sret

Hiber Acquires Srett Industrie

Hiber Acquires Srett Industrie to Accelerate the Roll-Out of Environmental and Integrity Solutions.




sret

Bisretinoid phospholipid and vitamin A aldehyde: Shining a light [Thematic Reviews]

Vitamin A aldehyde covalently bound to opsin protein is embedded in a phospholipid-rich membrane that supports photon absorption and phototransduction in photoreceptor cell outer segments. Following absorption of a photon, the 11-cis-retinal chromophore of visual pigment in photoreceptor cells isomerizes to all-trans-retinal. To maintain photosensitivity 11-cis-retinal must be replaced. At the same time, however, all-trans-retinal has to be handled so as to prevent nonspecific aldehyde activity. Some molecules of retinaldehyde upon release from opsin are efficiently reduced to retinol. Other molecules are released into the lipid phase of the disc membrane where they form a conjugate (N-retinylidene-PE, NRPE) through a Schiff base linkage with phosphatidylethanolamine (PE). The reversible formation of NRPE serves as a transient sink for retinaldehyde that is intended to return retinaldehyde to the visual cycle. However, if instead of hydrolyzing to PE and retinaldehyde, NRPE reacts with a second molecule of retinaldehyde a synthetic pathway is initiated that leads to the formation of multiple species of unwanted bisretinoid fluorophores. We report on recently identified members of the bisretinoid family some of which differ with respect to the acyl chains associated with the glycerol backbone. We discuss processing of the lipid moieties of these fluorophores in lysosomes of retinal pigment epithelial (RPE) cells, their fluorescence characters and new findings related to light and iron-associated oxidation of bisretinoids.




sret

Bisretinoid phospholipid and vitamin A aldehyde: Shining a light [Thematic Reviews]

Vitamin A aldehyde covalently bound to opsin protein is embedded in a phospholipid-rich membrane that supports photon absorption and phototransduction in photoreceptor cell outer segments. Following absorption of a photon, the 11-cis-retinal chromophore of visual pigment in photoreceptor cells isomerizes to all-trans-retinal. To maintain photosensitivity 11-cis-retinal must be replaced. At the same time, however, all-trans-retinal has to be handled so as to prevent nonspecific aldehyde activity. Some molecules of retinaldehyde upon release from opsin are efficiently reduced to retinol. Other molecules are released into the lipid phase of the disc membrane where they form a conjugate (N-retinylidene-PE, NRPE) through a Schiff base linkage with phosphatidylethanolamine (PE). The reversible formation of NRPE serves as a transient sink for retinaldehyde that is intended to return retinaldehyde to the visual cycle. However, if instead of hydrolyzing to PE and retinaldehyde, NRPE reacts with a second molecule of retinaldehyde a synthetic pathway is initiated that leads to the formation of multiple species of unwanted bisretinoid fluorophores. We report on recently identified members of the bisretinoid family some of which differ with respect to the acyl chains associated with the glycerol backbone. We discuss processing of the lipid moieties of these fluorophores in lysosomes of retinal pigment epithelial (RPE) cells, their fluorescence characters and new findings related to light and iron-associated oxidation of bisretinoids.




sret

FreeBSD Intel SYSRET Privilege Escalation

This Metasploit module exploits a vulnerability in the FreeBSD kernel, when running on 64-bit Intel processors. By design, 64-bit processors following the X86-64 specification will trigger a general protection fault (GPF) when executing a SYSRET instruction with a non-canonical address in the RCX register. However, Intel processors check for a non-canonical address prior to dropping privileges, causing a GPF in privileged mode. As a result, the current userland RSP stack pointer is restored and executed, resulting in privileged code execution.