Results 131 to 140 of about 2,990 (179)

Sonodynamically induced antitumor effect of pheophorbide a

Cancer Letters, 1996
The sonodynamically induced antitumor effect of pheophorbide a (Ph-a) was investigated. Both in vitro and in vivo effects on sarcoma 180 were tested in combination with ultrasound at 2 MHz. The rate of ultrasonically induced cell damage in air-saturated suspension was enhanced by twice with 80 microM Ph-a.
Koshiro Umemura, K Umemura, Ryuichiro Nishigaki   +2 more
exaly   +3 more sources

Photophysical studies of the pheophorbide a dimer

Journal of Photochemistry and Photobiology B: Biology, 2000
This work reports on a monomer-dimer equilibrium state of pheophorbide a in solution. A methodology for controlling the equilibrium constant by use of temperature and solvent variation is described. The absorption spectrum of the dimer is calculated, using different prepared equilibria of monomer and dimer in solution.
I, Eichwurzel, H, Stiel, B, Röder
openaire   +2 more sources

Characteristics of photosensitization of Pheophorbide a in liposomal media

Science in China Series C: Life Sciences, 1999
Pheophorbide a (PPa), a decomposition product of chlorophyll a, is a photosensitizer. The photosensitization mechanisms (Type I and Type 11) of PPa in simple buffer solutions and in buffer solutions containing double-layered DPPC liposomes have been studied using techniques of ESR, spin-trapping, spin-counteraction and laser flash photolysis.
H, Yang, M, Li, W, Zhang, H, Zhao, Z, Zhang   +4 more
openaire   +2 more sources

The synthesis of galactopyranosyl-substituted derivatives of pheophorbide

Russian Journal of Bioorganic Chemistry, 2000
New pheophorbide and pyropheophorbide derivatives containing carbohydrate fragments, derivatives of galactopyranose, were synthesized. Galactopyranosylpheophorbide and galactopyranosylpyropheophorbide with free hydroxyl groups were found to be water-soluble and useful as sensitizers in photodynamic therapy of cancer.
A A, Aksenova, Iu L, Sebiakin, A F, Mironov   +2 more
openaire   +2 more sources

Energy and electron transfer properties of methyl pheophorbide-a in zinc porphyrin-pheophorbide dyads

Tetrahedron, 1997
Abstract A series of ortho-, meta- and para-substituted zinc porphyrin-pheophorbide dyads were synthesized directly from methyl pheophorbide-a by trans-esterification of β-keto methyl ester with hydroxymethyl substituted porphyrins. Quantitative energy transfer occurred from the excited zinc porphyrin to the pheophorbide.
Satoshi Shinoda, Hiroshi Tsukube, Yoshinobu Nishimura, Iwao Yamazaki, Atsuhiro Osuka   +4 more
openaire   +1 more source

Derivatives of Pheophorbide‐a and Pheophorbide‐b from Photocytotoxic Piper penangense Extract

Chemistry & Biodiversity, 2011
AbstractIn our screening program for new photosensitizers from Malaysian biodiversity for photodynamic therapy (PDT) of cancer, MeOH extracts of ten terrestrial plants from Cameron Highlands in Pahang, Peninsular Malaysia, were tested. In a short‐term 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide (MTT) assay, 20 μg/ml each of these ...
Fadzly Adzhar, Kamarulzaman, Khozirah, Shaari, Anthony Siong Hock, Ho, Nordin Haji, Lajis, Soo Hwang, Teo, Hong Boon, Lee   +5 more
openaire   +2 more sources

The Chlorophyll Catabolite Pheophorbide a as a Photosensitizer for the Photodynamic Therapy

Current Medicinal Chemistry, 2012
Pheophorbide a is a clorophyll catabolite that recently has drawn the attention of several investigators for its potential in photodynamic therapy. In this review we summarize its photophysical properties, phototoxicity, cellular localization, biodistribution and PDT activity as a free or conjugated molecule.
Xodo L. E., Rapozzi V., ZACCHIGNA, MARINA, DRIOLI, Sara, ZORZET, SONIA   +4 more
openaire   +3 more sources

Photodynamic Imaging of a Rat Pancreatic Cancer with Pheophorbide a

Photochemistry and Photobiology, 1996
ABSTRACTLaser‐induced fluorescence of pheophorbide a (Ph‐a) was used for in vitro photodynamic imaging (PDI) of a rat pancreatic acinar tumor. A 400 nm excitation induced a 470 nm autofluorescence and a 678 nm dye fluorescence in tumors and their surrounding pancreas 24 h after a 9 mg kg−1 body weight Ph‐a intravenous administration.
Keller, P., Sowinska, M., Tassetti, V., Heisel, F., Hajri, A., Evrard, S., Miehe, J.A., Marescaux, J., Aprahamian, M.   +8 more
openaire   +3 more sources

Synthesis of boronated derivatives of pheophorbide a

Doklady Chemistry, 2008
294 Photodynamic therapy (PDT) [1] and boron neutron capture therapy (BNCT) [2] are promising clinical approaches enabling a local effect on a tumor with little if any damage to the healthy tissue around it. Both methods are based on the selective accumulation of photoand radiosensitizer in cancer cells and in situ production of high-energy particles ...
V. A. Ol’shevskaya, A. V. Zaitsev, A. N. Savchenko, E. G. Kononova, P. V. Petrovskii, V. N. Kalinin   +5 more
openaire   +1 more source

Synthesis and Properties of Pheophorbide-Quinone Compounds

Bulletin of the Chemical Society of Japan, 1992
Abstract New pheophorbide-quinone derivatives with a different kind of quinone moieties were synthesized by mixed anhydride method. The structures of these compounds were confirmed by UV, IR, 1H NMR, fluorescence, and mass spectra. Effective fluorescence quenching of the pheophorbide chromophores in the synthesized molecules was observed
Victor V Borovkov, Alexander A Gribkov, Andrei N Kozyrev, Alexander S Brandis, Akito Ishida, Yoshiteru Sakata   +5 more
openaire   +1 more source