection rates and prevalences for Hymenolepis erinacei, Physaloptera clausa and Nephridiorhynchus major in E. roumanicus compared to E. europaeus. Divergence in the composition of the parasite fauna, except for Capillaria spp., which seem to be very unspecific, may be related to the complicated demography of their hosts connected with Pleistocene climate oscillations and consequent range dynamics. The fact that all parasite species with different abundances in E. europaeus and E. roumanicus belong to intestinal forms indicates a possible diversification of trophic niches between both sister hedgehog species.

  20. A novel sister clade to the enterobacteria microviruses (family Microviridae) identified in methane seep sediments.

    Science.gov (United States)

    Bryson, Samuel Joseph; Thurber, Andrew R; Correa, Adrienne M S; Orphan, Victoria J; Vega Thurber, Rebecca

    2015-10-01

    Methane seep microbial communities perform a key ecosystem service by consuming the greenhouse gas methane prior to its release into the hydrosphere, minimizing the impact of marine methane sources on our climate. Although previous studies have examined the ecology and biochemistry of these communities, none has examined viral assemblages associated with these habitats. We employed virus particle purification, genome amplification, pyrosequencing and gene/genome reconstruction and annotation on two metagenomic libraries, one prepared for ssDNA and the other for all DNA, to identify the viral community in a methane seep. Similarity analysis of these libraries (raw and assembled) revealed a community dominated by phages, with a significant proportion of similarities to the Microviridae family of ssDNA phages. We define these viruses as the Eel River Basin Microviridae (ERBM). Assembly and comparison of 21 ERBM closed circular genomes identified five as members of a novel sister clade to the Microvirus genus of Enterobacteria phages. Comparisons among other metagenomes and these Microviridae major-capsid sequences indicated that this clade of phages is currently unique to the Eel River Basin sediments. Given this ERBM clade's relationship to the Microviridae genus Microvirus, we define this sister clade as the candidate genus Pequeñovirus.

  1. Test for Chemical Induction of Chromosome Aberrations in Cultured Chinese Hamster (CHO) Cells With and Without Metabolic Activation, Test Acticle: Ethylenediamine Dinitrate (EDDN)

    Science.gov (United States)

    2010-02-25

    chromosomes leading to four-armed configurations. This could be asymmetrical with formation of a dicentric and an acentric chromatid, ifunion is complete, or...a shortened monocentric chromosome , and where there is no sister chromatid union. Dicentric - an asymmetrical exchange between two chromosomes ...a shortened monocentric chromosome , and where there is no sister chromatid union. Dicentric - an asymmetrical exchange between two chromosomes

  2. Novel HPS6 mutations identified by whole-exome sequencing in two Japanese sisters with suspected ocular albinism.

    Science.gov (United States)

    Miyamichi, Daisuke; Asahina, Miki; Nakajima, Junya; Sato, Miho; Hosono, Katsuhiro; Nomura, Takahito; Negishi, Takashi; Miyake, Noriko; Hotta, Yoshihiro; Ogata, Tsutomu; Matsumoto, Naomichi

    2016-09-01

    Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder characterized by oculocutaneous albinism, platelet dysfunction and ceroid deposition. We report suspected ocular albinism in two Japanese sisters, caused by mutations in the HPS6 (Hermansky-Pudlak syndrome 6) gene. Trio-based whole-exome sequencing (WES) identified novel compound heterozygous mutations in HPS6 (c.1898delC: mother origin and c.2038C>T: father origin) in the two sisters. To date, 10 associated mutations have been detected in HPS6. Although we detected no general manifestations, including platelet dysfunction, in the sisters, even in long-term follow-up, we established a diagnosis of HPS type 6 based on the HPS6 mutations and absence of dense bodies in the platelets, indicating that WES can identify cases of HPS type 6. To the best of our knowledge, this is the first report of HPS6 mutations in Japanese patients.

  3. Wanita Penjaja Agama Kepemimpinan Sister Aimee Semple McPherson dalam Novel: Elmer Gentry, Oil!, dan The Loved One

    Directory of Open Access Journals (Sweden)

    Nursaktiningrum Nursaktiningrum

    2010-06-01

    Full Text Available This article studies how three famous American writers portray Sister McPherson (1890-1944, a controversial female religious leader, in their novels. Placing the novels written by Lewis, Sinclair, and Waugh in the context of American society, this study aims to reveal how Sister McPherson crossed gender boundaries and reinvented tradition in American religious institutions. By combining religious teachings and the advancement of popular culture, she broke the old religious tradition and succeeded in popularizing the religion she embraced.

  4. Pseudoxanthoma elasticum: clinical, histologic, and genetic studies--a report of two sisters.

    Science.gov (United States)

    Kaimbo, Dieudonne Kaimbo Wa; Mutosh, Anne; Leys, Anita; Parys-van Ginderdeuren, Rita; Bergen, A A B

    2011-01-01

    CASE 1: A 24-year-old black woman was referred to our clinic in September 1999 by the department of dermatology. She was referred to confirm the diagnosis of pseudoxanthoma elasticum (PXE). Her medical history was normal. Dermatologic examination revealed confluent papules that gave the skin a "plucked chicken" appearance on the flexural surfaces in the neck, axillae, clavicle, thigh, and periumbilical area (Figure 1). The patient stated that the changes in her skin had begun in the periumbilical region at about 5 years of age and had since been slowly progressive. Physical examination showed brownish black pigmentation on the left side of the face, left eyelid, and left sclera, which was diagnosed as Nevus of Ota (Figure 2). Her visual acuity was 20/10 in both eyes, with no afferent pupillary defect. Intraocular pressure in both eyes was normal. Slit lamp examination showed no abnormalities. Findings from fundus examination revealed angioid streaks that formed an incomplete ring around the optic disc and anteriorly radiated toward the equator of the globe, multiple calcified drusen-like structures, and "peau d'orange" changes. Skin biopsy (skin tissue from the neck) was taken and the diagnosis of PXE was confirmed. Histopathologic findings revealed calcification of the elastic fibers and abnormalities of the collagen (Figure 3). The patient was not known to have sickle cell anemia or sickle cell trait, and her blood pressure levels had never elevated. Other systemic causes of angioid streaks were excluded by findings from extensive laboratory examination. Her relatives were asked to come in for examination but lived far away. One of the patient's sisters lived in Kinshasa, Africa, however, and is presented in case 2. CASE 2: The 27-year-old sister of the previous patient was examined on April 19, 2000. At examination, she was found to have PXE. Her medical history was significant for systemic hypertension since 1998 and genital hemorrhage. She underwent an

  5. Incestuous sisters: mate preference for brothers over unrelated males in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Adeline Loyau

    Full Text Available The literature is full of examples of inbreeding avoidance, while recent mathematical models predict that inbreeding tolerance or even inbreeding preference should be expected under several realistic conditions like e.g. polygyny. We investigated male and female mate preferences with respect to relatedness in the fruit fly D. melanogaster. Experiments offered the choice between a first order relative (full-sibling or parent and an unrelated individual with the same age and mating history. We found that females significantly preferred mating with their brothers, thus supporting inbreeding preference. Moreover, females did not avoid mating with their fathers, and males did not avoid mating with their sisters, thus supporting inbreeding tolerance. Our experiments therefore add empirical evidence for inbreeding preference, which strengthens the prediction that inbreeding tolerance and preference can evolve under specific circumstances through the positive effects on inclusive fitness.

  6. Sibling recognition and the development of identity: intersubjective consequences of sibling differentiation in the sister relationship.

    Science.gov (United States)

    Vivona, Jeanine M

    2013-01-01

    Identity is, among other things, a means to adapt to the others around whom one must fit. Psychoanalytic theory has highlighted ways in which the child fits in by emulating important others, especially through identification. Alternately, the child may fit into the family and around important others through differentiation, an unconscious process that involves developing or accentuating qualities and desires in oneself that are expressly different from the perceived qualities of another person and simultaneously suppressing qualities and desires that are perceived as similar. With two clinical vignettes centered on the sister relationship, the author demonstrates that recognition of identity differences that result from sibling differentiation carries special significance in the sibling relationship and simultaneously poses particular intersubjective challenges. To the extent that the spotlight of sibling recognition delimits the lateral space one may occupy, repeatedly frustrated desires for sibling recognition may have enduring consequences for one's sense of self-worth and expectations of relationships with peers and partners.

  7. Early Development of Squamous Cell Carsinoma in Two Sister Cases with pidermodysplasia Verruciformis

    Directory of Open Access Journals (Sweden)

    Ömer Çalka

    2010-06-01

    Full Text Available Epidermodysplasia verruciformis (Lewandowsky-Lutz syndrome is an uncommon disease characterized by multiple plane warts, pityriasis versicolor-like lesions, defects of cell-mediated immunity, and tendency to develop skin malignancies, primarily on sun-exposed areas. Most commonly it is inherited as an autosomal recessive trait. Squamous cell carcinoma is the most common type of skin cancer found in patient with epidermodysplasia verruciformis. Human papilloma virus 5, 8, and 47 are found in more than 90% of epidermodysplasia verruciformis skin cancers. Treatment for epidermodysplasia verruciformis consists largely of preventive measures. Photoprotection remains essential for management. In this report, two sister case of epidermodisplasia verruciformis with plane warts, pityriasis versicolor-like lesions, and squamous cell carcinomas on sun-exposed areas of skin was presented for it is a rarely encountered disease and associated with early development of malignancy.

  8. The Brotherhood of Freemason Sisters. Gender, Secrecy, and Fraternity in Italian Masonic Lodges

    OpenAIRE

    Bounissou, Cédric

    2017-01-01

    Lilith Mahmud, The Brotherhood of Freemason Sisters. Gender, Secrecy, and Fraternity in Italian Masonic Lodges, Chicago-London, University of Chicago Press, 2014, 250 p., bibl., index Depuis sa création au xviiie siècle, la franc-maçonnerie a joué un rôle important dans la formation de la démocratie moderne, en favorisant l’émergence de l’espace public tel que le définit Jürgen Habermas (p. 8). En décrivant la franc-maçonnerie comme « la société secrète occidentale par excellence, celle qui, ...

  9. Comparing methods of estimating strength parameters for fissured clays at Seven Sisters Generating Station

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, D.P.; Yereniuk, V.A. [Manitoba Hydro, Winnipeg, MB (Canada)

    2003-07-01

    Some instabilities have been observed at several dyke locations at the Seven Sisters Generating Station, Manitoba since construction in the late 1940s. The foundations of the dykes are fissured plastic clays. Slope stabilizing methods have been proposed by a number of researchers since the late 1970s for estimating strength parameters for fissured plastic clays. This paper reports on four methods which were used for estimating Mohr-Coulomb strength parameters for stability analyses involving nine dyke locations where instability has been reported in the past. Correlation is established between the calculated safety factors and observed performance in an effort to determine the most appropriate method for this site. It was determined that the most appropriate method was that proposed by P.J. Rivard and Y.Lu in the late 1970s. 16 refs., 1 tab., 7 figs.

  10. Two sisters with macular dystrophy caused by the 3243A>G mitochondrial DNA mutation.

    Science.gov (United States)

    Sánchez-Gutiérrez, V; García-Montesinos, J; Pardo-Muñoz, A

    2016-05-01

    Two sisters of 54 and 60years old, with a history of diabetes and deafness, consulted for decreased visual acuity (VA). Funduscopic examination revealed patchy areas of chorioretinal atrophy with annular arrangement around the fovea. Genetic study identified the heteroplasmic mutation 3243A>G in mitochondrial DNA, which supports syndrome maternally inherited diabetes and deafness (MIDD) or Ballinger-Wallace disease. The finding of such macular disorders, especially in the presence of diabetes mellitus and deafness, should suggest the performing of a mitochondrial genome screening to identify this unusual syndrome. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  11. Ice Volumes on Cascade Volcanoes: Mount Rainier, Mount Hood, Three Sisters, and Mount Shasta

    Science.gov (United States)

    Driedger, Carolyn L.; Kennard, Paul M.

    1986-01-01

    During the eruptions of Mount St. Helens the occurrence of floods and mudflows made apparent the need for predictive water-hazard analysis of other Cascade volcanoes. A basic requirement for such analysis is information about the volumes and distributions of snow and ice on other volcanoes. A radar unit contained in a backpack was used to make point measurements of ice thickness on major glaciers of Mount Rainier, Wash.; Mount Hood, Oreg.; the Three Sisters, Oreg.; and Mount Shasta, Calif. The measurements were corrected for slope and were used to develop subglacial contour maps from which glacier volumes were measured. These values were used to develop estimation methods for finding volumes of unmeasured glaciers. These methods require a knowledge of glacier slope, altitude, and area and require an estimation of basal shear stress, each estimate derived by using topographic maps updated by aerial photographs. The estimation methods were found to be accurate within ?20 percent on measured glaciers and to be within ?25 percent when applied to unmeasured glaciers on the Cascade volcanoes. The estimation methods may be applicable to other temperate glaciers in similar climatic settings. Areas and volumes of snow and ice are as follows: Mount Rainier, 991 million ft2, 156 billion ft3; Mount Hood, 145 million ft2, 12 billion ft3; Three Sisters, 89 million ft2, 6 billion ft3; and Mount Shasta, 74 million ft2, 5 billion ft3. The distribution of ice and firn patches within 58 glacierized basins on volcanoes is mapped and listed by altitude and by watershed to facilitate water-hazard analysis.

  12. EPRI/DOE High Burnup Fuel Sister Pin Test Plan Simplification and Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Saltzstein, Sylvia J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorenson, Ken B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hanson, Brady [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billone, Mike [Argonne National Lab. (ANL), Argonne, IL (United States); Scaglione, John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Rose [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-07-01

    The EPRI/DOE High Burnup Confirmatory Data Project (herein called the "Demo") is a multi-year, multi-entity confirmation demonstration test with the purpose of providing quantitative and qualitative data to show how high-burnup fuel ages in dry storage over a ten-year period. The Demo involves obtaining 32 assemblies of high-burnup PWR fuel of four common cladding alloys from the North Anna Nuclear Power Plant, drying them according to standard plant procedures, and then storing them in an NRC-licensed TN-3 2B cask on the North Anna dry storage pad for ten years. After the ten-year storage time, the cask will be opened and the rods will be examined for signs of aging. Twenty-five rods from assemblies of similar claddings, in-reactor placement, and burnup histories (herein called "sister rods") have been shipped from the North Anna Nuclear Power Plant and are currently being nondestructively tested at Oak Ridge National Laboratory. After the non-destructive testing has been completed for each of the twenty-five rods, destructive analysis will be performed at ORNL, PNNL, and ANL to obtain mechanical data. Opinions gathered from the expert interviews, ORNL and PNNL Sister Rod Test Plans, and numerous meetings has resulted in the Simplified Test Plan described in this document. Some of the opinions and discussions leading to the simplified test plan are included here. Detailed descriptions and background are in the ORNL and PNNL plans in the appendices . After the testing described in this simplified test plan h as been completed , the community will review all the collected data and determine if additional testing is needed.

  13. Phylogenomic analyses support the position of turtles as the sister group of birds and crocodiles (Archosauria

    Directory of Open Access Journals (Sweden)

    Chiari Ylenia

    2012-07-01

    Full Text Available Abstract Background The morphological peculiarities of turtles have, for a long time, impeded their accurate placement in the phylogeny of amniotes. Molecular data used to address this major evolutionary question have so far been limited to a handful of markers and/or taxa. These studies have supported conflicting topologies, positioning turtles as either the sister group to all other reptiles, to lepidosaurs (tuatara, lizards and snakes, to archosaurs (birds and crocodiles, or to crocodilians. Genome-scale data have been shown to be useful in resolving other debated phylogenies, but no such adequate dataset is yet available for amniotes. Results In this study, we used next-generation sequencing to obtain seven new transcriptomes from the blood, liver, or jaws of four turtles, a caiman, a lizard, and a lungfish. We used a phylogenomic dataset based on 248 nuclear genes (187,026 nucleotide sites for 16 vertebrate taxa to resolve the origins of turtles. Maximum likelihood and Bayesian concatenation analyses and species tree approaches performed under the most realistic models of the nucleotide and amino acid substitution processes unambiguously support turtles as a sister group to birds and crocodiles. The use of more simplistic models of nucleotide substitution for both concatenation and species tree reconstruction methods leads to the artefactual grouping of turtles and crocodiles, most likely because of substitution saturation at third codon positions. Relaxed molecular clock methods estimate the divergence between turtles and archosaurs around 255 million years ago. The most recent common ancestor of living turtles, corresponding to the split between Pleurodira and Cryptodira, is estimated to have occurred around 157 million years ago, in the Upper Jurassic period. This is a more recent estimate than previously reported, and questions the interpretation of controversial Lower Jurassic fossils as being part of the extant turtles radiation

  14. Yeast Interacting Proteins Database: YDR267C, YHR122W [Yeast Interacting Proteins Database

    Lifescience Database Archive (English)

    Full Text Available ister chromatid cohesion; synthetically lethal with RFC5, an RF-C subunit that links...uired for establishment of sister chromatid cohesion; synthetically lethal with RFC5, an RF-C subunit that links

  15. Using ecological niche models and niche analyses to understand speciation patterns: the case of sister neotropical orchid bees.

    Directory of Open Access Journals (Sweden)

    Daniel P Silva

    Full Text Available The role of past connections between the two major South American forested biomes on current species distribution has been recognized a long time ago. Climatic oscillations that further separated these biomes have promoted parapatric speciation, in which many species had their continuous distribution split, giving rise to different but related species (i.e., different potential distributions and realized niche features. The distribution of many sister species of orchid bees follow this pattern. Here, using ecological niche models and niche analyses, we (1 tested the role of ecological niche differentiation on the divergence between sister orchid-bees (genera Eulaema and Eufriesea from the Amazon and Atlantic forests, and (2 highlighted interesting areas for new surveys. Amazonian species occupied different realized niches than their Atlantic sister species. Conversely, species of sympatric but distantly related Eulaema bees occupied similar realized niches. Amazonian species had a wide potential distribution in South America, whereas Atlantic Forest species were more limited to the eastern coast of the continent. Additionally, we identified several areas in need of future surveys. Our results show that the realized niche of Atlantic-Amazonian sister species of orchid bees, which have been previously treated as allopatric populations of three species, had limited niche overlap and similarity. These findings agree with their current taxonomy, which treats each of those populations as distinct valid species.

  16. Using ecological niche models and niche analyses to understand speciation patterns: the case of sister neotropical orchid bees.

    Science.gov (United States)

    Silva, Daniel P; Vilela, Bruno; De Marco, Paulo; Nemésio, André

    2014-01-01

    The role of past connections between the two major South American forested biomes on current species distribution has been recognized a long time ago. Climatic oscillations that further separated these biomes have promoted parapatric speciation, in which many species had their continuous distribution split, giving rise to different but related species (i.e., different potential distributions and realized niche features). The distribution of many sister species of orchid bees follow this pattern. Here, using ecological niche models and niche analyses, we (1) tested the role of ecological niche differentiation on the divergence between sister orchid-bees (genera Eulaema and Eufriesea) from the Amazon and Atlantic forests, and (2) highlighted interesting areas for new surveys. Amazonian species occupied different realized niches than their Atlantic sister species. Conversely, species of sympatric but distantly related Eulaema bees occupied similar realized niches. Amazonian species had a wide potential distribution in South America, whereas Atlantic Forest species were more limited to the eastern coast of the continent. Additionally, we identified several areas in need of future surveys. Our results show that the realized niche of Atlantic-Amazonian sister species of orchid bees, which have been previously treated as allopatric populations of three species, had limited niche overlap and similarity. These findings agree with their current taxonomy, which treats each of those populations as distinct valid species.

  17. Historical biogeography and diversification of truffles in the Tuberaceae and their newly identified Southern hemisphere sister lineage

    Science.gov (United States)

    Gregory Bonito; Matthew E. Smith; Michael Nowak; Rosanne A. Healy; Gonzalo Guevara; Efren Cazares; Akihiko Kinoshita; Eduardo R. Nouhra; Laura S. Dominguez; Leho Tedersoo; Claude Murat; Yun Wang; Baldomero Arroyo Moreno; Donald H. Pfister; Kazuhide Nara; Alessandra Zambonelli; James M. Trappe; Rytas. Vilgalys

    2013-01-01

    In this study we reassessed the biogeography and origin of the Tuberaceae and their relatives using multiple loci and a global sampling of taxa. Multiple independent transitions from an aboveground to a belowground truffie fruiting body form have occurred in the Tuberaceae and in its newly recognized sister lineage...

  18. Lost Women in Social Transitional Period-A Comparative Study of the Tragic Fate of Sister Carrie and Guo Haizao

    Institute of Scientific and Technical Information of China (English)

    陈晶晶

    2014-01-01

    Sister Carrie and Dwelling depict two heroines who share similarities in many aspects. They all live in the social transi-tional period and suffer a lot. This paper will make a comparison about the two ladies’tragic fates and aims to investigate the im-pact on females brought about by the social transition.

  19. Phylogenetic analysis of seven WRKY genes across the palm subtribe Attaleinae (Areceaceae) identifies Syagrus as sister to the coconut

    Science.gov (United States)

    The origins of the coconut (Cocos nucifera) have been one of the "abominable mysteries" of palm systematics for decades. Previous studies with predominantly plastid genes have indicated an American ancestry for the coconut but with weak support and ambiguous sister relationships. We used primers d...

  20. Comparative phylogeography of sympatric sister species, Clevelandia ios and Eucyclogobius newberryi (Teleostei, Gobiidae), across the California Transition Zone.

    Science.gov (United States)

    Dawson, M N; Louie, K D; Barlow, M; Jacobs, D K; Swift, C C

    2002-06-01

    It is paradigmatic in marine species that greater dispersal ability often, but not always, results in greater gene flow and less population structure. Some of the exceptions may be attributable to studies confounded by comparison of species with dissimilar evolutionary histories, i.e. co-occurring species that are not closely related or species that are closely related but allopatric. Investigation of sympatric sister species, in contrast, should allow differences in phylogeographic structure to be attributed reliably to recently derived differences in dispersal ability. Here, using mitochondrial DNA control region sequence, we first confirm that Clevelandia ios and Eucyclogobius newberryi are sympatric sister taxa, then demonstrate considerably shallower phylogeographic structure in C. ios than in E. newberryi. This shallower phylogeographic structure is consistent with the higher dispersal ability of C. ios, which most likely results from the interaction of habitat and life-history differences between the species. We suggest that the paradigm will be investigated most rigorously by similar studies of other sympatric sister species, appended by thorough ecological studies, and by extending this sister-taxon approach to comparative phylogeographic studies of monophyletic clades of sympatric species.

  1. An Evaluation of Parental Assessment of the Big Brothers/Big Sisters Program in New York City.

    Science.gov (United States)

    Frecknall, Peter; Luks, Alan

    1992-01-01

    Parents rated impact of Big Brother/Big Sister program on children along variables of school attendance, grades, family relationship, friendship, self-esteem, staying out of trouble, being responsible, frequency of contact, and length of time in program. Although children were rated as benefiting significantly from program, children's frequency of…

  2. A Case of Maternal Half-sisters Sharing Alleles at 18 X-chromosomal Short Tandem Repeat Loci

    Directory of Open Access Journals (Sweden)

    Qiu-Ling Liu

    2016-01-01

    Full Text Available Analysis of X-chromosome short tandem repeats (STRs is very helpful in deficiency paternity testing. Here, we reported a case of kinship analysis that showed a potentially erroneous inclusion of paternal sisters between two women. The two women shared alleles at 18 X-chromosomal STR loci spanned from 14.76cM (DXS6807 to 184.19cM (DXS7423. When their relatives were not available for testing, biostatistical analysis for the 18 X-chromosomal STR loci and 24 autosomal STR loci revealed the most possible relationship between the two women was paternal sisters. However, when the father of one woman was available, the other father-daughter possibility was excluded. In the end, the likelihood ratio of STR marker and mitochondrial DNA (mtDNA sequences confirmed the two women were maternal sisters. This case emphasizes a cautionary interpretation of X chromosomal marker in deficiency paternity cases with female offspring. Even though large parts of the X-chromosome haplotypes shared by two females, additional relatives and extended DNA typing (such as mtDNA may be needed further to ascertain whether they are paternal or maternal sisters.

