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Currently, microbial infections have posed an arduous challenge to global public health, whereas the rise of antibiotic resistance is rendering traditional antibiotic therapies futile, prompting the development of new antimicrobial technologies. Photoactive nanomaterials have thus garnered a thriving interest for disinfection owing to their superior antibacterial efficaciousness, favorable biosafety, and rapidness and spatiotemporal precision in excreting bactericidal actions. The review summarizes recent advances and emerging trends in the design, nanoengineering, and bioapplications of photoactive antimicrobials. It commences by elaborating fundamental theories on bacterial resistance, and antibacterial mechanisms of nanomaterials and phototherapy. Subsequently, the regulation of the antibacterial effectiveness of photoactive nanomaterials is comprehensively discussed, centering on criteria and strategies for tuning photoabsorption spectra, photothermal conversion, and photocatalytic efficiency, alongside tactics for enabling synergistic therapies. This is followed by comparative analyses of techniques and modalities for synthesizing and engineering photoactive nanomaterials with diverse structures, forms, and functionalities. Thereafter, the state‐of‐the‐art applications of phototherapies across various medical sectors are portrayed, and key challenges and opportunities are finally discussed to spur future innovations and translation. This review is envisaged to provide useful guidance for devising and developing nanomaterials‐based photoresponsive antimicrobials with application‐specific materials properties and biological functions. [ABSTRACT FROM AUTHOR]

The application of transition metal complexes for antimicrobial photodynamic therapy (PDT) has emerged as an attractive alternative in mitigating a broad range of bacterial pathogens, including multidrug‐resistant pathogens. In view of their photostability, long excited‐state lifetimes, and tunable emission properties, transition metal complexes also contribute as bioimaging agents. In the present work, we designed mono and trinuclear cyclometalated iridium (III) complexes to explore their imaging application and antibacterial potential. For this, we used Methicillin‐resistant S. aureus (MRSA), the most prevalent of community‐associated (CA) multidrug‐resistant (MDR) bacteria (CA MDR) and Lactococcus lactis (L. lactis) as Gram‐positive while Campylobacter jejuni (C. jejuni) and E. coli as Gram‐negative bacteria. In addition to differential bioimaging of these bacteria, we assessed the antibacterial effects of both mono and trinuclear Ir(III) complexes under exposure to 427 nm LED light. The data presented herein strongly suggest better efficacy of trinuclear Ir(III) complex over the mononuclear complex in imparting photoinduced cell death of MRSA. Based on the safety profile of these complexes, we propose that trinuclear cyclometalated iridium(III) complex holds great promise for selective recognition and targeting MDR bacteria with minimal off‐target effect. [ABSTRACT FROM AUTHOR]

Nowadays, cancer has become the leading cause of death worldwide, driving the need for effective therapeutics to improve patient prognosis. Photodynamic therapy (PDT) has been widely applied as an antitumor modality, owing to its minimal invasiveness, localized tumor damage, and high safety profile. However, its efficacy is limited by poor stability of photosensitizers, inadequate tumor accumulation, and a complex tumor microenvironment. To overcome these challenges, extensive endeavors have been made to explore the co‐assembly of the widely used photosensitizer chlorin e6 (Ce6) with various functional small molecules to enhance pharmacodynamic activity. This review provides a comprehensive overview of current studies on Ce6‐based nanoparticles for effective PDT and precise delivery of functional molecules. The self‐assembly mechanism will be discussed in detail, with a focus on potential strategies for combinational therapy with PDT. [ABSTRACT FROM AUTHOR]

Rationally designed multiporphyrinic architectures for boosting photodynamic therapy (PDT) have attracted significant attentions recently years due to their great potential for light‐mediated generation of reactive oxygen species. However, there is still a gap between the structure design and their PDT performance for biomedical applications. This tutorial review provides a historical overview on (i) the basic concept of PDT for deeply understanding the porphyrin‐mediated PDT reactions, (ii) developing strategies for constructing porphyrinic architectures, like nanorings, boxes, metal‐organic frameworks (MOFs), covalent‐organic frameworks (COFs), vesicles, etc., where we classified into the following three categories: multiporphyrin arrays, porphyrinic frameworks, and others porphyrin assemblies, (iii) the various application scenarios for clinical cancer therapy and antibacterial infection. Also, the existing challenges and future perspectives on the innovation of porphyrinic architectures for clinical PDT applications are mentioned in the end section. Moreover, the porphyrinic nanomaterials with atomically precise architectures provide an ideal platform for investigating the relationship between structures and PDT outputs, design of personalized "all‐in‐one" theranostic agents, and the popularization and application in wider biomedical fields. [ABSTRACT FROM AUTHOR]

