Search results for " shock"

Fronts propagating with signal dependent speed in limited diffusion and related Hamilton-Jacobi formulations

2021

We consider a class of limited diffusion equations and explore the formation of diffusion fronts as the result of a combination of diffusive and hyperbolic transport. We analyze a new class of Hamilton-Jacobi equations arising from the convective part of general Fokker-Planck equations ruled by a non-negative diffusion coefficient that depends on the unknown and on the gradient of the unknown. We explore the main features of the solution of the Hamilton-Jacobi equations that contain shocks and propose a suitable numerical scheme that approximates the solution in a consistent way with respect to the solution of the associated Fokker-Planck equation. We analyze three model problems covering d…

Defining Kawasaki disease and pediatric inflammatory multisystem syndrome-temporally associated to SARS-CoV-2 infection during SARS-CoV-2 epidemic in…

2021

Abstract Background There is mounting evidence on the existence of a Pediatric Inflammatory Multisystem Syndrome-temporally associated to SARS-CoV-2 infection (PIMS-TS), sharing similarities with Kawasaki Disease (KD). The main outcome of the study were to better characterize the clinical features and the treatment response of PIMS-TS and to explore its relationship with KD determining whether KD and PIMS are two distinct entities. Methods The Rheumatology Study Group of the Italian Pediatric Society launched a survey to enroll patients diagnosed with KD (Kawasaki Disease Group – KDG) or KD-like (Kawacovid Group - KCG) disease between February 1st 2020, and May 31st 2020. Demographic, clini…

Hsp60 Inhibitors and Modulators

2019

In this chapter, we focus on the 60 KDa Heat Shock Protein (Hsp60) and discuss some of its biological, molecular and pathological features. The structural and mechanistic aspect of the Hsp60 folding cycle will be also presented. We further illustrate how Hsp60 may be involved in many diseases and therefore considered as an effective therapeutic or theranostic target. Finally, the state-of-the-art on the development of Hsp60 and bacterial GroEL inhibitors and modulators of their expression will be illustrated. This is discussed in the light of a negative chaperonotherapy, and the consequent development of inhibitors, as well as positive chaperonotherapy, in the event its excessive activity i…

Essays on financial stability: an analysis based on NUTS2 and NUTS3 data for Italy

Cell inactivation and membrane damage after long-term treatments at sub-zero temperature in the supercooled and frozen states.

2008

The survival of cells subjected to cooling at sub-zero temperature is of paramount concern in cryobiology. The susceptibility of cells to cryopreservation processes, especially freeze-thawing, stimulated considerable interest in better understanding the mechanisms leading to cell injury and inactivation. In this study, we assessed the viability of cells subjected to cold stress, through long-term supercooling experiments, versus freeze-thawing stress. The viability of Escherichia coli, Saccharomyces cerevisiae, and leukemia cells were assessed over time. Supercooled conditions were maintained for 71 days at -10 degrees C, and for 4 h at -15 degrees C, and -20 degrees C, without additives or…

Vipp1: a very important protein in plastids?!

2011

As a key feature in oxygenic photosynthesis, thylakoid membranes play an essential role in the physiology of plants, algae, and cyanobacteria. Despite their importance in the process of oxygenic photosynthesis, their biogenesis has remained a mystery to the present day. A decade ago, vesicle-inducing protein in plastids 1 (Vipp1) was described to be involved in thylakoid membrane formation in chloroplasts and cyanobacteria. Most follow-up studies clearly linked Vipp1 to membranes and Vipp1 interactions as well as the defects observed after Vipp1 depletion in chloroplasts and cyanobacteria indicate that Vipp1 directly binds to membranes, locally stabilizes bilayer structures, and thereby ret…

Deciliation: A stressful event for Paracentrotus lividus embryos.

1998

In this report, by using mono- and two-dimensional electrophoretic analysis, we demonstrate that deciliation on sea urchin embryos induces a stress response. Deciliation indeed causes not only the activation of ciliary subroutine, but also a transient decrease of bulk protein synthesis. This decrease is in agreement with our previous results on heat shock response in sea urchin, although deciliation does not induce the expression of the same main hsp set. We were able to characterize one main deciliation-stress protein of 40 kDa whose expression is transiently induced by deciliation and whose localisation is likely to be nuclear.

(DIS)Assembly and Structural Stability of mtHsp60 and its Precursor NaÏve Form

2015

Heat shock protein 60kDa is a molecular chaperone (GroEL human homolog) that assists protein folding in mitochondria (mtHsp60). It is synthesized in the cell cytoplasm as a higher molecular weight precursor form (p-mtHsp60) containing a N-terminal targeting sequence, that is cleaved after import into the mitochondrial matrix [1, 2].It has been established, and demonstrated by various techniques, Hsp60 can accumulate in the cytosol, in various pathological conditions (i.e., cancer and chronic inflammatory diseases). The cytosolical Hsp60 accumulation mechanism may occur with or without mitochondrial release concomitantly, so that in the cytosol the two types of 60 kDa chaperonin proteins, (m…

Heat shock protein-antigen fusions lose their enhanced immunostimulatory capacity after endotoxin depletion.

2008

Heat shock proteins (HSPs) induce cross-presentation of antigens by dendritic cells (DC) as well as DC maturation. These properties make HSP antigen complexes good candidates to prime CD8 T cell responses against tumor-associated antigens. In this study, we analyzed four different members of the HSP70 family fused to a fragment of ovalbumin (OVA) as a model tumor antigen. E. coli-derived recombinant HSP70-OVA fusion proteins efficiently primed antigen-specific cytotoxic T cells in short-term in vivo immunization assays. Because of concerns that the adjuvant effect of HSPs may be due to endotoxin contamination, we studied this issue in detail. Induction of OVA-specific cytotoxicity was signi…

Correlation between the level of the potential biomarker, heat-shock protein, and the occurrence of DNA damage in the dab, Limanda limanda: a field s…

2000

In the present study, heat-shock protein of M-r 70 kDa (HSP70), a marker of cellular stress response, was validated as a potential biomarker under field conditions. The dab, Limanda limanda (female, size greater than or equal to 25 cm, spawning maturity stage 2) was used as the indicator organism. The data on HSP level were correlated with the occurrence of DNA damage, measured in the same specimens of L. limanda, to prove the usefulness of the method. The area under investigation was the North Sea. Four locations were selected: station N01, close to Heligoland, in the North Sea; station N04 at the Dogger Bank; station N06 at the Firth of Forth; and station G08 in the English Channel. Ten a…