Photodiagnosis and photodynamic therapy最新文献

Objective: This randomized controlled trial aimed to evaluate the bleaching efficacy and tooth sensitivity (TS) of participants submitted to different application protocols of in-office bleaching with violet light using 6% hydrogen peroxide (HP) nanoparticulate photocatalyst gel.

Materials and methods: Sixty-six participants were randomized and bleached using either a 6% HP (Nano White, DMC), and/or violet light (Bright Max Whitening, MMOptics), according to the following protocols: 1) only violet light (VIOL); 2) only bleaching gel application (BG) and; 3) combined bleaching gel application + violet light (BG+VIOL). The bleaching efficacy was evaluated with the Vita Easyshade spectrophotometer, Vita Classical and Vita Bleachedguide scales. The risk and intensity of TS were recorded using a 0-10 visual analogue scale (VAS) and a 0-4 numerical scale (NRS). Color change and intensity of TS values were compared using one-way ANOVA and Tukey's test were used. The absolute risk of TS was compared using the Chi-square test (α = 0.05).

Results: A significant and higher degree of bleaching was observed in the BG and BG+VIOL groups compared to the VIOL group (p < 0.003). Despite no significant differences in the risk (p > 0.07) and intensity (p > 0.28) of TS among groups, a higher risk of TS was observed in the BG and BG+VIOL groups.

Conclusions: Using VIOL reduced the risk of TS but did not improve bleaching. However, BG+VIOL with low-concentration HP nanoparticulate photocatalyst gel achieved equal efficacy and was less likely to cause TS compared to BG.

Objective: Antimicrobial photodynamic therapy (aPDT) is considered a potential treatment for biofilm infections, which have become an increasing health issue because of the rise in antimicrobial resistance. This study aimed to evaluate the bactericidal effect of aPDT using indocyanine green-loaded nanospheres with chitosan coating (ICG-Nano/c) against polymicrobial periodontal biofilms.

Methods: Composite biofilms of Porphyromonas gingivalis and Streptococcus gordonii were constructed in 96-well plates, and aPDT with ICG-Nano/c and an 810 nm diode laser was performed either by direct irradiation or transmitting irradiation through a 3-mm-thick gingival model. The efficacy of ICG-Nano/c-based aPDT was compared with antibiotics (minocycline and amoxicillin). Additionally, attenuated aPDT under sublethal conditions was used to investigate gene expression related to the antioxidant response (oxyR and sod of P. gingivalis) and biofilm formation via quorum sensing (luxS of both species) with real-time polymerase chain reaction.

Results: ICG-Nano/c-based aPDT significantly reduced the bacterial load in the biofilm, achieving at least a 2 log₁₀ reduction in colony-forming units within 5 minutes for both irradiation methods. After 6 hours of treatment, the bactericidal effects of aPDT and antibiotics were similar, but after 32 hours, antibiotics were more effective, particularly against P. gingivalis. Attenuated aPDT showed a slight increase in sod expression in P. gingivalis, while luxS expression decreased in both bacteria.

Conclusion: The ICG-Nano/c-based aPDT system exerted a certain degree of bactericidal activity against a composite biofilm of periodontal bacteria. Therefore, it has potential as an alternative option or adjunctive therapy to conventional antibiotics in periodontal treatment.

A 28-year-old female patient, diagnosed with stage IA1 cervical cancer, received PDT treatment with intravenous injection of Hiporfin, a HpD type photosensitizer. The patient's human papillomavirus (HPV) and cytology testing results were negative at the 3-month. At 6 months, the lesions on the cervical surface and within the cervical canal had completely resolved. There were no signs of recurrence or HPV infection during the 12-month follow-up period. There were no serious adverse events reported during or after the PDT treatment.

Aims: Assessment of the impact of different dentin bio-modifiers i.e., Bromelain, Riboflavin photosensitizer (RFP/Ultraviolet-A), and Chitosan nanoparticles (CHNPs) on the shear bond strength (SBS) and microleakage of composite bonded to acid etched carious affected dentin (CAD).

