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991.
Mikhail G. Divashuk Oleg S. Alexandrov Olga V. Razumova Ilya V. Kirov Gennady I. Karlov 《PloS one》2014,9(1)
Hemp (Cannabis sativa L.) was karyotyped using by DAPI/C-banding staining to provide chromosome measurements, and by fluorescence in situ hybridization with probes for 45 rDNA (pTa71), 5S rDNA (pCT4.2), a subtelomeric repeat (CS-1) and the Arabidopsis telomere probes. The karyotype has 18 autosomes plus a sex chromosome pair (XX in female and XY in male plants). The autosomes are difficult to distinguish morphologically, but three pairs could be distinguished using the probes. The Y chromosome is larger than the autosomes, and carries a fully heterochromatic DAPI positive arm and CS-1 repeats only on the less intensely DAPI-stained, euchromatic arm. The X is the largest chromosome of all, and carries CS-1 subtelomeric repeats on both arms. The meiotic configuration of the sex bivalent locates a pseudoautosomal region of the Y chromosome at the end of the euchromatic CS-1-carrying arm. Our molecular cytogenetic study of the C. sativa sex chromosomes is a starting point for helping to make C. sativa a promising model to study sex chromosome evolution. 相似文献
992.
993.
Elisa Villa Aleksander S. Alekseev James E. Barrick Darwin R. Boardman Alexandra V. Djenchuraeva Beate Fohrer Holger Forke Natalya V. Goreva Philip H. Heckel Tatiana N. Isakova Olga Kossovaya Lance L. Lambert María-Luisa Martínez-Chacn Carlos A. Mndez Tamara I. Nemyrovska Svetlana Remizova Elias Samankassou Luis C. Snchez de Posada Katsumi Ueno Greg Wahlman David M. Work 《Palaeoworld》2009,18(2-3):114-119
Studies carried out for more than 10 years by the Task Group to establish GSSPs at the base of the Moscovian–Kasimovian and Kasimovian–Gzhelian boundaries have resulted in the proposal that the level at which the conodont species Idiognathodus simulator (Ellison, 1941) first appears be selected to mark the base of the Gzhelian Stage. This expands this eastern European chronostratigraphic unit to a global scale.I. simulator (sensu Barrick et al., 2008) has been identified so far in Midcontinent and eastern North America, the Moscow and Donets basins and southern Urals of eastern Europe, and in south-central China. Correlation of this level based on this species and other conodont species can be reinforced in some areas by ammonoid and fusulinid data. 相似文献
994.
995.
996.
Olga Dolnik Larissa Kolesnikova Sonja Welsch Thomas Strecker Gordian Schudt Stephan Becker 《PLoS pathogens》2014,10(10)
Endosomal sorting complex required for transport (ESCRT) machinery supports the efficient budding of Marburg virus (MARV) and many other enveloped viruses. Interaction between components of the ESCRT machinery and viral proteins is predominantly mediated by short tetrapeptide motifs, known as late domains. MARV contains late domain motifs in the matrix protein VP40 and in the genome-encapsidating nucleoprotein (NP). The PSAP late domain motif of NP recruits the ESCRT-I protein tumor susceptibility gene 101 (Tsg101). Here, we generated a recombinant MARV encoding NP with a mutated PSAP late domain (rMARVPSAPmut). rMARVPSAPmut was attenuated by up to one log compared with recombinant wild-type MARV (rMARVwt), formed smaller plaques and exhibited delayed virus release. Nucleocapsids in rMARVPSAPmut-infected cells were more densely packed inside viral inclusions and more abundant in the cytoplasm than in rMARVwt-infected cells. A similar phenotype was detected when MARV-infected cells were depleted of Tsg101. Live-cell imaging analyses revealed that Tsg101 accumulated in inclusions of rMARVwt-infected cells and was co-transported together with nucleocapsids. In contrast, rMARVPSAPmut nucleocapsids did not display co-localization with Tsg101, had significantly shorter transport trajectories, and migration close to the plasma membrane was severely impaired, resulting in reduced recruitment into filopodia, the major budding sites of MARV. We further show that the Tsg101 interacting protein IQGAP1, an actin cytoskeleton regulator, was recruited into inclusions and to individual nucleocapsids together with Tsg101. Moreover, IQGAP1 was detected in a contrail-like structure at the rear end of migrating nucleocapsids. Down regulation of IQGAP1 impaired release of MARV. These results indicate that the PSAP motif in NP, which enables binding to Tsg101, is important for the efficient actin-dependent transport of nucleocapsids to the sites of budding. Thus, the interaction between NP and Tsg101 supports several steps of MARV assembly before virus fission. 相似文献
997.
