Search results for "Photochemotherapy"
showing 10 items of 60 documents
Porphyrin and phthalocyanine photosensitizers designed for targeted photodynamic therapy of colorectal cancer
2020
Colorectal cancer is of particular concern due to its high mortality rate count. Recent investigations on targeted phototherapy involving novel photosensitizers and drug-delivery systems have provided promising results and realistic prospects for a successful medical treatment. New research trends have been focused particularly on development of advanced molecular systems offering effective photoactive species which could be selectively delivered directly into the affected cells. Porphyrins and phthalocyanines have been considered extremely attractive for this purpose due to their molecular versatility, excellent photochemical properties and multifunctional nature. In this review it has bee…
Double stimuli-responsive polysaccharide block copolymers as green macrosurfactants for near-infrared photodynamic therapy
2019
The NIR absorbing photosensitizer phthalocyanine zinc (PC(Zn)) was stabilized in aqueous media as water-dispersible nanoparticles with a reduction- and pH-responsive full polysaccharide block copolymer. A cellular uptake and also photo switchable intracellular activity of the cargo upon irradiation at wavelengths in the near infrared region were shown. The block copolymer was synthesized by applying a copper-free click strategy based on a thiol exchange reaction, creating an amphiphilic double-stimuli-responsive mixed disulfide. The dual-sensitive polysaccharide micelles represent a non-toxic and biodegradable green macrosurfactant for the delivery of phthalocyanine zinc. By encapsulation i…
Keratoacanthoma Centrifugum Marginatum (KCM) after photodynamic therapy with good response to oral retinoids and topical 5‐fluorouracil
2019
Keratoacanthoma centrifugum marginatum (KCM) is a rare variant of keratoacanthoma (KA), characterized by progressive peripheral growth, and usually devoid of deep invasion. Different systemic (oral retinoids) or topical treatments have been reported, but there is not a well-defined therapeutic protocol. We report the case of a KCM developing after photodynamic therapy (PDT) on the right leg of a 64-year-old woman. It was treated successfully with oral acitretin combined with topical 5-Fluorouracil + salicylic acid for 5 months. This is the first case of KCM developing after PDT and successfully treated with oral retinoid combined with topical treatment.
Yellow (577 nm) micropulse laser versus half-dose verteporfin photodynamic therapy in eyes with chronic central serous chorioretinopathy: results of …
2018
PurposeTo compare the functional and anatomical outcomes of eyes with chronic central serous chorioretinopathy treated with yellow micropulse (MP) laser versus half-dose verteporfin photodynamic therapy (PDT).MethodsThis is a multicentre, retrospective comparative study of 92 eyes treated with yellow MP laser (duty cycle of 5%, zero spacing between spots, spot size varied from 100 to 200 µm, power varied from 320 to 660 mW, and the pulse burst duration was 200 ms) and 67 eyes treated with PDT (half-dose verteporfin (3 mg/m2) infused over 10 min), followed by laser activation for 83 s. Spot sizes varied from 400 to 2000 µm.ResultsIn the MP group, at 12 months of follow-up, the mean best corr…
Dual Cherenkov Radiation-Induced Near-Infrared Luminescence Imaging and Photodynamic Therapy toward Tumor Resection
2020
International audience; Cherenkov radiation (CR), the blue light seen in nuclear reactors, is emitted by some radiopharmaceuticals. This study showed that (1) a portion of CR could be transferred in the region of the optical spectrum, where biological tissues are most transparent: as a result, upon radiance amplification in the near-infrared window, the detection of light could occur twice deeper in tissues than during classical Cherenkov luminescence imaging and (2) Cherenkov-photodynamic therapy (CR-PDT) on cells could be achieved under conditions mimicking unlimited depth using the CR-embarked light source, which is unlike standard PDT, where light penetration depth is limited in biologi…
Combined hyperthermia and chlorophyll-based photodynamic therapy: tumour growth and metabolic microenvironment
2003
The effects of combined and simultaneously applied localised 43 degrees C hyperthermia (HT) and an antivascular bacteriochlorophyll-serine-based photodynamic therapy (Bchl-ser-PDT) on tumour growth and several microenvironmental parameters were examined. Rats bearing DS-sarcomas were allocated to treatment groups: (i) sham-treatment (control), (ii) Bchl-ser-PDT (20 mg kg(-1) i.v.), (iii) localised HT, (iv) Bchl-ser-PDT+HT. The light source used was an infrared-A irradiator, which, by use of appropriate filters, delivered the different ranges of wavelengths required. Following treatment, tumour volume was monitored. The greatest tumour growth inhibition was seen with Bchl-ser-PDT+HT, and sub…
Hot Topic Water-filtered infrared-A radiation: a novel technique for localized hyperthermia in combination with bacteriochlorophyll-based photodynami…
1999
A novel application of an infrared-A (IR-A) radiation source equipped with a water-filter in the radiation path is described, which allows for tumour treatment with a simultaneous combination of localized hyperthermia (HT) and bacteriochlorophyll-serine (Bchl-ser) based photodynamic therapy (PDT). Using this system, the IR-A radiation was used to heat tumours to 43 degrees C for 60 min, while at the same time activating the Bchl-ser which was injected i.v. at a dose of 20 mg/kg, 10 min following commencement of HT. The growth of tumours undergoing this combined therapy was compared to that of tumours undergoing HT alone or sham-treated controls. Within the 90 day observation period, 100% of…
Photodynamic therapy within edematous brain tissue: Considerations on sensitizer dose and time point of laser irradiation
1996
Photosensitizer is known to spread with vasogenic edema fluid arising from a cerebral lesion (Neurosurg 33:1075-1082, 1993), which may be essential for sensitizing malignant cells outside the main tumor mass. The present experiments seek to elucidate whether resultant necrosis of perifocal brain tissue after laser irradiation follows a corresponding time pattern and whether damage depends on the photosensitizer dose. Male Wistar rats were anaesthetized with chloralhydrate for venous cannulation, craniotomy and focal cold lesion in order to induce vasogenic edema. Simultaneously, Photofrin II (PF II) was administered at a dose of 5 mg kg-1. The animals were re-anaesthetized after either 4, 1…
Kinetics of Photofrin II in perifocal brain edema.
1993
Photodynamic therapy is under intense investigation as a possible adjuvant for the treatment of malignant tumors of the central nervous system. It relies on the fact that photosensitizers are selectively taken up or retained by malignant tissue. However, most brain tumors are accompanied by substantial vasogenic edema as a consequence of blood-brain barrier disruption within the tumor, leading to extravasation and propagation of plasma constituents into the surrounding brain tissue. Systemically administered photosensitizers may enter healthy tissue together with the edema fluid, possibly leading to sensitization of tissues outside the tumor. To test this hypothesis, vasogenic edema was ind…
Ablative fractional laser-assisted photodynamic therapy for lentigo maligna: a prospective pilot study.
2019
Background Lentigo maligna (LM) is an in‐situ form of melanoma carrying a risk of progression to invasive lentigo maligna melanoma (LMM). LM poses a clinical challenge, with subclinical extension and high recurrence rates after incomplete surgery. Alternative treatment methods have been investigated with varying results. Photodynamic therapy (PDT) with methylaminolaevulinate (MAL) has already proved promising in this respect. Objectives To investigate the efficacy of ablative fractional laser (AFL)‐assisted PDT with 5‐aminolaevulinic acid nanoemulsion (BF‐200 ALA) for treating LM. Methods In this non‐sponsored, prospective pilot study ten histologically verified LMs were treated with AFL‐as…