Materials and methods: Sixty-four human molars in which carious lesions extend till the middle third of the dentin were included. The infected dentin was removed and CAD was exposed. All specimens were categorized into four groups based on the application of dentin bio-modifier (n=16) Group 1 (No dentin modifier), Group 2 (Bromelain), Group 3 (RFP/UVA), and Group 4 (CHNPs). Dental adhesive application and composite buildup were performed. A dye penetration test was used to assess marginal leakage. Resin CAD interface assessment was performed using SEM. For SBS and failure pattern analysis, a universal testing machine and stereomicroscope were used respectively. One-way ANOVA followed by Bonferroni's posthoc test was employed to analyze the differences among various groups (p ≤ 0.05) RESULTS: The lowest microleakage (13.27 ± 0.10) and highest SBS (11.64 ± 0.16 MPa) were observed in Group 2 (Bromelain). However, the maximum values of marginal leakage (37.21 ± 0.21) and minimum SBS (7.34 ± 0.07 MPa) were detected in Group 1 samples. The length of resin tags in the Group 2 specimens (Bromelain) was found to be the highest (102.11 ± 5.12μm)^. However, Group 1 (No modifier) exhibited the lowest resin tag length (50.45 ± 2.37 μm).

Conclusion: Caries-affected dentin modified with Bromelain resulted in satisfactory SBS with minimal microleakage scores. Chitosan nanoparticles and RFP/Ultraviolet-A also presented better outcomes in terms of microleakage and SBS than the control.

Background: While 5-Aminolevulinic acid photodynamic therapy (ALA-PDT) is widely used to treat actinic keratosis (AK), treatment resistance and recurrence after ALA-PDT remain significant clinical challenges.

Methods: This single-site, retrospective, matched case-control study included 119 patients with histologically confirmed AK to identify clinical and pathological predictors for effectiveness of ALA-PDT. Patients received four consecutive ALA-PDT sessions at intervals of 1 or 2 weeks. Initial complete clearance (ICC) at 3 months and sustained complete clearance (SCC) at 12 months were assessed. Case patients were those with treatment-resistant or recurrent AK, matched with controls based on age, sex, and the treatment date. Baseline characteristics were collected and compared between the case and control groups.

Results: ICC at 3 months was achieved in 106 out of 119 patients (89.07%), with 65 out of 82 patients (79.27%) maintaining SCC at 12 months. Pigmented AK emerged as an independent predictor of treatment resistance (OR=44.05, p=0.00). Furthermore, follicular extension to the isthmus or deeper was significantly associated with recurrence within 1 year (OR=17.26, p=0.00).

Conclusion: Pigmented AK and AK with follicular extension to the isthmus or deeper may serve as independent predictors of treatment resistance and recurrence, respectively. These findings highlight the importance of these specific features when assessing prognosis and tailoring treatment strategies for individual AK patients.

Photodynamic therapy is a curative treatment of human papillomavirus-associated diseases that provides a selective effect leading to the destruction of pathological cells containing the virus. The retrospective study aimed to determine the role of systemic inflammatory reaction induced by photodynamic stimulation in low- and high-squamous intraepithelial lesion treatment.

Methods: 143 patients with confirmed human papillomavirus-associated cervical intraepithelial neoplasia underwent photodynamic therapy with Photolon and activation in the range of 662 nm. All patients underwent colposcopy, histologic study, HPV DNA analysis, CBC, and immunogram. The chi-square criterion was used to evaluate differences before, 5 days post, and 3 months after PDT; a P value <0.05 was considered significant.

Results: A complete regression in patients with low-squamous intraepithelial lesion (n=117) was achieved 3 months after PDT in 89.7% of cases (105/117) while it persisted in 12 patients. Complete regression in patients with high-squamous intraepithelial lesion (n=26) was achieved in 92.3% (24/26), one patient retained with the lesion, and another one had partial regression in the form of lower grade lesion. On the 5th day post-PDT, the formation of dense fibrin in photodynamic effect was noted on colposcopy, and changes in CBC, accompanied by statistically significant neutrocytosis, increased ESR and other indicators of reactive inflammation were recorded. Patients noted increased body temperature up to 37.8±0.5°C in 88% of cases.

