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61.
Karyotypes of two continuous Chinese hamster cell lines CHO-K1 and V-79 were studied by G-banding and silver staining. Modal chromosome numbers were 20 and 21, respectively. Both the lines were characterized with a high degree of karyotype stability and constant ratio of normal and marker chromosomes. Nulli- and monosomy were recorded for 9 chromosome pairs in CHO-K1, and 8 pairs in V-79 cell lines. Modal numbers of Ag-positive NOR were 4 in CHO-K1 and 5 in V-79. A definition of the origin of the majority of marker chromosomes in both the lines (11 and 10, respectively) made it possible to establish the exact chromosome content of each cell and to determine the generalized reconstructed karyotypes of cell lines. We established the retention of diploid chromosome set of all the autosomes, the true monosomy for one X-chromosome in both the lines, and the constant extracopying of a short arm of chromosome 3 in the V-79 cell line. 相似文献
62.
Oxana A. Kovaleva Vladimir B. Tsvetkov Olga K. Mamaeva Valentina A. Ol’shevskaya Anton V. Makarenkov Lyubov G. Dezhenkova Alexander S. Semeikin Olga F. Borisova Alexander A. Shtil Anna K. Shchyolkina Dmitry N. Kaluzhny 《European biophysics journal : EBJ》2014,43(10-11):545-554
The porphyrin-based photosensitizers capable of binding to DNA are perspective drug candidates. Here we report the interactions with calf thymus DNA of 5,10,15,20-tetrakis(N-carboxymethyl-4-pyridinium)porphyrin (P1) and its derivatives containing Zn(II) or Ni(II) in the coordination sphere. These interactions were studied with absorption and circular dichroism spectroscopy. NiP1 and ZnP1 formed different types of complexes with DNA. NiP1 intercalated into the double helix, whereas ZnP1 bound the DNA groove. Compound P1 displayed both binding modes. The ZnP1-DNA binding constant was approximately three times smaller than the respective values for P1-DNA and NiP1-DNA complexes. Light induced degradation of the reactive oxygen species (ROS) trap 1,3-diphenylisobenzofuran in the presence of P1 and its metal derivatives revealed that NiP1 was a weaker photooxidative agent, whereas P1 and ZnP1 generated ROS to similar extents. Nevertheless, the DNA photodamaging effect of ZnP1 was the most pronounced. Illumination of the supercoiled plasmid caused single-strand DNA photocleavage in the presence of P1 and ZnP1; double strand breaks were detectable with micromolar concentrations of ZnP1. The concentration of ZnP1 required for plasmid photonicking was two times smaller than that of P1 and ~20 times lower than that for NiP1. Thus, the modes of P1, NiP1 and ZnP1 binding to DNA determine the differential photodamaging potency of these porphyrins. A greater accessibility to the solvent of the groove binder ZnP1, compared to the shielded intercalator NiP1 and the intercalated P1 molecules, allows for an efficient local generation of ROS followed by DNA photocleavage. 相似文献
63.
64.
Muscle-derived stem cells isolated as non-adherent population give rise to cardiac, skeletal muscle and neural lineages 总被引:5,自引:0,他引:5
Stem cells with the ability to differentiate in specialized cell types can be extracted from a wide array of adult tissues including skeletal muscle. Here we have analyzed a population of cells isolated from skeletal muscle on the basis of their poor adherence on uncoated or collagen-coated dishes that show multi-lineage differentiation in vitro. When analysed under proliferative conditions, these cells express stem cell surface markers Sca-1 (65%) and Bcrp-1 (80%) but also MyoD (15%), Neuronal beta III-tubulin (25%), GFAP (30%) or Nkx2.5 (1%). Although capable of growing as non-attached spheres for months, when given an appropriate matrix, these cells adhere giving rise to skeletal muscle, neuronal and cardiac muscle cell lineages. A similar cell population could not be isolated from either bone marrow or cardiac tissue suggesting their specificity to skeletal muscle. When injected into damaged muscle, these non-adherent muscle-derived cells are retrieved expressing Pax7, in a sublaminar position characterizing satellite cells and participate in forming new myofibers. These data show that a non-adherent stem cell population can be specifically isolated and expanded from skeletal muscle and upon attachment to a matrix spontaneously differentiate into muscle, cardiac and neuronal lineages in vitro. Although competing with resident satellite cells, these cells are shown to significantly contribute to repair of injured muscle in vivo supporting that a similar muscle-derived non-adherent cell population from human muscle may be useful in treatment of neuromuscular disorders. 相似文献
65.