  3. ‘‘‘Sister to the tailor’: Guilds, gender and the needle trades in eighteenth-century Europe’

    DEFF Research Database (Denmark)

    Simonton, Deborah

    2017-01-01

    Milliners, and their sisters, mantuamakers, modistes and marchandes de mode, were skilled artisans, businesswomen and tradeswomen. During the eighteenth century, they commandeered the high-class sewing that set fashion and created stars of their most famous, like Rose Bertrand, milliner to Marie...

  4. Strand-seq : A unifying tool for studies of chromosome segregation

    NARCIS (Netherlands)

    Falconer, Ester; Lansdorp, Peter M.

    2013-01-01

    Non random segregation of sister chromatids has been implicated to help specify daughter cell fate (the Silent Sister Hypothesis [1]) or to protect the genome of long-lived stem cells (the Immortal Strand Hypothesis [2]). The idea that sister chromatids are non-randomly segregated into specific

  5. The Save our Sisters Project. A social network strategy for reaching rural black women.

    Science.gov (United States)

    Eng, E

    1993-08-01

    Why are older black women screened less for breast cancer? What can be done to narrow the racial gap in mammography screening? These are the questions addressed by the Save Our Sisters (SOS) Project, a pilot demonstration study funded by the National Cancer Institute in a rural county of North Carolina. The target population is 2600 black women 50-74 years of age residing in the county. To assist these women to obtain annual mammograms, SOS has recruited and trained 64 black women who are "natural helpers" to serve as lay health advisors. The lay health advisors reach older black women through their existing kin, friendship, and job networks. Responses from 14 focus group interviews found that when it is a matter of older black women's health concerns, women turn to certain women for social support. Responses revealed factors related to the individual woman and her social network that influence rural black women's seeking breast cancer screening. These results were applied to the Social Change model for designing the training and three network intervention strategies: (1) providing social support (information and referrals, emotional caring, and tangible assistance) through interpersonal counseling with women in their social networks; (2) working as a group, planning and implementing breast cancer control and prevention activities through community-based organizations to which advisors belong (e.g., church groups, civic groups, and social groups); and (3) establishing themselves as a non-profit, community-based SOS Association to sustain project interventions after the funding period. The SOS Community Advisory Group and the advisors developed innovative methods of recruitment, implementation, and follow-up. The community programs they have initiated are: (1) the Adopt-A-Sister Program, which assists black women who cannot afford the cost of a mammogram; (2) a committee on understanding the health care system, which assists women in negotiating regulations and

  6. Chromatin dynamics during cell cycle mediate conversion of DNA damage into chromatid breaks and affect formation of chromosomal aberrations: Biological and clinical significance

    Energy Technology Data Exchange (ETDEWEB)

    Terzoudi, Georgia I.; Hatzi, Vasiliki I. [Institute of Radioisotopes and Radiodiagnostic Products, National Centre for Scientific Research ' Demokritos' , 15310 Ag. Paraskevi Attikis, Athens (Greece); Donta-Bakoyianni, Catherine [Oral Diagnosis and Radiology, University of Athens Dental School, Athens (Greece); Pantelias, Gabriel E., E-mail: gabriel@ipta.demokritos.gr [Institute of Radioisotopes and Radiodiagnostic Products, National Centre for Scientific Research ' Demokritos' , 15310 Ag. Paraskevi Attikis, Athens (Greece)

    2011-06-03

    The formation of diverse chromosomal aberrations following irradiation and the variability in radiosensitivity at different cell-cycle stages remain a long standing controversy, probably because most of the studies have focused on elucidating the enzymatic mechanisms involved using simple DNA substrates. Yet, recognition, processing and repair of DNA damage occur within the nucleoprotein complex of chromatin which is dynamic in nature, capable of rapid unfolding, disassembling, assembling and refolding. The present work reviews experimental work designed to investigate the impact of chromatin dynamics and chromosome conformation changes during cell-cycle in the formation of chromosomal aberrations. Using conventional cytogenetics and premature chromosome condensation to visualize interphase chromatin, the data presented support the hypothesis that chromatin dynamic changes during cell-cycle are important determinants in the conversion of sub-microscopic DNA lesions into chromatid breaks. Consequently, the type and yield of radiation-induced chromosomal aberrations at a given cell-cycle-stage depends on the combined effect of DNA repair processes and chromatin dynamics, which is cell-cycle-regulated and subject to up- or down-regulation following radiation exposure or genetic alterations. This new hypothesis is used to explain the variability in radiosensitivity observed at various cell-cycle-stages, among mutant cells and cells of different origin, or among different individuals, and to revisit unresolved issues and unanswered questions. In addition, it is used to better understand hypersensitivity of AT cells and to provide an improved predictive G2-assay for evaluating radiosensitivity at individual level. Finally, experimental data at single cell level obtained using hybrid cells suggest that the proposed hypothesis applies only to the irradiated component of the hybrid.

  7. Effects of specialization on genetic differentiation in sister species of bark beetles.

    Science.gov (United States)

    Kelley, S T; Farrell, B D; Mitton, J B

    2000-02-01

    We investigated the relative importance of resource use and geography on genetic differentiation in the sister-species pair of generalist and specialist bark beetles: Dendroctonus ponderosae and D. jeffreyi (Coleoptera: Scolytidae). In two regions, where the distributions of these species overlap, we collected specimens of the generalist from multiple host species and specimens of the specialist from its single host species. Using allozyme techniques, we uncovered genetic differentiation between generalist populations on different host species in the same region (one locus in each region). However, a much stronger pattern of differentiation was found between specialist populations in the two distantly separated regions (three loci). With mtDNA, we found no significant differentiation between regions in the specialist, or among host species in the generalist, although there was some differentiation between regions in the generalist (AMOVA, P < 0.05). Overall, the generalist populations maintained approximately 10 times the genetic variation in mtDNA as the specialist populations, which suggests that the specialist either has generally smaller population sizes than the generalist, or has experienced a historical population bottleneck.

  8. Maxillary canine transpositions in two brothers and one sister: associated dental anomalies and genetic basis.

    Science.gov (United States)

    Segura, Juan J; Hattab, Faiez; Ríos, Vicente

    2002-01-01

    Transposition is an uncommon dental anomaly involving positional interchange of two teeth. The maxillary canine is the tooth more frequently transposed in man. Maxillary canine-first premolar appears to be the most common type of tooth transposition, followed by maxillary canine-lateral incisor transposition. Maxillary canine transpositions are frequently associated with other dental abnormalities such as agenesis and pegshaped incisors. This report describes the presence of transposed canines in one sister and two brothers. The female showed bilateral maxillary canine-first premolar transposition with the left canine fully mesial to its neighboring first premolar, and the right canine blocked-out facially between the first and second premolar. One of the brothers showed full maxillary left canine-lateral incisor transposition. The other brother showed maxillary canine-first premolar transposition and agenesis of maxillary lateral incisors, with the left canine blocked-out facially between the first and second premolar. Findings from this case report and other previously published cases provide strong evidence that maxillary canine transpositions are a disturbance of tooth order and eruptive position resulting from genetic influences within a multifactorial inheritance model.

  9. Sister Mary Joseph nodule as the presenting sign of disseminated prostate carcinoma

    Directory of Open Access Journals (Sweden)

    Deb Prabal

    2009-01-01

    Full Text Available Sister Mary Joseph′s nodule is referred to as metastasis of visceral malignancy to the umbilicus. Most common primaries are in the gastrointestinal or genital tract, while other locations are rare. We recently encountered a 76-year-old male who was referred to the surgery clinic with an erythematous nodule in the umbilicus measuring 6 cm in diameter with complaints of painless profuse hematuria. History revealed severe obstructive voiding symptoms of 2-year duration, along with significant loss of weight and difficulty in walking. A detailed examination showed hard nodular hepatomegaly, along with grade IV prostatomegaly. Serum prostate-specific antigen was 3069 ng/ml. A pelvic radiograph displayed multiple osteolytic lesions, while ultrasonography showed multiple iso- and hypoechoic lesions in both lobes of the liver, suggestive of metastasis. Histopathology of a Tru-cut biopsy of the prostate confirmed an adenocarcinoma (Gleason score 9 with umbilical metastasis. The patient was on regular follow-up and died 3 months later.

  10. Homozygous N396T mutation in Gaucher disease: Portuguese sisters with markedly different phenotypes

    Directory of Open Access Journals (Sweden)

    Samantha Kimball

    2011-03-01

    Full Text Available Samantha Kimball1,2, Francis Choy4, Agnes Zay5, Dominick Amato31Department of Nutritional Sciences, University of Toronto, Canada; 2Department of Laboratory Medicine and Pathology, 3Department of Medicine, Division of Hematology, Mt Sinai Hospital, Toronto, Canada; 4Department of Biology, University of Victoria, Victoria, Canada; 5MRC Center for Regenerative Medicine, University of Edinburgh, Edinburgh, ScotlandAbstract: Gaucher disease (GD is characterized by reduced activity of glucocerebrosidase leading to complications in the reticuloendothelial system. N396T, a rarer mutation of the glucocerebrosidase gene, has been encountered in Portuguese populations and has generally been associated with milder phenotypes. This report presents brief histories of two Portuguese sisters, both with homozygous N396T mutations. These patients are phenotypically very different despite the fact that in both patients residual enzyme activity is very low. The case of patient 1 is complicated by comorbid diabetes mellitus and human immunodeficiency virus (HIV infection. Enzyme replacement therapy (ERT improved this patient's clinical picture sufficiently to enable antiretroviral treatment to proceed for the HIV. This report demonstrates the poor correlation of clinical GD with genotype as well as with residual enzyme activity. It further illustrates how treatment of the underlying GD with ERT improved symptoms allowing for antiretroviral therapy thereby improving both the GD and HIV.Keywords: Gaucher disease, N396T mutation, glucocerebrosidase, HIV

  11. Homozygous Inactivating Mutation in NANOS3 in Two Sisters with Primary Ovarian Insufficiency

    Directory of Open Access Journals (Sweden)

    Mariza G. Santos

    2014-01-01

    Full Text Available Despite the increasing understanding of female reproduction, the molecular diagnosis of primary ovarian insufficiency (POI is seldom obtained. The RNA-binding protein NANOS3 poses as an interesting candidate gene for POI since members of the Nanos family have an evolutionarily conserved function in germ cell development and maintenance by repressing apoptosis. We performed mutational analysis of NANOS3 in a cohort of 85 Brazilian women with familial or isolated POI, presenting with primary or secondary amenorrhea, and in ethnically-matched control women. A homozygous p.Glu120Lys mutation in NANOS3 was identified in two sisters with primary amenorrhea. The substituted amino acid is located within the second C2HC motif in the conserved zinc finger domain of NANOS3 and in silico molecular modelling suggests destabilization of protein-RNA interaction. In vitro analyses of apoptosis through flow cytometry and confocal microscopy show that NANOS3 capacity to prevent apoptosis was impaired by this mutation. The identification of an inactivating missense mutation in NANOS3 suggests a mechanism for POI involving increased primordial germ cells (PGCs apoptosis during embryonic cell migration and highlights the importance of NANOS proteins in human ovarian biology.

  12. In the Time of the Butterflies: Rewriting Dominican History through the Demythologization of the Mirabal Sisters

    Directory of Open Access Journals (Sweden)

    Vansan Gonçalves

    2011-12-01

    Full Text Available This article intends to investigate the narration of historical facts under new perspectives through the novel In the Time of the Butterflies, from the Dominican-American writer Julia Alvarez. The choice of the mentioned novel is due to the fact that it enables the observation of the manners the concepts of identity, memory and representation interact to portray new representations of a determined people by the interpretation of historical facts. Throughout the article it will be analyzed the strategies Alvarez employs to narrate new versions of facts related to the period regarded as the “Trujillo era”, a totalitarian dictatorship which took place in the Dominican Republic between 1930 and 1961. It will be studied the process used by the author to promote the demythologization of the Mirabal sisters, martyrs of the struggle against the regime who, when launched to mythic status, were historically distanced from Dominicans. Post-colonial and postmodern concepts, as presented by theorists bell hooks, Priyamvada Gopal and Stuart Hall will be applied to the analysis of historical representation through the perspective of traditionally silenced groups. Linda Hutcheon’s definitions of “facts” and “events” will also be approached to observe the way the novel provides new readings of historical facts.

  13. Comparative transcriptome analysis of chemosensory genes in two sister leaf beetles provides insights into chemosensory speciation.

    Science.gov (United States)

    Zhang, Bin; Zhang, Wei; Nie, Rui-E; Li, Wen-Zhu; Segraves, Kari A; Yang, Xing-Ke; Xue, Huai-Jun

    2016-12-01

    Divergence in chemosensory traits has been posited as an important component of chemosensory speciation in insects. In particular, chemosensory genes expressed in the peripheral sensory neurons are likely to influence insect behaviors such as preference for food, oviposition sites, and mates. Despite their key role in insect behavior and potentially speciation, the underlying genetic basis for divergence in chemosensory traits remains largely unexplored. One way to ascertain the role of chemosensory genes in speciation is to make comparisons of these genes across closely related species to detect the genetic signatures of divergence. Here, we used high throughput transcriptome analysis to compare chemosensory genes of the sister leaf beetles species Pyrrhalta maculicollis and P. aenescens, whose sexual isolation and host plant preference are mediated by divergent chemical signals. Although there was low overall divergence between transcriptome profiles, there were a number of genes that were differentially expressed between the species. Furthermore, we also detected two chemosensory genes under positive selection, one of which that was also differentially expressed between the species, suggesting a possible role for these genes in chemical-based premating reproductive isolation and host use. Combined with the available chemical and ecological work in this system, further studies of the divergent chemosensory genes presented here will provide insight into the process of chemosensory speciation among Pyrrhalta beetles.

  14. Challenging stereotypes? The older woman in the TV series Brothers & Sisters.

    Science.gov (United States)

    Oró-Piqueras, Maricel

    2014-12-01

    The TV series, Brothers & Sisters, broadcast from 2006 to 2011 by ABC (USA) and a year later by Channel 4 (UK) with quite high audience rates, starts when the patriarchal figure, William Walker, dies of a heart attack and two female figures around their sixties come center stage: his wife, Nora Walker, and his long-term lover, Holly Harper. Once the patriarchal figure disappears, the female characters regain visibility by entering the labor market and starting relationships with other men. In that sense, both protagonists experience aging as a time in which they are increasingly freed from social and family constraints. However, their roles as nurturers keep on bringing them back to the domestic space in which they are safe from being involved in uncomfortable and unsuitable situations. Drawing on previous studies on the representation of the older woman in fictional media, this article intends to discern to what extent stereotypes related to the older woman are challenged through the two main protagonists of a contemporary TV series. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Fear and loathing in Mississippi: the attack on cAMP sister spirit.

    Science.gov (United States)

    Greene, Kate

    2003-01-01

    SUMMARY In 1993, the small rural community of Ovett, Miss., and a group of self-described radical lesbian feminists clashed over the establishment by the women of a feminist educational retreat known as Camp Sister Spirit. This dispute took the form of physical and psychological harassment of the women, wide-open public debate in the community, in the press, and on television, federal mediation efforts, and two lawsuits. This article analyzes this dispute using Mary Daly's seven patterns of the sado-ritual syndrome (Daly, 1978). The analysis examines the ideological and moral standpoints of the participants, the issues of "blaming the victim" and scapegoating, the development of the conflict from a dispute between neighbors to the involvement of international media, national activists and the Clinton Administration, the transformation of the conflict from a political to legal dispute, the representations of the groups within the community and the media, the effect of public opinion on the dispute, and the politics of the media in the dispute.

  16. On Sister Carrie from Feminist Perspective and its Influence on Chinese Modern Women

    Institute of Scientific and Technical Information of China (English)

    毛武毅; 叶青

    2013-01-01

    Sister Carrie is a famous naturalistic novelist-Theodore Dreiser’s first novel in the first 20th century. It tells a story of a young rural woman Carrie how to become the red Broadway actress from the bottom of society, and the story vividly depicts the survival state and psychological and ideological process of Carrie. When it was published, it attracted attentions of critics from domestic and abroad at large, and they researched it from different perspectives. But most of their researches discussed from the materialism angle to concern with the expression of Determinism and Darwinism. So far, few people made the research from the topic of Carrie’s pursuit of self-achievement and perspective of feminist. Actually, not only did Carrie restrict on the material pursuit, but also boldly in pursuit of the self-achievement of new women. This paper aims at Carrie how to pursue the self-achievement of new women, and the influence of feminist to Chinese modern women.

  17. Palaeopathological diagnosis after 2500 years. The case of Imakhetkherresnet, sister of priest Iufaa.

    Science.gov (United States)

    Strouhal, E; Nĕmecková, A

    2009-01-01

    The aim of palaeopathological studies has been traditionally the determination of a diagnosis of any found pathological change. If based merely on skeletal evidence, most of them proved to be only tentative. Our case of the mature female Imakhetkherresnet, sister of the lector-priest Iufaa, having preserved scraps of soft tissue, enabled a precise diagnosis. Her skeletized mummy was discovered in Iufaa's unmolested tomb dating late 26th Dynasty at Abusir (Egypt) by the Czech Institute of Egyptology in 2001. A large smooth-walled cavity moulded by pressure of a relatively hard, globular and lobulated tissue mass was found inside the sacrum, growing in hour-glass shape outside it. By macroscopic and radiographic examination its diagnosis was suggested, while by histological analysis with histochemical tests and comparison with a recent case, the origin of the hollow could be "clinically" determined. It was caused by a benign tumour, originating in the nerve sheath, called neurilemmoma (schwannoma, neurinoma). This kind of tumour, occurring in the sacrum relatively rarely, was never before described in the palaeopathological literature.

  18. Reproductive isolation between sympatric sister species, Mussaenda kwangtungensis and M. pubescens var. alba

    Institute of Scientific and Technical Information of China (English)

    Zhonglai Luo; Tingting Duan; Shuai Yuan; Shi Chen; Xiufeng Bai; Dianxiang Zhang

    2015-01-01

    Reproductive isolation defines the biological species concept and plays a key role in the formation and maintenance of species. The relative contributions of different isolating stages has been suggested to be closely associated with phylogenetic relatedness. Few studies have focused on the relative contributions of pre- versus post-zygotic mechanisms, and even fewer have been conducted under strict phylogenetic frameworks. Pre-and post-zygotic reproductive isolation stages have been investigated in the sister species Mussaenda kwangtungensis and M. pubescens var. alba. The two species have partly overlapping distribu-tion ranges and flowering times, while the principal pollinators differed strikingly for them, demonstrating strong pre-zygotic isolations. Natural hybrids were detected by simple sequence repeat markers and their maternal parents were identified based on chloroplast gene sequen-ces. Five out of 81 individuals were suggested to be hybrids that fall into the categories F2, BC1, and BC2 by the NewHybrids analysis. Interspecific crossings resulted in significantly reduced fruit set and seed germination rates. Phylogenetic analysis revealed short Kimura-2-parameter distance between M. kwangtungensis and M. pubescens var. alba. These findings strongly supported the hypothesis that for species with a closer phylogenetic relationship, pre-zygotic isolation plays an important part in limiting gene exchange in sympatric areas.

  19. Ringiculid bubble snails recovered as the sister group to sea slugs (Nudipleura)

    Science.gov (United States)

    Kano, Yasunori; Brenzinger, Bastian; Nützel, Alexander; Wilson, Nerida G.; Schrödl, Michael

    2016-08-01

    Euthyneuran gastropods represent one of the most diverse lineages in Mollusca (with over 30,000 species), play significant ecological roles in aquatic and terrestrial environments and affect many aspects of human life. However, our understanding of their evolutionary relationships remains incomplete due to missing data for key phylogenetic lineages. The present study integrates such a neglected, ancient snail family Ringiculidae into a molecular systematics of Euthyneura for the first time, and is supplemented by the first microanatomical data. Surprisingly, both molecular and morphological features present compelling evidence for the common ancestry of ringiculid snails with the highly dissimilar Nudipleura—the most species-rich and well-known taxon of sea slugs (nudibranchs and pleurobranchoids). A new taxon name Ringipleura is proposed here for these long-lost sisters, as one of three major euthyneuran clades with late Palaeozoic origins, along with Acteonacea (Acteonoidea + Rissoelloidea) and Tectipleura (Euopisthobranchia + Panpulmonata). The early Euthyneura are suggested to be at least temporary burrowers with a characteristic ‘bubble’ shell, hypertrophied foot and headshield as exemplified by many extant subtaxa with an infaunal mode of life, while the expansion of the mantle might have triggered the explosive Mesozoic radiation of the clade into diverse ecological niches.

  20. Pseudoxanthoma elasticum and reflectance confocal microscopy: report of two affected young sisters

    Directory of Open Access Journals (Sweden)

    Victor Desmond Mandel

    2015-04-01

    Full Text Available Pseudoxanthoma elasticum (PXE is a rare inherited multisystem disorder that mainly affects skin, eyes and cardiovascular system. The associated clinical signs are due to progressive calcification of elastic fibres and blood vessels, despite normal levels of calcium and phosphorus in blood and urine. The first clinical description of the disease was done in 1881 by Rigal, and in 1896 it was named PXE by Darier. Transmission of the disease is autosomal recessive. PXE is caused by homozygous or compound heterozygous mutations in the ATP-binding cassette subfamily C member 6 (ABCC6 gene, which encodes a transmembrane transport ADP-dependent protein (MRP6. The gene is expressed predominantly in the liver and kidney, and found in low level in the tissue involved by PXE. The clinical expression of PXE is heterogeneous with considerable variation in age of onset, progression and severity of the disease, even in individuals of the same family with identical mutations.We present the case of two young sisters affected by PXE and the correlation between the histopathology and the reflectance confocal microscopy (RCM. Parents and brother carry one copy of the mutated gene, without showing signs and symptoms of the disorder. We report the main clinical aspects of PXE and we highlight the importance of early diagnosis of the disease for adequate therapeutical management of associated complications.

  1. Pediatric familial neuromyelitis optica in two sisters with long term follow-up.

    Science.gov (United States)

    Chuquilin, Miguel; Mullaguri, Naresh; Weinshenker, Brian

    2016-07-01

    Neuromyelitis optica causes bilateral optic neuritis and longitudinal extensive transverse myelitis. Although usually sporadic, 3% of cases of neuromyelitis optica are familial. The interval over which attacks continue and the long term prognosis for pediatric-onset neuromyelitis optica are not well defined. We describe two patients with pediatric familial neuromyelitis optica with the longest clinical follow-up of a pediatric case reported in the literature to our knowledge. One woman developed blindness with bilateral eye involvement within a few weeks at age 3. This was followed by transverse myelitis with paraparesis at age 19 leading to diagnosis of neuromyelitis optica. Her serum anti-aquaporin 4 antibody was later found to be positive. She continued with sporadic myelitis-related relapses but remained ambulant until age 40 when she had a more severe relapse. There was evidence of longitudinal extensive T2 hyperintensity in the thoracic spinal cord. Her sister also developed blindness at age 3.5 followed by myelitis 1year later with multiple relapses of gait impairment until her death from pneumonia at age 21. These patients represent the rare occurrence of neuromyelitis optica in children within the same family and show that this disease can have prolonged periods of remission but a continued tendency to relapse, supporting the need for lifelong immunosuppression.

