Energy-Based Devices for the Treatment of Cutaneous Verrucae: A Systematic Review.

BACKGROUND: Warts are one of the most common benign neoplasms caused by human papillomavirus infection and often pose a therapeutic challenge. OBJECTIVE: To summarize the current evidence on the safety and efficacy of laser and energy-based devices for the treatment of cutaneous verrucae. METHODS: A comprehensive systematic review of the literature on laser and energy-based devices for the treatment of cutaneous verrucae was performed. RESULTS: A total of 904 unique studies were identified, of which 109 were included in this review. The most commonly used lasers as a single treatment modality for verrucae included the long-pulsed Nd:Yag (n = 20) and pulsed dye (n = 18) lasers. Other modalities included the CO2 ablative laser (n = 10), photodynamic therapy (n = 11), local hyperthermia (n = 11), microwave therapy (n = 2), and nanopulse stimulation (n = 1). Other studies combined energy-based modalities with additional treatments, such as retinoids, imiquimod, and intralesional bleomycin. Overall, such devices were generally well-tolerated, with only a mild side effect profile. CONCLUSION: Overall, the use of laser and energy-based devices is a safe and well-tolerated option for cutaneous verrucae that is relatively less invasive than surgical interventions. Future studies using more consistent outcome assessment tools will be valuable to help clinicians develop device-specific protocols and treatment regimens to ensure replicable and effective outcomes.

Ação antifúngica e potencial antibiofilme de diferentes terapias alternativas frente a leveduras do gênero candida / Antifungal action and antibiofilm potential of different alternative therapies against yeasts of the genus candida

As candidoses usualmente são tratadas com antifúngicos. No entanto, o efeito desses fármacos é usualmente comprometido pela resistência microbiana e pelos efeitos adversos ocasionados. Nesse sentido, o aumento da prevalência e a complexidade de microrganismos multirresistentes a antimicrobianos têm incitado a busca por terapias complementares e alternativas capazes de atuar efetivamente frente à resistência emergente aos medicamentos. Diante disso, o objetivo desse trabalho foi avaliar comparativamente a ação antimicrobiana e o potencial antibiofilme, in vitro, entre a terapia fotodinâmica antimirobiana (TFDA) com azul de metileno, a fitoterapia, utilizando o extrato hidroetanólico de Spondias mombin L (EHSM), e o probiótico Lactobacillus rhamnosus (PLR) no controle de leveduras do gênero Candida, sendo elas: Candida albicans, Candida tropicalis e Candida parapsilosis. Trata-se de um estudo experimental, in vitro, analítico e quantitativo, em que foram investigadas, em triplicata, a atividade inibidora do crescimento microbiano e a atividade antibiofilme das seguintes terapias alternativas: TFDA, EHSM e PLR, utilizando como controle positivo a Nistatina 100.000UI/mL. Quanto à análise estatística, além da interpretação descritiva, foi aplicado o teste Two-Way ANOVA e o Teste de Tukey. Dessa forma, observou-se que todas as terapias testadas exibiram atividades antifúngica e antibiofilme. Todavia, quando comparadas tais atividades entre elas e ainda com a Nistatina, verificou-se que: a TFDA apresentou a maior atividade inibitória de crescimento microbiano (p<0,05), semelhante a Nistatina, seguida pelo EHSM, exibindo o PLR a menor atividade antifúngica e a TFDA juntamente com o EHSM representaram as terapias com maior atividade antibiofilme (p<0,0001), atuando ambas de forma semelhante a Nistatina. Nesse sentido, foi possível concluir que todas as terapias estudadas possuem atividades antifúngica e antibiofilme frente às cepas do gênero Candida testadas, com destaque para a atividade inibidora de crescimento microbiano da TFDA e a atividade antibiofilme da TFDA e do EHSM, sendo tais atividades semelhantes às atividades da Nistatina (AU).

