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201.
Wuelton M Monteiro Fernando FA Val André M Siqueira Gabriel P Franca Vanderson S Sampaio Gisely C Melo Anne CG Almeida Marcelo AM Brito Henry M Peixoto Douglas Fuller Quique Bassat Gustavo AS Romero Oliveira Maria Regina F Lacerda Marcus Vinícius G 《Memórias do Instituto Oswaldo Cruz》2014,109(5):553-568
202.
Linda Spiegelberg Sigrid MA Swagemakers Wilfred FJ van IJcken Edwin Oole Eppo B Wolvius Jeroen Essers Joanna AM Braks 《Molecular medicine (Cambridge, Mass.)》2014,20(1):257-269
A side effect of radiation therapy in the head and neck region is injury to surrounding healthy tissues such as irreversible impaired function of the salivary glands. Hyperbaric oxygen therapy (HBOT) is clinically used to treat radiation-induced damage but its mechanism of action is largely unknown. In this study, we investigated the molecular pathways that are affected by HBOT in mouse salivary glands two weeks after radiation therapy by microarray analysis. Interestingly, HBOT led to significant attenuation of the radiation-induced expression of a set of genes and upstream regulators that are involved in processes such as fibrosis and tissue regeneration. Our data suggest that the TGFβ-pathway, which is involved in radiation-induced fibrosis and chronic loss of function after radiation therapy, is affected by HBOT. On the longer term, HBOT reduced the expression of the fibrosis-associated factor α-smooth muscle actin in irradiated salivary glands. This study highlights the potential of HBOT to inhibit the TGFβ-pathway in irradiated salivary glands and to restrain consequential radiation induced tissue injury. 相似文献
203.
Herwin Eding Richard PMA Crooijmans Martien AM Groenen Theo HE Meuwissen 《遗传、选种与进化》2002,34(5):613-633
The quantitative assessment of genetic diversity within and between populations is important for decision making in genetic conservation plans. In this paper we define the genetic diversity of a set of populations, S, as the maximum genetic variance that can be obtained in a random mating population that is bred from the set of populations S. First we calculated the relative contribution of populations to a core set of populations in which the overlap of genetic diversity was minimised. This implies that the mean kinship in the core set should be minimal. The above definition of diversity differs from Weitzman diversity in that it attempts to conserve the founder population (and thus minimises the loss of alleles), whereas Weitzman diversity favours the conservation of many inbred lines. The former is preferred in species where inbred lines suffer from inbreeding depression. The application of the method is illustrated by an example involving 45 Dutch poultry breeds. The calculations used were easy to implement and not computer intensive. The method gave a ranking of breeds according to their contributions to genetic diversity. Losses in genetic diversity ranged from 2.1% to 4.5% for different subsets relative to the entire set of breeds, while the loss of founder genome equivalents ranged from 22.9% to 39.3%. 相似文献
204.
BLM and SLX4 play opposing roles in recombination‐dependent replication at human telomeres
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Alexander P Sobinoff Joshua AM Allen Axel A Neumann Sile F Yang Monica E Walsh Jeremy D Henson Roger R Reddel Hilda A Pickett 《The EMBO journal》2017,36(19):2907-2919
Alternative lengthening of telomeres (ALT) is a telomere lengthening pathway that predominates in aggressive tumors of mesenchymal origin; however, the underlying mechanism of telomere synthesis is not fully understood. Here, we show that the BLM–TOP3A–RMI (BTR) dissolvase complex is required for ALT‐mediated telomere synthesis. We propose that recombination intermediates formed during strand invasion are processed by the BTR complex, initiating rapid and extensive POLD3‐dependent telomere synthesis followed by dissolution, with no overall exchange of telomeric DNA. This process is counteracted by the SLX4–SLX1–ERCC4 complex, which promotes resolution of the recombination intermediate, resulting in telomere exchange in the absence of telomere extension. Our data are consistent with ALT being a conservative DNA replication process, analogous to break‐induced replication, which is dependent on BTR and counteracted by SLX4 complex‐mediated resolution events. 相似文献
205.
Visualization of cytosolic ribosomes on the surface of mitochondria by electron cryo‐tomography
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We employed electron cryo‐tomography to visualize cytosolic ribosomes on the surface of mitochondria. Translation‐arrested ribosomes reveal the clustered organization of the TOM complex, corroborating earlier reports of localized translation. Ribosomes are shown to interact specifically with the TOM complex, and nascent chain binding is crucial for ribosome recruitment and stabilization. Ribosomes are bound to the membrane in discrete clusters, often in the vicinity of the crista junctions. This interaction highlights how protein synthesis may be coupled with transport. Our work provides unique insights into the spatial organization of cytosolic ribosomes on mitochondria. 相似文献
206.
