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991.
Ding J Kritchevsky SB Harris TB Burke GL Detrano RC Szklo M Jeffrey Carr J;Multi-Ethnic Study of Atherosclerosis 《Obesity (Silver Spring, Md.)》2008,16(8):1914-1919
Background: Pericardial fat has a higher secretion of inflammatory cytokines than subcutaneous fat. Cytokines released from pericardial fat around coronary arteries may act locally on the adjacent cells. Objective: We examined the relationship between pericardial fat and calcified coronary plaque. Methods and Procedures: Participants in the community‐based Multi‐Ethnic Study of Atherosclerosis (MESA) underwent a computed tomography (CT) scan for the assessment of calcified coronary plaque in 2000/2002. We measured the volume of pericardial fat using these scans in 159 whites and blacks without symptomatic coronary heart disease from Forsyth County, NC, aged 55–74 years. Results: Calcified coronary plaque was observed in 91 participants (57%). After adjusting for height, a 1 s.d. increment in pericardial fat was associated with an increased odds of calcified coronary plaque (odds ratio (95% confidence interval): 1.92 (1.27, 2.90)). With further adjustment of other cardiovascular factors, pericardial fat was still significantly associated with calcified coronary plaque. This relationship did not differ by gender and ethnicity. On the other hand, BMI and height‐adjusted waist circumference were not associated with calcified coronary plaque. Discussion: Pericardial fat is independently associated with calcified coronary plaque. 相似文献
992.
Isadora May Vaz Tamara Borgonovo Tais Hanae Kasai-Brunswick Danúbia Silva dos Santos Fernanda Cristina Paccola Mesquita Juliana Ferreira Vasques Fernanda Gubert Carmen Lúcia Kuniyoshi Rebelatto Alexandra Cristina Senegaglia Paulo Roberto Slud Brofman 《Genetics and molecular biology》2021,44(3)
Induced pluripotent stem cells (iPSCs) are generated from adult cells that have been reprogrammed to pluripotency. However, in vitro cultivation and genetic reprogramming increase genetic instability, which could result in chromosomal abnormalities. Maintenance of genetic stability after reprogramming is required for possible experimental and clinical applications. The aim of this study was to analyze chromosomal alterations by using the G-banding karyotyping method applied to 97 samples from 38 iPSC cell lines generated from peripheral blood or Wharton’s jelly. Samples from patients with long QT syndrome, Jervell and Lange-Nielsen syndrome and amyotrophic lateral sclerosis and from normal individuals revealed the following chromosomal alterations: acentric fragments, chromosomal fusions, premature centromere divisions, double minutes, radial figures, ring chromosomes, polyploidies, inversions and trisomies. An analysis of two samples generated from Wharton’s jelly before and after reprogramming showed that abnormal clones can emerge or be selected and generate an altered lineage. IPSC lines may show clonal and nonclonal chromosomal aberrations in several passages (from P6 to P34), but these aberrations are more common in later passages. Many important chromosomal aberrations were detected, showing that G-banding is very useful for evaluating genetic instability with important repercussions for the application of iPSC lines. 相似文献
993.
994.
Andjelka M. Isakovic Marija Dulovic Ivanka Markovic Tamara Kravic-Stevovic Vladimir Bumbasirevic Vladimir Trajkovic Aleksandra Isakovic 《Experimental cell research》2017,350(1):32-40
We investigated the role of autophagy, a process of controlled self-digestion, in the in vitro anticancer action of the inosine monophosphate dehydrogenase (IMPDH) inhibitor ribavirin. Ribavirin-triggered oxidative stress, caspase activation, and apoptotic death in U251 human glioma cells were associated with the induction of autophagy, as confirmed by intracellular acidification, appearance of autophagic vesicles, conversion of microtubule associated protein 1 light chain 3 (LC3)-I to autophagosome-associated LC3-II, and degradation of autophagic target p62/sequestosome 1. Ribavirin downregulated the activity of autophagy-inhibiting mammalian target of rapamycin complex 1 (mTORC1), as indicated by a decrease in phosphorylation of the mTORC1 substrate ribosomal p70S6 kinase and reduction of the mTORC1-activating Src/Akt signaling. Guanosine supplementation inhibited, while IMPDH inhibitor tiazofurin mimicked ribavirin-mediated autophagy induction, suggesting the involvement of IMPDH blockade in the observed effect. Autophagy suppression by ammonium chloride, bafilomycin A1, or RNA interference-mediated knockdown of LC3 sensitized glioma cells to ribavirin-induced apoptosis. Ribavirin also induced cytoprotective autophagy associated with Akt/mTORC1 inhibition in C6 rat glioma cells. Our data demonstrate that ribavirin-triggered Akt/mTORC1-dependent autophagy counteracts apoptotic death of glioma cells, indicating autophagy suppression as a plausible therapeutic strategy for sensitization of cancer cells to IMPDH inhibition. 相似文献
995.
