The results showed that 20%, 50% and 90% degradation of MO in 40 minutes was observed in dark, visible light and UV light, respectively. To further explore the biological potential of synthesized Ag/CuO nanocomposite, we also evaluated it for an inactivation of bacteria where Escherichia coli has 17(±0.5 mm) and Staphylococcus aureus has 20 (±0.6 mm) zone of inhibition in light. The results showed that reactive oxygen species (ROS) were produced in the presence of light and Ag/CuO. These ROS are the main source of inactivation of bacteria. The prepared nanomaterial has also good efficiency against DPPH stabilization. Further study is required to investigate the hidden applications of the as synthesized nanomaterials.Background Periodontal disease (PD) is a chronic inflammatory disease caused by the presence of microbial biofilm. Nobiletin The aim of this study was to evaluate antimicrobial effect of antimicrobial photodynamic therapy (APDT) mediated by methylene blue (MB) in monomer form on A. actinomycetemcomitans and P. gingivalis. Methods A. actinomycetemcomitans ATCC 29523 and P. gingivalis ATCC 33577 were cultured on anaerobic jars at 37 °C for 48 h, and we tested APDT in the presence of 0.25% sodium dodecyl sulfate (SDS) in phosphate-buffered saline (PBS) or in PBS alone. APDT was carried out with 100 µM MB under laser radiation (PhotolaseIII, DMC, Brazil) at ʎ =660 nm and parameters as following (P =100 mW; I =250 mW/cm2, and doses of 15, 45 and 75 J/cm2). Results Following APDT, PBS groups of A. actinomycetemcomitans presented 4 Logs of microbial death after 5 min irradiation. However, there was no bacterial reduction in SDS groups. On the other hand, P. gingivalis was sensitive to APDT in the presence of 0.25% SDS with 2 logs reduction from dark toxicity. Conclusion The presence of 0.25% SDS can lead to different responses depending on the different microbial species.In this case report, we present a successful outcome of conservative treatment in a patient with oral mucosal necrosis. Quantitative Light induced Fluorescence (QLF) was used to evaluate progression and determine the medication period. Histology revealed microbiological differences between red fluorescing and non-fluorescing sites on QLF images. QLF technology could be widely used for detecting bacterial infections or necrotic lesions in oral and maxillofacial regions.The World today is facing a great effort for the control of infections.•Nowadays COVID-19 is the large global outbreak and is the major public health issue.•This letter to Editor highlighted the well-established photodynamic therapy protocol as a tool to decrease the viral and bacterial load in the respiratory tract.Leishmaniasis is a serious neglected disease that affects 14 million people around the world. The currently available drugs for treatment present several drawbacks such as low efficacy and severe side effects, contributing to patients' low compliance. Photodynamic therapy (PDT) is rising as a promising alternative for treatment of cutaneous leishmaniasis, mainly considering its topical administration that circumvents any potential adverse effects commonly related to oral/parenteral administration. PDT depends on the interaction between a light-sensitive compound (photosensitizer - PS), light and molecular oxygen. The reaction generates reactive oxygen species (ROS) which induce cell death by oxidative stress. The main goal of this study is to demonstrate the antileishmanial effect of three chlorin derivatives (CHL-OH-A, CHL-OH-B, CHL-TRISMA) using PDT, as well as to investigate their cell death pathway on Leishmania amazonensis promastigote forms after chlorine-PDT application. The chlorin derivatives herein studied did not exhibit aggregates in aqueous medium and showed fast accumulation in Leishmania acidic compartments. CHL-OH-A exhibited the highest antiparasitic activity at 24 h (0.33 µmol L-1) and 48 h (0.14 µmol L-1) after irradiation at 660 nm (6.0 Jcm-2). CHL-OH-A, CHL-OH-B and CHL-TRISMA molecules induced the cell death of parasites mainly by an apoptotic-like process in the presence of light. These chlorin derivatives are 80-fold more active against Leishmania when compared to other PSs reported in the literature. In this study, we have shown that these amphiphilic chlorins, and in particular, CHL-OH-A, exert an interesting leishmanicidal activity suggesting that the use of these PSs associated with PDT could be a promising strategy for treatment of cutaneous leishmaniasis.Aim Metronomic photodynamic therapy (mPDT) with a longer irradiation time and lower energy compared with acute (or classic) photodynamic therapy (aPDT) is a more effective treatment than aPDT for tumor cells, especially colorectal cancer. However, the underlying mechanisms of the superior effects of mPDT are unknown. Methods we used SWATH-MS (sequential window acquisition of all theoretical mass spectra) to identify differentially expressed proteins (DEPs) specific to aPDT (conventional fluence rate, 20 mW/cm2, 4 min 10 s), mPDT (metronomic fluence rate, 0.4 mW/cm2, 3.5 h), and control groups of SW837 cells. The photosensitizer used in both PDT methods was aminolevulinic acid which were incubated with the cells before irradiation. Results A total of 6805 proteins were identified in the three groups of SW837 cells. aPDT induced 333 DEPs and mPDT induced 1716 DEPs compared with the control. We identified 185 common DEPs in the two PDT groups, 148 different DEPs in the aPDT group, and 1531 different DEPs in the mPDT group. Most of the 185 common DEPs were involved in the extracellular component, participated in the processes of vesicle transport and secretion, binding, and hydrolase/catalytic activity. They were also involved in PI3K-Akt, cGMP-PKG, RAS, and aAMP signaling pathways. In addition, the 1531 different DEPs in the mPDT group participated in similar processes and molecular functions, but in a more complex manner than those in the aPDT group. Conclusion our proteome data suggest that mPDT has a complex tumor destruction mechanism with more involved proteins compared with aPDT, which may explain the better tumor killing effect of mPDT.