Search results for "Defence mechanism"
showing 10 items of 34 documents
Analysis of the Molecular Dialogue Between Gray Mold (Botrytis cinerea) and Grapevine (Vitis vinifera) Reveals a Clear Shift in Defense Mechanisms Du…
2015
Mature grapevine berries at the harvesting stage (MB) are very susceptible to the gray mold fungus Botrytis cinerea, while veraison berries (VB) are not. We conducted simultaneous microscopic and transcriptomic analyses of the pathogen and the host to investigate the infection process developed by B. cinerea on MB versus VB, and the plant defense mechanisms deployed to stop the fungus spreading. On the pathogen side, our genome-wide transcriptomic data revealed that B. cinerea genes upregulated during infection of MB are enriched in functional categories related to necrotrophy, such as degradation of the plant cell wall, proteolysis, membrane transport, reactive oxygen species (ROS) genera…
Determination of pollutants with multixenobiotic -resistance inhibiting properties
1995
Abstract Recent evidence indicates that inherent presence of multixenobiotic resistance (MXR) mechanism represents a general biological defence mechanism for protection of organisms against both endogenous and environmental toxins. In aquatic organisms exposed to polluted waters, this P-170 glycoprotein pump also removes ‘new’ man-made toxic chemicals out of cells. Many chemical agents may alter the function of this fragile mechanism. A new class of compounds, referred to as ‘chemosensitizers’, deserve a top rank among environmentally-hazardous chemicals, since they block this basic natural defence mechanism. The authors measured the concentration of such MXR-inhibiting substances by two me…
Quality of life, alexithymia, and defence mechanisms in patients affected by breast cancer across different stages of illness
2016
Objectives: The aim of this study was to evaluate the effect of alexithymia and defence mechanisms on the quality of life of patients affected by breast cancer at different stages of the disease. Methods A convenience sample of 110 patients with breast cancer was involved in the study: 41 were receiving adjuvant chemotherapyafter surgery, 29 had disease-free survival in follow-up and 40 were receiving chemotherapy for metastatic disease. Quality of life, alexithymia and defence mechanisms were assessed using the following instruments: EORTC QLQ-C30-BR23, Toronto Alexithymia Scale (TAS-20) and Defense Mechanism Inventory (DMI). Results Compared to the other groups, patients receiving chemoth…
Elimination of a bacterial pore-forming toxin by sequential endocytosis and exocytosis
2008
Staphylococcus aureus alpha-toxin is the archetype of bacterial pore forming toxins and a key virulence factor secreted by the majority of clinical isolates of S. aureus. Toxin monomers bind to target cells and oligomerize to form small beta-barrel pores in the plasma membrane. Many nucleated cells are able to repair a limited number of lesions by unknown, calcium-independent mechanisms. Here we show that cells can internalize alpha-toxin, that uptake is essential for cellular survival, and that pore-complexes are not proteolytically degraded, but returned to the extracellular milieu in the context of exosome-like structures, which we term toxosomes.
Aberrant gene expression profiles in Mediterranean sea urchin reproductive tissues after metal exposures
2019
Abstract Marine organisms are simultaneously exposed to numerous pollutants, among which metals probably represent the most abundant in marine environments. In order to evaluate the effects of metal exposure at molecular level in reproductive tissues, we profiled the sea urchin transcriptional response after non-lethal exposures using pathway-focused mRNA expression analyses. Herein, we show that exposures to relatively high concentrations of both essential and toxic metals hugely affected the gonadic expression of several genes involved in stress-response, detoxification, transcriptional and post-transcriptional regulation, without significant changes in gonadosomatic indices. Even though …
Sesquiterpene volatile organic compounds (VOCs) are markers of elicitation by sulfated laminarine in grapevine
2015
SPE IPM UB CT1; International audience; Inducing resistance in plants by the application of elicitors of defense reactions is an attractive plant protection strategy, particularly for grapevine (Vitis vinifera), which is susceptible to severe fungal diseases. Although induced resistance (IR) can be successful under controlled conditions, in most cases, IR is not sufficiently effective for practical disease control under outdoor conditions. Progress in the application of IR requires a better understanding of grapevine defense mechanisms and the ability to monitor defense markers to identify factors, such as physiological and environmental factors, that can impact IR in the vineyard. Volatile…
Adversarial Attack’s Impact on Machine Learning Model in Cyber-Physical Systems
2020
Deficiency of correctly implemented and robust defence leaves Internet of Things devices vulnerable to cyber threats, such as adversarial attacks. A perpetrator can utilize adversarial examples when attacking Machine Learning models used in a cloud data platform service. Adversarial examples are malicious inputs to ML-models that provide erroneous model outputs while appearing to be unmodified. This kind of attack can fool the classifier and can prevent ML-models from generalizing well and from learning high-level representation; instead, the ML-model learns superficial dataset regularity. This study focuses on investigating, detecting, and preventing adversarial attacks towards a cloud dat…
Pensiero e difese nei disturbi bipolari. Studio clinico e psicopatologico su bipolari I e bipolari II. Thinking organization and defense mechanisms i…
2013
Obiettivi. Scopo del presente studio è esplorare il funzionamento psichico dei soggetti con disturbo bipolare I e II attraverso l’analisi e il confronto degli stili di pensiero e dei pattern difensivi. Metodi. Nel corso di un intero anno solare (2009-2010), presso la clinica Psichiatrica del Policlinico Universitario di Palermo sono stati reclutati 29 pazienti con disturbo bipolare I e II. È stato somministrato il seguente protocollo: Wechsler Adult Intelligent Scale-R (WAIS-R) per valutare il funzionamento cognitivo generale; Defense Mechanisms Inventory (DMI) per misurare i pattern difensivi. Sono stati quindi ana- lizzati e confrontati i risultati ai due reattivi. Risultati. I soggetti c…
Differences in parasite susceptibility and costs of resistance between naturally exposed and unexposed host populations
2009
It is generally assumed that resistance to parasitism entails costs. Consequently, hosts evolving in the absence of parasites are predicted to invest less in costly resistance mechanisms than hosts consistently exposed to parasites. This prediction has, however, rarely been tested in natural populations. We studied the susceptibility of three naïve, three parasitized and one recently isolated Asellus aquaticus isopod populations to an acanthocephalan parasite. We found that parasitized populations, with the exception of the isopod population sympatric with the parasite strain used, were less susceptible to the parasite than the naïve populations. Exposed but uninfected (resistant) isopods f…
Role of dioxygenase α-DOX2 and SA in basal response and in hexanoic acid-induced resistance of tomato (Solanum lycopersicum) plants against Botrytis …
2015
Resistance of tomato (Solanum Lycopersicum) to the fungal pathogen Botrytis cinerea requires complex interplay between hormonal signalling. In this study, we explored the involvement of new oxylipins in the tomato basal and induced response to this necrotroph through the functional analysis of the tomato α-dioxygenase2 (α-DOX2)-deficient mutant divaricata. We also investigated the role of SA in the defence response against this necrotrophic fungus using SA-deficient tomato nahG plants. The plants lacking dioxigenase α-DOX2, which catalyses oxylipins production from fatty acids, were more susceptible to Botrytis, and hexanoic acid-induced resistance (Hx-IR) was impaired; hence α-DOX2 is requ…