425 research outputs found
Microfluidic device for drug delivery
A microfluidic device is provided for delivering a drug to an individual. The microfluidic device includes a body that defines a reservoir for receiving the drug therein. A valve interconnects the reservoir to an output needle that is insertable into the skin of an individual. A pressure source urges the drug from the reservoir toward the needle. The valve is movable between a closed position preventing the flow of the drug from the reservoir to the output needle and an open position allowing for the flow of the drug from the reservoir to the output needle in response to a predetermined condition in the physiological fluids of the individual
Identification and expression of Hop, an atypical homeobox gene expressed late in lens fiber cell terminal differentiation
Micro-Fluidic Device for Drug Delivery
A microfluidic device is provided for delivering a drug to an individual. The microfluidic device includes a body that defines a reservoir for receiving the drug therein. A valve interconnects the reservoir to an output needle that is insertable into the skin of an individual. A pressure source urges the drug from the reservoir toward the needle. The valve is movable between a closed position preventing the flow of the drug from the reservoir to the output needle and an open position allowing for the flow of the drug from the reservoir to the output needle in response to a predetermined condition in the physiological fluids of the individual
A bi-polymer micro one-way valve
Abstract We have developed an in-plane bi-polymer check-valve for controlling microfluidic flow and preventing contamination between solutions by utilizing the elastic force of a swollen hydrogel. The valve was created using microfluidic tectonics, a fabrication procedure that allows construction of microscale components and autonomous systems using liquid-phase photopolymerization and in situ fabrication. The valve is composed of rigid parts (poly isobornyl acrylate) that provide a base frame, and compliant parts (hydrogel) that seal off the channel. The rigid part was fabricated by filling a polycarbonate cartridge with the isobornyl acrylate based prepolymer followed by UV light exposure through a photomask forming a chamber. To obtain well-defined chamber walls, a double exposing method (first exposure under lower UV dosage, then second exposure after filling the formed channel with DI water) was applied. Next, the chamber was filled with the hydrogel prepolymer mixture and exposed to UV light through a valve mask to define the compliant component of the device, resulting in an in-plane bi-polymer structure. The valve is actively assembled in situ providing precise sealing using low resolution lithography fabrication methods. Valve performance can be adjusted by varying the device geometry. Due to its in-plane structure and in situ fabrication process, microfluidic devices incorporating microvalves can be designed and fabricated conveniently
3,4-Methylenedioxymethamphetamine Activates Nuclear Factor- κB, Increases Intracellular Calcium, and Modulates Gene Transcription in Rat Heart Cells
3,4-Methylenedioxymethamphetamine (MDMA) is an illicit psychoactive drug that has gained immense popularity among teenagers and young adults. The cardiovascular toxicological consequences of abusing this compound have not been fully characterized. The present study utilized a transient transfection/dual luciferase genetic reporter assay, fluorescence confocal microscopy, and gene expression macroarray technology to determine nuclear factor-κB (NF-κB) activity, intracellular calcium balance, mitochondrial depolarization, and gene transcription profiles, respectively, in cultured rat striated cardiac myocytes (H9c2) exposed to MDMA. At concentrations of 1×10−3 M and 1×10−2 M, MDMA significantly enhanced NF-κB reporter activity compared with 0 M (medium only) control. This response was mitigated by cotransfection with IκB for 1×10−3 M but not 1×10−2 M MDMA. MDMA significantly increased intracellular calcium at concentrations of 1×10−3 M and 1×10−2 M and caused mitochondrial depolarization at 1×10−2 M. MDMA increased the transcription of genes that are considered to be biomarkers in cardiovascular disease and genes that respond to toxic indults. Selected gene activation was verified via temperature-gradient RT-PCR conducted with annealing temperatures ranging from 50°C to 65°C. Collectively, these results suggest that MDMA may be toxic to the heart through its ability to activate the myocardial NF-κB response, disrupt cytosolic calcium and mitochondrial homeostasis, and alter gene transcription
Enhanced immunoprecipitation techniques for the identification of RNA-binding protein partners: IGF2BP1 interactions in mammary epithelial cells