Minimally invasive esophagectomy has gradually been accepted as an active treatment option for surgery of esophageal cancer. However, there is no consensus about how to perform the procedures in the thoracic and abdominal phase including anastomosis in the neck (McKeown) or chest (Ivor Lewis), VATS, robotic‐assisted or reduced port approaches or various endoscopic abrasion techniques. Further studies to investigate the roles of these novel techniques are required to treat the various patient populations. [ABSTRACT FROM AUTHOR]

The development of simple, efficient, and biocompatible organic luminescent molecules is of great significance to the clinical transformation of biomaterials. In recent years, purely organic thermally activated delayed fluorescence (TADF) materials with an extremely small single‐triplet energy gap (ΔEST) have been considered as the most promising new‐generation electroluminescence emitters, which is an enormous breakthrough in organic optoelectronics. By merits of the unique photophysical properties, high structure flexibility, and reduced health risks, such metal‐free TADF luminophores have attracted tremendous attention in biomedical fields, including conventional fluorescence imaging, time‐resolved imaging and sensing, and photodynamic therapy. However, there is currently no systematic summary of the TADF materials for biomedical applications, which is presented in this review. Besides a brief introduction of the major developments of TADF material, the typical TADF mechanisms and fundamental principles on design strategies of TADF molecules and nanomaterials are subsequently described. Importantly, a specific emphasis is placed on the discussion of TADF materials for various biomedical applications. Finally, the authors make a forecast of the remaining challenges and future developments. This review provides insightful perspectives and clear prospects towards the rapid development of TADF materials in biomedicine, which will be highly valuable to exploit new luminescent materials. [ABSTRACT FROM AUTHOR]

Biofilms are a persistent issue in healthcare and industry. Once formed, the eradication of biofilms is challenging as the extracellular polymeric matrix provides protection against harsh environmental conditions and physically enhances resistance to antimicrobials. The fabrication of polymer brush coatings provides a versatile approach to modify the surface to resist the formation of biofilms. Herein, the authors report a facile synthetic route for the preparation of surface‐tethered polymeric brushes with antifouling and visible light activated bactericidal properties using surface‐initiated photoinduced electron transfer‐reversible addition‐fragmentation chain transfer polymerization (SI‐PET‐RAFT). Bactericidal property via the generation of singlet oxygen, which can be temporally and spatially controlled, is investigated against both Gram‐positive and Gram‐negative bacteria. In addition, the antibacterial properties of the surface can be recycled. This work paves the way for the preparation of polymer films that can resist and kill bacterial biofilms [ABSTRACT FROM AUTHOR]

Light‐responsive inorganic biomaterials are an emerging class of materials used for developing noninvasive, noncontact, precise, and controllable medical devices in a wide range of biomedical applications, including photothermal therapy, photodynamic therapy, drug delivery, and regenerative medicine. Herein, a range of biomaterials is discussed, including carbon‐based nanomaterials, gold nanoparticles, graphite carbon nitride, transition metal dichalcogenides, and up‐conversion nanoparticles that are used in the design of light‐responsive medical devices. The importance of these light‐responsive biomaterials is explored to design light‐guided nanovehicle, modulate cellular behavior, as well as regulate extracellular microenvironments. Additionally, future perspectives on the clinical use of light‐responsive biomaterials are highlighted. [ABSTRACT FROM AUTHOR]

The integration of diagnosis and therapy based on natural products has been receiving considerable attention in recent years because nature can contribute many fantastic functional molecules with good biocompatibility and low toxicity. Diagnostic and therapeutic agents combined with the technique of photodynamic therapy (PDT) and sonodynamic therapy (SDT) have been extensively developed thanks to the advantages of PDT and SDT, such as good selectivity, low toxicity, and noninvasive treatment for cancers and other diseases compared with traditional treatments. In this review, we summarize the recent advances in theranostic agents for natural products categorized as porphyrins, perylenequinone, curcumin, and others. Some representative examples of disease diagnosis in fluorescence/photoacoustic imaging and disease treatment in PDT/SDT were introduced. Potential limitations and future perspectives of these natural products for theranostic agents were also discussed. [ABSTRACT FROM AUTHOR]

