Photodynamic Therapy Group Research Articles

Application of phytochemicals in photodynamic therapy of cancer

SignificanceHerbal medicine is an important part of the health care system in many countries as they exhibit chemopreventive and chemotherapeutic effects. The combination of phytochemicals with Photodynamic therapy is a novel approach to enhancing therapeutic efficacy. ApproachWe studied the effect of various plant extracts, phytochemicals, photosensitizers and their combinations to induce cell death in the lung, breast, colon, cervical and skin cancer cells. The efficacy of the drug moieties was evaluated using viability, proliferation, and cytotoxicity studies. Detailed cell death mechanism was studied using protein expression profiling using immunofluorescence, flow cytometry, ELISA and western blotting. ResultsThe results revealed that PDT and combination therapy groups showed significant cell death in breast and lung cancer cells. Conjugation of photosensitizers with nanoparticles and phytochemicals enhanced the drug delivery and treatment outcome. ConclusionsCombination of PDT with other existing treatments or replacing the synthetic PSs with natural ones is a promising approach in the fight against cancer with improved specific cancer cell targeting.

Comparison of 5-ALA-PDT and LEEP of cervical squamous intraepithelial neoplasia (CIN2) with high-risk human papillomavirus infection in childbearing age women: A non-randomized controlled polit study

Background5-Aminolevulinic acid-mediated photodynamic therapy (5-ALA-PDT) is a possible minimally-invasive treatment for high-grade cervical intraepithelial neoplasia (HSIL). The present study was carried out to assess the effect of 5-ALA-PDT and loop electrosurgical excision procedure (LEEP) in cervical squamous intraepithelial neoplasia (CIN2) combined with high-risk human papillomavirus (HR-HPV) infection. MethodsIn this study, 190 patients with CIN2 and HR-HPV infection were finally included. They were divided into the LEEP Group (n = 116) and PDT Group (n = 74) according to gynecologist's recommendation and patient's willingness. All patients were followed up at 4–6 months and 12 months after treatment, including HPV testing, cytology, and colposcopy examination. Results(1) 4–6 months after treatment, the pathological regression rate was 97.30 % (72/74) in the PDT group and 98.28 % (114/116) in the LEEP group (P = 0.952). The HPV clearance rate was 81.08 % (60/74) in the PDT group and 80.17 % (93/116)in the LEEP group (P = 0.877). (2) 12 months after treatment, the pathological regression rate was 93.24 % (69/74) in the PDT group and 96.55 % (112/116) in the LEEP group (P = 0.486). The recurrence rate of CIN2 was 4.05 % (3/74) in the PDT group and 1.72 % (2/116) in the LEEP group (P = 0.608). The HPV clearance rate was 90.54 % (67/74) in the PDT group and 89.66 % (104/116)in the LEEP group (P = 0.843). The reinfection rate of HR-HPV was 5.41 % (4/74) in the PDT group and 1.72 % (2/116) in the LEEP group (P = 0.322). (3) The adverse reactions in the PDT Group were slightly lower than that in the LEEP Group (P = 0.4956), but the incidence of vaginal bleeding in the PDT group was lower than that in the LEEP group during follow-up. ConclusionsThe effectiveness of 5-ALA-PDT is similar to LEEP for CIN2 with less side effects. Therefore, 5-ALA-PDT, a non-invasive treatment, may be an effective method for CIN2 patients of childbearing age.

Comparison between three methods of diode laser 810 nm, photodynamic therapy with laser 660 nm, and hypochlorite solution for disinfection of pulp canal of primary teeth

Background: The presence of treatment-resistant microorganisms is known as the main cause of pulpectomy failure in the endodontic treatment of deciduous teeth. The usage of lasers can contribute to reducing these microorganisms. This study aimed to compare the effect of three disinfection methods for deciduous teeth canals using laser diode 810 nm, photodynamic therapy with laser 660 nm and methylene blue, and sodium hypochlorite. Materials and Methods: In this experimental study, 58 single-root deciduous teeth with no root resorption were investigated in four groups, including one control group of 10 and three intervention groups of 16. Preparation of the samples was done using manual files up to three numbers after the initial file. After sterilizing the samples in an autoclave, Enterococcus faecalis bacteria were cultured in the canals. In the first group, irrigating with hypochlorite 2.5% was done; in the second group, photodynamic therapy was performed using a laser diode and 0.1 mg/mL methylene solution; and in the third group, high-intensity laser 810 nm direct radiation was done into the canal. Next, samples were taken from all canals. The colony formation unit (CFU) of the bacteria was counted in the blood agar culture medium. The data were analyzed using Kruskal-Wallis and negative binomial regression test (α =0.05). Results: The mean CFU differed significantly between the four groups. The rate of incidence of E. faecalis colonies showed a reduction in all three intervention groups compared to the negative control. In the high-intensity laser 810 nm group, there was 68.4%; in the photodynamic therapy with diode 660 nm and methylene blue, there was 88%; and in the hypochlorite group, 98.3% reduction was observed compared to the negative control group. Conclusion: Based on the results of this study, to compare three disinfection methods of the deciduous teeth canals without preparation of canals, sodium hypochlorite had greater efficiency. All three groups of laser, photodynamic therapy, and sodium hypochlorite showed reductions of E. faecalis bacterial colony compared to the control group. The reductive effects of CFU were greater in the hypochlorite sodium group, followed by photodynamic and direct laser radiation groups.

