1,304 research outputs found
Single cell epigenomic and transcriptomic analysis uncovers potential transcription factors regulating mitotic/meiotic switch
In order to reveal the complex mechanism governing the mitotic/meiotic switch in female germ cells at epigenomic and genomic levels, we examined the chromatin accessibility (scATAC-seq) and the transcriptional dynamics (scRNA-seq) in germ cells of mouse embryonic ovary between E11.5 to 13.5 at single-cell resolution. Adopting a strict transcription factors (TFs) screening framework that makes it easier to understand the single-cell chromatin signature and a TF interaction algorithm that integrates the transcript levels, chromatin accessibility, and motif scores, we identified 14 TFs potentially regulating the mitotic/meiotic switch, including TCFL5, E2F1, E2F2, E2F6, E2F8, BATF3, SP1, FOS, FOXN3, VEZF1, GBX2, CEBPG, JUND, and TFDP1. Focusing on TCFL5, we constructed Tcfl5(+/-) mice which showed significantly reduced fertility and found that decreasing TCFL5 expression in cultured E12.5 ovaries by RNAi impaired meiotic progression from leptotene to zygotene. Bioinformatics analysis of published results of the embryonic germ cell transcriptome and the finding that in these cells central meiotic genes (Stra8, Tcfl5, Sycp3, and E2f2) possess open chromatin status already at the mitotic stage together with other features of TCFL5 (potential capability to interact with core TFs and activate meiotic genes, its progressive activation after preleptotene, binding sites in the promoter region of E2f2 and Sycp3), indicated extensive amplification of transcriptional programs associated to mitotic/meiotic switch with an important contribution of TCFL5. We conclude that the identified TFs, are involved in various stages of the mitotic/meiotic switch in female germ cells, TCFL5 primarily in meiotic progression. Further investigation on these factors might give a significant contribution to unravel the molecular mechanisms of this fundamental process of oogenesis and provide clues about pathologies in women such as primary ovarian insufficiency (POI) due at least in part to meiotic defects
Rotating biological contactors : a review on main factors affecting performance
Rotating biological contactors (RBCs)
constitute a very unique and superior alternative
for biodegradable matter and nitrogen removal on
account of their feasibility, simplicity of design and
operation, short start-up, low land area requirement,
low energy consumption, low operating and maintenance
cost and treatment efficiency. The present
review of RBCs focus on parameters that affect
performance like rotational speed, organic and
hydraulic loading rates, retention time, biofilm support
media, staging, temperature, influent wastewater
characteristics, biofilm characteristics, dissolved oxygen
levels, effluent and solids recirculation, stepfeeding
and medium submergence. Some RBCs
scale-up and design considerations, operational problems
and comparison with other wastewater treatment
systems are also reported.Fundação para a CiĂȘncia e a Tecnologia (FCT
Transcriptome profiling of rabbit parthenogenetic blastocysts developed under in vivo conditions
Parthenogenetic embryos are one attractive alternative as a source of embryonic stem cells, although many aspects related to the biology of parthenogenetic embryos and parthenogenetically derived cell lines still need to be elucidated. The present work was conducted to investigate the gene expression profile of rabbit parthenote embryos cultured under in vivo conditions using microarray analysis. Transcriptomic profiles indicate 2541 differentially expressed genes between parthenotes and normal in vivo fertilised blastocysts, of which 76 genes were upregulated and 16 genes downregulated in in vivo cultured parthenote blastocyst, using 3 fold-changes as a cut-off. While