21 research outputs found
Risks of Sharing Cyber Incident Information
Incident information sharing is being encouraged and mandated as a way of improving overall cyber intelligence and defense, but its take up is slow. Organisations may well be justified in perceiving risks in sharing and disclosing cyber incident information, but they tend to express such worries in broad and vague terms. This paper presents a specific and granular analysis of the risks in cyber incident information sharing, looking in detail at what information may be contained in incident reports and which specific risks are associated with its disclosure. We use the STIX incident model as indicative of the types of information that might be reported. For each data field included, we identify and evaluate the threats associated with its disclosure, including the extent to which it identifies organisations and individuals. The main outcome of this analysis is a detailed understanding of which information in cyber incident reports requires protection, against specific threats with assessed severity. A secondary outcome of the analysis is a set of guidelines for disciplined use of the STIX incident model in order to reduce information security risk
Trust Evaluation Model Based on User Trust Cloud and User Capability in E-Learning Service
The Assessment of Distributed Photovoltaic Capacity Credit in Courts Considering High Penetration
Loss of glutaredoxin 3 impedes mammary lobuloalveolar development during pregnancy and lactation
Arabidopsis Glutaredoxin S17 Contributes to Vegetative Growth, Mineral Accumulation, and Redox Balance during Iron Deficiency
Iron (Fe) is an essential mineral nutrient and a metal cofactor required for many proteins and enzymes involved in the processes of DNA synthesis, respiration, and photosynthesis. Iron limitation can have detrimental effects on plant growth and development. Such effects are mediated, at least in part, through the generation of reactive oxygen species (ROS). Thus, plants have evolved a complex regulatory network to respond to conditions of iron limitations. However, the mechanisms that couple iron deficiency and oxidative stress responses are not fully understood. Here, we report the discovery that an Arabidopsis thaliana monothiol glutaredoxin S17 (AtGRXS17) plays a critical role in the plants ability to respond to iron deficiency stress and maintain redox homeostasis. In a yeast expression assay, AtGRXS17 was able to suppress the iron accumulation in yeast ScGrx3/ScGrx4 mutant cells. Genetic analysis indicated that plants with reduced AtGRXS17 expression were hypersensitive to iron deficiency and showed increased iron concentrations in mature seeds. Disruption of AtGRXS17 caused plant sensitivity to exogenous oxidants and increased ROS production under iron deficiency. Addition of reduced glutathione rescued the growth and alleviates the sensitivity of atgrxs17 mutants to iron deficiency. These findings suggest AtGRXS17 helps integrate redox homeostasis and iron deficiency responses
Quantitative Imaging of Glutathione in Live Cells Using a Reversible Reaction-Based Ratiometric Fluorescent Probe
Glutathione
(GSH) plays an important role in maintaining redox
homeostasis inside cells. Currently, there are no methods available
to quantitatively assess the GSH concentration in live cells. Live
cell fluorescence imaging revolutionized the field of cell biology
and has become an indispensable tool in current biological studies.
In order to minimize the disturbance to the biological system in live
cell imaging, the probe concentration needs to be significantly lower
than the analyte concentration. Because of this, any irreversible
reaction-based GSH probe can only provide qualitative results within
a short reaction time and will exhibit maximum response regardless
of the GSH concentration if the reaction is completed. A reversible
reaction-based probe with an appropriate equilibrium constant allows
measurement of an analyte at much higher concentrations and, thus,
is a prerequisite for GSH quantification inside cells. In this contribution,
we report the first fluorescent probeî—¸ThiolQuant Green (TQ
Green)î—¸for quantitative imaging of GSH in live cells. Due to
the reversible nature of the reaction between the probe and GSH, we
are able to quantify mM concentrations of GSH with TQ Green concentrations
as low as 20 nM. Furthermore, the GSH concentrations measured using
TQ Green in 3T3-L1, HeLa, HepG2, PANC-1, and PANC-28 cells are reproducible
and well correlated with the values obtained from cell lysates. TQ
Green imaging can also resolve the changes in GSH concentration in
PANC-1 cells upon diethylmaleate (DEM) treatment. In addition, TQ
Green can be conveniently applied in fluorescence activated cell sorting
(FACS) to measure GSH level changes. Through this study, we not only
demonstrate the importance of reaction reversibility in designing
quantitative reaction-based fluorescent probes but also provide a
practical tool to facilitate redox biology studies