Search results for " Stabilization"
showing 10 items of 84 documents
HSF1-controlled and age-associated chaperone capacity in neurons and muscle cells of C. elegans.
2010
Protein stability under changing conditions is of vital importance for the cell and under the control of a fine-tuned network of molecular chaperones. Aging and age-related neurodegenerative diseases are directly associated with enhanced protein instability. Employing C. elegans expressing GFP-tagged luciferase as a reporter for evaluation of protein stability we show that the chaperoning strategy of body wall muscle cells and neurons is significantly different and that both are differently affected by aging. Muscle cells of young worms are largely resistant to heat stress, which is directly mediated by the stress response controlled through Heat Shock Transcription Factor 1. During recover…
Stabilization of hsp70 mRNA on prolonged cell exposure to hypertonicity
2002
AbstractProlonged exposure of 3T3 cells to 0.5 osM hypertonic medium induced the accumulation of hsp70 mRNAs. This increase in mRNA levels required active protein synthesis. A weak and transient activation of heat shock factor 1 (HSF1) was noted, but it was temporally uncoupled to the accumulation of the hsp70 mRNAs. Nuclear run-on assay and transfection experiments showed that hsp70 gene transcription was not affected by hypertonicity. ActD chase experiments showed that during hypertonic treatment, degradation of hsp70 mRNAs was markedly reduced. This effect did not appear to be a general phenomenon since the increase in mRNA level of another gene induced by hypertonicity (ATA2 transporter…
Ag5 nanoclusters with dual catalytic antiradical activities
2022
Silver nanoclusters of five atoms (Ag5) display outstanding catalytic activities for the deactivation of radicals. Using 2,2-diphenyl-1‑picrylhydrazyl (DPPH) radical as a model system, we observed a fast radical reduction to DPPH anions using only [Ag5] 3 to 4 orders of magnitude less than [DPPH]. Moreover, nanoclusters remain stable at the end of the reaction, and can deactivate again DPPH radicals at the same rate, indicating that they act as anti-radical catalysts. The radical scavenger catalytic activity of Ag5 proceeds selectively through the oxidation of methanol (used to dissolve the radical) to formaldehyde, which is supported by DFT calculations. The obtained catalytic rate constan…
Outcomes of aortic valve repair according to valve morphology and surgical techniques
2012
OBJECTIVES: The aim of this study was to assess the impact of aortic valve morphology and different surgical aortic valve repair techni- ques on long-term clinical outcomes. METHODS: Between February 2003 and May 2010, 216 patients with aortic insufficiency underwent aortic valve repair in our institu- tion. Ages ranged between 26 and 82 years (mean 53 ± 15 years). Aortic valve dysfunctions, according to functional classification, were: type I in 55 patients (25.5%), type II in 126 (58.3%) and type III in 35 (16.2%). Sixty-six patients (27.7%) had a bicuspid valve. Aortic valve repair techniques included sub-commissural plasty in 138 patients, plication in 84, free-edge reinforcement in 80,…
Geoarchaeological study of the Phoenician cemetery of Tyre-Al Bass (Lebanon) and geomorphological evolution of a tombolo
2008
The geoarchaeological record of the Phoenician necropolis of Al Bass (Lebanon) provides information concerning the geomorphological evolution of a late Holocene tombolo. Physical and chemical analysis of sediments indicates that the cemetery (9th century B.C.) was located near a littoral lagoon, between the dunes of a cuspate spit pointing toward the island of Tyre. From the sea apex of this spit, the moles mentioned in historical chronicles were constructed. Once mainland and island were connected, at the northern coast (where the port of Sidon was located), a sediment trap was formed, which quickly filled with silt. Afterwards, an extensive field of sand dunes buried all the archaeologica…
Bitumen stabilized ballast: a potential solution for railway track-bed
2016
Railway ballast degradation under dynamic loads progressively leads to loss of mechanical performance and geometry of the track, so that maintenance interventions are frequently needed. In order to system- atically avoid this issue, recently solutions have been proposed to reinforce track-bed by using polyur- ethane and/or resins as well as asphalt layers among others. Nonetheless, their main limitations are related to the high initial cost and low productivity. To cope with these limitations, in this study, bitumen stabilized ballast (BSB) is proposed as a new solu- tion for ballast stabilization. This method aims at improving durability and reducing settlement by mod- ifying both stiffnes…
How far the substituent effects in disubstituted cyclohexa-1,3-diene derivatives differ from those in bicyclo[2.2.2]octane and benzene?
2018
Substituents effects in cyclic diene derivatives are studied using quantum chemical modeling and compared to the corresponding effects in aromatic (benzene) and fully saturated (bicyclo[2.2.2]octane) compounds. In particular, electronic properties of the fixed group Y in a series of 3- and 4-X-substituted cyclohexa-1,3-diene-Y derivatives (where Y = NO2, COOH, COO− OH, O−, NH2, and X = NMe2, NH2, OH, OMe, Me, H, F, Cl, CF3, CN, CHO, COMe, CONH2, COOH, NO2, NO) are examined using the B3LYP/6-311++G(d,p) method. For this purpose, quantum chemistry models of the substituent effect: cSAR (charge of the substituent active region) and SESE (substituent effect stabilization energy) as well as trad…
Specific and global regulation of mRNA stability during osmotic stress in Saccharomyces cerevisiae.
2009
Hyperosmotic stress yields reprogramming of gene expression in Saccharomyces cerevisiae cells. Most of this response is orchestrated by Hog1, a stress-activated, mitogen-activated protein kinase (MAPK) homologous to human p38. We investigated, on a genomic scale, the contribution of changes in transcription rates and mRNA stabilities to the modulation of mRNA amounts during the response to osmotic stress in wild-type and hog1 mutant cells. Mild osmotic shock induces a broad mRNA destabilization; however, osmo-mRNAs are up-regulated by increasing both transcription rates and mRNA half-lives. In contrast, mild or severe osmotic stress in hog1 mutants, or severe osmotic stress in wild-type cel…
DEALING WITH RISK IN AGRICULTURE: A CROP LEVEL ANALYSIS AND MANAGEMENT PROPOSAL FOR ITALIAN FARMS
2020
Risk management plays a critical role in agriculture, which is particularly exposed to multiple and heterogeneous risk factors. In addition to the traditional basic risks that generally characterize any business venture, agriculture faces external factors, generally difficult to control and with a strong impact on farm profitability. These are firstly environmental (pests and diseases) and climatic conditions that affect the quantity and quality of agricultural production, but also the structural constraints of the agricultural market, which is characterised by a high degree of supply rigidity, price volatility and inelasticity of demand. This leads to the need to implement risk management …
Multi-functional hybrid-carbon nanotubes for advanced Ultra-High Molecular Weight Polyethylene-based nanocomposites: a novel approach for stabilizati…
2015
Our results demonstrate that immobilizing stabilizing molecules on nanoparticles, and using the latter as multifunctional filler for nanocomposites, is a viable route towards to produce high-performance polymeric materials