Search results for "Ligo"
showing 10 items of 1427 documents
A new method for the mapping of 5' ends of RNAs.
2008
In this article, we describe a new procedure to map 5' ends of RNAs. The procedure consists in the use of specific RNase H digestion of a hybrid formed by the RNA and a complementary DNA oligonucleotide. Northern blot hybridization of the resulting RNA fragment allows an accurate measurement of its length. Although we generally use this procedure as a control of previously performed primer extension analyses, the absence of nonspecific bands, which often occur in primer extensions on RNA templates with extended secondary structures, suggests that our method may be preferable when these difficult templates are analyzed.
4p16.1-p15.31 duplication and 4p terminal deletion in a 3-years old Chinese girl: Array-CGH, genotype-phenotype and neurological characterization
2014
Abstract Background Microscopically chromosome rearrangements of the short arm of chromosome 4 include the two known clinical entities: partial trisomy 4p and deletions of the Wolf-Hirschhorn critical regions 1 and 2 (WHSCR-1 and WHSCR-2, respectively), which cause cranio-facial anomalies, congenital malformations and developmental delay/intellectual disability. Methods/results We report on clinical findings detected in a Chinese patient with a de novo 4p16.1-p15.32 duplication in association with a subtle 4p terminal deletion of 6 Mb in size. This unusual chromosome imbalance resulted in WHS classical phenotype, while clinical manifestations of 4p trisomy were practically absent. Conclusio…
DNA Fingerprinting for the Protection of Endangered Species
1991
The main application of DNA fingerprinting is based on identity and paternity testing in man [6, 7]. In the last years it has also been increasingly used for zoological problems [2–5, 8, 10, 12, 13]. In this study DNA fingerprinting was applied for “forensics” in the field of protection of endangered species.
Bioaccumulation of PAHs from creosote-contaminated sediment in a laboratory-exposed freshwater oligochaete, Lumbriculus variegatus
2002
The oligochaete, Lumbriculus variegatus, was used for a bioaccumulation assay in the creosote-contaminated sediment of Lake Jämsänvesi in a 28-day experiment. The PAH concentrations of the whole body tissue of worms, sediments and water samples were determinated by GC-MS. Chemical analyses showed that benzo(k)fluoranthene, anthracene and fluorene were the main PAH compounds present in the tissue of oligochaetes, just as in the sediment. The biota-sediment accumulation factors (BSAFs) of the individual PAHs varied from 1.2 to 5.7. It is concluded that oligochaetes have a marked ability to accumulate and retain PAHs from creosote-contaminated sediment.
Toxicity of silver nanoparticles to Lumbriculus variegatus is a function of dissolved silver and promoted by low sediment pH
2017
Toxicity of silver nanoparticles (AgNPs) to benthic organisms is a major concern. The use of AgNPs in industry and consumer products leads to increasing release of AgNPs into the aquatic environment-sediments being the major sink. Effects of sediment pH on the toxicity of AgNPs to benthic oligochaeta Lumbriculus variegatus were studied in a 23-d toxicity test. Artificially prepared sediments (pH 5 and 7) were spiked with varying concentrations of uncoated AgNP, polyvinylpyrrolidone (PVP)-coated AgNP, and silver nitrate (AgNO3 ) as dissolved Ag reference. Number of individuals and biomass change were used as endpoints for the toxicity. The toxic effects were related to the bioaccessible conc…
Toxicokinetics, toxicity and lethal body residues of two chlorophenols in the oligochaete worm, Lumbriculus variegatus, in different sediments
2003
Bioavailability, toxicokinetics and toxicity (LC(50)) of water- and sediment-associated 2,4,5-trichlorophenol (2,4,5-TCP) and pentachlorophenol (PCP) were measured in Lumbriculus variegatus Müller in a set of experiments. The critical body residue approach was applied by measuring also the lethal body residues (LBR(50)). Freshwater and three different sediments with various sediment organic carbon (SOC) concentrations were used as exposure media. SOC decreased the bioavailability of both chlorophenols, and the uptake rates decreased by 81% and 91% for 2,4,5-TCP and PCP, respectively, in the sediment with a SOC of 6.9% compared to those in sediment with a SOC of 0.5%. SOC appeared to be an i…
SIMILARITIES IN BIOACCUMULATION PATTERNS OF POLYCHLORINATED DIBENZO-p-DIOXINS AND FURANS AND POLYCHLORINATED DIPHENYL ETHERS IN LABORATORY-EXPOSED OL…
2003
Sediment and chironomid samples were collected from a river in the vicinity of and downstream from a closed chlorophenol production plant, and they were analyzed for polychlorinated dibenzo-p-dioxins and furans (PCDD/F) and polychlorinated diphenyl ethers (PCDE). Bioaccumulation of these compounds from the sediments by the oligochaeta, Lumbriculus variegatus, and semipermeable membrane devices (SPMDs) was studied in a 28-d bioaccumulation test. The sum concentrations of PCDD/Fs and PCDEs in sediments varied spatially, peaking at the site below the production plant, but the congener composition remained fairly constant throughout the river. The sum concentrations of chironomids, oligochaetes…
Toxicity Testing of Silver Nanoparticles in Artificial and Natural Sediments Using the Benthic Organism Lumbriculus variegatus
2016
The increased use of silver nanoparticles (AgNP) in industrial and consumer products worldwide has resulted in their release to aquatic environments. Previous studies have mainly focused on the effects of AgNP on pelagic species, whereas few studies have assessed the risks to benthic invertebrates despite the fact that the sediments act as a large potential sink for NPs. In this study, the toxicity of sediment-associated AgNP was evaluated using the standard sediment toxicity test for chemicals provided by the Organization of Economic Cooperation and Development. The freshwater benthic oligochaete worm Lumbriculus variegatus was exposed to sediment-associated AgNP in artificial and natural …
Neuronal Cell Nuclear Factor. A Nuclear Receptor Possibly Involved in the Control of Neurogenesis and Neuronal Differentiation
1997
We have cloned from a cDNA library of neuronal derivatives of retinoic-acid-induced embryonic carcinoma cells a nuclear receptor that may be involved in the control of late neurogenesis and early neuronal differentiation. The receptor which is practically identical in sequence with germ cell nuclear factor, has been designated neuronal cell nuclear factor (NCNF). NCNF is exclusively expressed in the neuronal derivatives of PCC7-Mz1 cells, with the expression beginning within hours of exposure to retinoic acid. In the developing mouse brain, NCNF is expressed in the marginal zones of the neuroepithelium which are known to contain young postmitotic neurons. NCNF binds to the DRO sequence ther…
The Paper Industry in Germany, 1800–2000
2012
Germany is the biggest paper exporter in the world, the biggest paper producer in Europe and the fourth biggest producer in the world. It is also the biggest market in Europe and a major export market for European pulp producers. However, only three German pulp and paper companies made it to the top 100 list of the industry in 2010 and none made it into the top 50 (PPI 2011). This article describes the development of the German industry from the beginning of the nineteenth century to the present in order to explain the factors contributing to this unusual state of affairs in a country which, during the second Industrial Revolution, created major players in the new global oligopolies in chem…