Dan P. Zandberg Sandra Rollins Olga Goloubeva Robert E. Morales Ming Tan Rodney Taylor Jeffrey S. Wolf Lisa M. Schumaker Kevin J. Cullen Ann Zimrin Robert Ord Joshua E. Lubek Mohan Suntharalingam John C. Papadimitriou Dean Mann Scott E. Strome Martin J. Edelman 《Cancer immunology, immunotherapy : CII》2015,64(3):367-379
998.
Lidia Poplawska-Szczyglowska Jan Walewski Barbara Pienkowska-Grela Grzegorz Rymkiewicz Olga Mioduszewska 《Cancer immunology, immunotherapy : CII》1999,16(1):65-68
A 68-year-old man presented with hemiparesis, lymphocytosis, and cerebral lesions on MRI. Flow cytometry of blood, bone marrow
and cerebrospinal fluid showed B-CLL lymphocytes with bright CD20 expression, slg, and absence of CD23 antigen. Fluorescencein situ hybridisation showed trisomy 12 in 50% of analysed peripheral mononuclear cells. The patient died 6 months after the diagnosis.
Rapidly progressive and fatal course of the disease was consistent with known bad prognostic significance of CD20 bright expression
and trisomy 12. 相似文献
999.
Olga Bravo Alexis Ferrer Cateryna Aiello Anselmo Ledesma Miguel Dávila 《Biotechnology letters》1994,16(8):865-870
Sugar cane bagasse was water- or alkali-treated at three liquid/solid (L/S) ratios and its digestibility was measured as microbial protein production of Chaetomium cellulolyticum grown on solid-state fermentation columns. The treatments significantly enhanced fungus growth compared to non-treated bagasse, which was used as a control, although the composition of bagasse did not change greatly. Alkali-treated bagasse reached an average protein content of about 7.6% and the lower the L/S ratio, the higher the protein content. L/S ratio did not have an effect in water-treated bagasse. Protein content of water-treated bagasse was also high, approximately 80% of that one of alkali-treated bagasse. Both treatments look promising to enhance sugar cane bagasse potential as an animal feed.Currently at Universidad Francisco de Miranda. Coro, Venezuela.Currently at Ciclo Básico, Facultad de Ingeniería, Universidad del Zulia. Maracaibo, Venezuela. 相似文献
1000.
Evaluation of the fossil fish‐specific diversity in a chadian continental assemblage: Exploration of morphological continuous variation in Synodontis (Ostariophysi,Siluriformes) 下载免费PDF全文
In the fossil record, the quantification of continuous morphological variation has become a central issue when dealing with species identification and speciation. In this context, fossil taxa with living representatives hold great promise, because of the potential to characterise patterns of intraspecific morphological variation in extant species prior to any interpretation in the fossil record. The vast majority of catfish families fulfil this prerequisite, as most of them are represented by extant genera. However, although they constitute a major fish group in terms of distribution, and ecological and taxonomic diversity, the quantitative study of their past morphological variation has been neglected, as fossil specimens are generally identified based on the scarcest remains, that is, complete neurocrania that bear discrete characters. Consequently, a part of freshwater catfish history is unprospected and unknown. In this study, we explored the morphological continuous variation of the humeral plate shape in Synodontis catfishes using Elliptic Fourier Analysis (EFA), and compared extant members and fossil counterparts. We analysed 153 extant specimens of 11 Synodontis species present in the Chad basin, in addition to 23 fossil specimens from the Chadian fossiliferous area of Toros Menalla which is dated around 7 Ma. This highly speciose genus, which is one of the most diversified in Africa, exhibits a rich fossil record with several hundred remains mostly identified as Synodontis sp. The analysis of the outline of the humeral plate reveals that some living morphological types were already represented in the Chad Basin 7 My ago, and allows for the discovery of extinct species. Beside illuminating the complex Neogene evolutionary history of Synodontis, these results underline the interest in the ability of isolated remains to reconstruct a past dynamic history and to validate the relevance of EFA as a tool to explore specific diversity through time. J. Morphol. 277:1486–1496, 2016. © 2016 Wiley Periodicals, Inc. 相似文献