64 research outputs found

    Stimulation of Capacitative Calcium Entry in HL-60 Cells By Nanosecond Pulsed Electric Fields

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    Nanosecond pulsed electric fields (nsPEFs) are hypothesized to affect intracellular structures in living cells providing a new means to modulate cell signal transduction mechanisms. The effects of nsPEFs on the release of internal calcium and activation of calcium influx in HL-60 cells were investigated by using real time fluorescent microscopy with Fluo-3 and fluorometry with Fura-2. nsPEFs induced an increase in intracellular calcium levels that was seen in all cells. With pulses of 60 ns duration and electric fields between 4 and 15 kV/cm, intracellular calcium increased 200-700 nM, respectively, above basal levels (similar to100 nM), while the uptake of propidium iodide was absent. This suggests that increases in intracellular calcium were not because of plasma membrane electroporation. nsPEF and the purinergic agonist UTP induced calcium mobilization in the presence and absence of extracellular calcium with similar kinetics and appeared to target the same inositol 1,4,5-trisphosphate- and thapsigargin-sensitive calcium pools in the endoplasmic reticulum. For cells exposed to either nsPEF or UTP in the absence of extracellular calcium, there was an electric field-dependent or UTP dose-dependent increase in capacitative calcium entry when calcium was added to the extracellular media. These findings suggest that nsPEFs, like ligand-mediated responses, release calcium from similar internal calcium pools and thus activate plasma membrane calcium influx channels or capacitative calcium entry

    Introduction to the Edward Elgar Research Handbook on Law and Emotion

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    The role of emotion in law has long been shrouded in mystery. The legal system is built on assumptions about human behavior, including assumptions about emotion. Thus, unavoidably, understanding emotion is an essential part of building a fairer, more effective system. Yet the emergence and growth of Law and Emotion as a field of study has been slowed by the belief that merely by acknowledging emotion, scholars and jurists would undermine the rule of law. It has been further hampered by the suspicion that emotions are too ephemeral or subjective to be understood in any systematic way. For too long, the result has been a strange, unproductive stasis: a legal system buffeted by emotional influences it refuses to investigate—or even to name

    Regulation of Intracellular Calcium Concentration by Nanosecond Pulsed Electric Fields

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    Changes in [Ca2+]i response of individual Jurkat cells to nanosecond pulsed electric fields (nsPEFs) of 60 ns and field strengths of 25, 50, and 100 kV/cm were investigated. The magnitude of the nsPEF-induced rise in [Ca2+]i was dependent on the electric field strength. With 25 and 50 kV/cm, the [Ca2+]i response was due to the release of Ca2+ from intracellular stores and occurred in less than 18 ms. With 100 kV/cm, the increase in [Ca2+]i was due to both internal release and to influx across the plasma membrane. Spontaneous changes in [Ca2+]i exhibited a more gradual increase over several seconds. The initial, pulse-induced [Ca2+]i response initiates at the poles of the cell with respect to electrode placement and co-localizes with the endoplasmic reticulum. The results suggest that nsPEFs target both the plasma membrane and subcellular membranes and that one of the mechanisms for Ca2+ release may be due to nanopore formation in the endoplasmic reticulum

    LDSD POST2 Simulation and SFDT-1 Pre-Flight Launch Operations Analyses

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    The Low-Density Supersonic Decelerator (LDSD) Project's first Supersonic Flight Dynamics Test (SFDT-1) occurred June 28, 2014. Program to Optimize Simulated Trajectories II (POST2) was utilized to develop trajectory simulations characterizing all SFDT-1 flight phases from drop to splashdown. These POST2 simulations were used to validate the targeting parameters developed for SFDT- 1, predict performance and understand the sensitivity of the vehicle and nominal mission designs, and to support flight test operations with trajectory performance and splashdown location predictions for vehicle recovery. This paper provides an overview of the POST2 simulations developed for LDSD and presents the POST2 simulation flight dynamics support during the SFDT-1 launch, operations, and recovery

    Increased circulating desmosine and age-dependent elastinolysis in idiopathic pulmonary fibrosis