Maksym Antonyuk Anastasiia Navalikhina Tamara Ternovska 《Journal of applied genetics》2017,58(2):143-149
Variability of the beta-amylase gene in bread wheat, artificial amphidiploids, and derived introgression wheat lines was analyzed. Variation in homeologous beta-amylase sequences caused by the presence of MITE (Miniature Inverted-Repeat Transposable Element) and its footprint has been identified in bread wheat. The previously unknown location of MITE in Triticum urartu and T. aestivum L. beta-amylase gene has been found. These species have a MITE sequence in the third intron of beta-amylase, as opposed to Aegilops comosa and a number of other Triticeae species, which have it in the fourth intron. These two MITEs from Ae. comosa and T. aestivum were shown to have low identity scores. Miosa, an artificial amphidiploid, which has the M genome from Ae. comosa was shown to lose the MITE sequences. This loss might be caused by genomic shock due to allopolyploidization. 相似文献
996.
Richard E. Sparks K. Douglas Blodgett Andrew F. Casper Heath M. Hagy Michael J. Lemke Luiz Felipe Machado Velho Luzia Cleide Rodrigues 《Hydrobiologia》2017,804(1):177-200
The Nature Conservancy’s wetland restoration at the Emiquon Preserve has been a success to date, but there are warning signs of undesirable change if left unmanaged. A water control structure built in 2016 will increase management capabilities, but periodic connection to the river, which has experienced human alterations typical of rivers in eastern North America and Europe, also introduces risks. The Conservancy’s planning process has identified (1) management targets (e.g., diverse native fish populations); (2) Key Ecological Attributes (KEAs) that maintain the targets (e.g., relatively deep over-wintering habitats for fishes); (3) measurable indicators for the KEAs (e.g., depth in winter); and (4) desirable ranges for the indicators (e.g., 10% of the aquatic area has depths of 2–3 m and dissolved oxygen levels of 4–6 mg/l). Assessments and experiments completed to date have focused on documenting the restoration, evaluating effects of the record flood of 2013, and predicting outcomes of management actions. Simulation models of hydrology, hydraulics, and vegetation response developed during the planning process allayed some concerns of stakeholders, but not all outcomes are predictable from either current theory or management experience. Therefore, each action can be considered not only as an adaptive management experiment focused on sustaining targets, but also contributing to ecological theory and restoration practice on a broader scale. 相似文献
997.
The ANGULATA7 gene encodes a DnaJ‐like zinc finger‐domain protein involved in chloroplast function and leaf development in Arabidopsis 下载免费PDF全文
Tamara Muñoz‐Nortes José Manuel Pérez‐Pérez María Rosa Ponce Héctor Candela José Luis Micol 《The Plant journal : for cell and molecular biology》2017,89(5):870-884
The characterization of mutants with altered leaf shape and pigmentation has previously allowed the identification of nuclear genes that encode plastid‐localized proteins that perform essential functions in leaf growth and development. A large‐scale screen previously allowed us to isolate ethyl methanesulfonate‐induced mutants with small rosettes and pale green leaves with prominent marginal teeth, which were assigned to a phenotypic class that we dubbed Angulata. The molecular characterization of the 12 genes assigned to this phenotypic class should help us to advance our understanding of the still poorly understood relationship between chloroplast biogenesis and leaf morphogenesis. In this article, we report the phenotypic and molecular characterization of the angulata7‐1 (anu7‐1) mutant of Arabidopsis thaliana, which we found to be a hypomorphic allele of the EMB2737 gene, which was previously known only for its embryonic‐lethal mutations. ANU7 encodes a plant‐specific protein that contains a domain similar to the central cysteine‐rich domain of DnaJ proteins. The observed genetic interaction of anu7‐1 with a loss‐of‐function allele of GENOMES UNCOUPLED1 suggests that the anu7‐1 mutation triggers a retrograde signal that leads to changes in the expression of many genes that normally function in the chloroplasts. Many such genes are expressed at higher levels in anu7‐1 rosettes, with a significant overrepresentation of those required for the expression of plastid genome genes. Like in other mutants with altered expression of plastid‐encoded genes, we found that anu7‐1 exhibits defects in the arrangement of thylakoidal membranes, which appear locally unappressed. 相似文献
998.