The Effect of Photodynamic Therapy Using 5-Aminolevulinic Acid in Bone and Soft Tissue Sarcoma Cells.

5-Aminolevulinic acid (5-ALA) is a natural amino acid and a precursor of protoporphyrin IX (PpIX). Following light irradiation, the PpIX generates reactive oxygen species (ROS) in the presence of oxygen. Increased ROS levels can cause apoptotic cell death and necrosis of targeted cancer cells. This study examined whether photodynamic therapy using 5ALA (5-ALA PDT) could be used as a potential adjuvant therapy for bone and soft tissue sarcomas. The human osteosarcoma (143B), mouse osteosarcoma (LM8), human fibrosarcoma cell (HT1080) cell lines were used. In vitro, cultured cells were exposed to 5-ALA at various concentrations followed by strobe scope light irradiation for 10 min as 5-ALA PDT. Cell viability was then measured. In vivo, each tumor cell line was inoculated subcutaneously into the backs of mice. In the 5-ALA PDT group, 5-ALA (250 mg/kg) was administered intraperitoneally followed by light irradiation. Change in tumor volume by 5-ALA PDT were primarily evaluated. In vitro, treatment of sarcoma cells with 100 and 200 μg/ml 5-ALA PDT significantly inhibited cell proliferation at 24 and 48 h compared with the group treated with 0 and 10 μg/ml 5-ALA PDT. In vivo, in all cell lines, a significant inhibition of the tumor volume was observed in the 5-ALA-PDT group as compared to that in control, strobe scope light, and 5-ALA groups. 5-ALA PDT effectively inhibited proliferation of bone and soft tissue sarcoma cell lines. Further in vivo research using other subtypes of bone and soft tissue sarcoma is warranted to confirm the applicability in the clinical setting.

Enhancing the Antibacterial Effect of Erythrosine-Mediated Photodynamic Therapy with Ethylenediamine Tetraacetic Acid

This study evaluated the additive impact of ethylenediamine tetraacetic acid (EDTA) on erythrosine-mediated photodynamic therapy (PDT) against <i>Streptococcus mutans</i> (<i>S. mutans</i>) biofilm by measuring colony-forming units and applying confocal laser scanning microscopy. Fifty-six bovine incisors, free from dental caries or structural defects, were utilized in this study. Dentin specimens were created by cutting with a low-speed diamond disk under a continuous flow of water, resulting in dimensions of 6.0 mm × 3.0 mm × 2.0 mm. The specimens were categorized into 4 groups: Control, EDTA, PDT, and EDTA + PDT. <i>S. mutans</i> ATCC 25175 was employed to establish biofilm on the dentin specimens. A 17% EDTA solution was applied for 1 min. For PDT, erythrosine served as the photosensitizer. Finally, a light-emitting diode source (385 - 515 nm) was employed in this study. The PDT group exhibited a significantly lower bacterial count than both the control and EDTA groups (<i>p</i> < 0.001). The EDTA + PDT group demonstrated a significantly reduced bacterial count compared to the other 3 groups (<i>p</i> < 0.001). This study demonstrated that EDTA enhances the antimicrobial efficacy of PDT on S. mutans biofilm. Even at a low concentration of photosensitizer, the combination of EDTA and PDT yields a significant antibacterial effect.