L V Filatov S E Mamaeva N V Tomilin 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1988,(11):41-45
The dispersion of the Alu-family DNA repeats in phytohemagglutinin-stimulated lymphocytes from peripheral blood of normal donors as well as in nonstimulated bone marrow cells of four patients suffering from acute leukemia was studied by hybridization on metaphase chromosomes in situ. DNA of bacteriophage lambda CAR42 clone containing the insertion of at least 8 copies of Alu-family DNA-repeats and labelled with tritium was used as a probe in hybridization. All patients with acute leukemia had the same pattern of changes in hybridization of the bone marrow cells. It consists of silver grains clustering over 3q26, 8p12, 14q24. The pattern may reflect amplification transposition of Alu-family DNA repeats in the human genome connected with cellular differentiation or malignant transformation of blood cells. 相似文献
66.
Primary structure of the gene for VP1 protein of the foot-and-mouth disease virus of Asia 1 serotype
S V Sosnovtsev A M Onishchenko N A Petrov N V Mamaeva T I Kalashnikova N A Perevozchikova V N Ivaniushchenkov A N Burdov S K Vasilenko 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1989,(12):44-46
The nucleotide sequence of the cDNA for the viral RNA region coding for the main antigenic protein of the epidemic stomatitis virus of Asia 1 serotype has been identified. The amino acid sequences in the regions of VP1 protein antigenic determinants of the serotype Asia 1 virus and other serotypes viruses have been compared. 相似文献
67.
68.
Role of planktonic bacteria in productivity and cycling of organic matter in the Eastern Pacific Ocean 总被引:1,自引:1,他引:0
Total number, biomass, production, and respiration of bacterioplankton were measured in oligotrophic, mesotrophic and eutrophic waters of the Eastern Pacific. Total number of bacteria in the upper mixed layer and in the upper thermocline boundary layers varied from 30–60.103 ml-1 in oligotrophic waters to 100–400.103 ml-1 in mesotrophic waters of fronts and divergences, and to 1–2,5.106 ml-1 in eutrophic waters of coastal upwellings. Wet biomass varied from 5–10 mg l-1 in oligotrophic waters, to 50–200 mg l-1 in mesotrophic waters, and to 1–2 g m-3 in eutrophic waters. Below the layer of maximum temperature gradient i.e. below 35–50 m, bacterioplankton density decreased 5–10 times. P/B coefficients per day were highest in the oligotrophic surface water ( 1), and lowest in the eutrophic ones (0.2–0.4). In mesotrophic waters they were intermediate (0.4–1.0). the stock of labile organic matter (LOM) accessible to microbial action varied from 0.3 to 1.6 mg Cl-1. Its highest value occurred in the upwelling area. The stock of LOM does not noticeably decrease from the euphotic zone to a depth of 2 000 m. Its turnover time varied from 5 to 45 days in surface waters, and 30–50 years in deep oceanic waters. The role of bacterioplankton in productivity and in cycling of organic matter in surface — and deep oceanic waters is discussed. 相似文献
69.
Frank Rutsch Mary MacDougall Changming Lu Insa Buers Olga Mamaeva Yvonne Nitschke Gillian?I. Rice Heidi Erlandsen Hans?Gerd Kehl Holger Thiele Peter Nürnberg Wolfgang H?hne Yanick?J. Crow Annette Feigenbaum Raoul?C. Hennekam 《American journal of human genetics》2015,96(2):275-282
Singleton-Merten syndrome (SMS) is an infrequently described autosomal-dominant disorder characterized by early and extreme aortic and valvular calcification, dental anomalies (early-onset periodontitis and root resorption), osteopenia, and acro-osteolysis. To determine the molecular etiology of this disease, we performed whole-exome sequencing and targeted Sanger sequencing. We identified a common missense mutation, c.2465G>A (p.Arg822Gln), in interferon induced with helicase C domain 1 (IFIH1, encoding melanoma differentiation-associated protein 5 [MDA5]) in four SMS subjects from two families and a simplex case. IFIH1 has been linked to a number of autoimmune disorders, including Aicardi-Goutières syndrome. Immunohistochemistry demonstrated the localization of MDA5 in all affected target tissues. In vitro functional analysis revealed that the IFIH1 c.2465G>A mutation enhanced MDA5 function in interferon beta induction. Interferon signature genes were upregulated in SMS individuals’ blood and dental cells. Our data identify a gain-of-function IFIH1 mutation as causing SMS and leading to early arterial calcification and dental inflammation and resorption. 相似文献
70.
A Bell OA Rodríguez LA de Castro e Paula MB Padua J Hernández-Cerón CG Gutiérrez A De Vries PJ Hansen 《BMC veterinary research》2008,4(1):22