Antimicrobial photodynamic therapy as a new approach for the treatment of vulvovaginal candidiasis: preliminary results.

In this work, we present the efficacy of photodynamic therapy against yeast cells in an animal model. We tested two photosensitizers, methylene blue and protoporphyrin IX. Thirty-seven female BALB-c mice with a body mass of 20-25 g were used. To achieve persistent vaginitis, estrus was induced by subcutaneous injection of 0.1 mg/mL estradiol valerate applied weekly. Three days after pseudo-estrus, intravaginal inoculation with Candida albicans was performed. Mice were anesthetized with ketamine (80 mg/kg) and xylazine (10 mg/kg) by intraperitoneal injection before inoculation, and antimicrobial photodynamic therapy (aPDT) was performed 5 days after fungal inoculation. Two photosensitizers were tested, methylene blue (MB; 100 µM) and protoporphyrin IX (PpNetNI; 10 µM). Two custom-made LEDs emitting light at 660 and 630 nm at approximately 800 mW each were used for irradiation. The aPDT treatment reduced the fungal colony-forming units (CFUs) by one order of magnitude for the MB (p = 0.020) and PpNetNI (p = 0.018) photosensitizers. Seven days after the treatment, there were significantly fewer CFUs compared to the control group (p = 0.041 and p = 0.035 for MB and PpNetNI, respectively), but this was not increased compared to the initial number immediately after aPDT. Using aPDT as a therapeutic option to decrease fungal infection in a vaginal candidiasis model resulted in a significant reduction in the C. albicans population. Both photosensitizers were effective for preventing reinfection within 7 days. The aPDT also had no effect on the vaginal mucosa at the ultrastructural level. In addition to the fungicide effect, we observed reduced swelling and lack of the formation of abscesses, microabscesses coating the cornified epithelial layer, and the accumulation of neutrophils in the submucosa.

Staining Beverages and Cigarette Smoke on Composite Resin and Human Tooth Fluorescence by Direct Spectrometry.

INTRODUCTION: This study evaluated the fluorescence intensity (FI) of different brands of composite resins (CRs) and compare those values with the FI of human tooth, under the action of cigarette smoke (CI), coffee (CA), and soft drink (CO), measured by direct spectrometry. MATERIALS AND METHODS: A total of 30 specimens of each brand (Filtek Z350, Esthet-X, Amelogen, Durafill) were made. Others 30 tooth specimens (3 mm/diameter) were obtained from human molars using a trephine bur. The specimens were randomly divided into three groups (n = 10), according to substances: CI, CA, CO. The FI was directly measured using an optic fiber associated with a spectrometer and was measured at baseline and after staining. Data were submitted to Kruskal-Wallis, Dunnett, and Dunn tests. RESULTS: Staining influenced FI mean values among CRs and between those with human tooth. Z showed the closest FI mean values of tooth after staining. CONCLUSION: Staining beverages and cigarette smoke negatively influenced on FI of CR and human tooth. CLINICAL SIGNIFICANCE: The study shows darkening treatments influenced on the fluorescent property of the dental tissues and restorative materials according to the direct spectrometry analysis.

Photodynamic action of protoporphyrin IX derivatives on Trichophyton rubrum.

BACKGROUND: Dermatophytes are filamentous keratinophilic fungi. Trichophyton rubrum is a prevalent infectious agent in tineas and other skin diseases. Drug therapy is considered to be limited in the treatment of such infections, mainly due to low accessibility of the drug to the tissue attacked and development of antifungal resistance in these microorganisms. In this context, Photodynamic Therapy is presented as an alternative. OBJECTIVE: Evaluate, in vitro, the photodynamic activity of four derivatives of Protoporphyrin IX by irradiation with LED 400 nm in T. rubrum. METHOD: Assays were subjected to irradiation by twelve cycles of ten minutes at five minute intervals. RESULT: Photodynamic action appeared as effective with total elimination of UFCs from the second irradiation cycle. CONCLUSION: Studies show that the photodynamic activity on Trichophyton rubrum relates to a suitable embodiment of the photosensitizer, which can be maximized by functionalization of peripheral groups of the porphyrinic ring.

Photodynamic action of protoporphyrin IX derivatives on Trichophyton rubrum

Abstract: BACKGROUND: Dermatophytes are filamentous keratinophilic fungi. Trichophyton rubrum is a prevalent infectious agent in tineas and other skin diseases. Drug therapy is considered to be limited in the treatment of such infections, mainly due to low accessibility of the drug to the tissue attacked and development of antifungal resistance in these microorganisms. In this context, Photodynamic Therapy is presented as an alternative. OBJECTIVE: Evaluate, in vitro, the photodynamic activity of four derivatives of Protoporphyrin IX by irradiation with LED 400 nm in T. rubrum. METHOD: Assays were subjected to irradiation by twelve cycles of ten minutes at five minute intervals. RESULT: Photodynamic action appeared as effective with total elimination of UFCs from the second irradiation cycle. CONCLUSION: Studies show that the photodynamic activity on Trichophyton rubrum relates to a suitable embodiment of the photosensitizer, which can be maximized by functionalization of peripheral groups of the porphyrinic ring.

Chlorophyllin-M: A new substance for photodynamic therapy in the retina and choroid.

BACKGROUND AND OBJECTIVE: Chlorophyllin-M is a new chlorophyll-based derivative photosensitive compound developed by our research group with easy laboratorial synthesis and ideal properties for photodynamic therapy (PDT). It is intended for clinical treatments with simple and low cost techniques and reagents. The objective of this study is to evaluate if intravenous chlorophyllin-M is able to deliver a photosensitizer to rabbit retina and rabbit choroid and promote PDT after ocular irradiation with a 660 nm LASER. METHODS: This is a pre-clinical study. Ten eyes of five pigmented Californian rabbits were included in the study. The right eyes served as the treatment group, and the left eyes served as the control group. All eyes had been ophthalmologically evaluated and were considered normal. RESULTS: Ophthalmic exam with anterior biomicroscopy, dilated fundus examination, and fluorescein angiography after the LASER procedure revealed normal anterior segment, retinal and choroid vessels occlusion, lumen narrowing, and capillary non-perfusion in the treated areas, indicating that PDT was successful in the treatment eyes group. CONCLUSION: The results of this pre-clinical study encourage future studies with this new compound. Chlorophyllin-M may become a new cost-effective agent in the retinal therapeutic arsenal.