Background: Although photodynamic therapy (PDT) has emerged as a potential alternative to conventional chemotherapy, the low reactive oxygen species (ROS) yield of the photosensitizer such as TiO2 nanoparticles has limited its application. In addition, it is difficult to achieve effective tumor treatment with a single tumor therapy. Methods: We used TiOx nanocomposite (YSA‐PEG‐TiOX) instead of TiO2 as a photosensitizer to solve the problem of insufficient ROS generation in PDT. Benefiting from the desired mesoporous structure of TiOx, Cantharidin (CTD), one of the active components of mylabris, is loaded into TiOx for targeted combination of chemotherapy and PDT. The cellular uptake in human non‐small cell lung carcinoma cell line (A549) and human normal breast cell line (MCF 10A) was evaluated by confocal microscopy. in vitro cytotoxicity was evaluated using Cell Counting Kit‐8 assay. The ROS was detected via a chemical probe DCFH‐DA and the photodynamic treatment effect of YSA‐PEG‐TiOx was further evaluated by a living‐dead staining. The cell apoptosis was detected by the flow cytometry. Results: Our findings showed that the modification of YSA peptide improved the cytotoxicity of YSA‐PEG‐TiOX/CTD to EphA2 overexpressing A549 non‐small cell lung cancer (NSCLC) than non‐YSA modified counterparts. In addition, TiOx generated adequate ROS under X‐ray irradiation to further kill cancer cells. Flow analysis results also proved the superiority of this combined treatment. Conclusions: YSA‐PEG‐TiOX nanoparticles could significantly increase ROS production under X‐ray exposure and provide a new drug delivery nanocarrier for CTD in combination with PDT to achieve effective NSCLC treatment. [ABSTRACT FROM AUTHOR]

The viable use of photodynamic therapy (PDT) in cancer therapy has never been fully realized because of its undesirable effects on healthy tissues. Herein we summarize some physicochemical factors that can make PDT a more viable and effective option to provide future oncological patients with better‐quality treatment options. These physicochemical factors include light sources, photosensitizer (PS) carriers, microwaves, electric fields, magnetic fields, and ultrasound. This Review is meant to provide current information pertaining to PDT use, including a discussion of in vitro and in vivo studies. Emphasis is placed on the physicochemical factors and their potential benefits in overcoming the difficulty in transitioning PDT into the medical field. Many advanced techniques, such as employing X‐rays as a light source, using nanoparticle‐loaded stem cells and bacteriophage bio‐nanowires as a photosensitizer carrier, as well as integration with immunotherapy, are among the future directions. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterization of two new meso‐ferrocenylporphyrins, with the ferrocenyl unit attached at the para position of a C6F4 group by a CN bond with NH(CH2)2NH (2a) and NH(CH2)4NH (2b) spacers. Compounds 2a and 2b were characterized through elemental analyses, electrospray ionization high‐resolution mass spectrometry, 1H NMR, UV–visible and fluorescence spectroscopies, electrochemistry and spectroelectrochemistry. The free base porphyrin 2 was included for comparison purposes. The binding ability of 2 and the porphyrin derivatives 2a and 2b with calf thymus DNA was determined using UV–visible and fluorescence spectroscopies. The results suggest that the interaction of these systems most probably occurs through π‐stacking by non‐classical modes involving the partial insertion of the C6F5 ring between adjacent base pairs on DNA and possible hydrogen interaction with the aliphatic NH(CH2)nNH (n = 2 or 4) groups with calf thymus DNA. Moreover, we also demonstrate that porphyrins generate singlet oxygen species and show good photostability after irradiation. [ABSTRACT FROM AUTHOR]

Ruthenium polypyridyl complexes have received widespread attention as potential chemotherapeutics in photodynamic therapy (PDT) and in photochemotherapy (PACT). Here, we investigate a series of sixteen ruthenium polypyridyl complexes with general formula [Ru(tpy)(N−N)(L)]+/2+ (tpy=2,2′:6′,2′′-terpyridine, N−N=bpy (2,2′-bipyridine), phen (1,10-phenanthroline), dpq (pyrazino[2,3-f][1,10]phenanthroline), dppz (dipyrido[3,2-a:2′,3′-c]phenazine, dppn (benzo[i]dipyrido[3,2-a:2′,3′-c]phenazine), pmip (2-(4-methylphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), pymi ((E)-N-phenyl-1-(pyridin-2-yl)methanimine), or azpy (2-(phenylazo)pyridine), L=Cl− or 2-(2-(2-(methylthio)ethoxy)ethoxy)ethyl-β-d-glucopyranoside) and their potential for either PDT or PACT. We demonstrate that although increased lipophilicity is generally related to increased uptake of these complexes, it does not necessarily lead to increased (photo)cytotoxicity. However, the non-toxic complexes are excellent candidates as PACT carriers. [ABSTRACT FROM AUTHOR]

