127 research outputs found
The Use of a Stringent Selection System Allows the Identification of DNA Elements that Augment Gene Expression
The use of high stringency selection systems often results in the induction of very few recombinant mammalian cell lines, which limits the ability to isolate a cell line with favorable characteristics. The employment of for instance STAR elements in DNA constructs elevates the induced number of colonies and also the protein expression levels in these colonies. Here, we describe a method to systematically identify genomic DNA elements that are able to induce many stably transfected mammalian cell lines. We isolated genomic DNA fragments upstream from the human Rb1 and p73 gene loci and cloned them around an expression cassette that contains a very stringent selection marker. Due to the stringency of the selection marker, hardly any colony survives without flanking DNA elements. We tested fourteen ~3500Â bp DNA stretches from the Rb1 and p73 loci. Only two ~3500Â bp long DNA fragments, called Rb1E and Rb1F, induced many colonies in the context of the stringent selection system and these colonies displayed high protein expression levels. Functional analysis showed that the Rb1 DNA fragments contained no enhancer, promoter, or STAR activity. Our data show the potential of a methodology to identify novel gene expression augmenting DNA elements in an unbiased manner
Langstroth hive construction with cement-vermiculite
Exfoliated vermiculite is a light-weight and cheap product that, because of its thermal resistance, has become a valuable insulating material. With regard to its use in beekeeping, this research tested whether the box for honey bees constructed with cement-vermiculite mortar (CVM) presents physical characteristics similar to those of wood. The experiment was carried out at SeropĂŠdica, RJ, Brazil, for eight months. The cement-vermiculite mortar was compared with a control material (pinewood), in the construction of Langstroth boxes and boards, in a completely randomized design, with respect to thermal control, thermal conductivity and its capacity to absorb and lose water. The production cost for a CVM box was estimated. There were no internal temperature differences between CVM and wooden boxes. Thermal conductivity values for CVM and pinewood were similar. CVM absorbed more water and lost water faster than pinewood. Since CVM boxes can be easily constructed, at a low cost and with similar characteristics as traditional boxes, made of wood, the material can be recommended for use in non-migratory beekeeping
The Cyclic AMP Cascade Is Altered in the Fragile X Nervous System
Fragile X syndrome (FX), the most common heritable cause of mental retardation and autism, is a developmental disorder characterized by physical, cognitive, and behavioral deficits. FX results from a trinucleotide expansion mutation in the fmr1 gene that reduces levels of fragile X mental retardation protein (FMRP). Although research efforts have focused on FMRP's impact on mGluR signaling, how the loss of FMRP leads to the individual symptoms of FX is not known. Previous studies on human FX blood cells revealed alterations in the cyclic adenosine 3â˛, 5â˛-monophosphate (cAMP) cascade. We tested the hypothesis that cAMP signaling is altered in the FX nervous system using three different model systems. Induced levels of cAMP in platelets and in brains of fmr1 knockout mice are substantially reduced. Cyclic AMP induction is also significantly reduced in human FX neural cells. Furthermore, cAMP production is decreased in the heads of FX Drosophila and this defect can be rescued by reintroduction of the dfmr gene. Our results indicate that a robust defect in cAMP production in FX is conserved across species and suggest that cAMP metabolism may serve as a useful biomarker in the human disease population. Reduced cAMP induction has implications for the underlying causes of FX and autism spectrum disorders. Pharmacological agents known to modulate the cAMP cascade may be therapeutic in FX patients and can be tested in these models, thus supplementing current efforts centered on mGluR signaling
The anti-vaccination movement and resistance to allergen-immunotherapy: a guide for clinical allergists
Despite over a century of clinical use and a well-documented record of efficacy and safety, a growing minority in society questions the validity of vaccination and fear that this common public health intervention is the root-cause of severe health problems. This article questions whether growing public anti-vaccine sentiments might have the potential to spill-over into other therapies distinct from vaccination, namely allergen-immunotherapy. Allergen-immunotherapy shares certain medical vernacular with vaccination (e.g., allergy shots, allergy vaccines), and thus may become "guilty by association" due to these similarities. Indeed, this article demonstrates that anti-vaccine websites have begun unduly discrediting this allergy treatment regimen. Following an explanation of the anti-vaccine movement, the article aims to provide guidance on how clinicians can respond to patient fears towards allergen-immunotherapy in the clinical setting. This guide focuses on the provision of reliable information to patients in order to dispel misconceived associations between vaccination and allergen-immunotherapy, and the discussion of the risks and benefits of both therapies in order to assist patients in making autonomous decisions about their choice of allergy treatment
Indiana Traffic Signal Hi Resolution Data Logger Enumerations
This document defines the enumerations used to encode events that occur on a traffic signal controllers with high resolution data loggers. The time resolution is to the nearest 100 milliseconds.
Background information on the development of high resolution controller data in Indiana can be found at: Smaglik E.J., A. Sharma, D.M. Bullock, J.R. Sturdevant, and G. Duncan, âEvent-Based Data Collection for Generating Actuated Controller Performance Measures, Transportation Research Record, #2035, TRB, National Research Council, Washington, DC, pp.97-106, 2007.http://dx.doi.org/10.3141/2035-11
Recent applications of high resolution data to develop traffic signal performance measures in Indiana can be found at: Outcome-Oriented Performance Measures for Management of Signalized Arterial Capacity http://dx.doi.org/10.3141/2192-03 Track Clearance Performance Measures for Railroad-Preempted Intersections http://dx.doi.org/10.3141/2192-06 Reliability, Flexibility, and Environmental Impact of Alternative Objective Functions for Arterial Offset Optimization http://dx.doi.org/10.3141/2259-02 Visual Education Tools to Illustrate Coordinated System Operation http://dx.doi.org/10.3141/2259 -0
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