Efficacy and influencing factors of CO2 laser, topical photodynamic therapy versus therapy combined with CO2 laser pretreatment for vaginal low-grade squamous intraepithelial lesions with high-risk HPV infection

BackgroundVaginal intraepithelial neoplasia (VaIN) is a group of diseases of squamous epithelial dysplasia and carcinoma in situ occurring in the vagina, which is associated with high-risk human papillomavirus (HR-HPV) infection. ObjectivesTo evaluate the efficacy and safety of Carbon dioxide (CO2) laser, 5-aminolevulinic acid photodynamic therapy (PDT) and PDT combined with CO2 laser pretreatment for VaIN1 with HR-HPV infection, and analyze the factors affecting the clearance of HR-HPV. MethodsPatients with HR-HPV infection and pathological diagnosis of VaIN1 and received laser or PDT or PDT combined with laser pretreatment were recruited. A total of 45 patients received one to three times CO2 laser (laser Group), 15 patients received three times PDT (PDT Group) and 15 patients received CO2 laser once and PDT three times (laser + PDT Group). HPV testing, cytology and colposcopy examinations at 3–6 months and 9–12 months after treatment were analyzed to assess the outcomes of the treatment. Results: There was no significant difference in regression rate of VaIN1 among the laser Group, the PDT Group and the laser + PDT Group (3–6 month follow-up: 57.78% vs 73.3% vs 80 %, 9–12 month follow-up: 68.89% vs 80% vs 86.67 %, P>0.05). HR-HPV remission rates were also similar in the three groups (3–6 month follow-up: 26.67% vs 46.67% vs 46.67 %, 9–12 month follow-up: 40 % in all groups, P>0.05). Compared to HR-HPV negative group, patients in the HR-HPV positive group were older and had more pregnancies. Menopause and multiple vaginal lesions were more common in the HR-HPV positive group. Adverse reactions were mild in the PDT Group. The laser Group and the laser + PDT Group had more adverse effects, such as increased vaginal secretion, vaginal bleeding, scarring and local pain. ConclusionFor patients with VaIN1 at risk of progression, ALA-PDT presents itself as a viable choice for those who are well-informed and can consent to its costs and benefits. The addition of CO2 laser pretreatment may not increase the benefit of ALA-PDT treatment of VaIN1. Older age, menopause, more times of pregnancies, and multiple vaginal lesions might affect HR-HPV regression.

Photodynamic therapy of cationic and anionic BSA-curcumin nanoparticles on amastigotes of Leishmania braziliensis and Leishmania major and Leishmania amazonensis

Cutaneous leishmaniasis is a neglected disease prevalent in tropical countries, and conventional treatment can cause several serious side effects. Photodynamic therapy (PDT) can be considered a promising treatment alternative, as it is non-invasive therapy that has no side effects and uses accessible and low-cost substances, such as curcumin. This study evaluated the PDT response with cationic and anionic BSA nanoparticles encapsulated with curcumin in macrophages infected with L. braziliensis, L. major, and L. amazonensis. The nanoparticle system was characterized using a steady-state technique, scanning electron microscopy (SEM) study, and its biological activity was evaluated using macrophage cell lines infected with different Leishmania species. All spectroscopy measurements demonstrated that BSA curcumin (BSACur) has good photophysical properties, and confocal microscopy shows that macrophages and protozoa internalized the nanoparticles. The viability test demonstrated that at low concentrations, such as 0.1, 0.7, and 1.0 µmol. L−1, there was a decrease in cell viability after PDT application. Furthermore, a decrease in the number of parasites recovered was observed in the PDT groups. The results allowed us to conclude that curcumin loaded into BSA nanoparticles may have potential application in drug delivery systems for PDT protocols, demonstrating reduced cell viability at lower concentrations than free curcumin.

A prospective, split-face, randomized controlled trial of intense pulsed light-photodynamic therapy for seborrhea

BackgroundSeborrhea poses a common cosmetic concern in adolescents and young adults, often accompanied by enlarged pores, and contributing to various skin conditions, including acne vulgaris and seborrheic dermatitis. At present, there is a lack of effective treatment for this problem, and the potential of photodynamic therapy (PDT) in reducing sebum remains inconclusive. ObjectiveThis exploratory, prospective, single-center, double-blinded, randomized split-face controlled trial aimed to compare the efficacy and safety of intense pulsed light-photodynamic therapy (IPL-PDT) versus IPL therapy for seborrhea. MethodsParticipants with seborrhea underwent 3 times of IPL treatment (590 nm, 15–17 J/cm2 based on patient's tolerance) for one hemifacial part and IPL-PDT treatment for the other. Follow-up assessment was conducted up to 8 weeks after the final treatment. ResultsCompared with single IPL treatment, IPL-PDT can significantly inhibit sebum secretion and decrease pore size. PDT group exhibited no additional damage to the skin barrier, with even lower transepidermal water loss (TEWL). Additionally, the PDT group showed superior improvement in scores of porphyrins, red areas, and ultraviolet (UV) spots. Both groups experienced only mild topical adverse effects, well tolerated by the participants. ConclusionIPL-PDT is a more effective method than IPL in the treatment of seborrhea, as well as on the improvement of the skin barrier function.

