Journal of Photochemistry and Photobiology最新文献

A nanosized TiO₂-Ag nanoparticulate doped photocatalytic adhesive membrane, recently patented as WiWell™ (WippyIdea®), has been used in the indoor environment of public transportation to decrease the airborne microbiome and the microbial charge on handy surfaces, to ensure a safe context to people using and or crowding the place. While the simple cleaning process with chemical sanitizers reached a reduction of indoor microbial contamination as high as 40%, the use of the photocatalytic films lowered the microbial pollution, measured via ATP-bio-luminescence, to values ≥ 94%, ensuring much safer indoor conditions for people travelling. This pilot study, performed on the field, encourages further research to support this patented technology and apply it everywhere.

Melanopsin is a photopigment found in a subset of retinal ganglion cells that is responsible for generating a series of responses to light in organisms, such as circadian rhythm regulation, pupillary light reflex, and body temperature control. The role of each melanopsin gene in the vertebrate retina is still not fully elucidated and a diversity of expression patterns of this photopigment can be observed in retinas of different vertebrate species. Owls are an excellent model for studying the role of melanopsin due to the diversity of species, which may present diurnal, nocturnal, or cathemeral habits. The purpose of this study was to characterize the expression of melanopsin genes in the retina of four different owl species from the Strigidae family (Athene cunicularia, Asio clamator, Glaucidium brasilianum, and Megascops choliba) through genetic and phylogenetic analysis. The specimens were euthanized, and the retinas were collected for RNA extraction and cDNA transcription. cDNA was used in the polymerase chain reaction (PCR) with subsequent sequencing to identify melanopsin genes expressed in the retina of owls. For the quantitative analysis of gene expression, real-time PCR was performed. The phylogenetic reconstruction was obtained by the maximum likelihood. The results showed that owls express both melanopsin genes, Opn4x and Opn4m, with different patterns of expression among the species. The expression of the Opn4x gene was two times higher in Asio clamator (nocturnal) compared to A. cunicularia (cathemeral), Glaucidium brasilianum (diurnal), and Megascops choliba (nocturnal). On the other hand, the expression of Opn4m was about two times lower in the cathemeral, A. cunicularia compared to the other three species. These results might indicate functional differences of the Opn4x and Opn4m genes among species, related to circadian rhythm regulation. Further investigation in owls at other times of the day will bring light to the circadian pattern of melanopsin expression in these species and its correlation with the different patterns of daily activity.

Chlorophyll fluorescence transients are recognized as one of the most efficient methods for assessing plant photosynthetic efficiency under stressful conditions. The focus of this research was to investigate R. gangetica's photosynthetic performance under several abiotic stressors, including cold, heat, flooding, salinity, and UV. Chlorophyll (chl), proline, malondialdehyde (MDA) contents, specific energy fluxes (per Q_A-reducing PSII reaction center) such as ABS/RC, TR₀/RC, ET₀/RC, DI₀/RC, phenomenological fluxes, (ABS/CSm, TR/CSm, ETo/CSm), quantum yields (ɸPo, ɸEo, ɸDo), and performance indices (PI_cs and PI_abs) were analyzed. Chl content, Fm, Fv/Fm, and PIcs were recognized as highly sensitive parameters to all abiotic stresses. The results of the present study clearly show that R. gangetica has distinct biochemical and physiological strategies for dealing with the negative effects of various abiotic stressors. On the basis of present investigations, tolerance potential against several abiotic stimuli in R. gangetica can be ranked as follows Sl, UV, Ht, Fd, and Cd.

Prolonged inflammation and impaired redox balance are important causes of delayed wound healing. Photobiomodulation (PBM) enhances delayed wound healing by modulating various cellular signaling pathways involved in the wound healing process. This study aimed to reveal the mechanisms of action of PBM in accelerating wound healing in a diabetic adipose derived stem cell (ADSC)-fibroblast co-culture cell model. ADSC-fibroblast co-culture cells were divided into normal (N), normal wounded (NW), diabetic (D) and diabetic wounded (DW) groups and were irradiated (wavelength: 660 or 830 nm; energy density: 5 J/cm²). Unirradiated cells (0 J/cm²) served as controls. Wound closure/migration was recorded in NW and DW groups using light microscopy. Signaling pathway proteins (PI3 kinase, AKT and FoxO1) modulated by PBM were evaluated by immunofluorescence and western blotting. ELISA was used to measure the levels of antioxidants (HMOX1, SOD and CAT). PBM treatment effectively enhanced cell migration and wound closure in irradiated groups. Furthermore, PBM elevated PI3 kinase and AKT signaling proteins that in turn elevated antioxidant levels. These results demonstrate that PBM at 660 and 830 nm increases migration of co-culture cells and is mediated at least in part through the activation/regulation of the PI3K/AKT/FoxO1 signaling pathway. PBM could be a promising therapeutic approach which can be used in chronic wound treatment.