  2. The pheromones of laying workers in two honeybee sister species: Apis cerana and Apis mellifera.

    Science.gov (United States)

    Tan, Ken; Yang, Mingxian; Wang, Zhengwei; Radloff, Sarah E; Pirk, Christian W W

    2012-04-01

    When a honeybee colony loses its queen, workers activate their ovaries and begin to lay eggs. This is accompanied by a shift in their pheromonal bouquet, which becomes more queen like. Workers of the Asian hive bee Apis cerana show unusually high levels of ovary activation and this can be interpreted as evidence for a recent evolutionary arms race between queens and workers over worker reproduction in this species. To further explore this, we compared the rate of pheromonal bouquet change between two honeybee sister species of Apis cerana and Apis mellifera under queenright and queenless conditions. We show that in both species, the pheromonal components HOB, 9-ODA, HVA, 9-HDA, 10-HDAA and 10-HDA have significantly higher amounts in laying workers than in non-laying workers. In the queenright colonies of A. mellifera and A. cerana, the ratios (9-ODA)/(9-ODA + 9-HDA + 10-HDAA + 10-HDA) are not significantly different between the two species, but in queenless A. cerana colonies the ratio is significant higher than in A. mellifera, suggesting that in A. cerana, the workers' pheromonal bouquet is dominated by the queen compound, 9-ODA. The amount of 9-ODA in laying A. cerana workers increased by over 585% compared with the non-laying workers, that is 6.75 times higher than in A. mellifera where laying workers only had 86% more 9-ODA compared with non-laying workers.

  3. Comparison of similarity coefficients used for cluster analysis based on SSR markers in sister line wheat cultivars

    Directory of Open Access Journals (Sweden)

    Denčić Srbislav

    2016-01-01

    Full Text Available The objective of this study was to compared fourteen different similarity coefficients and their influence in sister line wheat cultivars clustering. Seventeen sister cultivars developed from two crosses were used and fingerprinted with 19 wheat microsatellite markers. Comparisons among the similarity coefficients were made using the Sperman correlation analysis, dendogram evaluation (visual inspection and consensus fork index - CIc, projection efficiency in a two-dimensional space, and groups formed by the Tocher optimization procedure. The Sperman correlation coefficients among the fourteen similarity coefficients were all high showing a strong association between them. The correlation coefficient between Dice and Kulczinski and Ochiai I as well as between Hamann and Simple matching and between Kulczinski and Ochiai I was equal to 1. Although visual estimation of the dendograms shows almost identical clustering structures, CIc indexes indicate that all coefficients are not identical. [Projekat Ministarstva nauke Republike Srbije, br. TR 31066

  4. An Analysis of Personal Factors that Determine Carrie’s Self -Actual-ization in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    YU Shuang-shuang

    2014-01-01

    In Dreiser’s novel Sister Carrie, the heroine Carrie’s self-actualizing natures are reflected in her self-actualization ef-fort. Those natures include the acceptance of reality and potential to be actress, etc., which play the crucial role of her star jour-ney and self-actualizing effort. Therefore, every woman should have the spiritual spirit;and, at the same time, pursue nobler spiri-tual life.

  5. {beta} -carotene effect the induction of the sister chromatid exchanges (ICH) by gamma radiation in mouse radiosensibilized osseous marrow cells In vivo; Efecto del {beta}- caroteno la induccion de intercambios en las cromatidas hermanas (ICH) por radiacion gamma en celulas radiosensibilizadas de la medula osea de raton In vivo

    Energy Technology Data Exchange (ETDEWEB)

    Morales R, P.; Cruz V, V.L. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico). Dept. de Biologia

    1997-07-01

    The effect of {beta}- carotene over the ICH radioinduction in radiosensibilized with BrdU osseous marrow cells of mouse was determined In vivo. The treatment with 50 {mu}g {beta} carotene per se induces a significant increment in the ICH frequency and the pre or post-treatment with the same dose causes an additive effect in the ICH frequency produced by 0.62 Gy of gamma radiation. This implies that {beta}- carotene does not have radioprotective activity, under conditions which was developed this experiment. (Author)

  6. The relationship of psychosocial factors to mammograms, physical activity, and fruit and vegetable consumption among sisters of breast cancer patients.

    Science.gov (United States)

    Hartman, Sheri J; Dunsiger, Shira I; Jacobsen, Paul B

    2011-01-01

    This study examined the relationship of psychosocial factors to health-promoting behaviors in sisters of breast cancer patients. One hundred and twenty sisters of breast cancer patients completed questionnaires assessing response efficacy of mammography screenings, physical activity, and fruit and vegetable consumption on decreasing breast cancer risk, breast cancer worry, involvement in their sister's cancer care, mammography screenings, physical activity, and fruit and vegetable consumption. Results indicate that greater perceived effectiveness for mammograms was associated with a 67% increase in odds of yearly mammograms. Greater involvement in the patient's care was associated with a 7% decrease in odds of yearly mammograms. Greater perceived effectiveness for physical activity was significantly related to greater physical activity. There was a trend for greater perceived effectiveness for fruits and vegetables to be associated with consuming more fruits and vegetables. Breast cancer worry was not significantly associated with the outcomes. While perceived effectiveness for a specific health behavior in reducing breast cancer risk was consistently related to engaging in that health behavior, women reported significantly lower perceived effectiveness for physical activity and fruits and vegetables than for mammograms. Making women aware of the health benefits of these behaviors may be important in promoting changes.

  7. Reproductive isolation and ecological niche partition among larvae of the morphologically cryptic sister species Chironomus riparius and C. piger.

    Directory of Open Access Journals (Sweden)

    Markus Pfenninger

    Full Text Available BACKGROUND: One of the central issues in ecology is the question what allows sympatric occurrence of closely related species in the same general area? The non-biting midges Chironomus riparius and C. piger, interbreeding in the laboratory, have been shown to coexist frequently despite of their close relatedness, similar ecology and high morphological similarity. METHODOLOGY/PRINCIPAL FINDINGS: In order to investigate factors shaping niche partitioning of these cryptic sister species, we explored the actual degree of reproductive isolation in the field. Congruent results from nuclear microsatellite and mitochondrial haplotype analyses indicated complete absence of interspecific gene-flow. Autocorrelation analysis showed a non-random spatial distribution of the two species. Though not dispersal limited at the scale of the study area, the sister species occurred less often than expected at the same site, indicating past or present competition. Correlation and multiple regression analyses suggested the repartition of the available habitat along water chemistry gradients (nitrite, conductivity, CaCO(3, ultimately governed by differences in summer precipitation regime. CONCLUSIONS: We show that these morphologically cryptic sister species partition their niches due to a certain degree of ecological distinctness and total reproductive isolation in the field. The coexistence of these species provides a suitable model system for the investigation of factors shaping the distribution of closely related, cryptic species.

  8. Design principles of the sparse coding network and the role of sister cells in the olfactory system of Drosophila

    Directory of Open Access Journals (Sweden)

    Danke eZhang

    2013-10-01

    Full Text Available Sensory systems face the challenge to represent sensory inputs in a way to allow easy readout of sensory information by higher brain areas. In the olfactory system of the fly drosopohila melanogaster, projection neurons (PNs of the antennal lobe (AL convert a dense activation of glomeruli into a sparse, high-dimensional firing pattern of Kenyon cells (KCs in the mushroom body (MB. Here we investigate the design principles of the olfactory system of drosophila in regard to the capabilities to discriminate odor quality from the MB representation and its robustness to different types of noise. We focus on understanding the role of highly correlated homotypic projection neurons (sister cells found in the glomeruli of flies. These cells are coupled by gap-junctions and receive almost identical sensory inputs, but target randomly different KCs in MB. We show that sister cells might play a crucial role in increasing the robustness of the MB odor representation to noise. Computationally, sister cells thus might help the system to improve the generalization capabilities in face of noise without impairing the discriminability of odor quality at the same time.

  9. Transcriptome Profiling Reveals Auxin and Cytokinin Regulating Somatic Embryogenesis in Different Sister Lines of Cotton Cultivar CCR124

    Institute of Scientific and Technical Information of China (English)

    Zhenzhen Xu; Chaojun Zhang; Xueyan Zhang; Chuanliang Liu; Zhixia Wu; Zuoren Yang; Kehai Zhou

    2013-01-01

    To get a broader view on the molecular mechanisms underlying somatic embryogenesis (SE) in cotton (Gossypium hirsutum L.),global analysis of cotton transcriptome dynamics during SE in different sister lines was performed using RNA-Seq.A total of 204 349 unigenes were detected by de novo assembly of the 214 977 462 Illumina reads.The quantitative reverse transcription-polymerase chain reaction (qRT-PCR) measurements were positively correlated with the RNA-Seq results for almost all the tested genes (R2 =0.841,correlation was significant at the 0.01 level).Different phytohormone (auxin and cytokinin) concentration ratios in medium and the endogenous content changes of these two phytohormones at two stages in different sister lines suggested the roles of auxin and cytokinin during cotton SE.On the basis of global gene regulation of phytohormone-related genes,numerous genes from all the differentially expressed transcripts were involved in auxin and cytokinin biosynthesis and signal transduction pathways.Analyses of differentially expressed genes that were involved in these pathways revealed the substantial changes in gene type and abundance between two sister lines.Isolation,cloning and silencing/ overexpressing the genes that revealed remarkable up-or down-expression during cotton SE were important.Furthermore,auxin and cytokinin play a primary role in SE,but potential cross-talk with each other or other factors remains unclear.

  10. Strategy for Fuel Rod Receipt, Characterization, Sample Allocation for the Demonstration Sister Rods

    Energy Technology Data Exchange (ETDEWEB)

    Marschman, Steven C. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Warmann, Stephan A. [Portage, Inc., Idaho Falls, ID (United States); Rusch, Chris [NAC International, Inc., Norcross, GA (United States)

    2014-03-01

    , inert gas backfilling, and transfer to an Independent Spent Fuel Storage Installation (ISFSI) for multi-year storage. To document the initial condition of the used fuel prior to emplacement in a storage system, “sister ” fuel rods will be harvested and sent to a national laboratory for characterization and archival purposes. This report supports the demonstration by describing how sister rods will be shipped and received at a national laboratory, and recommending basic nondestructive and destructive analyses to assure the fuel rods are adequately characterized for UFDC work. For this report, a hub-and-spoke model is proposed, with one location serving as the hub for fuel rod receipt and characterization. In this model, fuel and/or clad would be sent to other locations when capabilities at the hub were inadequate or nonexistent. This model has been proposed to reduce DOE-NE’s obligation for waste cleanup and decontamination of equipment.

  11. The Face of the Earth and those of her sisters: why are they so different?

    Science.gov (United States)

    Celal Sengor, A. M.

    2014-05-01

    The terrestrial planets, Mercury (uncompressed density: 5.3 g/cm3) Venus (4.4), the earth (4.4), and Mars 3.8) and the Moon, the rocky satellite of the earth (3.3), have formed some 4500 to 4600 million years ago through gravitational accretion about individual centres of attraction around the Sun. Yet all five have very different "faces" to use Eduard Suess' happy expression (adopted by Alfred Wegener for the Moon also). The earth looks blue when viewed from space because of Rayleigh scattering in its atmosphere. Venus looks yellowish due to its clouds of sulfuric acid and Mars is buff because of its dusty atmosphere. The earth's hypsometric curve is double-peaked; Mars' approaches the earth's. The others have single-peaked curves. Mercury and the Moon are very similar-looking, but this is deceptive: we now recognise that Mercury has extensive thrust faulting resulting from planetary contraction; the Moon probably has contractional structures, but on an incomparably smaller scale. Venus has an active interior albeit incapable of dividing its surface into horizontally-moving plates. Mars has a less active interior, but it seems nevertheless active with volcanism as recently as 2 Ma ago. Venus and Mars have plume-dominated tectonics. The earth gets its heat out by plate tectonics (but also by plumes) creating its most distinctive facial features: the orogenic belts and the oceans. The differences among the sisters seem to be due to distance from the sun, accretion history and final size. So far, the most thrilling results concerning their geology have been gained as soon as we obtained the capability of looking at their faces and knock on their rocks.

  12. Comparative Postembryonic Skeletal Ontogeny in Two Sister Lineages of Old World Tree Frogs (Rhacophoridae: Taruga, Polypedates)

    Science.gov (United States)

    Senevirathne, Gayani; Kerney, Ryan

    2017-01-01

    Rhacophoridae, a family of morphologically cryptic frogs, with many genetically distinct evolutionary lineages, is understudied with respect to skeletal morphology, life history traits and skeletal ontogeny. Here we analyze two species each from two sister lineages, Taruga and Polypedates, and compare their postembryonic skeletal ontogeny, larval chondrocrania and adult osteology in the context of a well-resolved phylogeny. We further compare these ontogenetic traits with the direct-developing Pseudophilautus silus. For each species, we differentially stained a nearly complete developmental series of tadpoles from early postembryonic stages through metamorphosis to determine the intraspecific and interspecific differences of cranial and postcranial bones. Chondrocrania of the four species differ in 1) size; 2) presence/absence of anterolateral and posterior process; and 3) shape of the suprarostral cartilages. Interspecific variation of ossification sequences is limited during early stages, but conspicuous during later development. Early cranial ossification is typical of other anuran larvae, where the frontoparietal, exoccipital and parasphenoid ossify first. The ossification sequences of the cranial bones vary considerably within the four species. Both species of Taruga show a faster cranial ossification rate than Polypedates. Seven cranial bones form when larvae near metamorphic climax. Ossification of all 18 cranial bones is initiated by larval Gosner stage 46 in T. eques. However, some cranial bone formation is not initiated until after metamorphosis in the other three species. Postcranial sequence does not vary significantly. The comparison of adult osteology highlights two characters, which have not been previously recorded: presence/absence of the parieto-squamosal plates and bifurcated base of the omosternum. This study will provide a starting point for comparative analyses of rhacophorid skeletal ontogeny and facilitate the study of the evolution of

  13. Karyotype variability in tropical maize sister inbred lines and hybrids compared with KYS standard line.

    Science.gov (United States)

    Mondin, Mateus; Santos-Serejo, Janay A; Bertäo, Mônica R; Laborda, Prianda; Pizzaia, Daniel; Aguiar-Perecin, Margarida L R

    2014-01-01

    Maize karyotype variability has been extensively investigated. The identification of maize somatic and pachytene chromosomes has improved with the development of fluorescence in situ hybridization (FISH) using tandemly repeated DNA sequences as probes. We identified the somatic chromosomes of sister inbred lines that were derived from a tropical flint maize population (Jac Duro [JD]), and hybrids between them, using FISH probes for the 180-bp knob repeat, centromeric satellite (CentC), centromeric satellite 4 (Cent4), subtelomeric clone 4-12-1, 5S ribosomal DNA and nucleolus organizing region DNA sequences. The observations were integrated with data based on C-banded mitotic metaphases and conventional analysis of pachytene chromosomes. Heterochromatic knobs visible at pachynema were coincident with C-bands and 180-bp FISH signals on somatic chromosomes, and most of them were large. Variation in the presence of some knobs was observed among lines. Small 180-bp knob signals were invariant on the short arms of chromosomes 1, 6, and 9. The subtelomeric 4-12-1 signal was also invariant and useful for identifying some chromosomes. The centromere location of chromosomes 2 and 4 differed from previous reports on standard maize lines. Somatic chromosomes of a JD line and the commonly used KYS line were compared by FISH in a hybrid of these lines. The pairing behavior of chromosomes 2 and 4 at pachytene stage in this hybrid was investigated using FISH with chromosome-specific probes. The homologues were fully synapsed, including the 5S rDNA and CentC sites on chromosome 2, and Cent4 and subtelomeric 4-12-1 sites on chromosome 4. This suggests that homologous chromosomes could pair through differential degrees of chromatin packaging in homologous arms differing in size. The results contribute to current knowledge of maize global diversity and also raise questions concerning the meiotic pairing of homologous chromosomes possibly differing in their amounts of repetitive DNA.

  14. A comparison of leaf crystal macropatterns in the two sister genera Piper and Peperomia (Piperaceae).

    Science.gov (United States)

    Horner, Harry T; Wanke, Stefan; Samain, Marie-Stéphanie

    2012-06-01

    This is the first large-scale study comparing leaf crystal macropatterns of the species-rich sister genera Piper and Peperomia. It focuses on identifying types of calcium oxalate crystals and their macropatterns in leaves of both genera. The Piper results are placed in a phylogenetic context to show evolutionary patterns. This information will expand knowledge about crystals and provide specific examples to help study their form and function. One example is the first-time observation of Piper crystal sand tumbling in chlorenchyma vacuoles. Herbarium and fresh leaves were cleared of cytoplasmic content and examined with polarizing microscopy to identify types of crystals and their macropatterns. Selected hydrated herbarium and fresh leaf punches were processed for scanning electron microscopy and x-ray elemental analysis. Vibratome sections of living Piper and Peperomia leaves were observed for anatomical features and crystal movement. Both genera have different leaf anatomies. Piper displays four crystal types in chlorenchyma-crystal sand, raphides, styloids, and druses, whereas Peperomia displays three types-druses, raphides, and prisms. Because of different leaf anatomies and crystal types between the genera, macropatterns are completely different. Crystal macropattern evolution in both is characterized by increasing complexity, and both may use their crystals for light gathering and reflection for efficient photosynthesis under low-intensity light environments. Both genera have different leaf anatomies, types of crystals and crystal macropatterns. Based on Piper crystals associated with photosynthetic tissues and low-intensity light, further study of their function and association with surrounding chloroplasts is warranted, especially active crystal movement.

  15. Associations among personal care product use patterns and exogenous hormone use in the NIEHS Sister Study.

    Science.gov (United States)

    Taylor, Kyla W; Baird, Donna D; Herring, Amy H; Engel, Lawrence S; Nichols, Hazel B; Sandler, Dale P; Troester, Melissa A

    2017-09-01

    It is hypothesized that certain chemicals in personal care products may alter the risk of adverse health outcomes. The primary aim of this study was to use a data-centered approach to classify complex patterns of exposure to personal care products and to understand how these patterns vary according to use of exogenous hormone exposures, oral contraceptives (OCs) and post-menopausal hormone therapy (HT). The NIEHS Sister Study is a prospective cohort study of 50,884 US women. Limiting the sample to non-Hispanic blacks and whites (N=47,019), latent class analysis (LCA) was used to identify groups of individuals with similar patterns of personal care product use based on responses to 48 survey questions. Personal care products were categorized into three product types (beauty, hair, and skincare products) and separate latent classes were constructed for each type. Adjusted prevalence differences (PD) were calculated to estimate the association between exogenous hormone use, as measured by ever/never OC or HT use, and patterns of personal care product use. LCA reduced data dimensionality by grouping of individuals with similar patterns of personal care product use into mutually exclusive latent classes (three latent classes for beauty product use, three for hair, and four for skin care. There were strong differences in personal care usage by race, particularly for haircare products. For both blacks and whites, exogenous hormone exposures were associated with higher levels of product use, especially beauty and skincare products. Relative to individual product use questions, latent class variables capture complex patterns of personal care product usage. These patterns differed by race and were associated with ever OC and HT use. Future studies should consider personal care product exposures with other exogenous exposures when modeling health risks.

  16. Kinematic, finite strain and vorticity analysis of the Sisters Shear Zone, Stewart Island, New Zealand

    Science.gov (United States)

    Ring, Uwe; Bernet, Matthias; Tulloch, Andy

    2015-04-01

    The Sisters Shear Zone (SSZ) on Stewart Island, New Zealand, is a greenschist-facies extensional shear zone active prior to and possibly during the development of the Pacific-Antarctica spreading ridge at ˜76 Ma. We report quantitative kinematic and rotation data as well as apatite fission-track (AFT) ages from the SSZ. Early kinematic indicators associated with the NNE-trending stretching lineation formed under upper greenschist-facies metamorphism and show alternating top-to-the-NNW and top-to-the-SSE senses of shear. During progressive exhumation lowermost greenschist-facies and brittle-ductile kinematic indicators depict a more uniform top-to-the-SSE sense of shear in the topmost SSZ just below the detachment plane. Deformed metagranites in the SSZ allow the reconstruction of deformation and flow parameters. The mean kinematic vorticity number (Wm) ranges from 0.10 to 0.89; smaller numbers prevail in the deeper parts of the shear zone with a higher degree of simple shear deformation in the upper parts of the shear zone (deeper and upper parts relate to present geometry). High finite strain intensity correlates with low Wm and high Wm numbers near the detachment correlate with relatively weak strain intensity. Finite strain shows oblate geometries. Overall, our data indicate vertical and possibly temporal variations in deformation of the SSZ. Most AFT ages cluster around 85-75 Ma. We interpret the AFT ages to reflect the final stages of continental break-up just before and possibly during the initiation of sea-floor spreading between New Zealand and Antarctica.

  17. [Narrative report for Ottawa National Wildlife Refuge, Cedar Point National Wildlife Refuge, West Sister Island National Wildlife Refuge, Navarre Tract: Calendar year 1966

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa, Cedar Point, and West Sister Island National Wildlife Refuges outlines Refuge accomplishments during the 1966 calendar year....

  18. Amid the Pointing and the Horror beyond the Clean Flame——On Quentin's Confession of Incest with His Sister Caddy in The Sound and the Fury

    Institute of Scientific and Technical Information of China (English)

    尹宇

    2007-01-01

    The connotation of "incest" in Quentin's narration goes beyond what Faulkner would admit.It reflects not only the complex relationship between Quentin and his sister Caddy, but also the angst the protagonist feels in pursuit of infinitude.

  19. [Narrative report for Ottawa National Wildlife Refuge, Cedar Point National Wildlife Refuge, West Sister Island National Wildlife Refuge, Navarre Tract: Calendar year 1970

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa, Cedar Point, and West Sister Island National Wildlife Refuges outlines Refuge accomplishments during the 1970 calendar year....

  20. [Narrative report for Ottawa National Wildlife Refuge, Cedar Point National Wildlife Refuge, West Sister Island National Wildlife Refuge, Navarre Tract: Calendar year 1967

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa, Cedar Point, and West Sister Island National Wildlife Refuges outlines Refuge accomplishments during the 1967 calendar year....

  1. Pike and salmon as sister taxa: detailed intraclade resolution and divergence time estimation of Esociformes + Salmoniformes based on whole mitochondrial genome sequences.

    Science.gov (United States)

    Campbell, Matthew A; López, J Andrés; Sado, Tetsuya; Miya, Masaki

    2013-11-01

    The increasing number of taxa and loci in molecular phylogenetic studies of basal euteleosts has brought stability in a controversial area. A key emerging aspect to these studies is a sister Esociformes (pike) and Salmoniformes (salmon) relationship. We evaluate mitochondrial genome support for a sister Esociformes and Salmoniformes hypothesis by surveying many potential outgroups for these taxa, employing multiple phylogenetic approaches, and utilizing a thorough sampling scheme. Secondly, we conduct a simultaneous divergence time estimation and phylogenetic inference in a Bayesian framework with fossil calibrations focusing on relationships within Esociformes+Salmoniformes. Our dataset supports a sister relationship between Esociformes and Salmoniformes; however the nearest relatives of Esociformes+Salmoniformes are inconsistent among analyses. Within the order Esociformes, we advocate for a single family, Esocidae. Subfamily relationships within Salmonidae are poorly supported as Salmoninae sister to Thymallinae+Coregoninae.

  2. [Narrative report for Ottawa National Wildlife Refuge, Cedar Point National Wildlife Refuge, West Sister Island National Wildlife Refuge, Navarre Tract: Calendar year 1968

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ottawa, Cedar Point, and West Sister Island National Wildlife Refuges outlines Refuge accomplishments during the 1968 calendar year....

  3. Geodetic observations and modeling of magmatic inflation at the Three Sisters volcanic center, central Oregon Cascade Range, USA

    Science.gov (United States)

    Dzurisin, Daniel; Lisowski, Michael; Wicks, Charles W.; Poland, Michael P.; Endo, Elliot T.