Intravitreal anti-vascular endothelial growth factor and combined photodynamic therapy for pachychoroid neovasculopathy: long-term treatment outcomes

PurposeTo examine the long-term visual outcomes after initial treatment with combined photodynamic therapy (PDT) or aflibercept treat-and-extend (TAE) monotherapy in patients with pachychoroid neovasculopathy (PNV).MethodsPatients diagnosed with PNV, initially treated with PDT combined with anti-vascular endothelial growth factor (VEGF) or intravitreal aflibercept (IVA) monotherapy in the TAE protocol and followed up for at least 6 months, were included in the study. Medical records were retrospectively reviewed. Survival analysis was performed, in which deterioration in logMAR visual acuity by 0.1 or 0.3 is defined as “death.” The annual number of treatments was also analyzed. Sub-analysis was performed on 33 patients diagnosed with PNV without polypoidal lesions.ResultsThis study included 46 patients (23 in the initial combined PDT group and 23 in the IVA TAE group). Mean age, sex, mean baseline logMAR visual acuity, or duration of observation (3.6 ± 3.2 years vs. 3.1 ± 1.9 years) in both groups were comparable. As for visual outcome, no significant differences were found in survival analysis based on worsening of 0.1 or 0.3 logMAR (3-year survival; 26% vs. 26%, 91% vs. 90%, respectively). Meanwhile, the additional number of anti-VEGF injections per year was significantly lower in the initial combined PDT group than in the IVA TAE group (1.0 ± 1.3 vs. 4.1 ± 1.5, p < 0.0001). No significant differences were found in the number of additional PDTs per year (0.07 ± 0.20 vs. 0.02 ± 0.09, p = 0.27). Similar results were found in a sub-analysis of 33 patients without polyps.ConclusionIn the treatment of PNV, regardless of the presence of polyps, the long-term visual outcomes were similar between the initial combined PDT and IVA TAE monotherapy. However, the annual number of anti-VEGF injections was lower in the initial combined PDT group than in the aflibercept TAE group, whereas that of PDT was comparable.

Nano‐Mediated PDT as a Multifunctional Immunomodulatory Agent in the Intricate Milieu of Melanoma

AbstractThe complexity of the tumor microenvironment (TME) and nutrient competition represent the main causes of therapy resistance in cancers, including malignant melanoma (MM). Photodynamic therapy (PDT), through a cascade of events including its ability to induce significant immune responses, causes tumor eradication. However, the high pigmentation level of melanoma, lack of adequate accumulation of photosensitizers (PSs) in the target tissue as well as their nonspecific toxicity represent three main obstacles to obtaining satisfactory responses in melanoma. To prevail over these challenges, this study employs a depigmentation strategy followed by a nano‐mediated topical application of PDT using a chlorophyllin derivative as PS, focusing on the evaluation of the immunomodulatory and metabolic regulatory axes of PDT in melanoma. Photo‐immunomodulation is assessed in a melanoma mouse model using a nanocarrier system of the PS. Markers of the immunosuppressive microenvironment and T cell exhaustion, as independent immune hallmarks, are quantified. The histopathology of the spleen and skin/tumor is evaluated. The amino acid profile is quantified from normal skin or tumor biopsies using UHPLC‐MS/MS. Around 80% of the 300 nm transethosomal ferrous chlorophyllin (fC‐TEs) are retained in the tumor over 24 h upon topical application. Arbutin 2% gel not only decreased the melanin content of tumors but also regulated the expression of interleukin 12 (IL‐12), IL‐10, transforming growth factor beta (TGF‐β), and tumor necrosis factor‐alpha (TNF‐α). Additionally, the nano‐mediated PDT strategy decreased the expression of programmed cell death protein 1 (PD‐1) and its ligand 1 (PD‐L1) and reduces the activity of arginase 1 (Arg1) through an upregulation of miRNA155. A mild recruitment of megakaryocytes (MKs) is observed in the spleen of the PDT group. This special localization of MKs depicts effector immune properties. Lastly, the combination of PDT and arbutin restores the normal tissue levels of arginine (Arg), and glutamine (Gln) and lavished those of tryptophan (Trp). Nano‐mediated PDT represents a novel immunotherapeutic approach in melanoma by a triple modulation of the immune suppressive TME, immune checkpoint signaling, and reprogrammed tumor metabolism.

