Search results for "ACTIVATION"
showing 10 items of 2079 documents
Induction capacity and influence of dThdMP on thymidine kinase activity of type 1 and 2 strains of herpes simplex virus
1978
The thymidine kinase inducing ability of 104 strains of herpes simplex virus was studied comparatively. A pronounced relationship was established between induction of the enzyme and the serotype of the strains. As a rule, the strains of serotype 2 are weaker inducer of dThd- and dCyd-kinase activity than serotype 1 strains. A certain parallelism exists between induction of both enzymes, however the activity of the thymidine kinase increases after infection with herpes simplex virus 4--5 times more than that of the dCyd-kinase. Adaptation of the strains to cell cultures only slightly modifies the inducing ability of the herpes simplex virus strains. The thymidine kinase activity induced by H…
Flavonoids against the SARS-CoV-2 induced inflammatory storm
2021
The disease severity of COVID-19, especially in the elderly and patients with co-morbidities, is characterized by hypercytokinemia, an exaggerated immune response associated with an uncontrolled and excessive release of proinflammatory cytokine mediators (cytokine storm). Flavonoids, important secondary metabolites of plants, have long been studied as therapeutic interventions in inflammatory diseases due to their cytokine-modulatory effects. In this review, we discuss the potential role of flavonoids in the modulation of signaling pathways that are crucial for COVID-19 disease, particularly those related to inflammation and immunity. The immunomodulatory ability of flavonoids, carried out …
Josephson-junction-based axion detection through resonant activation
2022
We discuss the resonant activation phenomenon on a Josephson junction due to the coupling of the Josephson system with axions. We show how such an effect can be exploited for axion detection. A nonmonotonic behavior, with a minimum, of the mean switching time from the superconducting to the resistive state versus the ratio of the axion energy and the Josephson plasma energy is found. We demonstrate how variations in switching times make it possible to detect the presence of the axion field. An experimental protocol for observing axions through their coupling with a Josephson system is proposed.
Role of the colored noise in a FitzHugh-Nagumo system driven by a periodic signal
2007
During these last years the interest in neuronal dynamics increased. The study of this kind of system has been carried out by using the FitzHugh-Nagumo (FHN) model that is a simplified modification of the Hodgkin-Huxley model. Many interesting phenomena can be observed in the presence of fluctuations: modification of detection threshold by manipulation of noisy parameters (FHN model), noise-induced activation and coeherence resonance for suitable noise amplitude (absence of periodic signal), resonant activation for high periodic signals and noise reduction, intrinsic stochastic resonance (ISR) in Hodgkin-Huxley neuron and the enhancement of a weak signal by tuning the subthreshold intrinsic…
EXTENDED VALIDATION OF DYNAMIC IRREVERSIBLE THERMOPORATION: A NOVEL THERMAL PROCESS FOR MICROBIAL INACTIVATION
2017
A novel thermal treatment for microorganism inactivation, characterized by a very rapid temperature increase (up to 30C/s) and a low final temperature (up to 65C) maintained for a relatively short holding time, has been recently presented and tested by the authors, showing microbial load reduction greater than 5 log units against several common bacteria and yeasts. With the aim of extending the possible use of the new thermal treatment to a wider microorganisms class, in this work the dynamic irreversible thermoporation (DIT) treatment was further tested on a well-known thermoresistant strain, the Enterococcus hirae: The results of these new experimental tests confirmed the reliability of t…
Neutron and gamma-ray radiation fields characterisation in an 241Am-Be irradiator in view of its use as reserach tool
2019
Introduction A neutron irradiation facility based on four 241Am–Be sources, activity of 1.11·1011 Bq each (yield ~7.0 ·106 n s-1), consisting in four source-channels and an irradiation channel placed in a tank filled with light water both as moderator and biological shielding, was realized at DEIM Department. The aim of this work is to evaluate neutron and gamma fluxes in several points inside the irradiation channel, in view of its use as a testing tool in various research activities. For this goal, an experimental measurement campaign was started also to validate Monte Carlo (MCNP5 code) simulation results. Methods Experimental measurements of neutron radiation fields (fast and thermal) w…
Photocatalytic inactivation of Legionella Pneumophila and aerobic bacteria consortium in water over TiO2/SiO2 fibres in a continuous reactor
2005
A continuous photoreactor, working in a total recycle mode and irradiated by a low-pressure Hg lamp, has been used to study the bactericidal effect of a photocatalyst, formed by TiO2 embedded in SiO2 fibres, on Legionella pneumophila and a consortium of common gram-negative aerobic bacteria: (Escherichia coli, Klebsiella sp., Pseudomona sp. and Proteus sp.) in water. The kinetic modeling of the inactivation process, carried out with the measured values of viable bacteria concentration at the outlet of photoreactor, evidenced that for each pass inside the photoreactor the ratio between the outlet and inlet cell concentrations was of order of 0.01 for the inactivation of L. pneumophila. For t…
A High-Throughput Mechanical Activator for Cartilage Engineering Enables Rapid Screening of in vitro Response of Tissue Models to Physiological and S…
2021
Articular cartilage is crucially influenced by loading during development, health, and disease. However, our knowledge of the mechanical conditions that promote engineered cartilage maturation or tissue repair is still incomplete. Current in vitro models that allow precise control of the local mechanical environment have been dramatically limited by very low throughput, usually just a few specimens per experiment. To overcome this constraint, we have developed a new device for the high throughput compressive loading of tissue constructs: the High Throughput Mechanical Activator for Cartilage Engineering (HiT-MACE), which allows the mechanoactivation of 6 times more samples than current tech…
Searching for wheat plants with low toxicity in celiac disease: Between direct toxicity and immunologic activation.
2009
Abstract Background Natural or induced variations in the noxiousness of gluten proteins for celiac disease (CD) patients are currently being investigated for their potential in breeding wheat crops with reduced toxicity. Aims We evaluated the bread wheat line C173 for its effects on the in vitro -grown duodenal mucosa of CD patients. Methods In vitro -grown duodenal mucosa biopsies of 19 CD patients on a gluten-free diet were exposed to peptic/tryptic-digested prolamins from bread wheat line C173 lacking gliadin–glutenin subunits, analyzed for morphology, cytokine and anti-tTG antibody production, and compared with mucosa biopsies exposed to prolamins from wild-type cv. San Pastore. Results…