Candidoses are usually treated with antifungals. However, the effect of these drugs is usually compromised by microbial resistance and adverse effects. In this sense, the increase in the prevalence and complexity of multidrug-resistant microorganisms to antimicrobials have incited the search for complementary and alternative therapies capable of acting effectively against the emerging resistance to medicines. Therefore, the objective of this study was to comparatively evaluate the antimicrobial action and antibiofilm potential, in vitro, between antimyrobial photodynamic therapy (PDT) with methylene blue, phytotherapy, using hydroethanolic extract of Spondias mombin L (EHSM)and the probiotic Lactobacillus rhamnosus (PLR) in the control of yeasts of the genus Candida: Candida albicans, Candida tropicalis and Candida parapsilosis. This is an experimental, in vitro, analytical and quantitative study in which the inhibitory activity of microbial growth and antibiofilm activity of the following alternative therapies were investigated in triplicate: TFDA, EHSM and PLR, using 100.000UI/mL as positive control. Regarding the statistical analysis, in addition to the descriptive interpretation, the Two-Way ANOVA test and the Tukey test were applied. Thus, it was observed that all therapies tested exhibited antifungal and antibiofilm activities. However, when comparing these activities between them and still with Nystatin, it was found that: TFDA showed the highest inhibitory activity of microbial growth (p <0.05), similar to Nystatin, followed by the EHSM, exhibiting the PLR the lowest antifungal activity and the TFDA together with the EHSM represented the therapies with higher antibiofilm activity (p <0.0001), acting both similarly to Nystatin. In this sense, it was possible to conclude that all the therapies studied have antifungal and antibiofilm activities against the strains of the genus Candida tested, especially the inhibitory activity of microbial growth of TFDA and the antibiofilm activity of TFDA and EHSM, similar to the activities of Nistatina (AU).

The Use of Lasers and Light Devices in Acne Management: An Update.

Acne vulgaris is a disease of the pilosebaceous unit and the most common inflammatory dermatosis worldwide. It is also associated with significant economic burden. Limitations of conventional topical and systemic treatments include long treatment course, intolerable adverse effects, antibiotic resistance, and patient compliance. Therefore, laser and light-based interventions present as alternative options over the past decade and have been used in combination with conventional pharmacological therapies and other physical modalities. An updated overview on the use of lasers and light-based devices in acne management is presented to help clinicians understand the safety and efficacy of these treatment options. The effectiveness of neodymium:yttrium aluminum garnet (Nd:YAG) for treating acne is supported by more high-level studies compared with other laser devices. There is limited evidence to support the use of CO2 lasers, potassium titanyl phosphate lasers, and 1565-nm non-ablative fractional lasers for treating acne. Among light devices, photodynamic therapy is the most studied, showing higher efficacies than some of the conventional topical and oral acne therapies. Intense-pulsed light and blue light therapies also show favorable outcomes. A limitation is that most studies are non-randomized and lack a control group, and report on a variety of device settings, treatment regimens, and outcome measures, making it challenging to summarize and generalize findings. Although the use of laser and light devices to treat acne is promising, further work with randomized controlled study designs and larger sample sizes will provide improved guidance on the application of these modalities.

Antimicrobial and antibiofilm photodynamic therapy against vancomycin resistant Staphylococcus aureus (VRSA) induced infection in vitro and in vivo.

Biofilm mediated infection caused by multi-drug resistant bacteria are difficult to treat since it protects the microorganisms by host defense system, making them resistant to antibiotics and other antimicrobial agents. Combating such type of nosocomial infection, especially in immunocompromised patients, is an urgent need and foremost challenge faced by clinicians. Therefore, antimicrobial photodynamic therapy (aPDT) has been intensely pursued as an alternative therapy for bacterial infections. aPDT leads to the generation of reactive oxygen species (ROS) that destroy bacterial cells in the presence of a photosensitizer, visible light and oxygen. Here, we elucidated a possibility of its clinical application by reducing the treatment time and exposing curcumin to 20 J/cm2 of blue laser light, which corresponds to only 52 s to counteract vancomycin resistant Staphylococcus aureus (VRSA) both in vitro and in vivo. To understand the mechanism of action, the generation of total reactive oxygen species (ROS) was quantified by 2'-7'-dichlorofluorescein diacetate (DCFH-DA) and the type of phototoxicity was confirmed by fluorescence spectroscopic analysis. The data showed more production of singlet oxygen, indicating type-II phototoxicity. Different anti-biofilm assays (crystal violet and congo red assays) and microscopic studies were performed at sub-MIC concentration of curcumin followed by treatment with laser light against preformed biofilm of VRSA. The result showed significant reduction in the preformed biofilm formation. Finally, its therapeutic potential was validated in skin abrasion wistar rat model. The result showed significant inhibition of bacterial growth. Furthermore, immunomodulatory analysis with rat serum was performed. A significant reduction in expression of proinflammatory cytokines TNF-α and IL-6 were observed. Hence, we conclude that curcumin mediated aPDT with 20 J/cm2 of blue laser treatment (for 52 s) could be used against multi-drug resistant bacterial infections and preformed biofilm formation as a potential therapeutic approach.