Comparative efficacy of brolucizumab, half-dose photodynamic therapy, and aflibercept in managing chronic central serous chorioretinopathy.

To compare the efficacy of brolucizumab, half-dose PDT, and aflibercept in treating chronic central serous chorioretinopathy (CSC). A retrospective cohort study with chronic CSC patients who underwent intravitreal injection of one shot of brolucizumab or aflibercept in the first 3 months, followed by pro re nata regimens or a single session of half-dose PDT, was retrospectively reviewed. The primary outcome measure was the proportion of eyes that achieved complete absorption of retinal fluid without requiring any rescue treatment. Secondary outcomes included changes in best-corrected visual acuity (BCVA), central retinal thickness (CRT), and central choroidal thickness (CCT). A total of 54 consecutive patients were included in this study with 18 patients in each group. At months 1 and 2, the brolucizumab group exhibited the highest rate of complete retinal fluid resolution (61% and 77%), followed by the half-dose PDT group (56% and 72%), and lowest in the aflibercept group (28% and 33%), with statistically significant differences noted at month 2 (P = 0.012). The brolucizumab group also demonstrated the most significant reduction in CCT at months 1 and 2 among the three groups (P = 0.007 and 0.001). Recurrence of retinal fluid in the brolucizumab groups was predominantly observed at month 3. Conversely, the half-dose PDT group exhibited the most favorable anatomical results starting from month 3. Notably, mild vitritis was observed in one case from the brolucizumab group. Single injection of brolucizumab demonstrates trends of faster regression of persistent residual retinal fluid, greater CCT and CRT decline, and matched BCVA compared to half-dose PDT in the short term.

Photoinactivation Effects of Curcumin, Nano-curcumin, and Erythrosine on Planktonic and Biofilm Cultures of Streptococcus mutans.

Introduction: This in vitro study was conducted to assess the phototoxic effects of curcumin, nano-curcumin, and erythrosine on the viability of Streptococcus mutans (S. mutans) in suspension and biofilm forms. Methods: Various concentrations of curcumin (1.5 g/L, 3 g/L), nano-curcumin (3 g/L), and erythrosine (100 μM/L, 250 μM/L) were examined for their impact on planktonic and biofilm cultures of S. mutans, either individually or in conjunction with light irradiation (photodynamic therapy or PDT). A blue light-emitting diode (LED) with a central wavelength of 450 nm served as the light source. The results were compared to 0.12% chlorhexidine digluconate (CHX) as the positive control, and a solution containing neither a photosensitizer (PS) nor a light source as the negative control group. The dependent variable was the number of viable microorganisms per experiment (CFU/mL). Results: Antimicrobial PDT caused a significant reduction in the viability of S. mutans in both planktonic and biofilm forms, compared to the negative control group (P<0.05). The highest cell killing was observed in PDT groups with curcumin 3 g/L or erythrosine 250 μmol/L, although the difference with PDT groups using curcumin 1.5 g/L or erythrosine 100 μmol/L was not significant (P>0.05). Antimicrobial treatments were more effective against planktonic S. mutans than the biofilm form. Conclusion: PDT with either curcumin 1.5 g/L or erythrosine 100 μmol/L may be suggested as an alternative to CHX to inactivate the bacteria in dental plaque or deep cavities. Nano-curcumin, at the selected concentration, exhibited lower efficacy in killing S. mutans compared to Curcumin or erythrosine.

Exploration of new models for primary dysmenorrhea treatment: low-power visible-light-activated photodynamic therapy and oral contraceptives.

Primary dysmenorrhea (PD) is one of the most common reasons that affect the life quality of women during childbearing age. This research aims to explore the efficacy and curative effect characteristics of oral contraceptives and low-power visible-light-activated photodynamic therapy (PDT). Besides investigating the possible mechanism of PDT, we expected to find a treatment model with better efficacy and fewer side effects. It was a multicenter, randomized, parallel-controlled study. Eligible participants were randomly assigned to three groups: placebo group, oral contraceptive (Marvelon) group, and the PDT group. They were treated continuously for three menstrual cycles and followed up for two cycles after treatment. The scores of the visual analog scale (VAS) and the concentration of pain-related small molecules in blood before and after treatment were recorded in each group, which can evaluate the therapeutic characteristics of different treatments. Both Marvelon and PDT were effective. The effect of Marvelon appears quickly which can significantly relieve symptoms at the beginning, while PDT shows a relatively slow role. There was no significant difference in the final efficacy two cycles after treatment. The therapeutic effect was achieved by reducing the concentrations of prostaglandin 2 (PGE2) and endothelin (ET) in the blood. Marvelon and PDT are effective methods for the treatment of PD. The long-term efficacy of the two is similar, while the therapeutic characteristics and the side effects are different. Patients can choose the suitable way according to their individual needs.