differentially upregulated expressed genes are related to transport and protein metabolic process, downregulated expressed genes are related to DNA and RNA binding. Using microarray data, 6 imprinted genes were identified as conserved among rabbits, humans and mice: GRB10, ATP10A, ZNF215, NDN, IMPACT and SFMBT2. We also found that 26 putative genes have at least one member of that gene family imprinted in other species. These data strengthen the view that a large fraction of genes is differentially expressed between parthenogenetic and normal embryos cultured under the same conditions and offer a new approach to the identification of imprinted genes in rabbit. © 2012 Naturil-Alfonso et al.This work was supported by Generalitat Valenciana research programme (Prometeo 2009/125). Carmen Naturil was supported by Generalitat Valenciana research programme (Prometeo 2009/125). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Naturil Alfonso, C.; Saenz De Juano Ribes, MDLD.; Peñaranda, D.; Vicente Antón, JS.; Marco Jiménez, F. (2012). Transcriptome profiling of rabbit parthenogenetic blastocysts developed under in vivo conditions. PLoS ONE. 7(12):1-11. https://doi.org/10.1371/journal.pone.0051271S111712Harness, J. V., Turovets, N. A., Seiler, M. J., Nistor, G., Altun, G., Agapova, L. S., ⊠Keirstead, H. S. (2011). Equivalence of Conventionally-Derived and Parthenote-Derived Human Embryonic Stem Cells. PLoS ONE, 6(1), e14499. doi:10.1371/journal.pone.0014499Lu, Z., Zhu, W., Yu, Y., Jin, D., Guan, Y., Yao, R., ⊠Zhou, Q. (2010). Derivation and long-term culture of human parthenogenetic embryonic stem cells using human foreskin feeders. Journal of Assisted Reproduction and Genetics, 27(6), 285-291. doi:10.1007/s10815-010-9408-5Koh, C. J., Delo, D. M., Lee, J. W., Siddiqui, M. M., Lanza, R. P., Soker, S., ⊠Atala, A. (2009). Parthenogenesis-derived multipotent stem cells adapted for tissue engineering applications. Methods, 47(2), 90-97. doi:10.1016/j.ymeth.2008.08.002Vrana, K. E., Hipp, J. D., Goss, A. M., McCool, B. A., Riddle, D. R., Walker, S. J., ⊠Cibelli, J. B. (2003). Nonhuman primate parthenogenetic stem cells. Proceedings of the National Academy of Sciences, 100(Supplement 1), 11911-11916. doi:10.1073/pnas.2034195100Chen, Z., Liu, Z., Huang, J., Amano, T., Li, C., Cao, S., ⊠Liu, L. (2009). Birth of Parthenote Mice Directly from Parthenogenetic Embryonic Stem Cells. Stem Cells, 27(9), 2136-2145. doi:10.1002/stem.158Sritanaudomchai, H., Ma, H., Clepper, L., Gokhale, S., Bogan, R., Hennebold, J., ⊠Mitalipov, S. (2010). Discovery of a novel imprinted gene by transcriptional analysis of parthenogenetic embryonic stem cells. Human Reproduction, 25(8), 1927-1941. doi:10.1093/humrep/deq144Fang, Z. F., Gai, H., Huang, Y. Z., Li, S. G., Chen, X. J., Shi, J. J., ⊠Sheng, H. Z. (2006). Rabbit embryonic stem cell lines derived from fertilized, parthenogenetic or somatic cell nuclear transfer embryos. Experimental Cell Research, 312(18), 3669-3682. doi:10.1016/j.yexcr.2006.08.013Wang, S., Tang, X., Niu, Y., Chen, H., Li, B., Li, T., ⊠Ji, W. (2007). Generation and Characterization of Rabbit Embryonic Stem Cells. Stem Cells, 25(2), 481-489. doi:10.1634/stemcells.2006-0226Piedrahita, J. A., Anderson, G. B., & BonDurant, R. H. (1990). On the isolation of embryonic stem cells: Comparative behavior of murine, porcine and ovine embryos. Theriogenology, 34(5), 879-901. doi:10.1016/0093-691x(90)90559-cNaturil-Alfonso, C., Saenz-de-Juano, M. D., Peñaranda, D. S., Vicente, J. S., & Marco-Jiménez, F. (2011). Parthenogenic blastocysts cultured under in vivo conditions exhibit proliferation and differentiation expression genes similar to those of normal embryos. Animal Reproduction Science, 127(3-4), 222-228. doi:10.1016/j.anireprosci.2011.08.005Besenfelder, U., Strouhal, C., & Brem, G. (1998). A Method for Endoscopic Embryo Collection