Search results for "active"

Optical security and encryption with totally incoherent light

2001

We present a method for securing and encrypting information optically by use of totally incoherent illumination. Encryption is performed with a multichannel optical processor working under natural (both temporal and spatially incoherent) light. In this way, the information that is to be secured can be codified by use of color signals and self-luminous displays. The encryption key is a phase-only mask, providing high security from counterfeiting. Output encrypted information is recorded as an intensity image that can be easily stored and transmitted optically or electrically. Decryption or authentication can also be performed optically or digitally. Experimental results are presented.

Hepatitis C virus (HCV) and autoimmune liver diseases

1992

Anti-HCV tests were positive in 18–45% of sera from patients with autoimmune chronic active hepatitis. High gammaglobulin levels may result in false positive results, however, some sera show true positivity. PCR testing of such sera is necessary in order to determine whether HCV is directly involved in specific forms of the disease.

Artesunate Activates Mitochondrial Apoptosis in Breast Cancer Cells via Iron-catalyzed Lysosomal Reactive Oxygen Species Production

2011

The antimalarial agent artesunate (ART) activates programmed cell death (PCD) in cancer cells in a manner dependent on the presence of iron and the generation of reactive oxygen species. In malaria parasites, ART cytotoxicity originates from interactions with heme-derived iron within the food vacuole. The analogous digestive compartment of mammalian cells, the lysosome, similarly contains high levels of redox-active iron and in response to specific stimuli can initiate mitochondrial apoptosis. We thus investigated the role of lysosomes in ART-induced PCD and determined that in MCF-7 breast cancer cells ART activates lysosome-dependent mitochondrial outer membrane permeabilization. ART impac…

Persistence of C-reactive protein increased levels and high disease activity are predictors of cardiovascular disease in patients with axial spondylo…

2022

AbstractAn accurate prediction of cardiovascular (CV) risk in patients with Axial Spondyloarthritis (axSpA) is a strong unmet need, as CV risk algorithms poorly perform in these subjects. The aim of this study was to establish whether the persistence of high C-reactive protein (CRP) and high disease activity may be considered predictive factors of CVD in axSpA. 295 patients without personal history of CVD, were consecutively enrolled in this study. To evaluate the relationship between CV events occurrence (fatal and non-fatal) and the persistence of increased CRP levels, ASDAS (Ankylosing Spondylitis Disease Activity Score) > 2.1, and BASDAI (Bath Ankylosing Spondylitis Disease Activity)…

The inhibition of Ca2+-ATPases of human erythrocyte membranes by covalent binding of ATP derivatives.

1982

Amphiphilic Polysaccharide Block Copolymers for pH-Responsive Micellar Nanoparticles

2017

A full polysaccharide amphiphilic block copolymer was prepared from end group-functionalized dextrans using copper-mediated azide-alkyne click chemistry. Sufficient modification of the reducing end in both blocks was achieved by microwave-enhanced reductive amination in a borate-buffer/methanol solvent system. The combination of a hydrophilic dextran block with a hydrophobic acetalated dextran block results in an amphiphilic structure that turns water-soluble upon acid treatment. The material has a low critical micelle concentration and self-assembles in water to spherical micellar nanoparticles. The formed nanoparticles have a narrow size distribution below 70 nm in diameter and disassembl…

Role of oxygen and nitrogen species in experimental uveitis: anti-inflammatory activity of the synthetic antioxidant ebselen.

2002

This study was aimed at examining the role of oxygen and nitrogen reactive species in a model of experimental uveitis upon intravitreal injection of bacterial endotoxin to albino New Zealand rabbits. The inflammatory response was evaluated in terms of: (i) the integrity of the blood aqueous barrier (protein and cell content in samples of aqueous humor), (ii) histopathological changes of the eyes, (iii) clinical evaluation (with a score index based on clinical symptoms), and (iv) the concentration of malondialdehyde (MDA), in aqueous humor, as a marker of oxidative stress. Betamethasone was used as reference treatment, superoxide dismutase as quencher of superoxide anion, L-N(G)-nitro-L-argi…

Single-dose ebselen does not afford sustained neuroprotection to rats subjected to severe focal cerebral ischemia

2004

Oxygen free radicals have been involved in the pathophysiology of cerebral ischemia, especially after spontaneous or thrombolytic reperfusion. In this study with rats, we have combined a severe focal ischemic insult (2 h) and a prolonged reperfusion time (7 days) to assess the possible sustained neuroprotective effect of ebselen (10 or 100 mg/kg), a small, lipophilic organoselenium compound which mimics glutathione peroxidase. Parietal cortical perfusion was measured by laser-Doppler flowmetry, and focal cerebral ischemia was carried out by the intraluminal thread method. We have measured plasma selenium levels, brain reduced glutathione levels, as a marker of oxidative stress, and infarct …

Investigations concerning the COX/5-LOX inhibiting and hydroxyl radical scavenging potencies of novel 4,5-diaryl isoselenazoles

2007

The aim of this study was to investigate 4,5-diaryl isoselenazoles as multiple target non-steroidal anti-inflammatory drugs (MTNSAIDs) which can intervene into the inflammatory processes via different mechanisms of action creating a new class of compounds. Here we describe the synthesis of COX/LOX inhibitors which additionally reduce the level of reactive oxygen species, such as hydroxyl radicals which are well known for supporting inflammation processes in Parkinson's disease, Alzheimer's disease and rheumatoid arthritis.

Family Matters : Abusing Family Refresh Tokens to Gain Unauthorised Access to Microsoft Cloud Services Exploratory Study of Azure Active Directory Fa…

2022

Azure Active Directory (Azure AD) is an identity and access management service used by Microsoft 365 and Azure services and thousands of third-party service providers. Azure AD uses OIDC and OAuth protocols for authentication and authorisation, respectively. OAuth authorisation involves four parties: client, resource owner, resource server, and authorisation server. The resource owner can access the resource server using the specific client after the authorisation server has authorised the access. The authorisation is presented using a cryptographically signed Access Token, which includes the identity of the resource owner, client, and resource. During the authorisation, Azure AD assigns Ac…