Evaluation of the photodynamic effect on the state of microcirculation and oxygenation in periodontal tissues in the treatment of chronic generalized periodontitis

Increasing the effectiveness of treatment of chronic generalized periodontitis using PDT based on clinical and functional substantiation of the effects of a photosensitizer. A clinical and functional study and treatment of moderate chronic generalized periodontitis was carried out in 62 people (26 men and 36 women) aged from 35 to 55 years without a somatic model with an orthognathic occlusion diagnosed according to ICD-10 - K05.3. Of these, 2 groups were divided depending on the type of treatment: Group 1 (main) - patients with moderate chronic generalized periodontitis - 32 people. (17 men and 15 women, average age of the group - 43.2±2.2 years); Group 2 (control) - patients with moderate chronic generalized periodontitis - 30 people. (14 men and 16 women, average age of the group - 44.0±3.3 years). Complex treatment consisted of sanitation of the mouth, removal of dental plaque and curettage of periodontal pockets in group 1, followed by PDT with Revixan gel using a special wired aligner REVIXAN DENTAL LED (16 r). The clinical condition of the periodontium was assessed using the Greene Vermillion Hygienic Index (OHI-S), the Mühlleman Bleeding Index (SBI) modified by Cowell, and the periodontal index PI. To study the state of microcirculation in the gum tissue, the laser Doppler flowmetry (LDF) method was used using the LAKK-M device (NPP «Lazma», Russia). The state of microcirculation was assessed by the microcirculation index (M), which characterizes the level of tissue blood flow; parameter - «σ», which determines the fluctuation of the erythrocyte flow. According to Wavelet analysis of LDF-grams, the shunt index (SH) of blood flow was determined. In the «LDF + spectrometry» mode, oxygenation in periodontal tissues was studied using optical tissue oximetry (OTO), based on the results of which the perfusion saturation index (Sm) and the specific oxygen consumption index (U, %) were determined. According to LDF data, after PDT (group 1), normalization of clinical indices and the level of microcirculation in periodontal tissues was established, which was accompanied by an increase in the level of blood flow (M) and its activity (σ), which persisted after 3 and 6 months. after PDT. The perfusion saturation index (Sm) and specific oxygen consumption (U) increased more significantly after PDT, which persisted after 3 and 6 months. In the control group, the dynamics of indicators was less pronounced. The use of PDT with Revixan gel normalizes the clinical condition of the periodontium, indicators of microhemodynamics and oxygen metabolism.

Nano-emodin mediated photodynamic therapy for wound healing of donor site after free gingival graft: A parallel clinical trial

AimThis study aimed to evaluate the effectiveness of nano-emodin (n-Emo) mediated photodynamic therapy (PDT) as an adjunctive therapy to conventional wound care in patients undergoing free gingival graft (FGG) treatment. The study employed a single-center, parallel, two-blind, randomized, controlled trial design. Method and materialA total of 53 patients requiring FGG treatment were randomly assigned to one of three groups: the n-Emo mediated PDT group, the n-Emo gel group, and the control group. The n-Emo mediated PDT group received n-Emo gel on donor site followed by LED (450 nm, 1000 ± 1400 mW/cm2, 60–80 J/cm2, 60 s), the n-Emo gel group received only n-Emo gel on donor site, and the control group received a placebo gel on donor site. All groups received treatment immediately and 48 h after FGG surgery. Wound healing was assessed based on wound area, bleeding, color match, and epithelialization. Postoperative pain perception was evaluated using a Visual Analogue Scale (VAS), and the number of non-steroidal anti-inflammatory drug (NSAID) intakes was recorded. ResultsThe results showed that all groups demonstrated significant improvement in wound healing by day 28, with the n-Emo mediated PDT exhibiting significantly better healing on the 14th, 21st, and 28th day compared to the control group. Additionally, on the 28th day, the n-Emo mediated PDT showed significantly better healing than the n-Emo gel group. The n-Emo mediated PDT also had significantly lower pain scores than the control group. There were no significant differences in the number of NSAID intakes, bleeding, or color match among the groups, but all groups showed improved color match during follow-up. By the third week, all groups had fully epithelialized without significant differences, and no secondary bleeding incidents were reported. ConclusionThe study concludes that n-Emo mediated PDT is an effective adjunctive therapy to conventional wound care for managing complication after surgery at donor site after FGG surgery.