Pathological Mechanism of Photodynamic Therapy and Photothermal Therapy Based on Nanoparticles.

The ultimate goal of phototherapy based on nanoparticles, such as photothermal therapy (PTT) which generates heat and photodynamic therapy (PDT) which not only generates reactive oxygen species (ROS) but also induces a variety of anti-tumor immunity, is to kill tumors. In addition, due to strong efficacy in clinical treatment with minimal invasion and negligible side effects, it has received extensive attention and research in recent years. In this paper, the generations of nanomaterials in PTT and PDT are described separately. In clinical application, according to the different combination pathway of nanoparticles, it can be used to treat different diseases such as tumors, melanoma, rheumatoid and so on. In this paper, the mechanism of pathological treatment is described in detail in terms of inducing apoptosis of cancer cells by ROS produced by PDT, immunogenic cell death to provoke the maturation of dendritic cells, which in turn activate production of CD4+ T cells, CD8+T cells and memory T cells, as well as inhibiting heat shock protein (HSPs), STAT3 signal pathway and so on.

A Flexi-PEGDA Upconversion Implant for Wireless Brain Photodynamic Therapy.

Near-infrared (NIR) activatable upconversion nanoparticles (UCNPs) enable wireless-based phototherapies by converting deep-tissue-penetrating NIR to visible light. UCNPs are therefore ideal as wireless transducers for photodynamic therapy (PDT) of deep-sited tumors. However, the retention of unsequestered UCNPs in tissue with minimal options for removal limits their clinical translation. To address this shortcoming, biocompatible UCNPs implants are developed to deliver upconversion photonic properties in a flexible, optical guide design. To enhance its translatability, the UCNPs implant is constructed with an FDA-approved poly(ethylene glycol) diacrylate (PEGDA) core clad with fluorinated ethylene propylene (FEP). The emission spectrum of the UCNPs implant can be tuned to overlap with the absorption spectra of the clinically relevant photosensitizer, 5-aminolevulinic acid (5-ALA). The UCNPs implant can wirelessly transmit upconverted visible light till 8 cm in length and in a bendable manner even when implanted underneath the skin or scalp. With this system, it is demonstrated that NIR-based chronic PDT is achievable in an untethered and noninvasive manner in a mouse xenograft glioblastoma multiforme (GBM) model. It is postulated that such encapsulated UCNPs implants represent a translational shift for wireless deep-tissue phototherapy by enabling sequestration of UCNPs without compromising wireless deep-tissue light delivery.

Light-Emitting Diode-Based Photodynamic Therapy for Photoaging, Scars, and Dyspigmentation: A Systematic Review.

BACKGROUND: Light-emitting diodes (LEDs) may be used as an activating light source for photosensitizers in photodynamic therapy (PDT), a form of noninvasive phototherapy. Photodynamic therapy for aesthetic dermatologic conditions has demonstrated skin rejuvenating effects. OBJECTIVE: To evaluate the safety and efficacy of PDT using LEDs to treat aesthetic dermatologic conditions including photoaged skin, scarring, and dyspigmentation. MATERIALS AND METHODS: A search of PubMed and EMBASE databases was conducted through May 31, 2019, to identify studies that used LEDs as a light source for PDT and evaluated cosmetic improvements as the primary outcome measure. RESULTS: A total of 24 original articles were included in the authors' systematic review. The available evidence supports methyl aminolevulinate or 5-aminolevulinic acid incubation followed by LED treatment for global improvement of skin quality, including smoother texture, reduction of rhytides, and improvement of scars. Histologic analysis for global skin improvement demonstrated increased collagen fibers and decreased elastin fibers after LED-mediated PDT. CONCLUSION: Light-emitting diode-based PDT seems to have beneficial effects for photoaging, scars and dyspigmentation. A paucity of high-quality studies using LED-based PDT for aesthetic outcomes was found, highlighting the need for well-designed randomized control trials on this topic.