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    Abstract Although chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) seem to be opposite entities from a clinical perspective, common initial pathogenic steps have been suggested in both lung diseases. Emphysema is caused by an elastase/anti-elastase imbalance leading to accelerated elastin degradation. Elastinolysis is however, also accelerated in the IPF patients’ lungs. The amino acids desmosine and isodesmosine (DES) are unique to elastin. During the degradation process, elastases liberate DES from elastin fibers. Blood DES levels consequently reflect the rate of systemic elastinolysis and are increased in COPD. This is the first report describing elevated DES levels in IPF patients. We also demonstrated that the age-related increment of DES concentrations is enhanced in IPF. Our current study suggests that elastinolysis is a shared pathogenic step in both COPD and IPF. Further investigation is required to establish the relevance of accelerated elastin degradation in IPF and to determine whether decelerating this process leads to slower progression of lung fibrosis and better survival for patients with IPF.https://deepblue.lib.umich.edu/bitstream/2027.42/142803/1/12931_2018_Article_747.pd

    Bioelectric Effects of Intense Nanosecond Pulses

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    Electrical models for biological cells predict that reducing the duration of applied electrical pulses to values below the charging time of the outer cell membrane (which is on the order of 100 ns for mammalian cells) causes a strong increase in the probability of electric field interactions with intracellular structures due to displacement currents. For electric field amplitudes exceeding MV/m, such pulses are also expected to allow access to the cell interior through conduction currents flowing through the permeabilized plasma membrane. In both cases, limiting the duration of the electrical pulses to nanoseconds ensures only nonthermal interactions of the electric field with subcellular structures. This intracellular access allows the manipulation of cell functions. Experimental studies, in which human cells were exposed to pulsed electric fields of up to 300 kY/cm amplitude with durations as short as 3 ns, have confirmed this hypothesis and have shown that it is possible to selectively alter the behavior and/or survival of cells. Observed nanosecond pulsed effects at moderate electric fields include intracellular release of calcium and enhanced gene expression, which could have long term implications on cell behavior and function. At increased electric fields, the application of nanosecond pulses induces a type of programmed cell death, apoptosis, in biological cells. Cell survival studies with 10 ns pulses have shown that the viability of the cells scales inversely with the electrical energy density, which is similar to the ‘dose’ effect caused by ionizing radiation. On the other hand, there is experimental evidence that, for pulses of varying durations, the onset of a range of observed biological effects is determined by the electrical charge that is transferred to the cell membrane during pulsing. This leads to an empirical similarity law for nanosecond pulse effects, with the product of electric field intensity, pulse duration, and the square root of the number of pulses as the similarity parameter. The similarity law allows one not only to predict cell viability based on pulse parameters, but has also been shown to be applicable for inducing platelet aggregation, an effect which is triggered by internal calcium release. Applications for nanosecond pulse effects cover a wide range: from a rather simple use as preventing biofouling in cooling water systems, to advanced medical applications, such as gene therapy and tumor treatment. Results of this continuing research are leading to the development of wound healing and skin cancer treatments, which are discussed in some detail

    Impact of issuing longer- versus shorter-duration prescriptions: a systematic review.

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    BACKGROUND: Long-term conditions place a substantial burden on primary care services, with drug therapy being a core aspect of clinical management. However, the ideal frequency for issuing repeat prescriptions for these medications is unknown. AIM: To examine the impact of longer-duration (2-4 months) versus shorter-duration (28-day) prescriptions. DESIGN AND SETTING: Systematic review of primary care studies. METHOD: Scientific and grey literature databases were searched from inception until 21 October 2015. Eligible studies were randomised controlled trials and observational studies that examined longer prescriptions (2-4 months) compared with shorter prescriptions (28 days) in patients with stable, chronic conditions being treated in primary care. Outcomes of interest were: health outcomes, adverse events, medication adherence, medication wastage, professional administration time, pharmacists' time and/or costs, patient experience, and patient out-of-pocket costs. RESULTS: From a search total of 24 876 records across all databases, 13 studies were eligible for review. Evidence of moderate quality from nine studies suggested that longer prescriptions are associated with increased medication adherence. Evidence from six studies suggested that longer prescriptions may increase medication waste, but results were not always statistically significant and were of very low quality. No eligible studies were identified that measured any of the other outcomes of interest, including health outcomes and adverse events. CONCLUSION: There is insufficient evidence relating to the overall impact of differing prescription lengths on clinical and health service outcomes, although studies do suggest medication adherence may improve with longer prescriptions. UK recommendations to provide shorter prescriptions are not substantiated by the current evidence base

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
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