A randomized non-inferiority trial of 577nm subthreshold micropulse laser versus half-dose photodynamic therapy for acute central serous chorioretinopathy

PurposeTo compare the effectiveness of 577nm subthreshold micropulse laser (SML) with half-dose photodynamic therapy (Hd-PDT) for acute central serous chorioretinopathy (CSC). MethodA non-inferiority clinical trial was performed with a non-inferiority margin of eight letters. Sixty-eight eyes of 68 patients with acute CSC were randomized to the Hd-PDT group or 577 nm SML group. Best-corrected visual acuity (BCVA ), the subretinal fluid (SRF), and the central foveal thickness (CFT) were evaluated at 6 months. ResultsThe visual acuity significantly improved from 70.38 ± 10.37 at baseline to 83.24 ± 3.03 at 6 months after treatment in the SML group (P < 0.001), from 71.09 ± 10.50 to 84.35 ± 2.09 in the PDT group (P < 0.001). SML was non-inferior to the PDT (mean difference: -0.41, 95% CI: -5.51 – 4.68, P = 0.0021). At the endpoint, CFT was significantly reduced in the two groups, but no statistical difference (P = 0.7694). The complete resolution of SRF reached 82.35% (28/34) in the SML group and 91.18% (31/34) in the PDT group, respectively,but no statistical difference (P = 0.3724). ConclusionsSML was non-inferiority to half-dose PDT in improving the visual acuity for CSC, and it is a viable alternative, especially when the verteporfin in PDT is unavailable.

Selenium enhances photodynamic therapy of C-phycocyanin against lung cancer via dual regulation of cytotoxicity and antioxidant activity.

As a natural photosensitizer, phycocyanin (PC) has high efficiency and uses low-intensity irradiation. To enhance the photodynamic therapy (PDT) of PC, we extract selenium-enriched phycocyanin (Se-PC) from Se-enriched Spirulina platensis and examine the synergistic effect of PC combined with selenium against lung tumors. In vitro experiments reveal that Se-PC PDT more efficiently reduce the survival rate of mouse lung cancer cells (LLC cell line) than PC PDT treatment by increasing the level of ROS and decreasing the level of GPx4, which is confirmed by the Chou-Talalay assay. In vivo imaging system analysis reveal that tumor volume is more markedly decreased in both the Se-PC PDT and PC PDT plus Na 2SeO 3 groups than in the PC PDT group, with inhibition rates reaching 90.4%, 68.3% and 53.1%, respectively, after irradiation with 100 J/cm 2 laser light at 630 nm. In normal tissues, Se-PC promotes the synthesis of antioxidant enzymes and the immune response by the IL-6/TNF-α pathway against tumor proliferation and metastasis. Using Se-PC as a photosensitizer in tumors, apoptosis and pyroptosis are the primary types of cell death switched by Caspases-1/3/9, which is confirmed by TEM. Based on the transcriptome analysis, Se-PC PDT treatment inhibits angiogenesis, regulates inflammation by the HIF-1, NF-κB and TGF-β signaling pathways and dilutes tumor metabolism by reducing the synthesis of glucose transporters and transferrin. Compared to PC PDT, Se-PC increases the expression levels of some chemokines in the tumor niche, which recruits inflammatory cells to enhance the immune response. Our study may provide evidence for Se-PC as an effective photosensitizer to treat lung cancer.

Choroidal Vessel and Stromal Volumetric Analysis After Photodynamic Therapy or Focal Laser for Central Serous Chorioretinopathy.

To utilize volumetric analysis to quantify volumetric changes in choroidal vessels and stroma after photodynamic therapy (PDT) and focal laser photocoagulation (PC) for central serous chorioretinopathy (CSCR). This retrospective, comparative study included 58 eyes (58 patients) with CSCR (PC, 33 eyes; PDT, 25 eyes) followed up with swept-source optical coherence tomography at 3 months after treatment. Three-dimensional (3D) choroidal vessel and stromal volumes in each area of the central 1.5-mm-diameter circle, the torus-shaped area with 6-mm-diameter circle excluding the area of the central 1.5-mm-diameter circle, and the treated area of the Early Treatment Diabetic Retinopathy Study (ETDRS) grid centered at the fovea were analyzed using a deep learning-based method. Changes in volume at baseline and 1 and 3 months after treatment were compared. The mean patient age was 49.3 ± 10.5 years. In the central 1.5-mm-diameter circle, the mean vessel and stromal volume rates significantly decreased after the treatment in both the PDT and PC groups (P = 0.00029 and P = 0.0014, respectively), and significant differences between the PDT and PC groups of continuous variables within times were observed in both volumes (P = 0.024 and P = 0.037, respectively). In the torus-shaped area and treated area, the PDT and PC groups both showed similar decreases in vessel and stromal volume over time. In the 3D optical coherence tomography volumetric analysis, both PDT and focal PC reduced choroid vessel volume in eyes with CSCR. This new finding is useful in elucidating the pathogenesis and healing mechanisms of CSCR.