Genetically encoded photosensitizers (PSs), e.g. ROS generating proteins, correspond to a novel class of PSs that are highly desirable for biological and medical applications since they can be used in combination with a variety of genetic engineering manipulations allowing for precise spatio-temporal control of ROS production within living cells and organisms. In contrast to the commonly used chemical PSs, they can be modified using genetic engineering approaches and targeted to particular cellular compartments and cell types. Mini Singlet Oxygen Generator (miniSOG), a small flavoprotein capable of singlet oxygen production upon blue light irradiation, was initially reported as a high contrast probe for correlative light electron microscopy (CLEM) without the need of exogenous ligands, probes or destructive permeabilizing detergents. Further miniSOG was successfully applied for chromophore-assisted light inactivation (CALI) of proteins, as well as for photo-induced cell ablation in tissue cultures and in Caenorhabditis elegans. Finally, a novel approach of immunophotosensitizing has been developed, exploiting the specificity of mini-antibodies or selective scaffold proteins and photo-induced cytotoxicity of miniSOG, which is particularly promising for selective non-invasive photodynamic therapy of cancer (PDT) due to the spatial selectivity and locality of destructive action compared to other methods of oncotherapy. [ABSTRACT FROM AUTHOR]

Highlights: [•] Unsaturated lipids protect gramicidin channels from photosensitized inactivation. [•] Photosensitizer binding to membrane is independent of lipid unsaturation. [•] Double bonds in lipids reduce gramicidin inactivation by tert-butyl hydroperoxide. [Copyright &y& Elsevier]

Photodynamic therapy (PDT) of cells is a new treatment modality involving selective delivery of a photosensitive dye into target cells, followed by visible light irradiation. PDT induces cell death by excessive ROS generation. The effects of multiple photosensitizers were owing to the difference in cell types involving sensitizer-specific protein changes linked to resistance. HSP27 is regulated in response to stress and is associated with apoptotic process. The effects of HSP27 on PDT resistance are controversial and unclear. The purpose of this study was to investigate the role of HSP27 down-regulation in the PDT-induced cells and HSP27 regulation in the resistance to PDT. KB cells transfected with HSP27 siRNA were exposed to hematoporphyrin (HP) followed by irradiation at 635 nm at an energy density of 4.5 mW/cm2. After irradiation, the effects on HSP27 down-regulation were assessed by MTT assay, flow cytometry, confocal analysis, Western blotting and caspase activity. The results of this study showed that down-regulation of HSP27 restored cell survival in HP-PDT-induced apoptotic KB cells. HSP27 down-regulation attenuated PDT-induced apoptosis through caspase-mediated pathway in KB cells. Also, HSP27 silencing regulated Bax, Bcl-2, and PARP protein expression in PDT-induced cells. Therefore, HSP27 down-regulation confers resistance to PDT through interruption of apoptotic protein activity in PDT-induced cell death. HSP27 might contribute to regulating PDT-induced apoptosis in PDT-resistant cells. [ABSTRACT FROM AUTHOR]

Acta Ophthalmol. 2010: 88: 660–668 Purpose: To report on the clinical course of pulsating polypoidal choroidal vasculopathy (PCV) treated with photodynamic therapy (PDT). Methods: A total of 63 eyes of 58 consecutive patients diagnosed with PCV, treated with PDT and followed up for at least 6 months were enrolled. Best-corrected visual acuity (BCVA), fluorescein angiography and high-speed indocyanine green angiography (ICGA) using confocal scanning laser ophthalmoscopy (HRA) were performed. Results: Of the 63 PCV eyes, 14 eyes (22.2%) of 14 patients were classified as having pulsating PCV. The mean age of pulsating PCV patients was 60.6 ± 7.0 years (48–69 years), which was younger than non-pulsating PCV patients (65.7 years, p = 0.035). The mean follow-up period was 23.9 ± 10.7 months, and PDT was administered 1.6 ± 0.9 times to pulsating PCV patients. The mean logMAR BCVAs were 0.85 ± 0.47 at presentation and 0.71 ± 0.52 at final examination. Extensive haemorrhagic events were more common in pulsating than in non-pulsating PCV patients (57.1% versus 26.5%, p = 0.032). However, the risk of haemorrhage within 3 months of PDT was similar for both pulsating PCV and the remaining patients (14.3% versus 20%, p = 0.723). Conclusion: Pulsating PCV showed distinctive features including a relatively younger patient age at presentation, and a haemorrhagic tendency (especially extensive). However, the use of PDT did not directly increase the risk of haemorrhage in pulsating PCV patients. [ABSTRACT FROM AUTHOR]

