Search results for "Photochemotherapy"
showing 10 items of 60 documents
Photodynamic therapy in the treatment of aggressive periodontitis: a systematic review
2015
Background: Aggressive periodontitis (AgP) is a severe form of periodontal diseases with rapid destruction of the supporting bone around teeth. The efficacy of PDT in suppressing periodontal pathogens may be crucial in adopting new protocols for the treatment of AgP. Thus, the aim of this systematic review was to investigate the possible role of PDT in the treatment of AgP as an adjunctive therapy or monotherapy. Material and Methods: A systematic search of the literature was performed. Additionally, the references from all the selected full-text studies were searched for relevant articles. Two reviewers screened independently titles and abstracts or full text copies. Quality assessment of …
SYNTHESIS OF PYRROLO[3,2-H]QUINOLINONES WITH GOOD PHOTOCHEMOTHERAPEUTIC ACTIVITY AND NO DNA DAMAGE
2010
In the search for new photochemotherapeutic agents, a series of derivatives of the ring system pyrrolo[3,2-h]quinoline--bioisosters of the angular furocoumarin angelicin--were synthesized through a four-step synthetic approach, in reasonable overall yields. Eight of the synthesized derivatives showed a remarkable phototoxicity against a panel of four human tumor cell lines and a great dose UV-A dependence, reaching IC₅₀ values at submicromolar level. The mode of cellular death photoinduced by pyrrolo[3,2-h]quinolines was evaluated through a series of flow cytometric analysis and other tests were performed to clarify their mechanism of action.
An in vitro model to study cellular photosensitizer uptake and photodynamic dose-response relationships of tumor cells
1993
Cellular fluorescence intensity (CFI) after incubation with varying concentrations of the photosensitizer Photofrin and the photodynamically induced dose-response relationships of hamster melanoma cells (A-MEL-3) were studied in a recently developed in vitro model. After administration of Photofrin to the extracellular serum-free medium, CFI was evaluated by flow cytometry together with constantly fluorescing latex particles used as a reference. After 5 min, 50% of maximal CFI was found, and after 60 min CFI was maximal. No further increase was obtained during the exposure to Photofrin over the incubation period of 4 h. During this plateau phase, CFI was significantly related to the concent…
Efficacy of photodynamic therapy in vulvar lichen sclerosus treatment based on immunohistochemical analysis of CD34, CD44, myelin basic protein, and …
2010
Introduction:Lichen sclerosus (LS) is a chronic skin and mucosa inflammatory disease. It affects mainly the female anogenital area especially in postmenopausal period. The main symptoms include pruritus, burning, pain, sometimes urinary problems, or difficulties in defecation. Usually, porcelain-white plaques are seen in the skin and mucosa. The etiology and pathogenesis of LS are still uncertain. There are some research studies on possible genetic predisposition, yet autoimmune, hormonal, or infectious factors are not excluded. The typical treatment of LS is mainly pharmacological, although the alternative treatment method used in LS is photodynamic therapy (PDT), which is noninvasive tech…
Synthesis and photocytotoxic activity of [1,2,3]triazolo[4,5-h][1,6]naphthyridines and [1,3]oxazolo[5,4-h][1,6]naphthyridines
2018
Abstract [1,2,3]Triazolo[4,5-h][1,6]naphthyridines and [1,3]oxazolo[5,4-h][1,6]naphthyridines were synthesized with the aim to investigate their photocytotoxic activity. Upon irradiation, oxazolo-naphtapyridines induced light-dependent cell death at nanomolar/low micromolar concentrations (EC50 0.01–6.59 μM). The most photocytotoxic derivative showed very high selectivity and photocytotoxicity indexes (SI = 72–86, PTI>5000), along with a triplet excited state with exceptionally long lifetime (18.0 μs) and high molar absorptivity (29781 ± 180 M−1cm−1 at λmax 315 nm). The light-induced production of ROS promptly induced an unquenchable apoptotic process selectively in tumor cells, with mitoch…
Modification of Structural and Luminescence Properties of Graphene Quantum Dots by Gamma Irradiation and Their Application in a Photodynamic Therapy
2015
Herein, the ability of gamma irradiation to enhance the photoluminescence properties of graphene quantum dots (GQDs) was investigated. Different doses of gamma-irradiation were used on GQDs to examine the way in which their structure and optical properties can be affected. The photoluminescence quantum yield was increased six times for the GQDs irradiated with high doses compared to the nonirradiated material. Both photoluminescence lifetime and values of optical band gap were increased with the dose of applied gamma irradiation. In addition, the exploitation of the gamma-irradiated GQDs as photosensitizers was examined by monitoring the production of singlet oxygen under UV illumination. T…
Multicompartment Micelles with Adjustable Poly(ethylene glycol) Shell for Efficient in Vivo Photodynamic Therapy
2014
We describe the preparation of well-defined multicompartment micelles from polybutadiene-block-poly(1-methyl-2-vinyl pyridinium methyl sulfate)-block-poly(methacrylic acid) (BVqMAA) triblock terpolymers and their use as advanced drug delivery systems for photodynamic therapy (PDT). A porphyrazine derivative was incorporated into the hydrophobic core during self-assembly and served as a model drug and fluorescent probe at the same time. The initial micellar corona is formed by negatively charged PMAA and could be gradually changed to poly(ethylene glycol) (PEG) in a controlled fashion through interpolyelectrolyte complex formation of PMAA with positively charged poly(ethylene glycol)-block-p…
A novel pro-apoptotic role of zinc octacarboxyphthalocyanine in melanoma me45 cancer cell's photodynamic therapy (PDT)
2018
Abstract Zn-based phthalocyanine acts as drug or photosensitizer in photodynamic therapy (PDT) for the treatment of cancer cells. The activated zinc octacarboxyphthalocyanine (ZnPcOC) reacts with oxygen, to generate reactive oxygen species for the damage of melanoma cancer cells, Me45. This in vitro study aimed at investigating the cytotoxic effects of different concentrations of ZnPcOC activated with a diode laser (λ = 685 nm) on Me45, and normal human fibroblast cells, NHDF. To perform this study 104 cells/ml were seeded in 96-well plates and allowed to attach overnight, after which cells were treated with different concentrations of ZnPcOC (10, 20 and 30 μM). After 4 h, cells were irradi…
Pyrrolo[3,4-h]quinolinones a new class of photochemotherapeutic agents
2011
Abstract Pyrrolo[3,4- h ]quinolin-2-ones were synthesized as nitrogen isosters of the angular furocoumarin angelicin, with the aim of obtaining new photochemotherapeutic agents with increased antiproliferative activity and lower undesired toxic effects. A versatile synthetic pathway was approached to allow the isolation of derivatives of the new ring system with a good substitution pattern on the pyrrole moiety. Photobiological screenings of the new compounds revealed a potent phototoxic effect and a great UVA dose dependence, reaching IC 50 values at submicromolar level. The induced cellular photocytotoxicity was related to apoptosis with the involvement of mitochondria and lysosomes, alte…