RNA-binding proteins (RBPs) regulate the expression of large cohorts of RNA species to produce programmatic changes in cellular phenotypes. To describe the function of RBPs within a cell, it is key to identify their mRNA-binding partners. This is often done by crosslinking nucleic acids to RBPs, followed by chemical release of the nucleic acid fragments for analysis. However, this methodology is lengthy, which involves complex processing with attendant sample losses, thus large amounts of starting materials and prone to artifacts. To evaluate potential alternative technologies, we tested exclusion-based purification of immunoprecipitates (IFAST or SLIDE) and report here that these methods can efficiently, rapidly, and specifically isolate RBP-RNA complexes. The analysis requires less than 1% of the starting material required for techniques that include crosslinking. Depending on the antibody used, 50% to 100% starting protein can be retrieved, facilitating the assay of endogenous levels of RBPs; the isolated ribonucleoproteins are subsequently analyzed using standard techniques, to provide a comprehensive portrait of RBP complexes. Using exclusion-based techniques, we show that the mRNA-binding partners for RBP IGF2BP1 in cultured mammary epithelial cells are enriched in mRNAs important for detoxifying superoxides (specifically glutathione peroxidase [GPX]-1 and GPX-2) and mRNAs encoding mitochondrial proteins. We show that these interactions are functionally significant, as loss of function of IGF2BP1 leads to destabilization of GPX mRNAs and reduces mitochondrial membrane potential and oxygen consumption. We speculate that this underlies a consistent requirement for IGF2BP1 for the expression of clonogenic activity in vitro
Cell-free translation and purification of Arabidopsis thaliana regulator of G signaling 1 protein
Arabidopsis thaliana Regulator of G protein Signalling 1 (AtRGS1) is a protein with a predicted N-terminal 7-transmembrane (7TM) domain and a C-terminal cytosolic RGS1 box domain. The RGS1 box domain exerts GTPase activation (GAP) activity on Gα (AtGPA1), a component of heterotrimeric G protein signaling in plants. AtRGS1 may perceive an exogenous agonist to regulate the steady-state levels of the active form of AtGPA1. It is uncertain if the full length RGS1 protein exerts any atypical effects on Gα, nor has it been established exactly how AtRGS1 contributes to perception of an extracellular signal and transmits this response to a G-protein dependent signaling cascade. Such an understanding can be deduced from in vitro studies using the purified and soluble RGS1-box domain. Further studies on full-length AtRGS1 have been inhibited due to the extreme low abundance of the endogenous AtRGS1 protein in plants and lack of a suitable heterologous system to express AtRGS1. Here, we describe methods to produce full-length AtRGS1 by cell free synthesis into unilamellar liposomes and nanodiscs. The cell-free synthesized AtRGS1 exhibits GTPase activating activity on Gα and can be purified to a level suitable for biochemical analyses
The ethos of physical activity delivery in mental health: a narrative study of service user experiences.
Our research into the physical activity experiences of people with severe mental illness has led us to take seriously the social and cultural environment in which physical activity is delivered. In this study, through narrative methodology, we examine service user accounts of physical activity to illuminate the characteristics of physical activity groups that are experienced as positive, helpful, or beneficial. We present several qualities and show how effective leadership and coaching is central to these qualities being present. We conclude that it is not so much what activity is delivered, but how it is delivered that is critical for sustained participation and positive outcomes
Social support for and through exercise and sport in a sample of men with serious mental illness.
Social support is important for people experiencing serious mental illness and is also important during the initiation and maintenance of exercise. In this article we draw on interpretive research into the experiences of 11 men with serious mental illness to explore four dimensions of social support both for and through exercise. Our findings suggest that informational, tangible, esteem, and emotional support were both provided for and given by participants through exercise. We conclude that experiences of both receiving and giving diverse forms of support in this way are significant for some people living with and recovering from serious mental illness
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