Background/purpose: Photodynamic therapy (PDT) is a non-invasive cancer therapy that has a strong antitumor effect with intravenous administration of Photofrin. However, Photofrin causes light hypersensitivity that impairs the quality of life (QOL) of patients, and thus an improved method of administration is needed. Here, we report the antitumor effect of local administration of Photofrin in combination with a vasodilator, lidocaine hydrochloride. Method: The antitumor effect was investigated in nude mice transplanted with HeLa cells. An incision was made near the tumor and Photofrin dissolved in lidocaine jelly was applied directly to the tumor. The tumor was irradiated at 100 J/cm2 with a yttrium aluminum garnet (YAG)-dye laser (630 nm) at 2 h after the direct application and the tumor volume was measured for 30 days after PDT to investigate the antitumor effect. In some mice, the tumor was excised 24 h after PDT and the depth of necrosis was measured in the excised specimen. Result: The tumor was mostly necrotized by PDT following direct application of 10 mg/ml Photofrin dissolved in lidocaine jelly and the effect was greater than with direct application of Photofrin alone. The increase in tumor volume observed in control mice was significantly inhibited in mice that received PDT after direct application of Photofrin in lidocaine jelly. Conclusion: PDT using direct application of Photofrin in lidocaine jelly has a strong antitumor effect in mice and this approach may avoid the adverse effects of systemic Photofrin administration. [ABSTRACT FROM AUTHOR]

Background: Treatment of non-melanoma skin cancers (NMSC) with topical photodynamic therapy (PDT) is a treatment of choice for many clinicians. The two most commonly used PDT photosensitizer precursors are 5-aminolevulinic acid (ALA) and methyl aminolevulinate (MAL). Current PDT treatment regimes advise longer (4–6 h) application times for ALA and shorter times (3 h) for MAL. Aims: To establish the time course characteristics of protoporphyrin IX (PpIX) fluorescence following the application of ALA and MAL in normal skin. Methods: A total of 17 healthy volunteers were recruited, and both ALA and MAL were applied to the inner forearm for varying times (1–6 h). PpIX fluorescence was detected using a non-invasive spectroscopy system. Results and conclusion: PpIX fluorescence (following the application of either ALA or MAL) is dependent on duration of application. Following the application of ALA for 1–3 h peak fluorescence was noted at 7 h. Longer duration times (4–6 h) resulted in sustained fluorescence, which peaked at 24 h. MAL-induced fluorescence peaked at 7 h and was significantly decreased by 24 h for all application times. ALA induced fluorescence was shown to be significantly greater than MAL. The findings from this study have shown that potentially it would be more beneficial to apply ALA for shorter periods of time and MAL for longer than current practice. [ABSTRACT FROM AUTHOR]

We present a review of six clinical studies investigating the use of photodynamic therapy (PDT) using porphyrin precursors for the treatment of Old World cutaneous leishmaniasis (CL). Thirty-nine patients with a total of 77 lesions received PDT using a range of treatment schedules following topical application of aminolevulinic acid (ALA) or methyl-aminolevulinate (MAL). The tissue response to PDT is accompanied by a mild burning sensation, erythema and reversible hypo- and hyperpigmentation. Few mechanistic studies have addressed the principles underlying the use of PDT for CL. All six reviewed papers suggest that PDT with porphyrin precursors is relatively effective in treating CL. Data are still limited, and PDT cannot at this point be recommended in routine clinical practice. The mechanism of action of this promising therapeutic modality needs to investigated further and additional controlled trials need to be performed. [ABSTRACT FROM AUTHOR]