and Transfer in the Rabbit. Journal of Veterinary Medicine Series A, 45(1-10), 577-579. doi:10.1111/j.1439-0442.1998.tb00861.xMehaisen, G. M. K., Viudes-de-Castro, M. P., Vicente, J. S., & Lavara, R. (2006). In vitro and in vivo viability of vitrified and non-vitrified embryos derived from eCG and FSH treatment in rabbit does. Theriogenology, 65(7), 1279-1291. doi:10.1016/j.theriogenology.2005.08.007Bilodeau-Goeseels, S., & Schultz, G. A. (1997). Changes in Ribosomal Ribonucleic Acid Content Within in Vitro-produced Bovine Embryos1. Biology of Reproduction, 56(5), 1323-1329. doi:10.1095/biolreprod56.5.1323Conesa, A., Gotz, S., Garcia-Gomez, J. M., Terol, J., Talon, M., & Robles, M. (2005). Blast2GO: a universal tool for annotation, visualization and analysis in functional genomics research. Bioinformatics, 21(18), 3674-3676. doi:10.1093/bioinformatics/bti610Edgar, R. (2002). Gene Expression Omnibus: NCBI gene expression and hybridization array data repository. Nucleic Acids Research, 30(1), 207-210. doi:10.1093/nar/30.1.207Weltzien, F.-A., Pasqualini, C., Vernier, P., & Dufour, S. (2005). A quantitative real-time RT-PCR assay for European eel tyrosine hydroxylase. General and Comparative Endocrinology, 142(1-2), 134-142. doi:10.1016/j.ygcen.2004.12.019Llobat, L., Marco-Jiménez, F., Peñaranda, D., Saenz-de-Juano, M., & Vicente, J. (2011). Effect of Embryonic Genotype on Reference Gene Selection for RT-qPCR Normalization. Reproduction in Domestic Animals, 47(4), 629-634. doi:10.1111/j.1439-0531.2011.01934.xLiu, N., Enkemann, S. A., Liang, P., Hersmus, R., Zanazzi, C., Huang, J., ⊠Liu, L. (2010). Genome-wide Gene Expression Profiling Reveals Aberrant MAPK and Wnt Signaling Pathways Associated with Early Parthenogenesis. Journal of Molecular Cell Biology, 2(6), 333-344. doi:10.1093/jmcb/mjq029Abdoon, A. S., Ghanem, N., Kandil, O. M., Gad, A., Schellander, K., & Tesfaye, D. (2012). cDNA microarray analysis of gene expression in parthenotes and in vitro produced buffalo embryos. Theriogenology, 77(6), 1240-1251. doi:10.1016/j.theriogenology.2011.11.004Labrecque, R., & Sirard, M.-A. (2011). Gene expression analysis of bovine blastocysts produced by parthenogenic activation or fertilisation. Reproduction, Fertility and Development, 23(4), 591. doi:10.1071/rd10243Rizos, D., Clemente, M., Bermejo-Alvarez, P., de La Fuente, J., Lonergan, P., & Gutiérrez-Adån, A. (2008). Consequences ofIn VitroCulture Conditions on Embryo Development and Quality. Reproduction in Domestic Animals, 43, 44-50. doi:10.1111/j.1439-0531.2008.01230.xLonergan, P., Rizos, D., Kanka, J., Nemcova, L., Mbaye, A., Kingston, M., ⊠Boland, M. (2003). Temporal sensitivity of bovine embryos to culture environment after fertilization and the implications for blastocyst quality. Reproduction, 337-346. doi:10.1530/rep.0.1260337Memili, E., & First, N. L. (2000). Zygotic and embryonic gene expression in cow: a review of timing and mechanisms of early gene expression as compared with other species. Zygote, 8(1), 87-96. doi:10.1017/s0967199400000861Latham, K. E. (2001). Embryonic genome activation. Frontiers in Bioscience, 6(3), d748-759. doi:10.2741/a639Niemann, H., & Wrenzycki, C. (2000). Alterations of expression of developmentally important genes in preimplantation bovine embryos by in vitro culture conditions: Implications for subsequent development. Theriogenology, 53(1), 21-34. doi:10.1016/s0093-691x(99)00237-xCorcoran, D., Fair, T., Park, S., Rizos, D., Patel, O. V., Smith, G. W., ⊠Lonergan, P. (2006). Suppressed expression of genes involved in transcription and translation in in vitro compared with in vivo cultured bovine embryos. Reproduction, 131(4), 651-660. doi:10.1530/rep.1.01015Morison, I. M., Ramsay, J. P., & Spencer, H. G. (2005). A census of mammalian imprinting. Trends in Genetics, 21(8), 457-465. doi:10.1016/j.tig.2005.06.008Bischoff, S. R., Tsai, S., Hardison, N., Motsinger-Reif, A. A., Freking, B. A., Nonneman, D., ⊠Piedrahita, J. A. (2009). Characterization of Conserved and Nonconserved Imprinted Genes in Swine1. Biology of Reproduction, 81(5), 906-920. doi:10.1095/biolreprod.109.078139Cruz-Correa, M., Zhao, R., Oveido, M., Bernabe, R. D., Lacourt, M., Cardona, A., ⊠Giardiello, F. M. (2009). Temporal stability and age-related prevalence of loss of imprinting of the insulin-like growth factor-2 gene. Epigenetics, 4(2), 114-118. doi:10.4161/epi.4.2.7954Park, C.