Disease relevance of Photosensitivity Disorders

• Rapid electrophysiological changes leading to arrhythmias in the aerobic rat heart. Photosensitization studies with rose bengal-derived reactive oxygen intermediates [1].
• Effects of photosensitization by hematoporphyrin derivative on mitochondrial adenosine triphosphatase-mediated proton transport and membrane integrity of R3230AC mammary adenocarcinoma [2].
• Photosensitization of leukemia L1210 cells with diaziquone [3].
• The purpose of this study was to determine if photosensitization mediated by the fluorescent dye, merocyanine 540, could be used to preferentially kill murine neuroblastoma cells in simulated autologous remission marrow grafts [4].
• Mitochondria of human cultured ECs were selectively damaged by photosensitization of cells labeled with the mitochondrion-selective fluorescent dye 2-(4-dimethylaminostyryl)-1-methylpyridinium iodide under conditions that induced only low levels of toxicity during the time of the experiment [5].

High impact information on Photosensitivity Disorders

• This reaction is Ca2+-dependent when staining is performed in buffered iso-osmotic sucrose, Ca2+-independent when staining proceeds at high ionic strength, inhibited by La3+ and sodium Suramin, enhanced by controlled, low level photosensitization of cell-associated dye and essentially irreversible [6].
• A novel mechanism for the generation of superoxide anions in hematoporphyrin derivative-mediated cutaneous photosensitization. Activation of the xanthine oxidase pathway [7].
• These data provide in vivo evidence for the involvement of .O2- in DHE-mediated cutaneous photosensitization and suggest that these radicals are generated through the activation of the xanthine oxidase pathway [7].
• The administration of allopurinol and calcium channel blockers may thus offer new approaches for the treatment of cutaneous porphyrin photosensitization [7].
• Photosensitization to benoxaprofen not due to ultraviolet A alone [8].

Chemical compound and disease context of Photosensitivity Disorders

• Selective killing of leukemic cells by merocyanine 540-mediated photosensitization [9].
• This paper describes a method, designated "receptor-dependent photosensitization," by which the receptor-mediated endocytosis of low density lipoprotein (LDL) can be used to deliver a photosensitizing agent, pyrene, to cultured human and animal cells [10].
• Selective labeling of proteins in biological systems by photosensitization of 5-iodonaphthalene-1-azide [11].
• High sensitivity to MC 540-mediated photosensitization appears to be a property that is shared by other enveloped viruses [12].
• Glucose regulated protein induction and cellular resistance to oxidative stress mediated by porphyrin photosensitization [13].

Biological context of Photosensitivity Disorders

• Our results also show that administration of COX-2 inhibitors enhance in vitro photosensitization by increasing apoptosis and improve in vivo PDT responsiveness by decreasing expression of angiogenic and inflammatory molecules [14].
• Transcription factor NF-kappa B is activated by photosensitization generating oxidative DNA damages [15].
• PPME localization within the lysosomal membrane could explain why ceramide acted as second messenger in NF-kappaB activation by PPME photosensitization [16].
• The mechanism of photosensitization appears to involve energy absorption by Au-urine and Au-cytosine adducts which can then transfer energy to thymine residues [17].
• Deuterium oxide, which is known to increase the half-life of singlet oxygen, was found to enhance Pf-I-mediated lipid peroxidation but produced insignificant effects upon Pf-II-mediated photosensitization [18].

Anatomical context of Photosensitivity Disorders

• Injection of Photofrin II in vivo followed by preparation of tumor plasma membranes, which were subsequently exposed to light in vitro, produced no photosensitization of 5'-nucleotidase activity at any time studied (up to 72 h after Photofrin II administration) [19].
• Inhibition of the high affinity Fc receptor (Fc gamma RI) on human monocytes by porphyrin photosensitization is highly specific and mediated by the generation of superoxide radicals [20].
• This paper describes the mechanisms by which chlorpromazine photosensitizes damage to membranes, protein and DNA and compares them to the mechanisms of photosensitization by psoralens, porphyrins, dyes, and other molecules [21].
• Susceptibility to merocyanine 540-mediated photosensitization: a differentiation marker on murine hematopoietic progenitor cells [22].
• Detection of nearest neighbors to specific fluorescently tagged ligands in rod outer segment and lymphocyte plasma membranes by photosensitization of 5-iodonaphthyl 1-azide [23].

Gene context of Photosensitivity Disorders

• Thus, intracellular porphyrins synthesized from ALA are sufficient to elicit activation of p38 on photosensitization [24].
• Indeed, TRAF6 dominant negative mutant abolished NF-kappaB activation by PPME photosensitization, and TRAF2 dominant negative mutant was without any effect, and overexpression of IkappaB kinases increased gene transcription controlled by NF-kappaB [16].
• We have investigated the role of singlet oxygen, an ROS formed by photosensitization, in the regulation of survival signaling via the epidermal growth factor receptor (EGFR) [25].
• Our data show that photosensitization with the new photosensitizer 9-HPbD could induce the apoptotic death of MCF-7 breast cancer cell and that this death is mediated by stress-activated signal through JNK [26].
• We conclude that UVB preirradiation and photosensitization result in the generation of V beta 7+ Th2 cells that suppress contact photosensitivity by releasing IL-10 [27].

Analytical, diagnostic and therapeutic context of Photosensitivity Disorders

• The cyclobutane dimer photoproducts of dTpdC and dCpdT have been produced by acetophenone photosensitization and separated by reverse-phase HPLC [28].
• These observations of an associated response of PBGD and PPIX imply that PBGD may be a rate-limiting determinant for the efficacy of delta-ALA-induced photosensitization when used in photodynamic therapy [29].
• Virus inactivation in red cell concentrates by photosensitization with phthalocyanines: protection of red cells but not of vesicular stomatitis virus with a water-soluble analogue of vitamin E [30].
• We report the preliminary results of laser lithotripsy of cystine stones accomplished in 2 patients with the use of a new method of photosensitization [31].
• Cell cycle distribution of TF-1 cells, surviving MC540 or VB-BO photosensitization has been studied by flow cytometry analysis after staining with Hoechst 33342 and PI [32].

References