Abstract: The photodynamic response of the anthraquinone anticancer drug aclarubicin (ACL) was investigated in vitro and compared with that of mitoxantrone (MTX). Cultured immortalized rodent B14 and NIH 3T3 cells were used in the experiments as a model for cells with neoplastic phenotype. Long-term cytotoxicity and inhibition of cell proliferation assayed by the clonal growth and MTT-tetrazolium methods were estimated to compare the efficacy of aclarubicin and mitoxantrone in photosensitizing cells and their death after non-thermal exposure to monochromatic laser light. Green He–Ne (543.5nm) or red semiconductor (670nm) low-power laser (LPL) irradiations were applied. Different dose-responses of both cell lines to aclarubicin and mitoxantrone were found so that the cytotoxicity of MTX was considerably greater than the cytotoxicity of ACL. Phototherapy response (P <0.0001) was observed only for B14 cells after sensitisation with aclarubicin. Under the same conditions no significant effect of red light irradiation (semiconductor 670nm laser) on survival of both cell lines treated with mitoxantrone was found. [Copyright &y& Elsevier]

Background/Purpose: Topical photodynamic therapy (PDT) is increasingly being used to treat skin cancers. Knowledge of the detailed characteristics of 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence in diseased and normal skin is incomplete. Understanding the characteristics of PpIX fluorescence in normal skin may facilitate optimization of PDT regimes while minimizing side effects in the surrounding normal skin. We investigated the characteristics of ALA-induced PpIX fluorescence in normal skin. Methods: ALA was applied to the arm, back and leg skin of 21 healthy volunteers for 1–6 h, and PpIX fluorescence was measured for up to 24 h after ALA application using a fluorescent spectrometer. The effect of tape stripping on fluorescence was also examined. Results: Considerable inter-subject variation was observed in the time to reach peak PpIX fluorescence. Intra-subject variation in the time to peak fluorescence was dependent on ALA application time. Six hours after ALA application, no significant difference was observed in the degree of fluorescence achieved irrespective of ALA application times ranging between 1 and 6 h. PpIX fluorescence was reduced on the leg and increased by tape stripping. Conclusions: Marked inter- and intra-subject variation in ALA-induced PpIX fluorescence occurs in normal human skin. ALA application time, body site and the state of the stratum corneum are all determinants of PpIX fluorescence within subjects and these factors need to be taken into account in optimization of PDT regimes. [ABSTRACT FROM AUTHOR]

Background: Photodynamic therapy (PDT) is useful for the treatment of epidermal neoplasia but may also have use in the treatment of inflammatory dermatoses. The purpose of this study was to evaluate the safety and efficacy of PDT in the treatment of acne on the face. Methods: Eight patients with mild-to-moderate acne vulgaris on the face were treated with one session of topical aminolevulinic acid (ALA)-PDT using a red light. Each patient's face was divided into two areas (right side and left side) for ALA-PDT and untreated control. Twenty percent topical ALA was applied with 4 h occlusion, and 18 J/cm2 red light (630±63 nm) was administered. Each patient's acne was visually assessed by a spot count of both inflamed and non-inflamed lesions at baseline and at 1, 3, and 6 months following PDT. Results: At 1, 3, and 6 months, the mean percentage reduction in inflamed lesions count was 27.6%, 37.9%, and 41.9%, respectively, in the ALA-PDT-treated area, whereas in the control area, it was 8.0%, 14.7%, and 15.4%, respectively, compared with the baseline. This showed a higher reduction of a spot count of inflamed lesions in the ALA-PDT-treated area, which was statistically significant ( P<0.05). There was a slightly higher reduction of a spot count of non-inflamed lesions in the ALA-PDT-treated area, which was statistically not significant ( P>0.05). The adverse effects were minimal. Conclusion: ALA-PDT with red light was found to be effective in the reduction of the number of inflamed lesions in patients with mild-to-moderate acne vulgaris, with no significant short-term adverse effects. [ABSTRACT FROM AUTHOR]

Abstract: Photodynamic treatment (PDT) employs a photosensitizer and the light-induced formation of reactive oxygen species – antagonized by cellular antioxidant systems – for the removal of harmful cells. This study addresses the effect of altered carbohydrate metabolism on the cellular antioxidant glutathione system, and the subsequent responses to PDT. It is shown that glucose-deprivation of 18 h prior to PDT causes a reduced level of intracellular glutathione and an increased cytotoxicity of PDT. These effects can be mimicked by inhibitors of glutathione synthesis (buthionine-sulfoximine) or its regeneration (1,3-bis-(2-chlorethyl)-1-nitrosourea). Inhibited glutathione metabolism shifts the apoptotic window to lower fluences, while glucose deprivation abolishes apoptosis as a result of ATP deficiency. Our results prove evidence for manipulation of the outcome of PDT through internal metabolic pathways. [Copyright &y& Elsevier]