-H., Uh, K.-J., Mulligan, B. P., Jeung, E.-B., Hyun, S.-H., Shin, T., ⊠Lee, C.-K. (2011). Analysis of Imprinted Gene Expression in Normal Fertilized and Uniparental Preimplantation Porcine Embryos. PLoS ONE, 6(7), e22216. doi:10.1371/journal.pone.0022216Thurston, A., Taylor, J., Gardner, J., Sinclair, K. D., & Young, L. E. (2007). Monoallelic expression of nine imprinted genes in the sheep embryo occurs after the blastocyst stage. Reproduction, 135(1), 29-40. doi:10.1530/rep-07-0211Li, Y., & Sasaki, H. (2011). Genomic imprinting in mammals: its life cycle, molecular mechanisms and reprogramming. Cell Research, 21(3), 466-473. doi:10.1038/cr.2011.15Mamo, S., Gal, A., Polgar, Z., & Dinnyes, A. (2008). Expression profiles of the pluripotency marker gene POU5F1 and validation of reference genes in rabbit oocytes and preimplantation stage embryos. BMC Molecular Biology, 9(1), 67. doi:10.1186/1471-2199-9-67Navarrete Santos, A., Tonack, S., Kirstein, M., Pantaleon, M., Kaye, P., & Fischer, B. (2004). Insulin acts via mitogen-activated protein kinase phosphorylation in rabbit blastocysts. Reproduction, 128(5), 517-526. doi:10.1530/rep.1.0020
Integrated mapping of pharmacokinetics and pharmacodynamics in a patient-derived xenograft model of glioblastoma
Therapeutic options for the treatment of glioblastoma remain inadequate despite concerted research efforts in drug development. Therapeutic failure can result from poor permeability of the blood-brain barrier, heterogeneous drug distribution, and development of resistance. Elucidation of relationships among such parameters could enable the development of predictive models of drug response in patients and inform drug development. Complementary analyses were applied to a glioblastoma patient-derived xenograft model in order to quantitatively map distribution and resulting cellular response to the EGFR inhibitor erlotinib. Mass spectrometry images of erlotinib were registered to histology and magnetic resonance images in order to correlate drug distribution with tumor characteristics. Phosphoproteomics and immunohistochemistry were used to assess protein signaling in response to drug, and integrated with transcriptional response using mRNA sequencing. This comprehensive dataset provides simultaneous insight into pharmacokinetics and pharmacodynamics and indicates that erlotinib delivery to intracranial tumors is insufficient to inhibit EGFR tyrosine kinase signaling.National Institutes of Health (U.S.) (U54 CA210180)MIT/Mayo Physical Sciences Center for Drug Distribution and Drug Efficacy in Brain TumorsDana-Farber Cancer Institute (PLGA Fund)Lundbeck FoundationNovo Nordisk Foundatio
Conditional corticotropin-releasing hormone overexpression in the mouse forebrain enhances rapid eye movement sleep