    2006-01-01

    Tumescence at the Three Sisters volcanic center began sometime between summer 1996 and summer 1998 and was discovered in April 2001 using interferometric synthetic aperture radar (InSAR). Swelling is centered about 5 km west of the summit of South Sister, a composite basaltic-andesite to rhyolite volcano that last erupted between 2200 and 2000 yr ago, and it affects an area ∼20 km in diameter within the Three Sisters Wilderness. Yearly InSAR observations show that the average maximum displacement rate was 3–5 cm/yr through summer 2001, and the velocity of a continuous GPS station within the deforming area was essentially constant from June 2001 to June 2004. The background level of seismic activity has been low, suggesting that temperatures in the source region are high enough or the strain rate has been low enough to favor plastic deformation over brittle failure. A swarm of about 300 small earthquakes (Mmax = 1.9) in the northeast quadrant of the deforming area on March 23–26, 2004, was the first notable seismicity in the area for at least two decades. The U.S. Geological Survey (USGS) established tilt-leveling and EDM networks at South Sister in 1985–1986, resurveyed them in 2001, the latter with GPS, and extended them to cover more of the deforming area. The 2001 tilt-leveling results are consistent with the inference drawn from InSAR that the current deformation episode did not start before 1996, i.e., the amount of deformation during 1995–2001 from InSAR fully accounts for the net tilt at South Sister during 1985–2001 from tilt-leveling. Subsequent InSAR, GPS, and leveling observations constrain the source location, geometry, and inflation rate as a function of time. A best-fit source model derived from simultaneous inversion of all three datasets is a dipping sill located 6.5 ± 2.5 km below the surface with a volume increase of 5.0 × 106 ± 1.5 × 106m3/yr (95% confidence limits). The most likely cause of tumescence is a pulse of

  4. [Nutritional status of two generations of brothers and sisters <5 years of age beneficiaries from opportunities living in marginalized rural communities in Chiapas, Mexico].

    Science.gov (United States)

    García-Parra, Esmeralda; Ochoa-Díaz-López, Héctor; García-Miranda, Rosario; Moreno-Altamirano, Laura; Morales, Helda; Estrada-Lugo, Erin Ingrid Jane; Solís-Hernández, Roberto

    2015-06-01

    Mexico, in recent decades, has developed several programs to eradicate the problem of infant malnutrition Oportunidades beneficiaries. Cross-sectional study. It was determined: underweight, stunting, wasting and overweight plus obesity. Older brothers and sisters were evaluated in 2002-2003, for 2010-2011 younger brothers and sisters were evaluated, both groups were <5 years of age at the time of data collection. Malnutrition, in its three types is a problem. 43.4% of brothers and sisters evaluated in 2010-2011 showed stunting, underweight prevalence declined from 18% to 13.2%, wasting (low weight for height) increased from 8.1% to 10.4%. Overweight and obesity increased significantly by 12 percentage points among brothers and sisters, from 24.8% in 2002-2003 to 36.8% in 2010-2011. Malnutrition among male children is lower than their brothers and sisters from the 2002-2003 generation (stunting p=<0.05), overweight and obesity was 10.9 percentage points higher than their brothers and sisters (26.4% to 37.3%). Children beneficiaries from Opportunities have not yet overcome chronic malnutrition problems. This study shows that there is not a clear impact in improving the nutritional status of the study population. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  5. Irmã Tereza Notarnicola Sor Tereza Notarnicola Sister Tereza Notarnicola

    Directory of Open Access Journals (Sweden)

    Taka Oguisso

    2006-12-01

    ó con todas las líderes de enfermería y pioneras del país, organizando congresos, conferencias y otros eventos científicos. Todos los enfermeros están en débito con esta notable figura de enfermería, quien en sus 86 años, sigue trabajando en una casa de personas de edad. Ella es una legenda viva y modelo para los enfermeros jóvenes.This paper aims at identifying the motivations which moved Sister Tereza toward nursing and her insertion into Brazilian Nursing Association contributing to disseminate her history as an example of professional life and dedication to nursing. This is a social-historical study based on historical-methodological reference approach of Oral History of Life for data collection. Sister Tereza worked over 33 years for the benefit of all nurses. During this period she contributed to build up the national headquarter of the Association, in Brasília, not only collecting resources through several raising funds campaigns, but also administering the construction itself. She also was executive secretary of the Association for many years and worked with all main nurse-leaders and pioneers of the country, organizing national congresses, conferences and other scientific events. All nurses are in debt to this notable nursing figure, who at the age of 86, continues working in a nursing home caring old people. She is a living legend and model for young nurses.

  6. Phylogenetic Analysis of Seven WRKY Genes across the Palm Subtribe Attaleinae (Arecaceae) Identifies Syagrus as Sister Group of the Coconut

    Science.gov (United States)

    Meerow, Alan W.; Noblick, Larry; Borrone, James W.; Couvreur, Thomas L. P.; Mauro-Herrera, Margarita; Hahn, William J.; Kuhn, David N.; Nakamura, Kyoko; Oleas, Nora H.; Schnell, Raymond J.

    2009-01-01

    Background The Cocoseae is one of 13 tribes of Arecaceae subfam. Arecoideae, and contains a number of palms with significant economic importance, including the monotypic and pantropical Cocos nucifera L., the coconut, the origins of which have been one of the “abominable mysteries” of palm systematics for decades. Previous studies with predominantly plastid genes weakly supported American ancestry for the coconut but ambiguous sister relationships. In this paper, we use multiple single copy nuclear loci to address the phylogeny of the Cocoseae subtribe Attaleinae, and resolve the closest extant relative of the coconut. Methodology/Principal Findings We present the results of combined analysis of DNA sequences of seven WRKY transcription factor loci across 72 samples of Arecaceae tribe Cocoseae subtribe Attaleinae, representing all genera classified within the subtribe, and three outgroup taxa with maximum parsimony, maximum likelihood, and Bayesian approaches, producing highly congruent and well-resolved trees that robustly identify the genus Syagrus as sister to Cocos and resolve novel and well-supported relationships among the other genera of the Attaleinae. We also address incongruence among the gene trees with gene tree reconciliation analysis, and assign estimated ages to the nodes of our tree. Conclusions/Significance This study represents the as yet most extensive phylogenetic analyses of Cocoseae subtribe Attaleinae. We present a well-resolved and supported phylogeny of the subtribe that robustly indicates a sister relationship between Cocos and Syagrus. This is not only of biogeographic interest, but will also open fruitful avenues of inquiry regarding evolution of functional genes useful for crop improvement. Establishment of two major clades of American Attaleinae occurred in the Oligocene (ca. 37 MYBP) in Eastern Brazil. The divergence of Cocos from Syagrus is estimated at 35 MYBP. The biogeographic and morphological congruence that we see for

  7. Emplacement of Holocene silicic lava flows and domes at Newberry, South Sister, and Medicine Lake volcanoes, California and Oregon

    Science.gov (United States)

    Fink, Jonathan H.; Anderson, Steven W.

    2017-07-19

    This field guide for the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) Scientific Assembly 2017 focuses on Holocene glassy silicic lava flows and domes on three volcanoes in the Cascade Range in Oregon and California: Newberry, South Sister, and Medicine Lake volcanoes. Although obsidian-rich lava flows have been of interest to geologists, archaeologists, pumice miners, and rock hounds for more than a century, many of their emplacement characteristics had not been scientifically observed until two very recent eruptions in Chile. Even with the new observations, several eruptive processes discussed in this field trip guide can only be inferred from their final products. This makes for lively debates at outcrops, just as there have been in the literature for the past 30 years.Of the three volcanoes discussed in this field guide, one (South Sister) lies along the main axis defined by major peaks of the Cascade Range, whereas the other two lie in extensional tectonic settings east of the axis. These two tectonic environments influence volcano morphology and the magmatic and volcanic processes that form silicic lava flows and domes. The geomorphic and textural features of glass-rich extrusions provide many clues about their emplacement and the magma bodies that fed them.The scope of this field guide does not include a full geologic history or comprehensive explanation of hazards associated with a particular volcano or volcanic field. The geochemistry, petrology, tectonics, and eruption history of Newberry, South Sister, and Medicine Lake volcanic centers have been extensively studied and are discussed on other field excursions. Instead, we seek to explore the structural, textural, and geochemical evolution of well-preserved individual lava flows—the goal is to understand the geologic processes, rather than the development, of a specific volcano.

  8. Regulation of mitotic progression by the spindle assembly checkpoint

    DEFF Research Database (Denmark)

    Lischetti, Tiziana; Nilsson, Jakob

    2015-01-01

    Equal segregation of sister chromatids during mitosis requires that pairs of kinetochores establish proper attachment to microtubules emanating from opposite poles of the mitotic spindle. The spindle assembly checkpoint (SAC) protects against errors in segregation by delaying sister separation...

  9. [Detection of sister chromatic exchange in workers exposed to coal tar pitch and to coke oven volatiles].

    Science.gov (United States)

    Wang, X; Chen, C; Wu, Y; Xu, Y

    1998-07-01

    In order to know the changes of genetic toxicological effects on workers occupationally exposed to polycyclic aromatic hydrocarbons (PAHs), sister chromatic exchange(SCE) was detected by the methods of peripheral lymphocyte culture in 23 workers exposed to coal tar pitch (CTP) and in 19 workers exposed to coke oven volatiles (COV) and 12 normal controls. The results suggested that the SCE in occupational workers was significantly higher than that in controls (11.31 vs 6.37, P 0.05). It is indicated that CTP and COV caused strong genetic toxicity and injury to chromosome.

  10. Sister mary joseph′s nodule: A case of umbilical cutaneous metastasis with signet ring cell histology

    Directory of Open Access Journals (Sweden)

    Zadeh Valid

    2009-01-01

    Full Text Available The metastasis of a visceral malignancy to the umbilicus is known as "Sister Mary Joseph′s nodule". It is a rare clinical sign indicating advanced, metastasizing intraabdominal cancer. We report a 50-year-old man who developed metastatic skin cancer in the form of semicircular indurated plaque on top of which was a firm mobile rounded nodule at the umbilical area. Histopathological examination demonstrated diastase-resistant periodic acid-Schiff and mucicarmine positive signet ring cells, suggesting gastric carcinoma. Immunohistochemical staining showed that these cells were positive for cytokeratins and epithelial membrane antigen, suggesting epithelial origin.

  11. Sister Mary Joseph's nodule as the first sign of pregnancy-associated gastric cancer:A case report

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Sister Mary.Joseph's nodule is an inconspicuous and uncommon clinical sign of advanced malignant disease,especially gastric cancer.Pregnancy-associated gastric cancer is an extremely rare condition and can be difficult to diagnose,due to the absence or misinterpretation of symptoms as pregnancy-related.Diagnostic aids,such as a basic chernisJTy panel and imaging techniques,may not show any abnonnalities.We present a case of a 37-yearold pregnant patient whose umbilical nodule was the first preserfdng physical sign of gastric cancer,which had metastasized throughout the abdominal and pelvic regions.

  12. All in the family: evaluation of the process and content of sisters' communication about BRCA1 and BRCA2 genetic test results.

    Science.gov (United States)

    Hughes, Chanita; Lerman, Caryn; Schwartz, Marc; Peshkin, Beth N; Wenzel, Lari; Narod, Steven; Corio, Camille; Tercyak, Kenneth P; Hanna, Danielle; Isaacs, Claudine; Main, David

    2002-01-15

    Despite the potential importance of family communication, little is known about the process and content of communicating BRCA1/2 test results to relatives. The objectives of this observational study were to describe the process and content of communicating BRCA1/2 test results to sisters, and to evaluate whether the proband's carrier status influenced communication outcomes. Participants were 43 women who were the first family member to have genetic testing (probands). Probands reported on communication outcomes for 81 sisters. Process and content variables were evaluated 1-month after receipt of BRCA1/2 test results using the Family Communication Questionnaire (FCQ). Overall, BRCA1/2 test results were communicated to 85% of sisters, and carriers communicated their results to significantly more sisters compared to uninformative (96% vs. 76%, FET = 0.02). The most important reason for communicating results was to provide genetic risk information; however, compared to uninformatives, carriers communicated their results to significantly more sisters to obtain emotional support (74%) and to get advice about medical decisions (42%) (FET = 0.001). Carriers also discussed the possibility of discrimination and recommendations for cancer management with significantly more sisters. Among sisters to whom BRCA1/2 test results were not communicated, the most important reason for not sharing test results was because of emotionally distant relationships. The results of this study suggest that probands are likely to quickly communicate their BRCA1/2 test results to relatives and that although needs for social support may motivate family communication, emotionally distant relationships may be a barrier to communication with relatives.

  13. Psychological health in siblings who lost a brother or sister to cancer 2 to 9 years earlier.

    Science.gov (United States)

    Eilegård, Alexandra; Steineck, Gunnar; Nyberg, Tommy; Kreicbergs, Ulrika

    2013-03-01

    The objective of this study was to assess long-term psychological distress in siblings who lost a brother or sister to cancer 2 to 9 years earlier, as compared with a control group of non-bereaved siblings from the general population. During 2009, we conducted a nationwide follow-up study in Sweden by using an anonymous study-specific questionnaire. Siblings who had lost a brother or sister to cancer between the years 2000 and 2007 and also a control group of non-bereaved siblings from the general population were invited to participate. The Hospital Anxiety and Depression Scale (HADS) was used to measure psychological distress, and to test for differences in the ordinal outcome responses between the groups, we used Wilcoxon-Mann-Whitney rank-sum test. Among the bereaved siblings, 174/240 (73%) participated and 219/293 (75%) among the non-bereaved. Self-assessed low self-esteem (p = 0.002), difficulties falling asleep (p = 0.005), and low level of personal maturity (p = 0.007) at follow-up were more prevalent among bereaved siblings. However, anxiety (p = 0.298) and depression (p = 0.946), according to HADS, were similar. Bereaved siblings are at increased risk of low self-esteem, low level of personal maturity and difficulties falling asleep as compared with non-bereaved peers. Yet, the bereaved were not more likely to report anxiety or depression. Copyright © 2012 John Wiley & Sons, Ltd.

  14. “Our vanishing glaciers”: One hundred years of glacier retreat in Three Sisters Area, Oregon Cascade Range

    Science.gov (United States)

    O'Connor, James E.

    2014-01-01

    In August 1910, thirty-nine members of the Mazamas Mountaineering Club ascended the peaks of the Three Sisters in central Oregon. While climbing, geologist Ira A. Williams photographed the surrounding scenery, including images of Collier Glacier. One hundred years later, U.S. Geological Survey research hydrologist Jim E. O’Connor matched those documented photographs with present day images — the result of which is a stunning lapse of glacial change in the Three Sister region. O’Connor asserts that “glaciers exist by the grace of climate,” and through a close examination of the history of the region’s glaciers, he provides an intriguing glimpse into the history of geological surveys and glacial studies in the Pacific Northwest, including their connection to significant scientific advances of the nineteenth century. The work of scientists and mountaineers who have monitored and recorded glacier changes for over a century allows us to see dramatic changes in a landscape that is especially sensitive to ongoing climate change.

  15. Introgression and selection shaped the evolutionary history of sympatric sister-species of coral reef fishes (genus: Haemulon)

    KAUST Repository

    Bernal, Moisés A.

    2016-11-22

    Closely related marine species with large overlapping ranges provide opportunities to study mechanisms of speciation, particularly when there is evidence of gene flow between such lineages. Here, we focus on a case of hybridization between the sympatric sister-species Haemulon maculicauda and H. flaviguttatum, using Sanger sequencing of mitochondrial and nuclear loci, as well as 2422 single nucleotide polymorphisms (SNPs) obtained via restriction site-associated DNA sequencing (RADSeq). Mitochondrial markers revealed a shared haplotype for COI and low divergence for CytB and CR between the sister-species. On the other hand, complete lineage sorting was observed at the nuclear loci and most of the SNPs. Under neutral expectations, the smaller effective population size of mtDNA should lead to fixation of mutations faster than nDNA. Thus, these results suggest that hybridization in the recent past (0.174-0.263Ma) led to introgression of the mtDNA, with little effect on the nuclear genome. Analyses of the SNP data revealed 28 loci potentially under divergent selection between the two species. The combination of mtDNA introgression and limited nuclear DNA introgression provides a mechanism for the evolution of independent lineages despite recurrent hybridization events. This study adds to the growing body of research that exemplifies how genetic divergence can be maintained in the presence of gene flow between closely related species.

  16. Novel insertion in exon 5 of the TCOF1 gene in twin sisters with Treacher Collins syndrome.

    Science.gov (United States)

    Marszałek-Kruk, Bożena Anna; Wójcicki, Piotr; Smigiel, Robert; Trzeciak, Wiesław H

    2012-08-01

    Treacher Collins syndrome (TCS) is associated with an abnormal differentiation of the first and second pharyngeal arches during fetal development. This causes mostly craniofacial deformities, which require numerous corrective surgeries. TCS is an autosomal dominant disorder and it occurs in the general population at a frequency of 1 in 50,000 live births. The syndrome is caused by mutations in the TCOF1 gene, which encodes the serine/alanine-rich protein named Treacle. Over 120 mutations of the TCOF1 gene responsible for TCS have been described. About 70% of recognized mutations are deletions, which lead to a frame shift, formation of a termination codon, and shortening of the protein product of the gene. Herewith, a new heterozygotic insertion, c.484_668ins185bp, was described in two monozygotic twin sisters suffering from TCS. This mutation was absent in their father, brother, and uncle, indicating a de novo origin. The insertion causes a shift in the reading frame and premature termination of translation at 167 aa. The novel insertion is the longest ever found in the TCOF1 gene and the only one found among monozygotic twin sisters.

  17. Reducing HIV risk among transgender women in Thailand: a quasi-experimental evaluation of the sisters program.

    Directory of Open Access Journals (Sweden)

    Duangta Pawa

    Full Text Available Transgender women are particularly at risk of HIV infection, but little evidence exists on effective HIV prevention strategies with this population. We evaluated whether Sisters, a peer-led program for transgender women, could reduce HIV risks in Pattaya, Thailand. The study used time-location sampling to recruit 308 transgender women in Pattaya into a behavioral survey in 2011. Coarsened exact matching was used to create statistically equivalent groups of program participants and non-participants, based on factors influencing likelihood of program participation. Using multivariable logistic regression, we estimated effects of any program participation and participation by delivery channel on: condom use at last sex; consistent condom and condom/water-based lubricant use in the past 3 months with commercial, casual, and regular partners; and receipt of HIV testing in the past 6 months. Program coverage reached 75% of the population. In a matched sub-sample (n = 238, participation in outreach was associated with consistent condom/water-based lubricant use with commercial partners (AOR 3.22, 95% CI 1.64-6.31. Attendance at the Sisters drop-in center was associated with receiving an HIV test (AOR 2.58, 95% CI 1.47-4.52. Dedicated transgender-friendly programs are effective at reducing HIV risks and require expansion to better serve this key population and improve HIV prevention strategies.

  18. Gymnosperm B-sister genes may be involved in ovule/seed development and, in some species, in the growth of fleshy fruit-like structures.

    Science.gov (United States)

    Lovisetto, Alessandro; Guzzo, Flavia; Busatto, Nicola; Casadoro, Giorgio

    2013-08-01

    The evolution of seeds together with the mechanisms related to their dispersal into the environment represented a turning point in the evolution of plants. Seeds are produced by gymnosperms and angiosperms but only the latter have an ovary to be transformed into a fruit. Yet some gymnosperms produce fleshy structures attractive to animals, thus behaving like fruits from a functional point of view. The aim of this work is to increase our knowledge of possible mechanisms common to the development of both gymnosperm and angiosperm fruits. B-sister genes from two gymnosperms (Ginkgo biloba and Taxus baccata) were isolated and studied. The Ginkgo gene was also functionally characterized by ectopically expressing it in tobacco. In Ginkgo the fleshy structure derives from the outer seed integument and the B-sister gene is involved in its growth. In Taxus the fleshy structure is formed de novo as an outgrowth of the ovule peduncle, and the B-sister gene is not involved in this growth. In transgenic tobacco the Ginkgo gene has a positive role in tissue growth and confirms its importance in ovule/seed development. This study suggests that B-sister genes have a main function in ovule/seed development and a subsidiary role in the formation of fleshy fruit-like structures when the latter have an ovular origin, as occurs in Ginkgo. Thus, the 'fruit function' of B-sister genes is quite old, already being present in Gymnosperms as ancient as Ginkgoales, and is also present in Angiosperms where a B-sister gene has been shown to be involved in the formation of the Arabidopsis fruit.

  19. Characterization of muntjac DNA

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R.C.

    1981-05-27

    Sister chromatid exchange (SCE) in muntjac chromosomes is generally proportional to the chromosomal DNA content, but the SCE frequency is reduced in the heterochromatic neck region of the X chromosome. The physical properties of muntjac DNA and the kinetics of repair of UV damage in muntjac heterochromatin and euchromatin were examined and compared with the distribution of sister chromatid exchange.

  20. Yeast Interacting Proteins Database: YDL089W, YDR233C [Yeast Interacting Proteins Database

    Lifescience Database Archive (English)

    Full Text Available rDNA repeat stability; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein...DNA repeat stability; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein l

  1. Yeast Interacting Proteins Database: YDL089W, YPR028W [Yeast Interacting Proteins Database

    Lifescience Database Archive (English)

    Full Text Available rDNA repeat stability; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein...ility; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein localizes to the

  2. Yeast Interacting Proteins Database: YDL089W, YCR086W [Yeast Interacting Proteins Database

    Lifescience Database Archive (English)

    Full Text Available rDNA repeat stability; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein...p, Lrs4p; required for rDNA repeat stability; null mutant causes increase in unequal sister-chromatid exchan

  3. The relationship of psychosocial factors to mammograms, physical activity, and fruit and vegetable consumption among sisters of breast cancer patients

    Directory of Open Access Journals (Sweden)

    Hartman SJ

    2011-08-01

    Full Text Available Sheri J Hartman1, Shira I Dunsiger1, Paul B Jacobsen21Centers for Behavioral and Preventive Medicine, The Miriam Hospital and W Alpert Medical School of Brown University, Providence, RI; 2Department of Health Outcomes and Behavior, H Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USAAbstract: This study examined the relationship of psychosocial factors to health-promoting behaviors in sisters of breast cancer patients. One hundred and twenty sisters of breast cancer patients completed questionnaires assessing response efficacy of mammography screenings, physical activity, and fruit and vegetable consumption on decreasing breast cancer risk, breast cancer worry, involvement in their sister’s cancer care, mammography screenings, physical activity, and fruit and vegetable consumption. Results indicate that greater perceived effectiveness for mammograms was associated with a 67% increase in odds of yearly mammograms. Greater involvement in the patient’s care was associated with a 7% decrease in odds of yearly mammograms. Greater perceived effectiveness for physical activity was significantly related to greater physical activity. There was a trend for greater perceived effectiveness for fruits and vegetables to be associated with consuming more fruits and vegetables. Breast cancer worry was not significantly associated with the outcomes. While perceived effectiveness for a specific health behavior in reducing breast cancer risk was consistently related to engaging in that health behavior, women reported significantly lower perceived effectiveness for physical activity and fruits and vegetables than for mammograms. Making women aware of the health benefits of these behaviors may be important in promoting changes.Keywords: breast cancer risk, mammograms, physical activity, diet, perceived effectiveness

  4. Comparative genomic analysis of the genus Staphylococcus including Staphylococcus aureus and its newly described sister species Staphylococcus simiae

    Science.gov (United States)

    2012-01-01

    Background Staphylococcus belongs to the Gram-positive low G + C content group of the Firmicutes division of bacteria. Staphylococcus aureus is an important human and veterinary pathogen that causes a broad spectrum of diseases, and has developed important multidrug resistant forms such as methicillin-resistant S. aureus (MRSA). Staphylococcus simiae was isolated from South American squirrel monkeys in 2000, and is a coagulase-negative bacterium, closely related, and possibly the sister group, to S. aureus. Comparative genomic analyses of closely related bacteria with different phenotypes can provide information relevant to understanding adaptation to host environment and mechanisms of pathogenicity. Results We determined a Roche/454 draft genome sequence for S. simiae and included it in comparative genomic analyses with 11 other Staphylococcus species including S. aureus. A genome based phylogeny of the genus confirms that S. simiae is the sister group to S. aureus and indicates that the most basal Staphylococcus lineage is Staphylococcus pseudintermedius, followed by Staphylococcus carnosus. Given the primary niche of these two latter taxa, compared to the other species in the genus, this phylogeny suggests that human adaptation evolved after the split of S. carnosus. The two coagulase-positive species (S. aureus and S. pseudintermedius) are not phylogenetically closest but share many virulence factors exclusively, suggesting that these genes were acquired by horizontal transfer. Enrichment in genes related to mobile elements such as prophage in S. aureus relative to S. simiae suggests that pathogenesis in the S. aureus group has developed by gene gain through horizontal transfer, after the split of S. aureus and S. simiae from their common ancestor. Conclusions Comparative genomic analyses across 12 Staphylococcus species provide hypotheses about lineages in which human adaptation has taken place and contributions of horizontal transfer in pathogenesis. PMID

  5. Global analysis of threat status reveals higher extinction risk in tropical than in temperate bird sister species

    Directory of Open Access Journals (Sweden)

    Reif Jiří

    2016-06-01

    Full Text Available Given increasing pressures upon biodiversity, identification of species’ traits related to elevated extinction risk is useful for more efficient allocation of limited resources for nature conservation. Despite its need, such a global analysis was lacking in the case of birds. Therefore, we performed this exercise for avian sister species using information about their global extinction risk from IUCN Red List. We focused on 113 pairs of sister species, each containing a threatened and an unthreatened species to factor out the effects of common evolutionary history on the revealed relationship. We collected data on five traits with expected relationships to species’ extinction risk based on previous studies performed at regional or national levels: breeding habitat (recognizing forest, grassland, wetland and oceanic species, latitudinal range position (temperate and tropics species, migration strategy (migratory and resident species, diet (carnivorous, insectivorous, herbivorous and omnivorous species and body mass. We related the extinction risk using IUCN threat level categories to species’ traits using generalised linear mixed effects models expecting lower risk for forest, temperate, omnivorous and smaller-bodied species. Our expectation was confirmed only in the case of latitudinal range position, as we revealed higher threat level for tropical than for temperate species. This relationship was robust to different methods of threat level expression and cannot be explained by a simple association of high bird species richness with the tropical zone. Instead, it seems that tropical species are more threatened because of their intrinsic characteristics such as slow life histories, adaptations to stable environments and small geographic ranges. These characteristics are obviously disadvantageous in conditions of current human-induced environmental perturbations. Moreover, given the absence of habitat effects, our study indicates that such

  6. Association of perceived racial discrimination with eating behaviors and obesity among participants of the SisterTalk study.