Biomineralization-inspired nanozyme for single-wavelength laser activated photothermal-photodynamic synergistic treatment against hypoxic tumors.

Hypoxia, one of the features of most solid tumors, can severely impede the efficiency of oxygen-dependent treatments such as chemotherapy, radiotherapy and type-II photodynamic therapy. Herein, a catalase-like nanozyme RuO2@BSA (RB) was first prepared through a biomineralization strategy, and a high efficiency near-infrared photosensitizer (IR-808-Br2) was further loaded into the protein shell to generate the safe and versatile RuO2@BSA@IR-808-Br2 (RBIR) for the imaging-guided enhanced phototherapy against hypoxic tumors. RB not only acts like a catalase, but also serves as a photothermal agent that speeds up the oxygen supply under near-infrared irradiation (808 nm). The loaded NIR photosensitizer could immediately convert molecular oxygen (O2) to cytotoxic singlet oxygen (1O2) upon the same laser irradiation. Results indicated that RBIR achieved enhanced therapeutic outcomes with negligible side effects. Features such as a simple synthetic route and imaging-guided and single-wavelength-excited phototherapy make the nanozyme a promising agent for clinical applications.

Photochemical /Photocytotoxicity Studies of New Tetrapyrrolic Structures as Potential Candidates for Cancer Theranostics.

BACKGROUND: Detailed photochemical and photocytotoxicity studies of two new porphyrins: 5,10,15,20-meso-tetrakis-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.1) and 5-(4-hydroxy-3- methoxyphenyl)-10,15,20-tris-(4-acetoxy-3-methoxyphenyl)porphyrin (P2.2) are reported, as potential candidates for theranostics. For powdered samples of P2.1 and P2.2 adsorbed onto a powdered biocompatible substrate, polyethylene glycol (PEG), a concentration study was performed, correlating the fluorescence emission intensity with sample absorption to determine the useful concentration range for photodynamic therapy of cancer (PDT) in which aggregation does not occur. Cytotoxicity studies were performed in dark and illuminated conditions. METHODS: The laser induced luminescence set-up is home-made, a N2 laser is used as the excitation source and a time gated charged-coupled device (ICCD) as the detector. Fluorescence lifetime determinations were made using pulsed light sources from the excitation LEDs and measures of the fluorescence intensities at different time delays after the excitation pulse. The singlet oxygen formation quantum yields ΦΔ measurements were obtained by comparing the total area of the emission spectra for the reference compound and also for the samples under study in the same solvent and with the same optical density at the excitation wavelength (405 nm). An integrating sphere for relative and absolute measurements was used in this work as an alternative methodology to obtain the values for the fluorescence emission quantum yields (ΦF) of the adsorbed porphyrin under study. The cytotoxicity evaluation was made in the dark and under irradiation, using four different human tumor cell lines and one non-tumor primary cell culture. RESULTS: In order to establish the useful range of concentrations of the sensitizer for PDT, and due to the use of powdered samples, a special methodology was needed: the variations of the fluorescence lifetimes and fluorescence quantum yields were evaluated as a function of the concentration of the dye, measured by (1-R)*fdye. Both ΦF and τF are constant in the range from 0.002 to about 0.050 µmol g-1, and only after that a concentration quenching effect becomes visible, decreasing both ΦF and τF. This methodology is based in the correlations established between the Remission Function values and ΦF and τF obtained for increasing values of the sensitizer concentrations. CONCLUSIONS: The study of the aggregation effects of P2.1 and P2.2 porphyrins into a PEG matrix allowed us to determine the usable concentration range for photodynamic therapy use, where the aggregation of porphyrins decreases, therefore reducing the PDT action. The use of an integrating sphere for relative and absolute measurements of fluorescence quantum yields and also the lifetime studies as a function of the dye loading confirms the useful range for the use of P2.1 and P2.2 in PEG as powdered samples. The determination of the GI50, the porphyrin concentration which inhibits 50% of the cell growth, evidences that P2.2, the A3B porphyrin overtakes P2.1 (the A4 porphyrin) in terms of PDT efficiency and both porphyrins are much better PDT agents than the unsubstituted porphyrin, TPP. These data clearly show that porphyrins P2.2 and P2.1 exhibit an excellent behaviour in terms of its photocytotoxicity. These results encourage us to pursuit in the study of this family of porphyrins in which a balance of hydrophobic versus hydrophilic substituents in the phenyl group was achieved.

