14 research outputs found
Optimizing hyaluronidase dose and plasmid DNA delivery greatly improves gene electrotransfer efficiency in rat skeletal muscle
AbstractTransfection of rat skeletal muscle in vivo is a widely used research model. However, gene electrotransfer protocols have been developed for mice and yield variable results in rats. We investigated whether changes in hyaluronidase pre-treatment and plasmid DNA delivery can improve transfection efficiency in rat skeletal muscle. We found that pre-treating the muscle with a hyaluronidase dose suitable for rats (0.56U/g b.w.) prior to plasmid DNA injection increased transfection efficiency by >200% whereas timing of the pre-treatment did not affect efficiency. Uniformly distributing plasmid DNA delivery across the muscle by increasing the number of plasmid DNA injections further enhanced transfection efficiency whereas increasing plasmid dose from 0.2 to 1.6”g/g b.w. or vehicle volume had no effect. The optimized protocol resulted in ~80% (CI95%: 79â84%) transfected muscle fibers with a homogenous distribution. We also show that transfection was stable over five weeks of regular exercise or inactivity. Our findings show that species-specific plasmid DNA delivery and hyaluronidase pre-treatment greatly improves transfection efficiency in rat skeletal muscle
Infall Regions and Scaling Relations of X-ray Selected Groups
We use the Fifth Data Release of the Sloan Digital Sky Survey to study
X-ray-selected galaxy groups and compare their properties to clusters. We
search for infall patterns around the groups and use these to measure group
mass profiles to large radii. In previous work, we analyzed infall patterns for
an X-ray-selected sample of 72 clusters from the ROSAT All-Sky Survey. Here, we
extend this approach to a sample of systems with smaller X-ray fluxes selected
from the 400 Square Degree serendipitous survey of clusters and groups in ROSAT
pointed observations. We identify 16 groups with SDSS DR5 spectroscopy, search
for infall patterns, and compute mass profiles out to 2-6 Mpc from the group
centers with the caustic technique. No other mass estimation methods are
currently available at such large radii for these low-mass groups, because the
virial estimate requires dynamical equilibrium and the gravitational lensing
signal is too weak. Despite the small masses of these groups, most display
recognizable infall patterns. We use caustic and virial mass estimates to
measure the scaling relations between different observables, extending these
relations to smaller fluxes and luminosities than many previous surveys. Close
inspection reveals that three of the groups are subclusters in the outskirts of
larger clusters. A fourth group is apparently undergoing a group-group merger.
These four merging groups represent the most extreme outliers in the scaling
relations. Excluding these groups, we find ,
consistent with previous determinations for both clusters and groups.
Understanding cluster and group scaling relations is crucial for measuring
cosmological parameters from clusters.Comment: published in AJ Feb 2010, significantly revised in response to
referee report, title edite
TRY plant trait database â enhanced coverage and open access
Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of traitâbased plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for âplant growth formâ. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and traitâenvironmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
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National Information Infrastructure: A Cross-Country Comparison
Recommended from our members
National Information Infrastructure: A Cross-Country Comparison
Growth-phase coupled regulation of initiation of chromosomal replication by reversible N-Δ-acetylation of DnaA in Escherichia coli
Do current national and international guidelines have specific recommendations for older adults with bipolar disorder?:A brief report
OBJECTIVE: Older adults with bipolar disorder (OABD) are a growing segment of patients with bipolar disorder (BD) for which specific guidelines are warranted. Although, OABD are frequently excluded from randomized controlled trials due to their age or somatic comorbidity, more treatment data from a variety of sources have become available in recent years. It is expected that at least some of this emerging information on OABD would be incorporated into treatment guidelines available to clinicians around the world. METHODS: The International Society of Bipolar Disorders OABD task force compiled and compared recommendations from current national and international guidelines that specifically address geriatric or older individuals with BD (from year 2005 onwards). RESULTS: There were 34 guidelines, representing six continents and 19 countries. The majority of guidelines had no separate section on OABD. General principles for treating OABD with medication are recommended to be similar to those for younger adults, with special caution for side effects due to somatic comorbidity and concomitant medications. Therapeutic lithium serum levels are suggested to be lower but recommendations are very general and mostly not informed by specific research evidence. CONCLUSIONS: There is a lack of emphasis of OABD-specific issues in existing guidelines. Given the substantial clinical heterogeneity in BD across the life span, along with the rapidly expanding population of older individuals worldwide, and limited mental health workforce with geriatric expertise, it is critical that additional effort and resources be devoted to studying treatment interventions specific to OABD and that treatment guidelines reflect research findings. Copyright © 2016 John Wiley & Sons, Ltd