    Science.gov (United States)

    Johnson, Portia; Risica, Patricia Markham; Gans, Kim M; Kirtania, Usree; Kumanyika, Shiriki K

    2012-07-01

    The purpose of this study was to assess the association of perceived racial discrimination with emotional eating behaviors, weight status, and stress levels among obese African-American women, who volunteered to enter a weight control study (SisterTalk) in the New England region of the United States. The sample of women was taken from the baseline data of participants in SisterTalk, a randomized, controlled trial of a cable TV-delivered weight control program. Using the Krieger instrument, telephone and in-person surveys were used to assess perceived discrimination, emotional eating behaviors, and stress. Height and weight were measured to calculate BMI in order to assess weight status. ANOVA models were constructed to assess the association of discrimination with demographics. Correlations were calculated for discrimination, stress, emotional eating, and weight variables. ANOVA models were also constructed to assess discrimination with emotional eating, after adjusting for appropriate demographic variables. Perceived discrimination was associated with education and stress levels but was not associated with weight status (BMI). The frequency of eating when depressed or sad, and eating to manage stress, were both significantly higher among women who reported higher perceived discrimination and higher stress levels. Discrimination may contribute to stress that leads to eating for reasons other than hunger among African-American women, although the causal direction of associations cannot be determined with cross sectional data. Associations of discrimination with weight status were not found, although it is likely that emotional eating behaviors related to perceived discrimination are unhealthy. Future research should examine these relationships more closely in longitudinal studies.

  7. Comparative genomic analysis of the genus Staphylococcus including Staphylococcus aureus and its newly described sister species Staphylococcus simiae

    Directory of Open Access Journals (Sweden)

    Suzuki Haruo

    2012-01-01

    Full Text Available Abstract Background Staphylococcus belongs to the Gram-positive low G + C content group of the Firmicutes division of bacteria. Staphylococcus aureus is an important human and veterinary pathogen that causes a broad spectrum of diseases, and has developed important multidrug resistant forms such as methicillin-resistant S. aureus (MRSA. Staphylococcus simiae was isolated from South American squirrel monkeys in 2000, and is a coagulase-negative bacterium, closely related, and possibly the sister group, to S. aureus. Comparative genomic analyses of closely related bacteria with different phenotypes can provide information relevant to understanding adaptation to host environment and mechanisms of pathogenicity. Results We determined a Roche/454 draft genome sequence for S. simiae and included it in comparative genomic analyses with 11 other Staphylococcus species including S. aureus. A genome based phylogeny of the genus confirms that S. simiae is the sister group to S. aureus and indicates that the most basal Staphylococcus lineage is Staphylococcus pseudintermedius, followed by Staphylococcus carnosus. Given the primary niche of these two latter taxa, compared to the other species in the genus, this phylogeny suggests that human adaptation evolved after the split of S. carnosus. The two coagulase-positive species (S. aureus and S. pseudintermedius are not phylogenetically closest but share many virulence factors exclusively, suggesting that these genes were acquired by horizontal transfer. Enrichment in genes related to mobile elements such as prophage in S. aureus relative to S. simiae suggests that pathogenesis in the S. aureus group has developed by gene gain through horizontal transfer, after the split of S. aureus and S. simiae from their common ancestor. Conclusions Comparative genomic analyses across 12 Staphylococcus species provide hypotheses about lineages in which human adaptation has taken place and contributions of horizontal

  8. Monopolin subunit Csm1 associates with MIND complex to establish monopolar attachment of sister kinetochores at meiosis I.

    Science.gov (United States)

    Sarkar, Sourav; Shenoy, Rajesh T; Dalgaard, Jacob Z; Newnham, Louise; Hoffmann, Eva; Millar, Jonathan B A; Arumugam, Prakash

    2013-01-01

    Sexually reproducing organisms halve their cellular ploidy during gametogenesis by undergoing a specialized form of cell division known as meiosis. During meiosis, a single round of DNA replication is followed by two rounds of nuclear divisions (referred to as meiosis I and II). While sister kinetochores bind to microtubules emanating from opposite spindle poles during mitosis, they bind to microtubules originating from the same spindle pole during meiosis I. This phenomenon is referred to as mono-orientation and is essential for setting up the reductional mode of chromosome segregation during meiosis I. In budding yeast, mono-orientation depends on a four component protein complex referred to as monopolin which consists of two nucleolar proteins Csm1 and Lrs4, meiosis-specific protein Mam1 of unknown function and casein kinase Hrr25. Monopolin complex binds to kinetochores during meiosis I and prevents bipolar attachments. Although monopolin associates with kinetochores during meiosis I, its binding site(s) on the kinetochore is not known and its mechanism of action has not been established. By carrying out an imaging-based screen we have found that the MIND complex, a component of the central kinetochore, is required for monopolin association with kinetochores during meiosis. Furthermore, we demonstrate that interaction of monopolin subunit Csm1 with the N-terminal domain of MIND complex subunit Dsn1, is essential for both the association of monopolin with kinetochores and for monopolar attachment of sister kinetochores during meiosis I. As such this provides the first functional evidence for a monopolin-binding site at the kinetochore.

  9. Strain localization associated with channelized melt migration in upper mantle lithosphere: Insights from the Twin Sisters ultramafic complex, Washington, USA

    Science.gov (United States)

    Kruckenberg, Seth C.; Tikoff, Basil; Toy, Virginia G.; Newman, Julie; Young, Laura I.

    2013-05-01

    We present results of field, microstructural, and textural studies in the Twin Sisters ultramafic complex (Washington State) that document localized deformation associated with the formation of dunite channels in naturally deformed upper mantle. The Twin Sisters complex is a well-exposed, virtually unaltered section of upper mantle lithosphere comprised largely of dunite and harzburgite (in cm- to m-scale primary compositional layers), and variably deformed orthopyroxenite and clinopyroxenite dikes. A series of ˜N-S striking, m-scale dunite bands (typically with porphyroclastic texture) occur throughout the study area and crosscut both the primary compositional layers and older orthopyroxenite dikes. Structural relationships suggest that these dunite bands represent former zones of channelized melt migration (i.e., dunite channels), and that strain localization was associated with melt migration. Early formed orthopyroxenite dikes are either absent within cross-cutting dunite channels, or have been displaced within channels relative to their position in the adjacent host rocks. These pre-existing orthopyroxenite dikes provide strain markers illustrating that displacement was localized primarily along channel margins, which have opposite senses of shear. In all cases where offsets were noted, the center of the channel was moved southward relative to its margins. Material flow and strain was, therefore, partitioned within channels during melt migration, and dunite channels did not accommodate net shear displacement of the adjacent host peridotites. Primary compositional layers adjacent to dunite channels document opposite rotation of olivine [100] crystallographic axes on either side of channel margins, consistent with the kinematic reversal inferred from offset markers at the outcrop scale, suggesting that the formation of dunite channels also induced host rock deformation proximal to channels. Strain localization that was focused at the margin of the bands was

  10. Genome sequence and physiological analysis of Yamadazyma laniorum f.a. sp. nov. and a reevaluation of the apocryphal xylose fermentation of its sister species, Candida tenuis

    Science.gov (United States)

    Xylose fermentation is a rare trait that is immensely important to the cellulosic biofuel industry, and Candida tenuis is one of the few yeasts that has been reported with this trait. Here we report the isolation of two strains representing a candidate sister species to C. tenuis. Integrated analysi...

  11. Climate niches of milkweeds with plesiomorphic traits (Secamonoideae; Apocynaceae) and the milkweed sister group link ancient African climates and floral evolution.

    Science.gov (United States)

    Livshultz, Tatyana; Mead, Jerry V; Goyder, David J; Brannin, Michelle

    2011-12-01

    Climate change that increases mortality of plants and pollinators can create mate-finding Allee effects and thus act as a strong selective force on floral morphology. Milkweeds (Secamonoideae and Asclepiadoideae; Apocynaceae) are typically small plants of seasonally dry habitats, with pollinia and high pollen-transfer efficiency. Their sister group (tribe Baisseeae and Dewevrella) is mostly comprised of giant lianas of African rainforests, with pollen in monads. Comparison of the two groups motivated a new hypothesis: milkweeds evolved in the context of African aridification and the shifting of rainforest to dry forest. Pollinia and high pollen-transfer efficiency may have been adaptations that alleviated mate-finding Allee effects generated by high mortality during droughts. We formally tested whether milkweeds have a drier climate niche by comparing milkweeds with plesiomorphic traits (Secamonoideae) and the milkweed sister group in continental Africa. We georeferenced specimens of the milkweed sister group and Secamonoideae in continental Africa, extracted 19 climatic variables from the Worldclim model, conducted factor analysis to identify correlated suites of variables, and compared the frequency distributions of the two lineages relative to each factor. The distributions of Secamonoideae and the milkweed sister group differed significantly relative to four factors, each correlated with a distinct suite of climate parameters: (1) air temperature (Secamonoideae: cooler), (2) total and (3) summer precipitation (Secamonoideae: drier), and (4) temperature seasonality and isothermality (Secamonoideae: more seasonal and less isothermal). Secamonoideae in continental Africa inhabit drier, cooler sites than do the milkweed sister group, consistent with a shift from rainforests to dry forests in a cooling climate.

  12. Immune gene expression in Bombus terrestris: signatures of infection despite strong variation among populations, colonies, and sister workers.

    Directory of Open Access Journals (Sweden)

    Franziska S Brunner

    Full Text Available Ecological immunology relies on variation in resistance to parasites. Colonies of the bumblebee Bombus terrestris vary in their susceptibility to the trypanosome gut parasite Crithidia bombi, which reduces colony fitness. To understand the possible origin of this variation in resistance we assayed the expression of 28 immunologically important genes in foraging workers. We deliberately included natural variation of the host "environment" by using bees from colonies collected in two locations and sampling active foraging workers that were not age controlled. Immune gene expression patterns in response to C. bombi showed remarkable variability even among genetically similar sisters. Nevertheless, expression varied with parasite exposure, among colonies and, perhaps surprisingly, strongly among populations (collection sites. While only the antimicrobial peptide abaecin is universally up regulated upon exposure, linear discriminant analysis suggests that the overall exposure effect is driven by a combination of several immune pathways and further immune functions such as ROS regulation. Also, the differences among colonies in their immune gene expression profiles provide clues to the mechanistic basis of well-known inter-colony variation in susceptibility to this parasite. Our results show that transcriptional responses to parasite exposure can be detected in ecologically heterogeneous groups despite strong background noise.

  13. The mitochondrial genome of Paraspadella gotoi is highly reduced and reveals that chaetognaths are a sister-group to protostomes

    Energy Technology Data Exchange (ETDEWEB)

    Helfenbein, Kevin G.; Fourcade, H. Matthew; Vanjani, Rohit G.; Boore, Jeffrey L.

    2004-05-01

    We report the first complete mitochondrial (mt) DNA sequence from a member of the phylum Chaetognatha (arrow worms). The Paraspadella gotoi mtDNA is highly unusual, missing 23 of the genes commonly found in animal mtDNAs, including atp6, which has otherwise been found universally to be present. Its 14 genes are unusually arranged into two groups, one on each strand. One group is punctuated by numerous non-coding intergenic nucleotides, while the other group is tightly packed, having no non-coding nucleotides, leading to speculation that there are two transcription units with differing modes of expression. The phylogenetic position of the Chaetognatha within the Metazoa has long been uncertain, with conflicting or equivocal results from various morphological analyses and rRNA sequence comparisons. Comparisons here of amino acid sequences from mitochondrially encoded proteins gives a single most parsimonious tree that supports a position of Chaetognatha as sister to the protostomes studied here. From this, one can more clearly interpret the patterns of evolution of various developmental features, especially regarding the embryological fate of the blastopore.

  14. Multiple risk factors related to familial predisposition to anterior cruciate ligament injury: fraternal twin sisters with anterior cruciate ligament ruptures.

    Science.gov (United States)

    Hewett, T E; Lynch, T R; Myer, G D; Ford, K R; Gwin, R C; Heidt, R S

    2010-09-01

    A multifactorial combination of predictors may increase anterior cruciate ligament (ACL) injury risk in athletes. The objective of this twin study was to examine these risk factors to identify commonalities in risk factors that predisposed female fraternal twins to ACL injury. Female twins in high-risk sports were prospectively measured prior to an injury for neuromuscular control using three-dimensional motion analysis during landing, hamstrings and quadriceps muscular strength on a dynamometer and joint laxity using a modified Beighton-Horan index and a Compu-KT arthrometer. Intraoperative measures of femoral intercondylar notch width were recorded during ACL reconstruction. Abduction angles were increased at one knee in both of the twin sister athletes relative to uninjured controls at initial contact and at maximum displacement during landing. The twin female athletes that went on to ACL injury also demonstrated decreased peak knee flexion motion at both knees than uninjured females during landing. The twin athletes also had increased joint laxity and decreased hamstrings to quadriceps (H/Q) torque ratios compared to controls. Femoral intercondylar notch widths were also below the control mean in the twin siblings. Prescreened mature female twins that subsequently experienced ACL injury demonstrated multiple potential risk factors including: increased knee abduction angles, decreased knee flexion angles, increased general joint laxity, decreased H/Q ratios and femoral intercondylar notch width.

  15. Siblings' experiences of having a brother or sister with autism and mental retardation: a case study of 14 siblings from five families.

    Science.gov (United States)

    Benderix, Ylva; Sivberg, Bengt

    2007-10-01

    The aim of this study was to describe the present and past experiences of 14 siblings from five families in terms of having a brother or sister with autism and mental retardation. Personal interviews were conducted with the siblings before their brothers or sisters were moved to a newly opened group home. Qualitative content analysis was used for the analysis of the transcribed texts. The analysis resulted in seven content categories: precocious responsibility, feeling sorry, exposed to frightening behavior, empathetic feelings, hoping that a group home will be a relief, physical violence made siblings feel unsafe and anxious, and relations with friends were affected negatively. The conclusion is that these siblings' experiences revealed stressful life conditions. Counseling for the family and for siblings is recommended to help them deal with their feelings and problems. For the siblings in these five families, a group home was a relevant alternative as a temporary or permanent placement for the child with autism and mental retardation.

  16. Comparative phylogeography of two sister (congeneric) species of cardiid bivalve: Strong influence of habitat, life history and post-glacial history

    OpenAIRE

    Tarnowska, Katarzyna; Krakau, Manuela; Jacobsen, Sabine; Wo1owicz, Maciej; Féral, Jean-Pierre; Chenuil, Anne

    2012-01-01

    International audience; Sister (congeneric) species may exhibit disparate patterns of biogeographic genetic structures due to different life histories and habitat preferences. The common cockle Cerastoderma edule and the lagoon cockle Cerastoderma glaucum probably diverged from their common ancestor in the present territory of Sahara around 5 million years ago. Although it is difficult to separate both species morphologically, various genetic markers, both mitochondrial and nuclear, clearly d...

  17. [Sense of coherence and ways of coping in the relationship with brother or sister in healthy siblings of mentally ill persons].

    Science.gov (United States)

    Osuchowska-Kościjańska, Anna; Charzyńska, Katarzyna; Chadzyńska, Małgorzata; Drozdzyńska, Anna; Kasperek-Zimowska, Beata; Bednarek, Agata; Sawicka, Maryla

    2014-01-01

    The aim of the present study was to investigate sense of coherence in healthy siblings of persons suffering from schizophrenia as well as their ways of coping in the relationship with ill brother or sister. 40 healthy brothers and sisters of persons with ICD- 10 diagnosis of F20 to F29 participated in the present study. Orientation to Life Scale (SOC- 29) was used to assess sense of coherence and Ways of Coping with Stress questionnaire (SRSS) was used to examine stress coping strategies. Mean global score of siblings of persons with schizophrenia was 111 points. Subjects used coping strategies focused on problem significantly more often than those focused on emotions. Therapeutic work with healthy siblings should focus on strengthening sense of personal competence, development of personal resources and different ways of coping with stress, investigation of emotions that healthy siblings experience in the relationship with ill brother or sister as well as supporting the process of accepting changes in the relationship with the ill sibling.

  18. The Comparison About Tess andThird Sister You 's Tragic Destiny%比较苔丝与尤三姐的悲剧命运

    Institute of Scientific and Technical Information of China (English)

    冯涛

    2011-01-01

    Tess and Third Sister You are regarded to be the two fairly lifelike female characters in Chinese and foreign literature history;and their endings are terribly tragic.The family environment,the society of male rights and their own personalities constitute the primary elements of Tess and Third Sister You's tragic destiny.However,the reasons of their tragic destiny are different thoroughly,so are their attitudes towards tragedy.From the viewpoint,this paper attempts to make a comparison about Tess and Third Sister You 's Tragic Destiny.%在中外文学史上,苔丝和尤三姐是两个非常鲜活的女性形象,她们的结局都很悲惨,家庭环境,男权社会以及她们自身的性格特征都是造成她们悲剧命运的主要因素。然而,造成她们两人悲剧的成因和她们个人对待悲剧的态度是迥然不同的。从这点出发,对苔丝与尤三姐的悲剧命运进行了对比分析。

  19. Divergence of brain and retinal anatomy and histology in pelagic antarctic notothenioid fishes of the sister taxa Dissostichus and Pleuragramma.

    Science.gov (United States)

    Eastman, Joseph T; Lannoo, Michael J

    2011-04-01

    The neutrally buoyant Antarctic fishes of the sister taxa Dissostichus (D. eleginoides and D. mawsoni) and Pleuragramma antarcticum diverged early in the notothenioid radiation and filled different niches in the pelagic realm of the developing Southern Ocean. To assess the influence of phylogenetic and ecological factors in shaping neural morphology in these taxa, we studied the anatomy and histology of the brains and retinae, and determined the proportional weights of brain regions. With the brain of the non-Antarctic sister taxon Eleginops maclovinus as plesiomorphic, statistically significant departures in the brains of the two Antarctic taxa include reduction of the corpus cerebelli and expansion of the mesencephalon and medulla. Compared to Eleginops, both species also have a relatively smaller telencephalon, although this is significant only in Dissostichus. There are a number of apomorphic features in the brain of Pleuragramma including reduced olfactory nerves and bulbs, an extremely small corpus cerebelli and an expanded mesencephalon. Although there is not a significant difference in the relative weights of the medulla in the two taxa, the prominence of the eminentia granularis and bulging cap-like appearance of the crista cerebellaris are distinctive in Pleuragramma. Brain histology of Dissostichus and Pleuragramma reflects typical perciform patterns and the two species of Dissostichus are histologically identical. Lateral compression in Pleuragramma and notable lobation in Dissostichus also contribute to differences between the taxa. Compression in Pleuragramma is attributable to convergence on an anchovy/herring body shape and to the relatively large brain in this small fish. The less prominent pattern of lobation of the telencephalon, inferior lobes and corpus cerebelli in Pleuragramma probably reflects underlying histology, specifically a reduction in cellularity of the neuropil in the nuclei and lobes. The retinal histology of Dissostichus and

  20. Historical biogeography and diversification of truffles in the Tuberaceae and their newly identified southern hemisphere sister lineage.

    Directory of Open Access Journals (Sweden)

    Gregory Bonito

    Full Text Available Truffles have evolved from epigeous (aboveground ancestors in nearly every major lineage of fleshy fungi. Because accelerated rates of morphological evolution accompany the transition to the truffle form, closely related epigeous ancestors remain unknown for most truffle lineages. This is the case for the quintessential truffle genus Tuber, which includes species with socio-economic importance and esteemed culinary attributes. Ecologically, Tuber spp. form obligate mycorrhizal symbioses with diverse species of plant hosts including pines, oaks, poplars, orchids, and commercially important trees such as hazelnut and pecan. Unfortunately, limited geographic sampling and inconclusive phylogenetic relationships have obscured our understanding of their origin, biogeography, and diversification. To address this problem, we present a global sampling of Tuberaceae based on DNA sequence data from four loci for phylogenetic inference and molecular dating. Our well-resolved Tuberaceae phylogeny shows high levels of regional and continental endemism. We also identify a previously unknown epigeous member of the Tuberaceae--the South American cup-fungus Nothojafnea thaxteri (E.K. Cash Gamundí. Phylogenetic resolution was further improved through the inclusion of a previously unrecognized Southern hemisphere sister group of the Tuberaceae. This morphologically diverse assemblage of species includes truffle (e.g. Gymnohydnotrya spp. and non-truffle forms that are endemic to Australia and South America. Southern hemisphere taxa appear to have diverged more recently than the Northern hemisphere lineages. Our analysis of the Tuberaceae suggests that Tuber evolved from an epigeous ancestor. Molecular dating estimates Tuberaceae divergence in the late Jurassic (~156 million years ago, with subsequent radiations in the Cretaceous and Paleogene. Intra-continental diversification, limited long-distance dispersal, and ecological adaptations help to explain patterns of

  1. Does telomere length predict decline in physical functioning in older twin sisters during an 11-year follow-up?

    Science.gov (United States)

    Sillanpää, Elina; Törmäkangas, Timo; Rantanen, Taina; Kaprio, Jaakko; Sipilä, Sarianna

    2016-04-01

    Leukocyte telomere length (LTL) is known to be associated with mortality, but its association with age-related decline in physical functioning and the development of disability is less clear. This study examined the associations between LTL and physical functioning, and investigated whether LTL predicts level of physical functioning over an 11-year follow-up. Older mono- (MZ) and dizygotic (DZ) twin sisters (n = 386) participated in the study. Relative LTL was measured by qPCR at baseline. Physical functioning was measured by 6-min walking distance and level of physical activity (PA). Walking distance was measured at baseline and at 3-year follow-up. PA was assessed by questionnaire at baseline and at 3- and 11-year follow-ups. The baseline analysis was performed with path models, adjusted with age and within-pair dependence of twin pairs. The longitudinal analysis was performed with a repeated measures linear model adjusted for age and longitudinal within-pair dependence. A nonrandom missing data analysis was utilized. At baseline, in all individuals, LTL was associated with PA (est. 0.14, SE 0.06, p = 0.011), but not with walking distance. Over the follow-up, a borderline significant association was observed between LTL and walking distance (est. 0.14, SE 0.07, p = 0.060) and a significant association between LTL and PA (est. 0.19, SE 0.06, p = 0.001). The results suggest that LTL is associated with PA and may, therefore, serve as a biomarker predicting the development of disability. Longitudinal associations between LTL and PA were observed only when nonrandom data missingness was taken into account in the analysis.