Antimicrobial Photodynamic Therapy in the Endodontic Treatment of Deciduous Teeth: In Vivo Pilot Study

Abstract Objective: To evaluate the Antimicrobial Photodynamic Therapy (aPDT) in infected deciduous teeth by quantifying the viable bacteria in root canal treatment. Material and Methods: Radicular canal cultures were collected (n= 10). Four intra-canal samples were collected at four different times in each of the sampled teeth, as follows: Time 1 (T1), baseline: After opening the pulp-chamber; Time 2 (T2): After application of aPDT; Time 3 (T3): After mechanical, chemical manipulation; Time 4 (T4): After a second application of aPDT. The aPDT was performed with a 4J/cm energy low-intensity diode, together with 0.005% methylene blue as a photosensitizer. The clinical specimens were taken to the laboratory for a bacteria count (colony forming units) and the results were statistically analyzed using the Friedman and Wilcoxon tests, with a significance level of α=0.05. Results: Statistical differences were seen between the numbers of bacteria at times T1-T2, T1-T3 and T1-T4 on the cultivated plates. However, no significant statistical differences were observed between the number of bacteria in samples T2-T3, T2-T4 and T3-T4. Conclusion: Antimicrobial photodynamic therapy can be a good co-adjuvant in root canal decontamination of necrotic primary teeth.

In Vitro Evaluation of the Antibacterial Effect of Photodynamic Therapy with Methylene Blue

Abstract Objective: To evaluate, in vitro, the effect of photodynamic therapy (PDT) compared to laser therapy and the use of a photosensitizer alone. Material and Methods: The following therapies were used: PDT, laser therapy and photosensitizer alone. For PDT, methylene blue (MB) at different concentrations and red laser InGaAlP 660nm were used. For the use of low-power laser (LPL) alone, red laser InGaAlP 660 nm and infrared laser AsGaAl, 830 nm, both in continuous emission were used. Standard ATCC strains of Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) species were used. The antibacterial effect of PDT was quantified by the diameter of the inhibition halos. Results: PDT (LPL 660 nm, 320 J/cm2) with MB at concentration of 50 µg/mL showed antibacterial efficacy only when tested against S. aureus and E. coli strains, as well as with the isolated use of MB at the same concentration. Using LPL alone, whether red or infrared, with different dosimetry, no antibacterial effect was observed. In none of the therapeutic modalities used, P. aeruginosa inactivation was observed. Conclusion: Antibacterial effects of PDT (LPL 660 nm + MB 50 µg/mL) were observed for S. aureus and E. coli, as well as with the isolated use of MB (50 µg/mL). For P. aeruginosa, no antibacterial effect with any of the protocols recommended in the study was observed.

Optimization of sapphire capillary needles for interstitial and percutaneous laser medicine.