A considerable amount of new information on putative pathogenetic mechanisms in age-related maculopathy and degeneration has emerged in recent years. This comprises experimental studies on retinal pigment epithelium (RPE) and rod photoreceptor ageing, lipofuscin accumulation, the roles of oxidative stress and free radical formation, as well as antioxidants and other defensive mechanisms operating against environmental factors and ageing. The current application of photodynamic therapy (PDT) using verteporfin marks a new era in the treatment of subfoveal classical choroidal neovascularization. Several new treatment modalities, such as transpupillary thermotherapy (TTT) and anti-vascular endothelial growth factor (VEGF) agents for inhibition of neovascularization, have emerged and are undergoing multicentre clinical trials. A period of dynamic development in this field has commenced. [ABSTRACT FROM AUTHOR]

Leishmaniasis is a widespread arthropod-borne protozoan zoonosis caused by more than 21 Leishmania species. Vectors are sandflies of different genera. The disease is classified into „Old World” versus „New World” leishmaniasis and further subclassified in cutaneous, mucocutaneous and visceral forms. Most therapeutic approaches are not evidence-based. We report a patient with facial cuta-neous Leishmania tropica infection which proved to be resistant to various therapeutic regimes. Excellent results were achieved with photody-namic therapy. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) has been used in the treatment of cancers and other benign diseases for several years in clinic. However, the hypoxia of tumors and the penetration limitation of excitation light to tissues can dramatically reduce the efficacy of PDT to cancers. To overcome these drawbacks, various assembled nanocarriers such as nanoparticles, nanocapsules, nanocrystals, and so on were introduced. The assembled nanocarriers have the ability of loading photosensitizers, delivering O2 into tumors, generating O2 in situ in tumors, as well as turning near‐infrared (NIR) light, X‐rays, and chemical energy into ultraviolet or visible light. Therefore, it is easy for the nanocarriers to improve the hypoxia microenvironment or increase the treatment depth of cancers, which will improve the efficiency of PDT to some degree. In recent years, a number of investigations were focused on these subjects. We will summarize the advances of nanocarriers in PDT, especially in O2 introduction PDT and deep PDT. The perspectives, challenges, and potential in translation of PDT will also be discussed. This article is categorized under:Therapeutic Approaches and Drug Discovery > Emerging TechnologiesBiology‐Inspired Nanomaterials > Lipid‐Based StructuresTherapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease [ABSTRACT FROM AUTHOR]

Leishmaniasis is a vector borne disease transmitted by phlebotomine sandflies. Cutaneous leishmaniasis (CL) predominantly causes skin ulcers but may disseminate. CL may present a therapeutic challenge. The present study reports the case of a 15-year old boy with CL consisting of a single, ulcer on the leg, resistant to pentavalent antimony, oral fluconazole and topical ketoconazole therapy. Repeated photodynamic therapy using aminolevulinic acid resulted in complete healing of the ulcer, suggesting utility of this approach in resistant cases of CL., (© 2019 Wiley Periodicals, Inc.)

Hidradenitis suppurativa (HS) and pilonidal cysts are chronic, inflammatory skin conditions involving apocrine gland-bearing skin. Treatment is limited and unsatisfactory. Photodynamic therapy (PDT) has been reported to be safe and effective in the treatment of several off-label skin conditions. We report the case of a 29-year-old man affected by HS and pilonidal cysts since the age of 21. In the past, the patient was treated with antibiotics, corticosteroids and retinoids, without significant clinical improvement. Treatment with methyl aminolaevulinate (MAL)-PDT was started. A topical MAL cream (Metvix®) was applied to the affected areas with an occlusive dressing for 3 h and irradiated with a red light source. Therapy was repeated every 15 days for a total of nine applications. The patient completed a 6-month follow-up and achieved an almost complete clinical remission of the skin lesions (80%) and complete resolution of the itching and discomfort. This is the first case of HS associated with pilonidal cysts treated with MAL-PDT. MAL-PDT was effective and well tolerated in our patient. The costs of this therapy represent an important limitation, taking into account the high number of sessions that were performed compared with non-melanoma skin cancers. [ABSTRACT FROM AUTHOR]