  2. STRANGERS IN THE SAME COUNTRY: THE COMPLEXITY OF SISTERLY SOLIDARITY IN CATHERINE FILLOUX’S THE BEAUTY INSIDE

    Directory of Open Access Journals (Sweden)

    Eda DEDEBAŞ DÜNDAR

    2017-06-01

    Full Text Available Through the depiction of a sisterly solidarity and the priority of our responsibility for the other, French-American playwright Catherine Filloux’s play The Beauty Inside makes its audience bear witness not only to the tragedy of honor killings in Turkey but also to an amity that flourishes between a Westernized lawyer Devrim and a rape survivor Yalova introducing a form of familial bond that stems from our shared ethical space. With the help of its unique characters and stress on compassion, The Beauty Inside exemplifies an outstanding play that enhances the publicity of the theatre genre itself. This paper argues that through its rendering of two noteworthy characters from two conflicting sub-cultures of Turkey and their attempts to acknowledge their responsibility for the other, the play portrays a complex sisterhood that justifies the uplifting impact of face-to-face interaction and proposes a novel approach to humanitarianism in human rights theatre. Moreover, it accentuates travel, both as a physical expedition and a mental exploration, in its attempt to encounter the other and “the non-intentionality of consciousness” – to quote from Emmanuel Levinas. Divided in two major sections, this paper first discusses the theoretical perspectives surrounding travel theory and the concept of witnessing vulnerability and atrocities by referring to human rights theorists as well as Levinas’s concept of “face-to-face interaction” and then includes a close reading of The Beauty Inside as a distinguished play that aptly utilizes the theatre genre to serve a dual function: to publicize violations and to deliver an eye-opening alternative to our fear of the other by curtailing the proximity to the vulnerable.

  3. Contrasting genetic diversity patterns in two sister kelp species co-distributed along the coast of Brittany, France.

    Science.gov (United States)

    Robuchon, Marine; Le Gall, Line; Mauger, Stéphane; Valero, Myriam

    2014-06-01

    We investigated patterns of genetic structure in two sister kelp species to explore how distribution width along the shore, zonation, latitudinal distribution and historical factors contribute to contrasting patterns of genetic diversity. We implemented a hierarchical sampling scheme to compare patterns of genetic diversity and structure in these two kelp species co-distributed along the coasts of Brittany (France) using a total of 12 microsatellites, nine for Laminaria hyperborea and 11 for Laminaria digitata, of which eight amplified in both species. The genetic diversity and connectivity of L. hyperborea populations were greater than those of L. digitata populations in accordance with the larger cross-shore distribution width along the coast and the greater depth occupied by L. hyperborea populations in contrast to L. digitata populations. In addition, marginal populations showed reduced genetic diversity and connectivity, which erased isolation-by-distance patterns in both species. As L. digitata encounters its southern range limit in southern Brittany (SBr) while L. hyperborea extends down to mid-Portugal, it was possible to distinguish the effect of habitat continuity from range edge effects. We found that L. digitata did not harbour high regional diversity at its southern edge, as expected in a typical rear edge, suggesting that refuges from the last glacial maximum for L. digitata were probably not located in SBr, but most likely further north. For both species, the highest levels of genetic diversity were found in the Iroise Sea and Morlaix Bay, the two regions in which they are being currently harvested. Preserving genetic diversity of these two foundation species in these areas should, thus, be a priority for the management of this resource in Brittany.

  4. Flying lemurs – The 'flying tree shrews'? Molecular cytogenetic evidence for a Scandentia-Dermoptera sister clade

    Directory of Open Access Journals (Sweden)

    Volobouev Vitaly

    2008-05-01

    Full Text Available Abstract Background Flying lemurs or Colugos (order Dermoptera represent an ancient mammalian lineage that contains only two extant species. Although molecular evidence strongly supports that the orders Dermoptera, Scandentia, Lagomorpha, Rodentia and Primates form a superordinal clade called Supraprimates (or Euarchontoglires, the phylogenetic placement of Dermoptera within Supraprimates remains ambiguous. Results To search for cytogenetic signatures that could help to clarify the evolutionary affinities within this superordinal group, we have established a genome-wide comparative map between human and the Malayan flying lemur (Galeopterus variegatus by reciprocal chromosome painting using both human and G. variegatus chromosome-specific probes. The 22 human autosomal paints and the X chromosome paint defined 44 homologous segments in the G. variegatus genome. A putative inversion on GVA 11 was revealed by the hybridization patterns of human chromosome probes 16 and 19. Fifteen associations of human chromosome segments (HSA were detected in the G. variegatus genome: HSA1/3, 1/10, 2/21, 3/21, 4/8, 4/18, 7/15, 7/16, 7/19, 10/16, 12/22 (twice, 14/15, 16/19 (twice. Reverse painting of G. variegatus chromosome-specific paints onto human chromosomes confirmed the above results, and defined the origin of the homologous human chromosomal segments in these associations. In total, G. variegatus paints revealed 49 homologous chromosomal segments in the HSA genome. Conclusion Comparative analysis of our map with published maps from representative species of other placental orders, including Scandentia, Primates, Lagomorpha and Rodentia, suggests a signature rearrangement (HSA2q/21 association that links Scandentia and Dermoptera to one sister clade. Our results thus provide new evidence for the hypothesis that Scandentia and Dermoptera have a closer phylogenetic relationship to each other than either of them has to Primates.

  5. Sister Mary Joseph nodule

    OpenAIRE

    Kock, I.; Dekeyzer, S.; Smet, B S; Delrue, L

    2013-01-01

    A 64-year-old female presented with a three-month history of decreased appetite, nausea and progressive abdominal distension. Physical examination revealed a distended abdomen with a fluid wave and a hard periumbilical bluish swelling (Fig. A).

  6. Two Nepali Sisters

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    to Denmark and Seattle. They both use the connections and skills acquired in Japan, but one is now living in Seattle and the other in Kathmandu. One is a manager in a chocolate factory using Danish products in the Seattle area and the other has started an income generating environmental NGO in Nepal while...

  7. Two Nepali Sisters

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    at different times during the 1980s. The training was partly funded by official development assistance provided through the Japanese Ministry of International Trade and Industry (MITI). They used their training very differently, but between the two of them extended a family network from Japan and India...... to Denmark and Seattle. They both use the connections and skills acquired in Japan, but one is now living in Seattle and the other in Kathmandu. One is a manager in a chocolate factory using Danish products in the Seattle area and the other has started an income generating environmental NGO in Nepal while...

  8. Astronomy: Earth's seven sisters

    Science.gov (United States)

    Snellen, Ignas A. G.

    2017-02-01

    Seven small planets whose surfaces could harbour liquid water have been spotted around a nearby dwarf star. If such a configuration is common in planetary systems, our Galaxy could be teeming with Earth-like planets. See Letter p.456

  9. The Seven Sisters

    DEFF Research Database (Denmark)

    Söderqvist, Thomas

    2011-01-01

    Today, scientific biography is primarily thought of as a way of writing contextual history of science. But the genre has other functions as well. This article discusses seven kinds of ideal-typical subgenres of scientific biography. In addition to its mainstream function as an ancilla historiae......, respectively, commemoration. Finally, the use of scientific biography as a research (virtue) ethical genre, providing examples of 'the good life in science', is emphasized....

  10. SisterTalk: final results of a culturally tailored cable television delivered weight control program for Black women.

    Science.gov (United States)

    Risica, Patricia Markham; Gans, Kim M; Kumanyika, Shiriki; Kirtania, Usree; Lasater, Thomas M

    2013-12-27

    Obesity among Black women continues to exceed that of other women. Most weight loss programs created without reference to specific cultural contexts are less effective for Black than White women. Weight control approaches accessible to Black women and adapted to relevant cultural contexts are important for addressing this problem. This paper reports the final results of SisterTalk, the randomized controlled trial of a cable TV weight control program oriented toward Black women. A five group design included a comparison group and a 2 × 2 factorial comparison of a) interactive vs. passive programming and b) telephone social support vs no telephone support, with 12 weekly initial cable TV programs followed by 4 monthly booster videos. At baseline, 3, 8, and 12 months post randomization, telephone and in person surveys were administered on diet, physical activity, and physical measurements of height and weight were taken to calculate body mass index (BMI). Analysis of variance (ANOVA) was used to examine differences over time, and between treatment and comparison groups. Dose variables reflecting use of the TV/video and written materials were also assessed. At 3 months, BMI, weight, and dietary fat were significantly lower and physical activity significantly higher among women exposed to the Cable TV intervention compared to the wait-list comparison group. Significant dietary fat differences were still observed at 8 and 12 month evaluations, but not BMI or physical activity differences. Main effects were not observed for interactive programming or enhanced social support at any time point. Within the intervention group, higher watching of the TV series and higher reading of educational materials were both (separately) associated with significantly lower dietary fat. Cable TV was an effective delivery channel to assist Black women with weight control, increasing physical activity and decreasing dietary fat during an initial intervention period, but only dietary

  11. [What is the link between the sister of the "Titanic" and the history of medicine in Palestine?].

    Science.gov (United States)

    Greenberg, Zalman

    2006-06-01

    On 21st November 1916, the Royal Navy Hospital ship 'Britannic' (the sister ship of the 'Titanic') was torpedoed near the island of Kea in the Aegean Sea. Captain Dr. John Cropper, aged 52, was one of 30 people who drowned of the 1100 on board. Dr. Cropper was born in 1864, at Guisborough, England. He obtained his medical degree from Cambridge University in 1891. After his marriage to Anne Ellen Walker in 1895, the Church Missionary Society sent him on a medical mission to Palestine. Dr. Cropper stayed in Palestine for about 10 years working in Acre, Nablus, Ramallah and Jerusalem. He published his experiences in 35 articles and letters in English medical periodicals, more than anyone else did in Palestine at that time. In those publications, he described various operations that he carried out and observations on infectious diseases, most of which were the first descriptions from that remote and unhealthy country. His prominent research was in the field of malaria - the most common and important disease in Palestine during that period. It was less than two years after Grassi's discovery of the role of Anopheles mosquitoes as the vector of human malaria that Dr. Cropper carried out surveys of larval and adult mosquitoes in correlation with malarial distribution in Palestine. Dr. Cropper was the first who routinely examined slides microscopically in Palestine and correctly diagnosed the type of malaria. Dr. Cropper was also the first in Palestine to suggest antimalarial measures aimed directly at the mosquito vector and paid attention to ecological aspects such as breeding places and the daily behavior of adult mosquitoes. Dr. Cropper noted the common antimalarial measurements of that time, such as covering of wells, planting of Eucalyptus trees to drain swamps and the routine use of quinine as a preventive medicine, but he wrote that those measures were not effective under the local conditions. He suggested that the only effective measures must be aimed against the

  12. Ancestral polymorphism at the major histocompatibility complex (MHCIIß in the Nesospiza bunting species complex and its sister species (Rowettia goughensis

    Directory of Open Access Journals (Sweden)

    van Rensburg Alexandra

    2012-08-01

    Full Text Available Abstract Background The major histocompatibility complex (MHC is an important component of the vertebrate immune system and is frequently used to characterise adaptive variation in wild populations due to its co-evolution with pathogens. Passerine birds have an exceptionally diverse MHC with multiple gene copies and large numbers of alleles compared to other avian taxa. The Nesospiza bunting species complex (two species on Nightingale Island; one species with three sub-species on Inaccessible Island represents a rapid adaptive radiation at a small, isolated archipelago, and is thus an excellent model for the study of adaptation and speciation. In this first study of MHC in Nesospiza buntings, we aim to characterize MHCIIß variation, determine the strength of selection acting at this gene region and assess the level of shared polymorphism between the Nesospiza species complex and its putative sister taxon, Rowettia goughensis, from Gough Island. Results In total, 23 unique alleles were found in 14 Nesospiza and 2 R. goughensis individuals encoding at least four presumably functional loci and two pseudogenes. There was no evidence of ongoing selection on the peptide binding region (PBR. Of the 23 alleles, 15 were found on both the islands inhabited by Nesospiza species, and seven in both Nesospiza and Rowettia; indications of shared, ancestral polymorphism. A gene tree of Nesospiza MHCIIß alleles with several other passerine birds shows three highly supported Nesospiza-specific groups. All R. goughensis alleles were shared with Nesospiza, and these alleles were found in all three Nesospiza sequence groups in the gene tree, suggesting that most of the observed variation predates their phylogenetic split. Conclusions Lack of evidence of selection on the PBR, together with shared polymorphism across the gene tree, suggests that population variation of MHCIIß among Nesospiza and Rowettia is due to ancestral polymorphism rather than local selective

  13. The tapeworm Atractolytocestus tenuicollis (Cestoda: Caryophyllidea)--a sister species or ancestor of an invasive A. huronensis?

    Science.gov (United States)

    Králová-Hromadová, Ivica; Štefka, Jan; Bazsalovicsová, Eva; Bokorová, Silvia; Oros, Mikuláš

    2013-10-01

    phylogenetic analyses using cox1, ITS2 and combined cox1 + ITS2 sequences revealed close genetic interrelationship between A. tenuicollis and A. huronensis. Independently of a type of analysis and DNA region used, the topology of obtained trees was always identical; A. tenuicollis formed separate clade with A. huronensis forming a closely related sister group.

  14. Lens opacities in Bloom syndrome: case report and review of the literature.

    Science.gov (United States)

    Cefle, Kivanc; Ozturk, Sukru; Gozum, Nilufer; Duman, Nilgun; Mantar, Ferhan; Guler, Kerim; Palanduz, Sukru

    2007-09-01

    Bloom syndrome is an autosomal recessive disorder characterized by proportionate short stature, photosensitivity, immunodeficiency, hypogonadism and a tendency to develop various malignancies. The greatly increased frequency of sister chromatid exchanges (reciprocal exchange of homologous segments between the two sister chromatids of a chromosome) is regarded as pathognomonic for BS. We describe an 18-year old girl who presented with short stature. She was diagnosed with BS based on an extremely increased frequency of sister chromatid exchanges. Ophthalmological examination revealed mild lens opacities bilaterally, which, to our knowledge, has not been previously reported to be associated with BS.

  15. GORDITA (AGL63) is a young paralog of the Arabidopsis thaliana B(sister) MADS box gene ABS (TT16) that has undergone neofunctionalization.

    Science.gov (United States)

    Erdmann, Robert; Gramzow, Lydia; Melzer, Rainer; Theissen, Günter; Becker, Annette

    2010-09-01

    MIKC-type MADS domain proteins are key regulators of flower development in angiosperms. B(sister) genes constitute a clade with a close relationship to class B floral homeotic genes, and have been conserved for more than 300 million years. The loss-of-function phenotype of the A. thaliana B(sister) gene ABS is mild: mutants show reduced seed coloration and defects in endothelium development. This study focuses on GORDITA (GOA, formerly known as AGL63), the most closely related paralog of ABS in A. thaliana, which is thought to act redundantly with ABS. Phylogenetic trees reveal that the duplication leading to ABS and GOA occurred during diversification of the Brassicaceae, and further analyses show that GOA has evolved under relaxed selection pressure. The knockdown phenotype of GOA suggests a role for this gene in fruit longitudinal growth, while over-expression of GOA results in disorganized floral structure and addition of carpel-like features to sepals. Given the phylogeny and function of other B(sister) genes, our data suggest that GOA has evolved a new function as compared to ABS. Protein analysis reveals that the GOA-specific 'deviant' domain is required for protein dimerization, in contrast to other MIKC-type proteins that require the K domain for dimerization. Moreover, no shared protein interaction partners for ABS and GOA could be identified. Our experiments indicate that modification of a protein domain and a shift in expression pattern can lead to a novel gene function in a relatively short time, and highlight the molecular mechanism by which neofunctionalization following gene duplication can be achieved.

  16. Phylogenetic analysis of seven WRKY genes across the palm subtribe Attaleinae (Arecaceae) [corrected] identifies Syagrus as sister group of the coconut.

    Science.gov (United States)

    Meerow, Alan W; Noblick, Larry; Borrone, James W; Couvreur, Thomas L P; Mauro-Herrera, Margarita; Hahn, William J; Kuhn, David N; Nakamura, Kyoko; Oleas, Nora H; Schnell, Raymond J

    2009-10-06

    The Cocoseae is one of 13 tribes of Arecaceae subfam. Arecoideae, and contains a number of palms with significant economic importance, including the monotypic and pantropical Cocos nucifera L., the coconut, the origins of which have been one of the "abominable mysteries" of palm systematics for decades. Previous studies with predominantly plastid genes weakly supported American ancestry for the coconut but ambiguous sister relationships. In this paper, we use multiple single copy nuclear loci to address the phylogeny of the Cocoseae subtribe Attaleinae, and resolve the closest extant relative of the coconut. We present the results of combined analysis of DNA sequences of seven WRKY transcription factor loci across 72 samples of Arecaceae tribe Cocoseae subtribe Attaleinae, representing all genera classified within the subtribe, and three outgroup taxa with maximum parsimony, maximum likelihood, and Bayesian approaches, producing highly congruent and well-resolved trees that robustly identify the genus Syagrus as sister to Cocos and resolve novel and well-supported relationships among the other genera of the Attaleinae. We also address incongruence among the gene trees with gene tree reconciliation analysis, and assign estimated ages to the nodes of our tree. This study represents the as yet most extensive phylogenetic analyses of Cocoseae subtribe Attaleinae. We present a well-resolved and supported phylogeny of the subtribe that robustly indicates a sister relationship between Cocos and Syagrus. This is not only of biogeographic interest, but will also open fruitful avenues of inquiry regarding evolution of functional genes useful for crop improvement. Establishment of two major clades of American Attaleinae occurred in the Oligocene (ca. 37 MYBP) in Eastern Brazil. The divergence of Cocos from Syagrus is estimated at 35 MYBP. The biogeographic and morphological congruence that we see for clades resolved in the Attaleinae suggests that WRKY loci are informative

  17. Phylogenetic analysis of seven WRKY genes across the palm subtribe Attaleinae (Arecaceae [corrected] identifies Syagrus as sister group of the coconut.

    Directory of Open Access Journals (Sweden)

    Alan W Meerow

    Full Text Available BACKGROUND: The Cocoseae is one of 13 tribes of Arecaceae subfam. Arecoideae, and contains a number of palms with significant economic importance, including the monotypic and pantropical Cocos nucifera L., the coconut, the origins of which have been one of the "abominable mysteries" of palm systematics for decades. Previous studies with predominantly plastid genes weakly supported American ancestry for the coconut but ambiguous sister relationships. In this paper, we use multiple single copy nuclear loci to address the phylogeny of the Cocoseae subtribe Attaleinae, and resolve the closest extant relative of the coconut. METHODOLOGY/PRINCIPAL FINDINGS: We present the results of combined analysis of DNA sequences of seven WRKY transcription factor loci across 72 samples of Arecaceae tribe Cocoseae subtribe Attaleinae, representing all genera classified within the subtribe, and three outgroup taxa with maximum parsimony, maximum likelihood, and Bayesian approaches, producing highly congruent and well-resolved trees that robustly identify the genus Syagrus as sister to Cocos and resolve novel and well-supported relationships among the other genera of the Attaleinae. We also address incongruence among the gene trees with gene tree reconciliation analysis, and assign estimated ages to the nodes of our tree. CONCLUSIONS/SIGNIFICANCE: This study represents the as yet most extensive phylogenetic analyses of Cocoseae subtribe Attaleinae. We present a well-resolved and supported phylogeny of the subtribe that robustly indicates a sister relationship between Cocos and Syagrus. This is not only of biogeographic interest, but will also open fruitful avenues of inquiry regarding evolution of functional genes useful for crop improvement. Establishment of two major clades of American Attaleinae occurred in the Oligocene (ca. 37 MYBP in Eastern Brazil. The divergence of Cocos from Syagrus is estimated at 35 MYBP. The biogeographic and morphological congruence

  18. A pair of new sister species of Loneura (Psocodea, 'Psocoptera', Ptiloneuridae) from Valle del Cauca, Colombia, representing a new infrageneric group.

    Science.gov (United States)

    Aldrete, Alfonso N García; Nieto, Julián A Mendivil; Obando, Ranulfo González

    2012-01-01

    Two sister species of Loneura, from Valle del Cauca, Colombia, are here described and illustrated. They constitute a new species group that modifies the scheme of classification, proposed earlier for the genus by García Aldrete et al. (2011b). The new group is characterized by having the central sclerite of the male hypandrium with four posterior projections. A key to the males of Group II is included. The types are deposited in the Entomological Museum of the Universidad del Valle. Colombia may prove to be the most species rich area for Loneura.

  19. A pair of new sister species of Loneura (Psocodea, ‘Psocoptera’, Ptiloneuridae from Valle del Cauca, Colombia, representing a new infrageneric group

    Directory of Open Access Journals (Sweden)

    Alfonso Neri Garcia Aldrete

    2012-01-01

    Full Text Available Two sister species of Loneura, from Valle del Cauca, Colombia, are here described and illustrated. They constitute a new species group that modifies the scheme of classification, proposed earlier for the genus by García Aldrete et al. (2011b. The new group is characterized bythe central sclerite of the male hypandrium with four posterior projections. A key to the males of Group II is included. The types are deposited in the Entomological Museum of the Universidad del Valle. Colombia may prove to be the most species rich area for Loneura.

  20. A pair of new sister species of Loneura (Psocodea, ‘Psocoptera’, Ptiloneuridae) from Valle del Cauca, Colombia, representing a new infrageneric group

    Science.gov (United States)

    Aldrete, Alfonso N. García; Nieto, Julián A. Mendivil; Obando, Ranulfo González

    2012-01-01

    Abstract Two sister species of Loneura, from Valle del Cauca, Colombia, are here described and illustrated. They constitute a new species group that modifies the scheme of classification, proposed earlier for the genus by García Aldrete et al. (2011b). The new group is characterized by having the central sclerite of the male hypandrium with four posterior projections. A key to the males of Group II is included. The types are deposited in the Entomological Museum of the Universidad del Valle. Colombia may prove to be the most species rich area for Loneura. PMID:22423192

  1. Edith (1869-1938) and Florence (1870-1932) Stoney, two Irish sisters and their contribution to radiology during the World War I.

    Science.gov (United States)

    Guy, Jean M

    2013-05-01

    Edith and Florence Stoney, two sisters born in Dublin and working in London, responded to the summons of suffragists and offered themselves for medical service in World War I. Each had a strong scientific background and experience that they were able to use in setting up and running radiological services in Belgium, France, Serbia and Macedonia. The British War Office was reluctant to employ women doctors but the work Florence and her colleagues achieved persuaded Sir Alfred Keogh that Florence should be the first woman doctor to be employed in a military hospital in England.