Sapphire capillary needles fabricated by edge-defined film-fed growth (EFG) technique hold strong potential in laser thermotherapy and photodynamic therapy, thanks to the advanced physical properties of sapphire. These needles feature an as-grown optical quality, their length is tens of centimeters, and they contain internal capillary channels, with open or closed ends. They can serve as optically transparent bearing elements with optical fibers introduced into their capillary channels in order to deliver laser radiation to biological tissues for therapeutic and, in some cases, diagnostic purposes. A potential advantage of the EFG-grown sapphire needles is associated with an ability to form the tip of a needle with complex geometry, either as-grown or mechanically treated, aimed at controlling the output radiation pattern. In order to examine a potential of the radiation pattern shaping, we present a set of fabricated sapphire needles with different tips. We studied the radiation patterns formed at the output of these needles using a He-Ne laser as a light source, and used intralipid-based tissue phantoms to proof the concept experimentally and the Monte-Carlo modeling to proof it numerically. The observed results demonstrate a good agreement between the numerical and experimental data and reveal an ability to control within wide limits the direction of tissue exposure to light and the amount of exposed tissue by managing the sapphire needle tip geometry.

Near-Infrared Light-Harvesting Fullerene-Based Nanoparticles for Promoted Synergetic Tumor Phototheranostics.

A synergetic phototheranostic system, combining diagnostic photo-imaging and phototherapies [such as photothermal therapy and photodynamic therapy (PDT)], shows great potential in today's tumor precise therapy. Herein, we fabricate near-infrared (NIR) light-harvesting fullerene-based nanoparticles (DAF NPs) for photoacoustic (PA) imaging-guided synergetic tumor photothermal and PDT. The fullerene derivatives (DAF) absorbing in the NIR region have been synthesized by conjugating NIR-absorbing antenna with fullerene. In addition, DAF NPs with good biocompatibility have been fabricated via a nanoprecipitation approach. The as-prepared DAF NPs can accumulate and generate PA signals around the tumor site 6 h post injection via enhanced permeability and retention effect in vivo. More importantly, the DAF NPs exhibit better reactive oxygen species and heat generation efficacy compared with fullerene and antenna nanoparticles (DA NPs), respectively. Further in vitro and in vivo studies demonstrate that DAF NPs can effectively inhibit tumor growth through synergetic photodynamic and photothermal therapies, which provides a new sight of photosensitizer design for enhanced cancer phototheranostics.

Carbon Dot-Passivated Black Phosphorus Nanosheet Hybrids for Synergistic Cancer Therapy in the NIR-II Window.

Metal-free layered black phosphorus (BP) nanosheets with an excellent photothermal effect and large surface areas have been widely applied in biomedicine but are easily oxidized in ambient conditions yielding insulating phosphorus oxides adsorbed on its surface. Several chemical-functionalized strategies have been explored to protect thin layers of BP; however, the performance of passivated BP often decreases significantly, falling behind the single BP due to the strong structure perturbation. Herein, we designed and constructed 0D/2D hybrid photothermal agents by assembling NIR-II-responsive carbon dots (NIR-II-CDs) on BP nanosheets. NIR-II-CDs improve the ambient stability of BP by isolating them from water and oxygen and enhance the photothermal properties of BP nanosheets. Such NIR-II-CD/BP hybrids strengthen the light-harvesting ability, achieving high photothermal conversion efficiencies in the NIR-I (77.3%) and NIR-II (61.4%) windows, which is significantly higher than that of pristine BP (49.5 and 28.4% at 808 and 1064 nm). Owing to the intrinsic advantage of 1064 nm laser and the excellent PTT effect of our NIR-II-CD/BP hybrids, complete tumor eradication was realized in a deep-tissue tumor model.

Biomimetic Carriers Based on Giant Membrane Vesicles for Targeted Drug Delivery and Photodynamic/Photothermal Synergistic Therapy.

Membrane vesicles derived from live cells show great potential in biological applications due to their preserved cell membrane properties. Here, we demonstrate that cell-derived giant membrane vesicles can be used as vectors to deliver multiple therapeutic drugs and carry out combinational phototherapy for targeted cancer treatment. We show that therapeutic drugs can be efficiently encapsulated into giant membrane vesicles and delivered to target cells by membrane fusion, resulting in synergistic photodynamic/photothermal therapy under light irradiation. This study highlights biomimetic giant membrane vesicles for drug delivery with potential biomedical application in cancer therapeutics.