Impaired sleep and enhanced stress hormone secretion are the hallmarks of stress-related disorders, including major depression. The central neuropeptide, corticotropin-releasing hormone (CRH), is a key hormone that regulates humoral and behavioral adaptation to stress. Its prolonged hypersecretion is believed to play a key role in the development and course of depressive symptoms, and is associated with sleep impairment. To investigate the specific effects of central CRH overexpression on sleep, we used conditional mouse mutants that overexpress CRH in the entire central nervous system (CRH-COE-Nes) or only in the forebrain, including limbic structures (CRH-COE-Cam). Compared with wild-type or control mice during baseline, both homozygous CRH-COE-Nes and -Cam mice showed constantly increased rapid eye movement (REM) sleep, whereas slightly suppressed non-REM sleep was detected only in CRH-COE-Nes mice during the light period. In response to 6-h sleep deprivation, elevated levels of REM sleep also became evident in heterozygous CRH-COE-Nes and -Cam mice during recovery, which was reversed by treatment with a CRH receptor type 1 (CRHR1) antagonist in heterozygous and homozygous CRH-COE-Nes mice. The peripheral stress hormone levels were not elevated at baseline, and even after sleep deprivation they were indistinguishable across genotypes. As the stress axis was not altered, sleep changes, in particular enhanced REM sleep, occurring in these models are most likely induced by the forebrain CRH through the activation of CRHR1. CRH hypersecretion in the forebrain seems to drive REM sleep, supporting the notion that enhanced REM sleep may serve as biomarker for clinical conditions associated with enhanced CRH secretion
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at â s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fbâ1 of â s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
Search for pair-produced long-lived neutral particles decaying to jets in the ATLAS hadronic calorimeter in ppcollisions at âs=8TeV
The ATLAS detector at the Large Hadron Collider at CERN is used to search for the decay of a scalar boson to a pair of long-lived particles, neutral under the Standard Model gauge group, in 20.3fbâ1of data collected in protonâproton collisions at âs=8TeV. This search is sensitive to long-lived particles that decay to Standard Model particles producing jets at the outer edge of the ATLAS electromagnetic calorimeter or inside the hadronic calorimeter. No significant excess of events is observed. Limits are reported on the product of the scalar boson production cross section times branching ratio into long-lived neutral particles as a function of the proper lifetime of the particles. Limits are reported for boson masses from 100 GeVto 900 GeV, and a long-lived neutral particle mass from 10 GeVto 150 GeV
Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at sâ=8 TeV with the ATLAS detector
The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1fbâ1 of protonâproton collision data at âs = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via tËâtÏË01 or tËâ bÏ˱1 âbW(â)ÏË01 , where ÏË01 (Ï˱1 ) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of tË â tÏË01 . For a branching fraction of 100%, top squark masses in the range 270â645 GeV are excluded for ÏË01 masses below 30 GeV. For a branching fraction of 50% to either tË â tÏË01 or tË â bÏ˱1 , and assuming the Ï˱1 mass to be twice the ÏË01 mass, top squark masses in the range 250â550 GeV are excluded for ÏË01 masses below 60 GeV
Observation of associated near-side and away-side long-range correlations in âsNN=5.02ââTeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (ÎÏ) and pseudorapidity (Îη) are measured in âsNN=5.02ââTeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1ââÎŒb-1 of data as a function of transverse momentum (pT) and the transverse energy (ÎŁETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Îη|<5) ânear-sideâ (ÎÏâŒ0) correlation that grows rapidly with increasing ÎŁETPb. A long-range âaway-sideâ (ÎÏâŒÏ) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ÎŁETPb, is found to match the near-side correlation in magnitude, shape (in Îη and ÎÏ) and ÎŁETPb dependence. The resultant ÎÏ correlation is approximately symmetric about Ï/2, and is consistent with a dominant cosâĄ2ÎÏ modulation for all ÎŁETPb ranges and particle pT
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