Population history and life history influence the migration rate of female Glanville fritillary butterflies 总被引:4,自引:0,他引:4
Ilkka Hanski Casper J. Breuker Katrin Schps Rosemary Setchfield Marko Nieminen 《Oikos》2002,98(1):87-97
This study examines the causes of emigration from small fragments of suitable habitat in a species that has a distinct metapopulation structure, frequent turnover of local populations, and substantial migration among local populations and currently unoccupied habitat fragments. We conducted a field experiment in which 727 individuals of the Glanville fritillary butterfly ( Melitaea cinxia ) originating from four regions were marked and released simultaneously in a natural environment. In three of the four source regions, larvae for the experiment were collected from dozens of small local populations, some of which had been established in the previous summer (new populations), whereas the remaining populations were older. In two of the source regions, female butterflies prefer a host plant ( Veronica spicata ) that is not present in the release area, where there is only Plantago lanceolata , the preferred host plant of females from the other two source regions. We found that migration rate of males was unrelated to any of the factors studied in this experiment. In contrast, two factors influenced the migration rate of females. First, Veronica -preferring females had higher emigration rate than Plantago- preferring females from the Plantago -containing release patches, demonstrating that the individual perception of habitat quality significantly influences the migration rate of females. Second, females from newly-established populations were more dispersive than females from older populations, supporting the notion that metapopulation processes (recurrent colonizations) select for increased migration. The observed migration rate was not correlated with any body size measurements, and thus the observed differences in migration rate were apparently caused by differences in the behaviour of female butterflies rather than in their flight capacity. 相似文献
999.
Guenter Stoesser Wendy Baker Alexandra van den Broek Evelyn Camon Maria Garcia-Pastor Carola Kanz Tamara Kulikova Rasko Leinonen Quan Lin Vincent Lombard Rodrigo Lopez Nicole Redaschi Peter Stoehr Mary Ann Tuli Katerina Tzouvara Robert Vaughan 《Nucleic acids research》2002,30(1):21-26
The EMBL Nucleotide Sequence Database (aka EMBL-Bank; http://www.ebi.ac.uk/embl/) incorporates, organises and distributes nucleotide sequences from all available public sources. EMBL-Bank is located and maintained at the European Bioinformatics Institute (EBI) near Cambridge, UK. In an international collaboration with DDBJ (Japan) and GenBank (USA), data are exchanged amongst the collaborating databases on a daily basis. Major contributors to the EMBL database are individual scientists and genome project groups. Webin is the preferred web-based submission system for individual submitters, whilst automatic procedures allow incorporation of sequence data from large-scale genome sequencing centres and from the European Patent Office (EPO). Database releases are produced quarterly. Network services allow free access to the most up-to-date data collection via FTP, email and World Wide Web interfaces. EBI’s Sequence Retrieval System (SRS), a network browser for databanks in molecular biology, integrates and links the main nucleotide and protein databases plus many other specialized databases. For sequence similarity searching, a variety of tools (e.g. Blitz, Fasta, BLAST) are available which allow external users to compare their own sequences against the latest data in the EMBL Nucleotide Sequence Database and SWISS-PROT. All resources can be accessed via the EBI home page at http://www.ebi.ac.uk. 相似文献
1000.
Motomi Genkai-Kato Tatsuki Sekino Takehito Yoshida Hitoshi Miyasaka Tamara V. Khodzher Olga A. Belykh Natalia G. Melnik Zen’ichiro Kawabata Masahiko Higashi Masami Nakanishi 《Ecological Research》2002,17(2):135-142
To diagnose the nutritional status of phytoplankton in Lake Baikal, surveys for
the determination of concentrations of particulate carbon (PC), nitrogen (PN) and phosphorus (PP) and their ratios were conducted at six stations in March, June, August and October 1999. The concentrations of PC and PN were lower than, and those of PP were similar to, those in another mesotrophic lake except at the station near the mouth of the largest input river, Selenga River, of Lake Baikal. The PC : PN : PP ratio was 102 : 13 : 1, considerably close to the Redfield ratio. The ratio was constant against spatiotemporal changes. These indicate that phytoplankton in Lake Baikal were exposed to no deficiency in nitrogen nor phosphorus. From a viewpoint of the nutritional status of phytoplankton, Lake Baikal might be viewed as an ocean rather than as a lake. 相似文献