Biodegradable Hollow MoSe2/Fe3O4 Nanospheres as the Photodynamic Therapy-Enhanced Agent for Multimode CT/MR/IR Imaging and Synergistic Antitumor Therapy.

Photodynamic therapy (PDT) is considered as one of the most effective cancer treatment strategies because of its minimally invasive and high efficiency. On account of the correlation between PDT and photocatalytic oxidation, the hollow MoSe2/Fe3O4 (MF-2) nanoheterostructure was constructed to enhance PDT as shown in this paper. The size and the hollow structure can be well controlled by the addition of F-127. MoSe2/Fe3O4 reveals the twofold reactive oxygen species (ROS) generation in contrast to the pure MoSe2, which is ascribed to the effective separation of photogenic charges. The novel hollow structure also supplies a lot of cavities for perfluorocarbon (PFC) and O2 loading, and O2@PFC@MF-2 can effectively overcome the hypoxic microenvironment to further cause more than 3 times ROS production. Moreover, the narrow band gap and hollow structure also make sure that the strong near-infrared (NIR) light absorption and high photothermal conversion efficiency is as high as 66.2%. Furthermore, the combination of Fe3O4 can further accelerate the effective biodegradation capacity of MF-2 because of the repeated endogenous redox reaction to form water-soluble MoVI-oxide species. Meanwhile, doxorubicin (Dox, anticancer drug) was assembled onto the MF-2@PEG nanomaterials through π-π staking and electrostatic interaction for chemotherapy. O2@PFC@MF-2@PEG/Dox possesses the potential application in triple-model computed tomography, magnetic resonance, and infrared (CT/MR/IR) imaging-guided photothermal/photodynamic/chemotherapy (PTT/PDT/chemotherapy) nanodiagnosis platforms.

Mn-Porphyrin-Based Metal-Organic Framework with High Longitudinal Relaxivity for Magnetic Resonance Imaging Guidance and Oxygen Self-Supplementing Photodynamic Therapy.

A nanoplatform for magnetic resonance imaging guidance and oxygen self-supplementing photodynamic therapy (PDT) was constructed on the basis of a porous metal-organic framework (PCN-222(Mn)), which was built by simple Mn-porphyrin ligands and biocompatible Zr4+ ions. Because of the good dispersibility of Mn3+ in the open framework and the high water affinity of the channel, PCN-222(Mn) exhibits a high longitudinal relaxivity of ∼35.3 mM-1 s-1 (1.0 T). In addition, it shows good catalytic activity for the conversion of endogenous hydrogen peroxide into oxygen, thereby improving tumor hypoxia during photodynamic therapy. The intravenous injection of PCN-222(Mn) into tumor-bearing mice mode provided good T1-weighted contrast of the tumor site and effectively inhibited tumor growth upon a single-laser irradiation. The findings provide insights for the development of multifunctional theranostic nanoplatforms based on simple components.

Assessment of sensitivity of selected Candida strains on antimicrobial photodynamic therapy using diode laser 635 nm and toluidine blue - In vitro research.

BACKGROUND: Photodynamic therapy is believed to be a promising treatment for Candida infections. This study evaluated the efficacy of antimicrobial photodynamic therapy (aPDT) using the 635 nm diode laser light and toluidine blue (TB) in the elimination of selected Candida species cultured on acrylic surface. METHODS: 108 acrylic plates (Methyl Methacrylate Polymer, routinely used for the production of prosthetic dentures) were placed in three sterile Petri dishes and poured with prepared suspensions of Candida strains: C. albicans, C. glabrata, and C. krusei. After all procedures of fungi incubation, fungal biofilm was visible on the plates' surfaces. The acrylic plates were divided into nine study groups (B) and nine control groups (K) for further experiments. In the study groups, the acrylic plates with fungal biofilm were immersed in TB and afterwards laser irradiation was applicated with different exposure parameters (groups: B1 - 400 mW, 24 J/cm2, 30 s; B2 - 300 mW, 18 J/cm2, 30 s; B3 - 200 mW, 12 J/cm2, 30 s) separately for each Candida species. The control groups contained following parameters: no exposure to laser light or TB, treatment only with TB without laser irradiation, or only laser irradiation without previous immersion in TB. Calculations of colony forming units (CFUs) were conducted by using aCOlyte (Synbiosis). Differences in CFUs were analyzed by the Wilcoxon test. RESULTS: In all study groups, the reduction in CFUs was statistically significant. The differences in CFUs before and after intervention were insignificant. The K3 C.a. control group showed a statistical reduction of Candida albicans after laser irradiation. CONCLUSION: Our study confirmed the efficacy of aPDT against C. albicans, C. glabrata and C. krusei being dependent on the laser parameters and the type of fungus. The advantage of this study is the validation of aPDT effectiveness in in vitro studies to transpose this data into future clinical trials using photodynamic therapy in the treatment of oral candidiasis.