Conclusion: One of the mechanisms of PDT`s antitumor and antiviral action is the development of acute inflammation in response to cytotoxic action on cells and vascular response in the form of pathological area devascularization. Such reactive inflammation activates all parts of the immune system. Changes on day 5 post-PDT in inflammatory parameters in CBC and IL-1, IL-6 and TNF-α markers correlate with the clinical picture of the post-photodynamic effect.

Background: Effective management of cutaneous nocardiosis is hampered by the lack of defined treatment recommendations and frequently requires prolonged antibiotic therapy.

Case presentation: This report describes a case of cutaneous nocardiosis who was effectively treated in a brief amount of time with three sessions of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in conjunction with antibiotics.

Conclusion: ALA-PDT combined with antibiotics can effectively treat refractory cutaneous nocardiosis.

Photodynamic therapy (PDT) is a minimally invasive therapy for treating cancers, infectious diseases and several other conditions. It uses light as an activator and component called photosensitizer. Hypericin is a natural photosensitizer which garnered a lot of attention due to its potential use in PDT for cancer treatment. Historically, hypericin has been used for millennia in herbal therapy because of its antiviral and antidepressant properties. However, the traditional synthesis of hypericin requires certain chemicals that are harmful to the environment and human health. To overcome this problem, scientists have been working towards the developing a green synthesis approach for producing hypericin. This study focuses on the green synthesis and assessment of the photosensitizer hypericin from the dried leaves of Hypericum perforatum (St. John's Wort) and its photodynamic efficacy were evaluated in in vitro using MCF7 breast cells. An eco-friendly method was employed for extracting and purifying the hypericin.. This green synthesis approach uses fewer chemicals and solvents that minimize the hazard to the environment and health. The formation of hypericin was characterized using FTIR and UV-Vis-NIR spectrophotometers and the morphology was analyzed by HRTEM. The FTIR spectrum confirmed the presence of hydroxyl and carbonyl groups and the UV-Vis-NIR peaks exhibited the characterstic absorption peak at 589nm. The spherical shaped morphology was seen in HRTEM. As hypericin is hydrophobic in nature, polyvinylpyrrolidone (PVP), a biodegradable, non-toxic material makes the former hydrophilic by producing hypericin-PVP compound. MTT assay and AO-EB staining assay established that hypericin exhibited the highest cell death in MCF7 cancer cells via apoptosis. The results demonstrate hypericin's efficacy in inducing cancer cell death through apoptosis and oxidative stress. Thus, hypericin proved its potential to be a promising natural photosensitizer in the future.

Purpose: To evaluate the impact of repeated low-level red-light (RLRL) therapy on choroidal thickness and blood flow in pediatric myopia.

Methods: A three-month trial (April 1, 2023 - September 30, 2023) was conducted involving 44 children (ages 6-16) with myopia. Participants underwent RLRL therapy at home twice daily for five days per week, with each session lasting three minutes. Assessments at baseline, one month, and three months included cycloplegic refraction, best-corrected visual acuity (BCVA), intraocular pressure (IOP), ocular biometrics, swept-source optical coherence tomography angiography (SS-OCTA), slit-lamp, and fundus examinations.

Results: The study included 44 children (average age: 9.79 years; 56.82% male). RLRL therapy significantly increased subfoveal choroidal thickness (Baseline: 272.82 ± 64.01 μm; 1-month: 297.77 ± 72.94 μm; 3-month: 298.77 ± 77.17 μm, p = 0.001), reduced axial length (Baseline: 24.97 ± 1.47 mm; 3-month: 24.88 ± 1.38 mm, p = 0.002), and showed a marginal regression in spherical equivalent (p = 0.055). Significant elevations in choroidal vessel volume and thickness were noted, with positive correlations intensifying with distance from the fovea.

Conclusion: RLRL therapy shows promise in managing pediatric myopia by increasing choroidal vessel volume and thickness, potentially mitigating myopia progression.