The anti-algal activity of five macrophyte extracts on the cyanobacterium Microcystis aeruginosa in Egypt was investigated in 2013. Extract activity varied according to plant type, extracting solvent and its concentration. The highest inhibitory activity was achieved with ethanol extract at a concentration of 80 mg l?1, followed by chloroformic extracts, at 60 mg l?1. Methanolic extracts of Eichhornia crassipes and Polygonum tomentosum inhibited growth of Microcystis aeruginosa at all concentrations. Acetonic extracts inhibited algal growth at 60 mg l?1, except for the extract of Ceratophyllum subdemersum, which showed stimulation of M. aeruginosa growth. Eichhornia crassipes ethanolic extract exerted the most powerful inhibition by more than five-fold, 570.17%, followed by those of P. tomentosum, Saccharum spontaneum, Ceratophyllum demersum and C. subdemersum, 559.48, 553.99, 544.11 and 366.51%, respectively. Phytochemical screening for the tested plant extracts revealed the presence of biologically active substances of different concentrations, with P. tomentosum having the highest polyphenols, 1.95% of dry weight. 相似文献
207.
Danyel GJ Jennen Addie LJ Vereijken Henk Bovenhuis Richard MPA Crooijmans Jan J van der Poel Martien AM Groenen 《遗传、选种与进化》2005,37(3):215-228
In this report we describe the analysis of an advanced intercross line (AIL) to confirm the quantitative trait locus (QTL) regions found for fatness traits in a previous study. QTL analysis was performed on chromosomes 1, 3, 4, 15, 18, and 27. The AIL was created by random intercrossing in each generation from generation 2 (G2) onwards until generation 9 (G9) was reached. QTL for abdominal fat weight (AFW) and/or percentage abdominal fat (AF%) on chromosomes 1, 3 and 27 were confirmed in the G9 population. In addition, evidence for QTL for body weight at the age of 5 (BW5) and 7 (BW7) weeks and for the percentage of intramuscular fat (IF%) were found on chromosomes 1, 3, 15, and 27. Significant evidence for QTL was detected on chromosome 1 for BW5 and BW7. Suggestive evidence was found on chromosome 1 for AFW, AF% and IF%, on chromosome 15 for BW5, and on chromosome 27 for AF% and IF%. Furthermore, evidence on the chromosome-wise level was found on chromosome 3 for AFW, AF%, and BW7 and on chromosome 27 for BW5. For chromosomes 4 and 18, test statistics did not exceed the significance threshold. 相似文献
208.
209.
Petra Mlcochova Katherine A Sutherland Sarah A Watters Cosetta Bertoli Rob AM de Bruin Jan Rehwinkel Stuart J Neil Gina M Lenzi Baek Kim Asim Khwaja Matthew C Gage Christiana Georgiou Alexandra Chittka Simon Yona Mahdad Noursadeghi Greg J Towers Ravindra K Gupta 《The EMBO journal》2017,36(5):604-616
An unresolved question is how HIV‐1 achieves efficient replication in terminally differentiated macrophages despite the restriction factor SAMHD1. We reveal inducible changes in expression of cell cycle‐associated proteins including MCM2 and cyclins A, E, D1/D3 in macrophages, without evidence for DNA synthesis or mitosis. These changes are induced by activation of the Raf/MEK/ERK kinase cascade, culminating in upregulation of CDK1 with subsequent SAMHD1 T592 phosphorylation and deactivation of its antiviral activity. HIV infection is limited to these G1‐like phase macrophages at the single‐cell level. Depletion of SAMHD1 in macrophages decouples the association between infection and expression of cell cycle‐associated proteins, with terminally differentiated macrophages becoming highly susceptible to HIV‐1. We observe both embryo‐derived and monocyte‐derived tissue‐resident macrophages in a G1‐like phase at frequencies approaching 20%, suggesting how macrophages sustain HIV‐1 replication in vivo. Finally, we reveal a SAMHD1‐dependent antiretroviral activity of histone deacetylase inhibitors acting via p53 activation. These data provide a basis for host‐directed therapeutic approaches aimed at limiting HIV‐1 burden in macrophages that may contribute to curative interventions. 相似文献
210.