Effect of phototherapy on dentin bond strength and microleakage when bonded to resin with different conditioning regimes.

AIM: To assess the efficacy of phototherapy on bond strength and microleakage of bulk fill composites in comparison to conventional dentin surface treatments. MATERIALS AND METHODS: Ninety human third molars were divided into 3 groups (n = 30 each) according to surface conditioning treatment. Group 1 (Etch and Bond) EB, group 2 was treated with Er,Cr: YSGG (ECL) and group 3 was treated with a diode laser (DL). Based on the type of bulk fill resin composite, samples were divided into six sub-groups. In sub-group 1, 2 and 3 (n = 15) build-up was done using ZirconCore (ZC) and these subgroups were named as EB-ZC, ECL-ZC and DL-ZC. In subgroup 4,5,6 (n = 15) MulticCore Flow (MC) was used for core build-up and these subgroups were named as EB-MC, ECL-MC, DL-MC. For shear bond strength (SBS) all the samples were exposed to loads using a universal testing machine. Five samples each from all subgroups were immersed in methylene blue dye for 24 h prior to microleakage testing. Data were assessed using analysis of variance and Tukey multiple comparisons test. RESULTS: Among all the groups the lowest bond strength was achieved in DL-ZC [10.45(0.459)]. Similarly, the highest bond strength was attained in EB-MC[17.84(0.925)]. The highest microleakage scores amongst different group was exhibited in DL-ZC [82.45(39.459)] whereas, the lowest microleakage scores were displayed in EB-MC [31.21(15.92)]. CONCLUSION: Phototherapy in the form of Er,Cr:YSGG laser showed comparable adhesive bond outcomes to conventional etch and bond dentin conditioning techniques. Moreover, Multicore bulk fill material showed better bond strength and microleakage scores than zirconium particle infiltrated bulk fill composite in the presence of dentin phototherapy.

Near-infrared light-mediated photodynamic/photothermal therapy nanoplatform by the assembly of Fe3O4 carbon dots with graphitic black phosphorus quantum dots.

BACKGROUND: Recently, combined photodynamic therapy (PDT) and photothermal therapy (PTT) has become a desired treatment for cancer. However, the development of economic, high-efficiency, and safe photosensitizers/photothermal agents remains a significant challenge. METHODS: A novel nanocomposite has been developed via the assembly of iron oxide carbon dot (Fe3O4-CDs) nanoparticles and black phosphorus quantum dots (genipin [GP]-polyglutamic acid [PGA]-Fe3O4-CDs@BPQDs), and this nanocomposite shows a broad light-absorption band and a photodegradable character. RESULTS: In vitro and in vivo assays indicated that GP-PGA-Fe3O4-CDs@BPQDs were highly biocompatible and exhibited excellent tumor-inhibition efficacy, due to the synergistic PTT and PDT via a near-infrared laser. Importantly, in vivo tumor magnetic resonance imaging (MRI) results illustrated that GP-PGA-Fe3O4-CDs@BPQDs can be specifically applied for enhanced T2 MRI of tumors. This work presents the first combined application of a PDT and PTT effect deriving from BPQDs and MRI from Fe3O4-CDs, which may promote utilization of black BPQDs in biomedicine. CONCLUSION: As expected, GP-PGA-Fe3O4-CDs@BPQDs displayed a dramatically enhanced ability to destroy tumor cells, due to the synergistic combination of PTT and PDT.