  2. 卵子发育障碍原发性不孕姐妹2例%Primary Infertility for Oocyte Developmental Disorders of Two Sister-cases

    Institute of Scientific and Technical Information of China (English)

    薛石龙; 张学红

    2013-01-01

    Objective: To report two sister-cases of primary infertility for oocyte developmental disorders. Methods: A retrospective clinical study was performed to analyze two sister-cases of oocyte developmental disorders. Results: Two sister-cases underwent outpatient ovulation induction by conventional GnRHa protocol. There were only cumulus granulosa cell clusters without oocytes through microscopic examination on retrieval day. Oocytes were also not obtained by remedial hCG treatment. Thus oocyte dys-plasia could be diagnosed. Subsequently it was acquired that their grandparents were cousin consanguineous marriages. Younger sister-patient with donor oocyte cycle surgery got successful pregnancy of intrauterine single fetal. Conclusion: The family and medical history should be asked in detail for IVF treatment. Donor scheme for oocyte developmental disorders is a feasible and effective option.%目的:报道2例IVF治疗中卵子发育障碍原发性不孕姐妹患者.方法:对本院收治的2例卵子发育障碍原发性不孕患者姐妹进行回顾性总结与分析.结果:均采用常规GnRHa长方案促排卵,取卵日卵泡穿刺镜检仅见卵丘颗粒细胞团,均未见到卵子,补救性hCG治疗亦未取得卵子,诊断为卵子发育异常.追问病史得知其祖父母为表兄妹近亲婚配.患者(妹妹)行受卵治疗,宫内单胎成功妊娠.结论:门诊IVF治疗建病历时应详细询问患者家族史,供卵方案是目前IVF治疗卵子发育障碍原发性不孕较常用且有效的方法.

  3. MicroRNAs and phylogenomics resolve the relationships of Tardigrada and suggest that velvet worms are the sister group of Arthropoda.

    Science.gov (United States)

    Campbell, Lahcen I; Rota-Stabelli, Omar; Edgecombe, Gregory D; Marchioro, Trevor; Longhorn, Stuart J; Telford, Maximilian J; Philippe, Hervé; Rebecchi, Lorena; Peterson, Kevin J; Pisani, Davide

    2011-09-20

    Morphological data traditionally group Tardigrada (water bears), Onychophora (velvet worms), and Arthropoda (e.g., spiders, insects, and their allies) into a monophyletic group of invertebrates with walking appendages known as the Panarthropoda. However, molecular data generally do not support the inclusion of tardigrades within the Panarthropoda, but instead place them closer to Nematoda (roundworms). Here we present results from the analyses of two independent genomic datasets, expressed sequence tags (ESTs) and microRNAs (miRNAs), which congruently resolve the phylogenetic relationships of Tardigrada. Our EST analyses, based on 49,023 amino acid sites from 255 proteins, significantly support a monophyletic Panarthropoda including Tardigrada and suggest a sister group relationship between Arthropoda and Onychophora. Using careful experimental manipulations--comparisons of model fit, signal dissection, and taxonomic pruning--we show that support for a Tardigrada + Nematoda group derives from the phylogenetic artifact of long-branch attraction. Our small RNA libraries fully support our EST results; no miRNAs were found to link Tardigrada and Nematoda, whereas all panarthropods were found to share one unique miRNA (miR-276). In addition, Onychophora and Arthropoda were found to share a second miRNA (miR-305). Our study confirms the monophyly of the legged ecdysozoans, shows that past support for a Tardigrada + Nematoda group was due to long-branch attraction, and suggests that the velvet worms are the sister group to the arthropods.

  4. Nuclear and Related Analytical Techniques Used to Study the Anthropogenic Impact on the Sister River in the Vicinity of the Town of Klin (Moscow Region, Russia)

    CERN Document Server

    Morzhukhina, S V; Chermnykh, L P; Khodakovsky, L P; Frontasyeva, M V; Gundorina, S F

    2001-01-01

    The ecological fate of small rivers, tributaries of the Volga River, is of great concern in the national program of the Russian Federation "Restoration of the Volga River". The results on the elaborated hydrochemical and saprobiological water examination of the Sister River are reported along with the results on the multielement chemical analysis of surface sediments in the catchment of the town of Klin (Moscow Region) known for its numerous industrial and chemical enterprises with heavy contaminant inputs. Epithermal neutron activation analysis was used to study heavy metals and other toxic elements in bottom sediments. A total of 42 elements including Pb, Cu, Cd and Hg were determined by polarography (method of inverse voltamperometry). Metal/Al rations which express the relative mobility of the elements follow the sequence: Fe > Mg > K > Na > Ca >> Zr > Mn > Zn = Sr > Cr > V > Ni = As > Co. Elevated concentrations of Cd, Pb, Zn and Cu in the bottom sediments of the Sister River reinforced us to determine t...

  5. Thermal evolution of the Sisters shear zone, southern New Zealand; Formation of the Great South Basin and onset of Pacific-Antarctic spreading

    Science.gov (United States)

    Kula, Joseph; Tulloch, Andy J.; Spell, Terry L.; Wells, Michael L.; Zanetti, Kathleen A.

    2009-10-01

    The separation of Zealandia from West Antarctica was the final stage in the Cretaceous breakup of the Gondwana Pacific margin. Continental extension resulting in formation of the Great South Basin and thinning of the Campbell Plateau leading to development of the Pacific-Antarctic spreading ridge was partially accommodated along the Sisters shear zone. This east-northeast striking brittle-ductile structure exposed along the southeast coast of Stewart Island, New Zealand, is a greenschist facies extensional shear zone that separates a hanging wall of chloritic, brecciated granites, and undeformed conglomerate from a footwall of mylonitic Carboniferous and Early Cretaceous granites. This complex structure exhibits bivergent kinematics and can be subdivided into a northern and southern segment. The 40Ar/39Ar thermochronology indicates that cooling of the shear zone footwall began at ˜94 Ma with accelerated cooling over the interval ˜89-82 Ma. Structural and thermochronological data indicate a spatial and temporal link between the Sisters shear zone, initial sedimentation within the offshore Great South Basin, extension of the Campbell Plateau, and initiation of the Pacific-Antarctic spreading ridge.

  6. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the continued development of a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and...

  7. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and inversions) have profound genetic...

  8. Test for Chemical Induction of Chromosome Aberrations in Cultured Chinese Hamster Ovary (CHO) Cells With and Without Metabolic Activation. Test Article: Dimethylamine-2-2ethyl azide (DMAZ)

    Science.gov (United States)

    2008-07-26

    chromosomes leading to four-armed configurations. This could be asymmetrical with formation of a dicentric and an acentric chromatid, ifunion is complete...chromatid union. Dicentric - an asymmetrical exchange between two chromosomes resulting in a chromosome with two centromeres with or without an...no sister chromatid union. ’ d - Dicentric - an asymmetrical exchange between two chromosomes resulting, r dm in a chromosome with two centromeres

  9. Evaluation of Dimethyl Methylphosphonate and Exo-Tetrahydrodi- (Cyclopentadiene) in a Battery of in Vitro Short-Term Assays

    Science.gov (United States)

    1983-02-01

    sites of both chromatids of a chromosome . These include breaks, fragments, markers (i.e., dicentrics , rings), and gaps. 2. Chromatid aberrations - changes...Ames Salmonella/mammalian microsomal mutagenicity assay, the CHO/HGPRT gene mutation assay, the CHO/sister chromatid exchange assay, the CHO/ chromosome ...exhibited a low clastogenic activity in the CHO/ chromosome aberrations assay and was negative in the remaining four assays. Compound JP-1O also had a

  10. Chlorambucil induced chromosome damage in juvenile chronic arthritis.

    Science.gov (United States)

    Palmer, R G; Varonos, S; Doré, C J; Denman, A M; Ansell, B M

    1985-01-01

    Sister chromatid exchanges, a sensitive measure of chromosome damage, were counted in peripheral blood lymphocytes from 23 patients with juvenile chronic arthritis receiving long term, low dose chlorambucil treatment. Thirty five patients with juvenile chronic arthritis who had not been treated with cytotoxic drugs served as controls. All of the treated patients have cells with abnormal sister chromatid exchange frequencies. Damage is related to the daily dose and may, in part, be determined by the duration of treatment. Sister chromatid exchanges from nine patients who had received chlorambucil at some time in the past remained high for at least five months after stopping the drug. Long term follow up will determine whether sister chromatid exchange analysis can help predict those most at risk of drug induced malignancies. Images Fig. 1 PMID:4073932

  11. Single-cell template strand sequencing by Strand-seq enables the characterization of individual homologs

    NARCIS (Netherlands)

    Sanders, Ashley D; Falconer, Ester; Hills, Mark; Spierings, Diana C J; Lansdorp, Peter M.

    The ability to distinguish between genome sequences of homologous chromosomes in single cells is important for studies of copy-neutral genomic rearrangements (such as inversions and translocations), building chromosome-length haplotypes, refining genome assemblies, mapping sister chromatid exchange

  12. Experiment list: SRX140359 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available tioning. Involved in sister chromatid cohesion. Associat...ylation. Can dimerize, mediating long-range chromatin looping. When bound to chromatin, provides an anchor point for nucleosomes posi

  13. Reference: 368 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available h its predicted role in the release of sister chromatid cohesion, immunolocalization studies showed that the removal...ent and provide direct evidence that AESP is required for the removal of cohesin from meiotic chromosomes. A

  14. Protein (Viridiplantae): 405344 [PGDBj - Ortholog DB

    Lifescience Database Archive (English)

    Full Text Available 3 ... 424551:133 ... 424574:133 ... 4107:133 49274:207 4081:207 ... PREDICTED: sister chromatid cohesion protein PDS5-like Solanum lycopersicum MEALVADGLLRHCDMDLKVSVASCISEIMRITAPDQPYKDSILKC

  15. Comparison of the structure and musculature of male terminalia in the tribe Cidariini Duponchel (Lepidoptera: Geometridae: Larentiinae) once again throws into doubt a sister relationship with the Xanthorhoini.

    Science.gov (United States)

    Schmidt, Olga

    2014-08-25

    The structure and musculature of the male terminalia are described and illustrated in 11 genera of the tribe Cidariini (Lepidoptera, Geometridae, Larentiinae) from the Holarctic and Oriental regions. Nine genital muscles were identified: m1, m2(10), m3(2), m4, m5(7), m6(5), m7(6), m8(3) and m21. Variation in the insertion of the muscles m1, m3(2), m4, m5(7), m6(5) and m8(3) on the sclerites in several generic groups of the tribe Cidariini is discussed, revealing that the Thera species group does not share some apparently cidariine characters. A comparative analysis of the musculature in the tribes Cidariini and Xanthorhoini questions the sister relationship of these tribes that was suggested by earlier studies. The application of the terms 'anellus lobes' and 'labides' is discussed. 

  16. “It was that chalice he broke…”: James Joyce’s Dissatisfaction with Religion in His Short Story, The Sisters

    Directory of Open Access Journals (Sweden)

    Ali Gunes

    2013-06-01

    Full Text Available This paper examines James Joyce’s dissatisfaction and frustration with the established religion and the Catholic Church in this earliest short story The Sisters. In so doing, the paper focuses upon two strategies or two conditions used by Joyce in the story to represent his relentlessness with the church and the priesthood. One of them is his use of “pederasty” between the priest and young children, by which Joyce disgraces the image of the priesthood and the church. The second one is the “broken” image of the “chalice” as an important symbol. By means of these two strategies, Joyce not only deconstructs the trustworthy image of the church and the priesthood but also becomes able to create a free space outside the influence of the border of the church for his artistic vocation.

  17. 美国当代儿童文学童稚情愫探究--以Ten Ways to Make My Sister Disappear为例

    Institute of Scientific and Technical Information of China (English)

    韦小岿

    2016-01-01

    美国女作家诺迈·福克斯·梅泽(Norma Fox Mazer)所著Ten Ways to Make My Sister Disappear,以生动细腻的笔触,描绘出十岁女孩Sprig对于十二岁姐姐Dakota爱恨交加的内心世界。全书以儿童本位为创作宗旨,充满狂放的想象,以多元化故事结构铺陈,渲染滑稽夸张的故事效果,生动再现美国儿童典型心理及价值取向。本文从童言、童心、童趣三个层面探讨其文学创作特色。

  18. A sister of PIN1 gene in tomato (Solanum lycopersicum) defines leaf and flower organ initiation patterns by maintaining epidermal auxin flux.

    Science.gov (United States)

    Martinez, Ciera C; Koenig, Daniel; Chitwood, Daniel H; Sinha, Neelima R

    2016-11-01

    The spatiotemporal localization of the plant hormone auxin acts as a positional cue during early leaf and flower organogenesis. One of the main contributors to auxin localization is the auxin efflux carrier PIN-FORMED1 (PIN1). Phylogenetic analysis has revealed that PIN1 genes are split into two sister clades; PIN1 and the relatively uncharacterized Sister-Of-PIN1 (SoPIN1). In this paper we identify entire-2 as a loss-of-function SlSoPIN1a (Solyc10g078370) mutant in Solanum lycopersicum. The entire-2 plants are unable to specify proper leaf initiation leading to a frequent switch from the wild type spiral phyllotactic pattern to distichous and decussate patterns. Leaves in entire-2 are large and less complex and the leaflets display spatial deformities in lamina expansion, vascular development, and margin specification. During sympodial growth in entire-2 the specification of organ position and identity is greatly affected resulting in variable branching patterns on the main sympodial and inflorescence axes. To understand how SlSoPIN1a functions in establishing proper auxin maxima we used the auxin signaling reporter DR5: Venus to visualize differences in auxin localization between entire-2 and wild type. DR5: Venus visualization shows a widening of auxin localization which spreads to subepidermal tissue layers during early leaf and flower organogenesis, showing that SoPIN1 functions to focus auxin signaling to the epidermal layer. The striking spatial deformities observed in entire-2 help provide a mechanistic framework for explaining the function of the SoPIN1 clade in S.lycopersicum. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  19. The Relationship Between Brothers and Sisters in The Book of Songs%论《诗经》中的兄弟姐妹关系

    Institute of Scientific and Technical Information of China (English)

    吕静

    2012-01-01

    The relationship between brothers and sisters is an important aspect of Chinese family ethics.There are 25 poems about the relationship in The Book of Songs.Most of them praise the harmonious relationship between brothers,but a few of poems about love and family depict the image of brothers who take a indifferent attitude towards their sisters.Patriarchal clan system and sexist propriety system caused the different relationship.%兄弟姐妹关系是中国家庭伦理关系中的一个重要方面。《诗经》中有25篇涉及这一关系的诗篇,其中大部分为兄友弟恭的和睦关系,只有"国风"中少数婚恋诗描写薄情寡义的兄弟形象。两类截然不同的同辈血亲关系之形成皆与当时宗法制度和礼教制度相关:一方面,周代早期家族笼罩下的家庭模式和宗法政治体制需要和睦的兄弟关系来巩固贵族统治;另一方面,周代后期男性在家庭中的权威地位逐步巩固,男尊女卑的礼教制度使兄妹关系走向冷漠无情。

  20. Serotonin transporter binding of [123I]ADAM in bulimic women, their healthy twin sisters, and healthy women: a SPET study

    Directory of Open Access Journals (Sweden)

    Kaprio Jaakko

    2007-05-01

    Full Text Available Abstract Background Bulimia Nervosa (BN is believed to be caused by an interaction of genetic and environmental factors. Previous studies support the existence of a bulimia-related endophenotype as well as disturbances in serotonin (5-HT transmission. We studied serotonin transporter (SERT binding in BN, and to investigate the possibility of a SERT-related endophenotype for BN, did this in a sample of female twins. We hypothesized clearly reduced SERT binding in BN women as opposed to healthy women, and intermediate SERT binding in unaffected co-twins. Methods We studied 13 female twins with BN (9 with purging and 4 with non-purging BN and 25 healthy women, including 6 healthy twin sisters of BN patients and 19 women from 10 healthy twin pairs. [123I]ADAM, a selective SERT radioligand for single photon emission tomography (SPET imaging, was used to assess SERT availability in the midbrain and the thalamus. Results No differences in SERT binding were evident when comparing the BN women, their unaffected co-twins and the healthy controls (p = 0.14. The healthy sisters of the BN patients and the healthy control women had similar SERT binding in both brain regions. In a post hoc subgroup analysis, the purging bulimics had higher SERT binding than the healthy women in the midbrain (p = 0.03, but not in the thalamus. Conclusion Our finding of increased SERT binding in the midbrain in the purging BN women raises the possibility that this subgroup of bulimics might differ in serotonergic function from the non-purging ones. The similarity of the unaffected co-twins and the healthy controls doesn't support our initial assumption of a SERT-related endophenotype for BN. Due to the small sample size, our results need to be interpreted with caution and verified in a larger sample.

  1. Ter um irmão especial: convivendo com a Síndrome de Down Having a special brother/sister: living together with the Down Syndrome

    Directory of Open Access Journals (Sweden)

    Eucia Beatriz Lopes Petean

    2005-12-01

    Full Text Available O presente estudo teve por objetivos conhecer como é a relação entre irmãos mais velhos de pessoas com diagnóstico de Síndrome de Down (SD; que informações e sentimentos possuem sobre o diagnóstico; se houve ou não modificações na dinâmica familiar e em suas próprias vidas. Foram entrevistadas 11 pessoas, de ambos os sexos, com idade superior a dez anos, sendo, cada uma, o irmão mais velho de criança com diagnóstico de SD, sendo realizada análise quantitativa de dados da amostra e análise quantitativa-interpretativa e qualitativa para os dados da entrevista. Os dados mostram que a maioria dos sujeitos (90,9% sabe o nome da Síndrome e foram informados pela mãe logo após o nascimento do irmão, seis deles consideram que reagiram normalmente à notícia. Quanto às responsabilidades adquiridas, a maioria, 90,9%, são responsáveis pelas atividades de vida diária; 27,27% deles consideram que houve acréscimo de responsabilidade em suas vidas em decorrência do nascimento do irmão com SD. Em relação ao sentimento que apresentam por terem um irmão especial, 54,54% consideram como positivo, ou seja, disseram que também sentem-se especiais. Na falta (morte dos pais, a metade dos participantes informa que eles serão os responsáveis legais deste irmão. Pode-se concluir que o nascimento de um irmão com SD tem conseqüências na rotina de vida dos irmãos mais velhos, trazendo modificações e responsabilidades para eles. Entretanto, parece ter um efeito menos dirigido para a desestrutura psicológica, sendo poucas as manifestações de sentimentos extremos, ficando apenas no nível da tristeza, quando são expressos.The present study intended to know about the relation among older brothers/sisters of people with a diagnosis of Down Syndrome (DS, regarding to information and feelings they have about this diagnosis, and if changes have occurred within family dynamics and their own lives. Eleven people were interviewed, from

  2. DNA asymmetry in stem cells - immortal or mortal?

    Science.gov (United States)

    Yadlapalli, Swathi; Yamashita, Yukiko M

    2013-09-15

    The immortal strand hypothesis proposes that stem cells retain a template copy of genomic DNA (i.e. an 'immortal strand') to avoid replication-induced mutations. An alternative hypothesis suggests that certain cells segregate sister chromatids non-randomly to transmit distinct epigenetic information. However, this area of research has been highly controversial, with conflicting data even from the same cell types. Moreover, historically, the same term of 'non-random sister chromatid segregation' or 'biased sister chromatid segregation' has been used to indicate distinct biological processes, generating a confusion in the biological significance and potential mechanism of each phenomenon. Here, we discuss the models of non-random sister chromatid segregation, and we explore the strengths and limitations of the various techniques and experimental model systems used to study this question. We also describe our recent study on Drosophila male germline stem cells, where sister chromatids of X and Y chromosomes are segregated non-randomly during cell division. We aim to integrate the existing evidence to speculate on the underlying mechanisms and biological relevance of this long-standing observation on non-random sister chromatid segregation.

  3. Phylogeography of Indo-Pacific reef fishes: sister wrassesCoris gaimardandC. cuvieriin the Red Sea, Indian Ocean and Pacific Ocean

    KAUST Repository

    Ahti, Pauliina A.

    2016-02-01

    Aim: The aim of this study was to resolve the evolutionary history, biogeographical barriers and population histories for sister species of wrasses, the African Coris (Coris cuvieri) in the Indian Ocean and Red Sea, and the Yellowtail Coris (Coris gaimard) in the Pacific Ocean. Glacial sea level fluctuations during the Pleistocene have shaped the evolutionary trajectories of Indo-Pacific marine fauna, primarily by creating barriers between the Red Sea, Indian Ocean and Pacific Ocean. Here, we evaluate the influence of these episodic glacial barriers on sister species C. cuvieri and C. gaimard. Location: Red Sea, Indian Ocean, Pacific Ocean. Methods: Sequences from mitochondrial DNA cytochrome oxidase c subunit I (COI), and nuclear introns gonadotropin-releasing hormone (GnRH) and ribosomal S7 protein were analysed in 426 individuals from across the range of both species. Median-joining networks, analysis of molecular variance and Bayesian estimates of the time since most recent common ancestor were used to resolve recent population history and connectivity. Results: Cytochrome oxidase c subunit I haplotypes showed a divergence of 0.97% between species, and nuclear alleles were shared between species. No population structure was detected between the Indian Ocean and Red Sea. The strongest signal of population structure was in C. gaimard between the Hawaiian biogeographical province and other Pacific locations (COI ϕ(symbol)ST = 0.040-0.173, P < 0.006; S7 ϕ(symbol)ST = 0.046, P < 0.001; GnRH ϕ(symbol)ST = 0.022, P < 0.005). Time to most recent common ancestor is c. 2.12 Ma for C. cuvieri and 1.76 Ma for C. gaimard. Main conclusions: We demonstrate an Indian-Pacific divergence of c. 2 Myr and high contemporary gene flow between the Red Sea and Indian Ocean, mediated in part by the long pelagic larval stage. The discovery of hybrids at Christmas Island indicates that Indian and Pacific lineages have come into secondary contact after allopatric isolation. Subspecies

  4. Cross species amplification ability of novel microsatellites isolated from Jatropha curcas and genetic relationship with sister taxa : Cross species amplification and genetic relationship of Jatropha using novel microsatellites

    KAUST Repository

    Pamidimarri, D. V N N Sudheer

    2010-07-30

    The present investigation was undertaken with an aim to check the ability of cross species amplification of microsatellite markers isolated from Jatropha curcas-a renewable source of biodiesel to deduce the generic relationship with its six sister taxa (J. glandulifera, J. gossypifolia, J. integerrima, J. multifida, J. podagrica, and J. tanjorensis). Out of the 49 markers checked 31 markers showed cross species amplification in all the species studied. JCDS-30, JCDS-69, JCDS-26, JCMS-13 and JCMS-21 amplified in J. curcas. However, these markers did not show any cross species amplification. Overall percentage of polymorphism (PP) among the species studied was 38% and the mean genetic similarity (GS) was found to be 0.86. The highest PP (24) and least GS (0.76) was found between J. curcas/J. podagrica and J. curcas/J. multifida and least PP (4.44) and highest GS (0.96) was found between J. integerrima/J. tanjorensis. Dendrogram analysis showed good congruence to RAPD and AFLP than nrDNA ITS data reported earlier. The characterized microsatellites will pave way for intraspecies molecular characterization which can be further utilized in species differentiation, molecular identification, characterization of interspecific hybrids, exploitation of genetic resource management and genetic improvement of the species through marker assisted breeding for economically important traits. © 2010 Springer Science+Business Media B.V.

  5. centrosomin's beautiful sister (cbs) encodes a GRIP-domain protein that marks Golgi inheritance and functions in the centrosome cycle in Drosophila.

    Science.gov (United States)

    Eisman, Robert C; Stewart, Natasha; Miller, David; Kaufman, Thomas C

    2006-08-15

    The mechanism of inheritance of the Golgi complex is an important problem in cell biology. In this study, we examine the localization and function of a Golgi protein encoded by centrosomin's beautiful sister (cbs) during cleavage in Drosophila melanogaster. Cbs contains a GRIP domain that is 57% identical to vertebrate Golgin-97. Cbs undergoes a dramatic relocalization during mitosis from the cytoplasm to an association with chromosomes from late prometaphase to early telophase, by a transport mechanism that requires the GRIP domain and Arl1, the product of the Arf72A locus. Additionally, Cbs remains independent of the endoplasmic reticulum throughout cleavage. The use of RNAi, Arf72A mutant analysis and ectopic expression of the GRIP domain, shows that cycling of Cbs during mitosis is required for the centrosome cycle. The effects on the centrosome cycle depend on Cbs concentration and Cbs transport from the cytoplasm to DNA. When Cbs levels are reduced centrosomes fail to mature, and when Cbs transport is impeded by ectopic expression of the GRIP domain, centrosomes undergo hypertrophy. We propose that, Cbs is a trans-Golgi protein that links Golgi inheritance to the cell cycle and the Drosophila Golgi is more vertebrate-like than previously recognized.