Indocyanine green based photodynamic therapy for keloids: Fundamental investigation and clinical improvement

BackgroundKeloid, a prevalent pathological skin lesion, presents significant challenges in terms of treatment efficacy. Photodynamic therapy (PDT), an increasingly popular adjuvant treatment, has shown significant potential in the management of various disorders, including cancer. However, the therapeutic potential of indocyanine green-mediated photodynamic therapy (ICG-PDT) for keloids has not yet been demonstrated. MethodsIn this study, we divided the experimental groups into control group, Photothermal Therapy group, Photodynamic Therapy group, and Combined Therapy group. The in vitro investigation aimed to optimize the clinical application of PDT for keloid treatment by elucidating its underlying mechanism. Subsequently, on this basis, we endeavored to manage a clinical case of keloid by employing surgical intervention in conjunction with modified ICG-PDT. ResultsOur investigation revealed an unexpected outcome that ICG-PDT maximally inhibited the cellular activity and migration of keloid fibroblasts only when photodynamic mechanism took effect. Additionally, the induction of autophagy and apoptosis, as well as the inhibition of collagen synthesis, were particularly evident in this experimental group. Furthermore, the above therapeutic effect could be achieved at remarkably low drug concentrations. Building upon the aforementioned experimental findings, we successfully optimized the treatment modality for the latest case and obtained a more favorable treatment outcome. ConclusionsThis study investigated the mechanism of ICG-PDT treatment and optimized the in vivo treatment regimen, demonstrating the significant therapeutic potential of ICG-PDT treatment in clinical keloid treatment.

Comparing Half-Dose Photodynamic Therapy with Subthreshold Micropulse Laser for the Treatment of Central Serous Chorioretinopathy

To compare the anatomic and functional outcomes of half-dose photodynamic therapy (PDT) and yellow 577-nm subthreshold micropulse laser (SMLT) in treating patients with chronic central serous chorioretinopathy (CSCR). Prospective, double-masked, randomized, controlled clinical trial. Patients with chronic CSCR confirmed by clinical features and multimodal imaging. Eligible patients were randomized (1:1) to receive half-dose PDT or SMLT. The same treatment was repeated if persistent subretinal fluid (SRF) was observed. Treatment responses were evaluated 1 month after treatment and every 3 months until the end point at 12 months. The primary outcome measure was the complete resolution of SRF on OCT scan at month 12. Secondary outcomes included the changes in best-corrected visual acuity (BCVA), central macular thickness (CMT) as measured by OCT, retinal sensitivity as measured by microperimetry, and vision-related quality of life using the National Eye Institute 25-Item Visual Function Questionnaire. Between April 2017 and October 2020, 68 patients were recruited. At 1 month after treatment, SRF resolved in 8 (24.2%) of 33 patients receiving SMLT and in 20 (58.8%) of 34 patients receiving half-dose PDT. This increased to 23 (82.1%) of 28 patients in the SMLT group and 30 (90.9%) of 33 patients in the half-dose PDT group at 12 months of follow-up. Kaplan-Meier survival curves showed significantly faster resolution of SRF in the half-dose PDT group than the SMLT group (P= 0.016). Both groups showed significant improvement in BCVA (-0.12 ± 0.21, P= 0.005 for SMLT;-0.13 ± 0.12, P < 0.001 for half-dose PDT), CMT (-154.2 ± 105.6, P < 0.001 for SMLT;-140.8 ± 94.0, P < 0.001 for half-dose PDT), and retinal sensitivity (5.70 ± 5.02, P < 0.001 for SMLT; 6.05 ± 3.83, P < 0.001 for half-dose PDT) at 12 months compared with baseline. There was no significant difference between the 2 treatment groups at each time point in all investigations except BCVA at 3 months (P= 0.03). When comparing half-dose PDT to subthreshold SMLT, this study has shown both treatments to be viable options, with half-dose PDT achieving faster anatomic success and functional improvement. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.