Search results for " fragmentation"
showing 10 items of 421 documents
The HMG-CoA reductase inhibitor lovastatin protects cells from the antineoplastic drugs doxorubicin and etoposide
2002
Ras-homologous GTPases are involved in the regulation of genotoxic stress-induced gene expression and cell death. Since they need C-terminal isoprenylation for correct intracellular localization and function, we investigated whether depletion of cells from isopren precursor moieties using the HMG-CoA reductase inhibitor lovastatin affects cellular sensitivity to DNA damaging drugs. Here we show that lovastatin renders cells highly resistant to the tumor-therapeutic compound doxorubicin. Desensitization by lovastatin was reverted by co-treatment with GGPP indicating that inhibition of protein geranylgeranylation is involved in acquired doxorubicin resistance. Lovastatin does not influence ce…
A Taxonomy for App-Enabled Devices: Mastering the Mobile Device Jungle
2018
While the term application is known for a long time, what we now refer to as mobile apps has facilitated task-oriented, interoperable software. The term was initially only used for smartphones and tablets, but desktop software now is also referred to as apps. More important than the wording, however, is the trend towards app-enablement of many further kinds of devices such as smart TVs and wearables. App-enabled devices usually share some characteristics and developing apps is often similar. However, many complexities must be mastered: Device fragmentation and cross-platform app development already are challenging when only considering smartphones. When trying to grasp the field as a whole,…
Evaluation Framework of Hypertext Access for Program Comprehension Support
2008
Hypertext consists of text fragments connected by links enabling fast nonlinear browsing of the fragments. In case of program text there are many alternative ways to form the fragmentation and linkage. Transient hypertext is a general and well-grounded approach for offering capabilities to form versatile information access support for many kinds of central software maintenance activities. Transient hypertextual access structures (THASs) are data structures formed automatically based on situation dependent information needs of the users of program comprehension support tools. The approach has been implemented in HyperSoft system. It is aimed at supporting legacy software maintenance and comp…
Conservation genetics of an endemic from the Mediterranean Basin: high genetic differentiation but no genetic diversity loss from the last population…
2013
The Mediterranean Basin is a biodiversity hotspot, housing > 11.000 narrowly endemic plant species, many of which are declining due to mass tourism and agricultural intensification. To investigate the genetic resource impacts of ongoing habitat loss and degradation, we characterized the genetic variation in the last known populations of Leopoldia gussonei, a self-compatible endangered Sicilian Grape Hyacinth numbering less than 3,000 remaining individuals, using AFLP. Results demonstrated significant genome-wide genetic differentiation among all extant populations (I broken vertical bar(ST) = 0.05-0.56), and genetic clustering according to geographic location. Gene diversity was fairly c…
STR analysis of artificially degraded DNA--results of a collaborative European exercise.
2003
Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak heig…
Effects of environment and genotype on dispersal differ across departure, transfer and settlement in a butterfly metapopulation
2022
Active dispersal is driven by extrinsic and intrinsic factors at the three stages of departure, transfer and settlement. Most empirical studies capture only one stage of this complex process, and knowledge of how much can be generalized from one stage to another remains unknown. Here we use genetic assignment tests to reconstruct dispersal across 5 years and 232 habitat patches of a Glanville fritillary butterfly ( Melitaea cinxia ) metapopulation. We link individual dispersal events to weather, landscape structure, size and quality of habitat patches, and individual genotype to identify the factors that influence the three stages of dispersal and post-settlement survival. We found that ne…
Risk factors for Lyme disease : A scale-dependent effect of host species diversity and a consistent negative effect of host phylogenetic diversity
2021
Biodiversity can influence disease risk. One example of a diversity-disease relationship is the dilution effect, which suggests higher host species diversity (often indexed by species richness) reduces disease risk. While numerous studies support the dilution effect, its generality remains controversial. Most studies of diversity-disease relationships have overlooked the potential importance of phylogenetic diversity. Furthermore, most studies have tested diversity-disease relationships at one spatial scale, even though such relationships are likely scale dependent. Using Lyme disease as a model system, we investigated the effects of host species richness and phylogenetic relatedness on the…
Dryofragin, a phloroglucinol derivative, induces apoptosis in human breast cancer MCF-7 cells through ROS-mediated mitochondrial pathway
2012
Dryofragin is a phloroglucinol derivative extracted from Dryopteris fragrans (L.) Schott. In this study, the anticancer activity of dryofragin on human breast cancer MCF-7 cells was investigated. Dryofragin inhibited the growth of MCF-7 cells in a time and concentration-dependent manner. The cell viability was measured using MTT assay. After treatment with dryofragin for 72, 48 and 24 h, the IC₅₀ values were 27.26, 37.51 and 76.10 μM, respectively. Further analyses of DNA fragmentation and Annexin V-PI double-labeling indicated an induction of apoptosis. Dryofragin-treatment MCF-7 cells had a significantly accumulation of reactive oxygen species (ROS), as well as an increased percentage of …
The fall and the fragmentation of national clusters: Cluster evolution in the paper and pulp industry
2012
Abstract A common expectation in evolutionary cluster studies is that national clusters engage in competitive interactions that lead to a continuous stream of changes in global dominance. Our fuzzy-set analysis on the evolution of the paper and pulp industry demonstrates that globalization has dramatically changed this situation. National clusters have largely faded away; the value chain dominance is now held by technology suppliers who are global hubs in majority of identifiable business activities in the focal industry. Our results imply that when industrial decline is accentuated by industrial concentration in some part of the value chain the national clusters may lose their importance.
Detection of primary DNA damage in Chlamydomonas reinhardtii by means of modified microgel electrophoresis.
1997
The assessment of genotoxic potential in surface water requires test methods, among which are those that detect initial DNA damage in organisms of aquatic biocenosis. The microgel electrophoresis (MGE) "comet assay" was applied to a ubiquitous unicellular green alga (Chlamydomonas reinhardtii) to detect DNA damage caused by genotoxins. For this, the test protocol described by Singh NP et al. [Exp Cell Res 175: 184-191, 1988] was modified. Major modifications were the use of alkaline lysis buffer with ionic detergents and the reduction of preincubation and electrophoresis times. Short-time exposure of Chlamydomonas to the well-known genotoxicants 4-nitroquinoline-1-oxide (4-NQO), N-nitrosodi…