  6. Contrasting patterns of gene flow between sister plant species in the understorey of African moist forests - the case of sympatric and parapatric Marantaceae species.

    Science.gov (United States)

    Ley, A C; Hardy, O J

    2014-08-01

    Gene flow within and between species is a fundamental process shaping the evolutionary history of taxa. However, the extent of hybridization and reinforcement is little documented in the tropics. Here we explore the pattern of gene flow between three sister species from the herbaceous genus Marantochloa (Marantaceae), sympatrically distributed in the understorey of the African rainforest, using data from the chloroplast and nuclear genomes (DNA sequences and AFLP). We found highly contrasting patterns: while there was no evidence of gene flow between M. congensis and M. monophylla, species identity between M. monophylla and M. incertifolia was maintained despite considerable gene flow. We hypothesize that M. incertifolia originated from an ancient hybridization event between M. congensis and M. monophylla, considering the current absence of hybridization between the two assumed parent species, the rare presence of shared haplotypes between all three species and the high percentage of haplotypes shared by M. incertifolia with each of the two parent species. This example is contrasted with two parapatrically distributed species from the same family in the genus Haumania forming a hybrid zone restricted to the area of overlap. This work illustrates the diversity of speciation/introgression patterns that can potentially occur in the flora of tropical Africa.

  7. Two-stage rifting of Zealandia-Australia-Antarctica: Evidence from 40Ar/39Ar thermochronometry of the Sisters shear zone, Stewart Island, New Zealand

    Science.gov (United States)

    Kula, Joseph; Tulloch, Andy; Spell, Terry L.; Wells, Michael L.

    2007-05-01

    The Sisters shear zone is a newly discovered Late Cretaceous detachment fault system exposed for 40 km along the southeast coast of Stewart Island, southernmost New Zealand. Footwall rocks consist of variably deformed ca. 310 and 105 Ma granites that range from undeformed to protomylonite, mylonite, and ultramylonite. The hanging wall includes non-marine conglomerate and brittley deformed granite. K-feldspar thermochronometry of the footwall indicates moderately rapid cooling (20 30 C°/m.y.) due to tectonic denudation over the interval ca. 89 82 Ma. Return to slow cooling at 82 Ma coincides with the age of the oldest seafloor adjacent to the Campbell Plateau and reflects the mechanical transition from continental extension to lithospheric rupture and formation of the Pacific-Antarctic Ridge. Our findings support a two-stage rift model for continental breakup of this part of the Gondwana margin. Stage one (ca. 101 88 Ma) is the northward propagation of continental extension and the Tasman Ridge as recorded in mylonite dredged from the Ross Sea and the Paparoa core complex. Stage two (ca. 89 82 Ma) is extension between the Campbell Plateau and West Antarctica leading to formation of the Pacific-Antarctic Ridge.

  8. The Role of Sister Cities’ Staff Exchanges in Developing “Learning Cities”: Exploring Necessary and Sufficient Conditions in Social Capital Development Utilizing Proportional Odds Modeling

    Directory of Open Access Journals (Sweden)

    Patrick Henry Buckley

    2015-06-01

    Full Text Available In the last half century former international adversaries have become cooperators through networking and knowledge sharing for decision making aimed at improving quality of life and sustainability; nowhere has this been more striking then at the urban level where such activity is seen as a key component in building “learning cities” through the development of social capital. Although mega-cities have been leaders in such efforts, mid-sized cities with lesser resource endowments have striven to follow by focusing on more frugal sister city type exchanges. The underlying thesis of our research is that great value can be derived from city-to-city exchanges through social capital development. However, such a study must differentiate between necessary and sufficient conditions. Past studies assumed necessary conditions were met and immediately jumped to demonstrating the existence of structural relationships by measuring networking while further assuming that the existence of such demonstrated a parallel development of cognitive social capital. Our research addresses this lacuna by stepping back and critically examining these assumptions. To accomplish this goal we use a Proportional Odds Modeling with a Cumulative Logit Link approach to demonstrate the existence of a common latent structure, hence asserting that necessary conditions are met.

  9. The Influence of Anton Chekhov on Samuel Beckett: Inaction and Investment of hope into Godot-like Figures in Three Sisters and Waiting for Godot

    Directory of Open Access Journals (Sweden)

    Samira Sasani

    2011-01-01

    Full Text Available Anton Chekhov has been very much influential on modern drama, especially on the Theatre of the Absurd; however, not much work has been done on his influence on the absurdist playwrights. Considering Harold Bloom’s definition of ‘influence’—writing “much like” someone in the past—the seminal influence of Chekhov on Beckett is studied in this article. Chekhov in his plays, especially his major plays, very much like Beckett’s waiting for Godot, portrays people who are passively waiting and investing their entire hope into Godot-like figures without taking any action. Thus, the sense of ennui, desperation and consequently disappointment of these characters originates from their unreasonable inaction, stagnancy and their passivity while waiting, rather than ‘waiting for Godot figures’. This article tries to show the influence of Chekhov on Samuel Beckett, investigating the similarities in form, atmosphere and theme between Waiting for Godot, the paradigm of the Theatre of the Absurd, and Three Sisters, one of Chekhov’s major plays

  10. A Sister Group Contrast Using Untargeted Global Metabolomic Analysis Delineates the Biochemical Regulation Underlying Desiccation Tolerance in Sporobolus stapfianus[C][W][OA

    Science.gov (United States)

    Oliver, Melvin J.; Guo, Lining; Alexander, Danny C.; Ryals, John A.; Wone, Bernard W.M.; Cushman, John C.

    2011-01-01

    Understanding how plants tolerate dehydration is a prerequisite for developing novel strategies for improving drought tolerance. The desiccation-tolerant (DT) Sporobolus stapfianus and the desiccation-sensitive (DS) Sporobolus pyramidalis formed a sister group contrast to reveal adaptive metabolic responses to dehydration using untargeted global metabolomic analysis. Young leaves from both grasses at full hydration or at 60% relative water content (RWC) and from S. stapfianus at lower RWCs were analyzed using liquid and gas chromatography linked to mass spectrometry or tandem mass spectrometry. Comparison of the two species in the fully hydrated state revealed intrinsic differences between the two metabolomes. S. stapfianus had higher concentrations of osmolytes, lower concentrations of metabolites associated with energy metabolism, and higher concentrations of nitrogen metabolites, suggesting that it is primed metabolically for dehydration stress. Further reduction of the leaf RWC to 60% instigated a metabolic shift in S. stapfianus toward the production of protective compounds, whereas S. pyramidalis responded differently. The metabolomes of S. stapfianus leaves below 40% RWC were strongly directed toward antioxidant production, nitrogen remobilization, ammonia detoxification, and soluble sugar production. Collectively, the metabolic profiles obtained uncovered a cascade of biochemical regulation strategies critical to the survival of S. stapfianus under desiccation. PMID:21467579

  11. The desert tortoise trichotomy: Mexico hosts a third, new sister-species of tortoise in the Gopherus morafkai–G. agassizii group

    Science.gov (United States)

    Edwards, Taylor; Karl, Alice E.; Vaughn, Mercy; Rosen, Philip C.; Torres, Cristina Meléndez; Murphy, Robert W.

    2016-01-01

    Abstract Desert tortoises (Testudines; Testudinidae; Gopherus agassizii group) have an extensive distribution throughout the Mojave, Colorado, and Sonoran desert regions. Not surprisingly, they exhibit a tremendous amount of ecological, behavioral, morphological and genetic variation. Gopherus agassizii was considered a single species for almost 150 years but recently the species was split into the nominate form and Morafka’s desert tortoise, Gopherus morafkai, the latter occurring south and east of the Colorado River. Whereas a large body of literature focuses on tortoises in the United States, a dearth of investigations exists for Mexican animals. Notwithstanding, Mexican populations of desert tortoises in the southern part of the range of Gopherus morafkai are distinct, particularly where the tortoises occur in tropical thornscrub and tropical deciduous forest. Recent studies have shed light on the ecology, morphology and genetics of these southern ‘desert’ tortoises. All evidence warrants recognition of this clade as a distinctive taxon and herein we describe it as Gopherus evgoodei sp. n. The description of the new species significantly reduces and limits the distribution of Gopherus morafkai to desertscrub habitat only. By contrast, Gopherus evgoodei sp. n. occurs in thornscrub and tropical deciduous forests only and this leaves it with the smallest range of the three sister species. We present conservation implications for the newly described Gopherus evgoodei, which already faces impending threats. PMID:27006625

  12. Detection of Wolbachia pipientis, including a new strain containing the wsp gene, in two sister species of Paraphlebotomus sandflies, potential vectors of zoonotic cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Parviz Parvizi

    2013-06-01

    Full Text Available Individual, naturally occurring Phlebotomus mongolensis and Phlebotomus caucasicus from Iran were screened for infections with the maternally inherited intracellular Rickettsia-like bacterium Wolbachia pipientis via targeting a major surface protein gene (wsp. The main objective of this study was to determine if W. pipientis could be detected in these species. The sandflies were screened using polymerase chain reaction to amplify a fragment of the Wolbachia surface protein gene. The obtained sequences were edited and aligned with database sequences to identify W. pipientis haplotypes. Two strains of Wolbachia were found. Strain Turk 54 (accession EU780683 is widespread and has previously been reported in Phlebotomus papatasi and other insects. Strain Turk 07 (accession KC576916 is a novel strain, found for first time in the two sister species. A-group strains of W. pipientis occur throughout much of the habitat of these sandflies. It is possible that Wolbachia is transferred via horizontal transmission. Horizontal transfer could shed light on sandfly control because Wolbachia is believed to drive a deleterious gene into sandflies that reduces their natural population density. With regard to our findings in this study, we can conclude that one species of sandfly can be infected with different Wolbachia strains and that different species of sandflies can be infected with a common strain.

  13. Chiasmatic and achiasmatic inverted meiosis of plants with holocentric chromosomes

    Science.gov (United States)

    Cabral, Gabriela; Marques, André; Schubert, Veit; Pedrosa-Harand, Andrea; Schlögelhofer, Peter

    2014-01-01

    Meiosis is a specialized cell division in sexually reproducing organisms before gamete formation. Following DNA replication, the canonical sequence in species with monocentric chromosomes is characterized by reductional segregation of homologous chromosomes during the first and equational segregation of sister chromatids during the second meiotic division. Species with holocentric chromosomes employ specific adaptations to ensure regular disjunction during meiosis. Here we present the analysis of two closely related plant species with holocentric chromosomes that display an inversion of the canonical meiotic sequence, with the equational division preceding the reductional. In-depth analysis of the meiotic divisions of Rhynchospora pubera and R. tenuis reveals that during meiosis I sister chromatids are bi-oriented, display amphitelic attachment to the spindle and are subsequently separated. During prophase II, chromatids are connected by thin chromatin threads that appear instrumental for the regular disjunction of homologous non-sister chromatids in meiosis II. PMID:25295686

  14. 1例双胞胎Crouzon综合征姐妹的临床及影像学特征报道%A case report on the clinical and imaging characteristics of crouzon syndrome of twin sisters

    Institute of Scientific and Technical Information of China (English)

    刘光健; 叶天雄; 朱飞奇; 陈学强; 王晓勋

    2010-01-01

    This paper reports the clinical and imaging characteristics of twin sisters with Crouzon syndrome. When the twin sisters were 1.5 years old, they acquired the symptoms of apophysised skull and protrusion eyeballs, as well as intermittent snoring, open-mouth breathing, apnea and constipation. Their parents'marriage was not consanguineous. Based on the computerized tomographic scanning, the axis oculi of the twin sisters are protracted, eye balls are significantly protruding and rima oculi is widening. Magnetic resonance imaging scanning showed that the skull's anteroposterior diameters are shortened, the upper-infra diameters are extended, so the skulls are turriform.%本文报道了一例双胞胎Crouzon综合征姐妹的临床及影像学特征.两患儿出生1年半后,逐渐出现头颅变尖和眼球突出,另有间断打鼾、张口呼吸、呼吸暂停和便秘.父母非近亲结婚.体检发现两患儿头颅上突,呈塔形;眼裂增宽,眼球突出.眼眶CT扫描结果显示两患儿双侧眼轴前突,眼球半脱位;颅脑MRI扫描结果显示两患儿颅骨前后径短,上下径长,头颅呈塔形.

  15. 姐妹同患硬斑病合并桥本甲状腺炎二例%Morphea complicated by Hashimoto's thyroiditis in two sisters

    Institute of Scientific and Technical Information of China (English)

    刘金鹏; 于晓虹; 杨国玲; 宋智琦

    2015-01-01

    Morphea complicated by Hashimoto's thyroiditis is reported in two sisters.Case 1:a 64-year-old female presented with skin rashes on the anterior neck,trunk and bilateral anterior shins for 5 years,itching skin rashes on the perineum for 4 years,and Hashimoto's thyroiditis for 9 years.Physical examination revealed grade 1 enlargement of firm thyroid gland without exophthalmos or pretibial myxedema.Dermatological examination showed pink patches on the neck and breast,sclerosis and atrophy of skin over the back,porcelain-white patches on the perineum.Histopathological findings suggested the diagnosis of morphea on the breast and lichen sclerosus et atrophicus on the perineum.Case 2:a 55-year-old female,who was the younger sister of case 1,suffered from gradual sclerosis and atrophy of skin in the left inframammary region and abdominal region for 4 years,as well as Hashimoto's thyroiditis for 3 years.Similarly,physical examination revealed grade 1 enlargement of firm thyroid gland without exophthalmos or pretibial myxedema.Hypopigmentation,sclerosis and atrophy of skin were observed in the left inframammary region,abdominal region and central back region.Histopathological examination suggested a diagnosis of morphea.According to the clinical and histopathological manifestations,periodic acid-Schiff staining and thyroid gland function test results,the 2 cases were both diagnosed as morphea complicated by Hashimoto's thyroiditis.%报告姐妹俩同患硬斑病合并桥本甲状腺炎.例1女,64岁,颈前、躯干和双胫前皮疹5年,会阴部皮疹伴瘙痒4年,既往桥本甲状腺炎病史9年.体检:甲状腺Ⅰ度肿大,质韧,无突眼、胫前黏液水肿等表现.颈部、前胸淡红色斑片,后背部硬化萎缩,会阴部瓷白色斑块.皮损组织病理提示:(前胸)硬斑病,(外阴)硬化萎缩性苔藓.例2女,例1的妹妹,55岁,左乳下及腹部皮肤逐渐硬化萎缩4年,既往桥本甲状腺炎病史3年.体检:甲状腺Ⅰ度肿大,质韧,无突

  16. 同一家庭3个姐妹色觉障碍%Color vision deficiency of three sisters in the same family

    Institute of Scientific and Technical Information of China (English)

    Nimet; Unay; Gündogan; Feride; Iffet; Sahin; Sansal; Gedik; Ozge; Pekdogan; Yonca; Akova

    2007-01-01

    目的:评价我校医学生和她的家庭成员先天色觉障碍的遗传特征,以建立其遗传模式.方法:运用Ishihara(石原)假同色图试验测定色觉障碍,用FW100色调试验评估其类型.并进行眼科检查和遗传学研究,建立色盲家谱,并对她的家庭给予遗传学咨询.结果:眼科检测结果显示双眼最佳矫正视力为20/20(1.0),近视矫正屈光度-2D,裂隙灯检测和眼压测量结果在正常范围,眼底镜检查视神经、黄斑和周边视网膜均正常,其它外眼评估和神经学检测正常,先证者的姐妹和她父母的眼科检测也正常,3姐妹和父亲的IPPT试验错误得分为19~20/25,结果和红绿色盲中绿色觉异常者一致.染色体分析和卵巢周期均正常.结论:根据她家谱,她的色盲是伴X染色体的隐性外显率模式的遗传特征.%· AIM: To evaluate genetic characteristics of congenital color vision deficiency of our medical student and her family subjects for establishing the mode of inheritance.· METHODS: Ishihara Pseudo-isochromatic Plate Test (IPPT)was used for determining the color vision deficiency and Farnsworth 100 Hue test (F100HT) was done for evaluating the type of color vision deficiency. Family pedigree was established for the color blindness, ophthalmologic examinations and genetic studies were done. Genetic counseling was given to her family.· RESULTS: Ocular examination revealed best correction bilateral visual acuity of 20/20 in both eyes, with myopic correction (-2.0D). Slit-lamp examination and intraocular pressure measurement were within normal limits and funduscopy revealed normal optic nerve, macula and retinal periphery. All other external ocular assessment and neurological examinations were normal. Proband's sisters and her parents' ophthalmic examinations were also normal. The error scores of three sisters and their father were found 19-20/25 in IPPT. The results were consistent as deutran of red-green color blindness. The

  17. Cucumber (Cucumis sativus) and melon (C. melo) have numerous wild relatives in Asia and Australia, and the sister species of melon is from Australia.

    Science.gov (United States)

    Sebastian, Patrizia; Schaefer, Hanno; Telford, Ian R H; Renner, Susanne S

    2010-08-10

    Among the fundamental questions regarding cultivated plants is their geographic origin and region of domestication. The genus Cucumis, which includes cucumber (Cucumis sativus) and melon (Cucumis melo), has numerous wild African species, and it has therefore been assumed that melon originated in Africa. For cucumber, this seemed less likely because wild cucumbers exist in India and a closely related species lives in the Eastern Himalayas. Using DNA sequences from plastid and nuclear markers for some 100 Cucumis accessions from Africa, Australia, and Asia, we show here that melon and cucumber are of Asian origin and have numerous previously overlooked species-level relatives in Australia and around the Indian Ocean. The wild progenitor of C. melo occurs in India, and our data confirm that the Southeast Asian Cucumis hystrix is the closest relative of cucumber. Most surprisingly, the closest relative of melon is Cucumis picrocarpus from Australia. C. melo diverged from this Australian sister species approximately 3 Ma, and both diverged from the remaining Asian/Australian species approximately 10 Ma. The Asian/Australian Cucumis clade comprises at least 25 species, nine of them new to science, and diverged from its African relatives in the Miocene, approximately 12 Ma. Range reconstruction under maximum likelihood suggests Asia as the ancestral area for the most recent common ancestor of melon and cucumber, fitting with both having progenitor populations in the Himalayan region and high genetic diversity of C. melo landraces in India and China. Future investigations of wild species related to melon and cucumber should concentrate on Asia and Australia.

  18. Long-term panmixia in a cosmopolitan Indo-Pacific coral reef fish and a nebulous genetic boundary with its broadly sympatric sister species

    KAUST Repository

    Horne, J. B.

    2013-01-11

    Phylogeographical studies have shown that some shallow-water marine organisms, such as certain coral reef fishes, lack spatial population structure at oceanic scales, despite vast distances of pelagic habitat between reefs and other dispersal barriers. However, whether these dispersive widespread taxa constitute long-term panmictic populations across their species ranges remains unknown. Conventional phylogeographical inferences frequently fail to distinguish between long-term panmixia and metapopulations connected by gene flow. Moreover, marine organisms have notoriously large effective population sizes that confound population structure detection. Therefore, at what spatial scale marine populations experience independent evolutionary trajectories and ultimately species divergence is still unclear. Here, we present a phylogeographical study of a cosmopolitan Indo-Pacific coral reef fish Naso hexacanthus and its sister species Naso caesius, using two mtDNA and two nDNA markers. The purpose of this study was two-fold: first, to test for broad-scale panmixia in N. hexacanthus by fitting the data to various phylogeographical models within a Bayesian statistical framework, and second, to explore patterns of genetic divergence between the two broadly sympatric species. We report that N. hexacanthus shows little population structure across the Indo-Pacific and a range-wide, long-term panmictic population model best fit the data. Hence, this species presently comprises a single evolutionary unit across much of the tropical Indian and Pacific Oceans. Naso hexacanthus and N. caesius were not reciprocally monophyletic in the mtDNA markers but showed varying degrees of population level divergence in the two nuclear introns. Overall, patterns are consistent with secondary introgression following a period of isolation, which may be attributed to oceanographic conditions of the mid to late Pleistocene, when these two species appear to have diverged. © 2013 The Authors. Journal

  19. For mothers and sisters: care of the reproductive female body in the medico-ritual world of early and medieval Japan.

    Science.gov (United States)

    Triplett, Katja

    2014-01-01

    While married female members of the Japanese aristocracy followed the ideal of bearing children, female Buddhist novices and ordained women, often belonging to the aristocracy themselves, had to abstain from sexual activity and reproduction in accordance with the ordination rules. Infertility was considered with disdain by the first group, whereas not bearing children was the utmost expression of leading a virtuous life for the second group. However, both groups were concerned with keeping their physical bodies healthy: some to become mothers, the others to live as nuns or religious sisters. Focusing on the early medieval period, this paper examines various sources to illuminate the ways in which women were cared for and the kind of views and ideas that informed this care. Instead of looking at the ancient methods of treatment through a modern "scientific" lens and sorting them into "proto-scientific" and "superstitious" categories, medico-ritual and religious views on the female body are explored as facets of the worldview prevalent in the period under consideration. Special attention is paid to relevant chapters of the first medical work produced in Japan, the Ishinpō, compiled by a court physician, Tanba no Yasuyori, in the late 10th century CE. The investigation of other sources, such as Buddhist legends and doctrinal texts, suggests that women were recommended to seek to overcome their femaleness altogether by transforming their female bodies into male bodies in order to reach ultimate "healing" in terms of salvation. In lay circles, however, the Buddhist divinities and other powerful deities were worshipped to ensure this-worldly "healing" in terms of successful procreation and continuation of the family line.

  20. Comparative phylogeography of two sister (congeneric) species of cardiid bivalve: Strong influence of habitat, life history and post-glacial history

    Science.gov (United States)

    Tarnowska, Katarzyna; Krakau, Manuela; Jacobsen, Sabine; Wołowicz, Maciej; Féral, Jean-Pierre; Chenuil, Anne

    2012-07-01

    Sister (congeneric) species may exhibit disparate patterns of biogeographic genetic structures due to different life histories and habitat preferences. The common cockle Cerastoderma edule and the lagoon cockle Cerastoderma glaucum probably diverged from their common ancestor in the present territory of Sahara around 5 million years ago. Although it is difficult to separate both species morphologically, various genetic markers, both mitochondrial and nuclear, clearly distinguish them. Furthermore, their lifestyles are different, as C. edule has a much less fragmented coastal habitat and a longer duration of pelagic larval stage than C. glaucum. A comparative genetic analysis was conducted on 17 populations of C. edule and 13 populations of C. glaucum using a 506 bp fragment of mitochondrial DNA (COI). We tested the hypothesis that differences in habitat types and life history are reflected in the genetic structure patterns of these two cockles. Indeed substantial differences in population genetic structures between them are revealed. Genetic diversity within C. glaucum populations decreases northwards as a consequence of post-glacial (re)colonization from southern refugia, while C. edule displays an opposite pattern indicating survival in glacial refuges in the northern Atlantic. Among populations within geographic groups, genetic differentiation is low in C. edule, probably as a result of larval dispersal with coastal currents, while it is extremely high in C. glaucum, best explained by the fragmented habitats. Interestingly, long distance divergence is less expressed in C. glaucum than in C. edule, which supports the speculation that migrating birds (frequently observed in lagoons) may occasionally transport the former more often or more efficiently than the latter. The approach applied in this study (e.g., rarefaction procedure, selection of samples of both species from the same regions) enabled a new and reliable comparative analysis of the existing raw