The visual processing of vertebrates initiates in the retina upon the absorbance of photons by the photoreceptors. These neurons contain the photopigments that are formed by a membrane protein, opsin or rhodopsin, covalently bound to a chromophore. The peak spectral sensitivity (λ_max) of the photopigment is determined by the protein structure and the type of chromophore associated, 11-cis-retinal (A₁-based chromophore) or 3,4-dehydroretinal (A₂-based chromophore). The red-eared turtle, Trachemys scripta elegans, has five A₂-based photopigments, SWS1, SWS2, RH1, RH2, and LWS, with known λ_max at 372, 458, 518, 518, and 617 nm, respectively. We took advantage of this valuable model to investigate the applicability of computational modeling to estimate the λ_max of A₂-based opsins. First, we sequenced the five opsin genes expressed in the retina of T. s. elegans and estimated the opsins λ_max based on known spectral tuning sites. The predictions were consistent with the values described in the literature: 373, 457, 518, 518, and 617 nm, for the SWS1, SWS2, RH1, RH2, and LWS, respectively. Then, we calculated the λ_max using Comparative Modeling for the RH1, RH2, SWS1, and SWS2 opsins and using Threading Modeling for the LWS opsin. The absorption spectrum was analyzed using semiempirical Quantum Mechanical simulations, according to the TD-DFT method, applying the functional B3LYP and 6–31 G basis set. For each model, molecular docking was carried out to find the best positioning of the chromophore. The estimated λ_max of the SWS1, RH1, and RH2 were consistent with known peaks (380, 524, and 520 nm, respectively), while the opsins SWS2 and LWS had considerable shifts compared to known values (478 and 636 nm, respectively). Although the calculated λ_max of the cone opsins had some inconsistencies, the in silico analyses revealed promising results and opened a new methodologic approach for further investigations of vertebrate spectral sensitivity.

Background

Photoaging is mainly caused by ultraviolet radiations inasmuch they can damage the DNA, trigger ROS production, and activate p53/p21 pathway, which cause cell cycle arrest and senescence. The accumulation of senescent cells within the dermis contributes to tissue deregulation and skin carcinogenesis. However, the use of photoprotector molecules could reduce UV-induced damages and prevent photoaging. Therefore, the aim of this study is to evaluate whether the active forms of vitamin B3 (nicotinamide) and the analog of vitamin D3 (calcipotriol) might protect primary human dermal fibroblasts (HDFs) from UVB-induced photoaging.

Methods

HDFs were isolated from a healthy adult donor and stimulated with nicotinamide (25 μM) and calcipotriol (100 nM) for 24h before UVB exposure, and then, cultured for further 24h on vitamin-supplemented media. Then, cell viability, ROS production, DNA damages, senescence markers, protein and gene expression were evaluated.

Results

HDFs treated with nicotinamide and calcipotriol showed better proliferation properties and lower DNA damages due to a reduced UVB-induced ROS production. Consequently, p53/p21 pathway was less active which enhanced cell cycle progression and reduced senescence and cell death.

Conclusions

Overall, our results suggest that nicotinamide and calcipotriol can counteract UVB-induced effects responsible for the onset of skin photoaging.

Patients with long-term or severe inflammatory bowel disease (IBD) are more likely to develop colorectal cancer. The mortality rate of patients with IBD-related colorectal cancer is also higher than that of patients with common colorectal cancer. This study focused on the effect of photobiomodulation (PBM) on dextran sulfate sodium (DSS)-induced colitis and its underlying mechanism. C57 mice were treated with monochromatic light during DSS-induced colitis. Blue light irradiation clearly alleviated DSS-induced colitis, significantly changed the proportion of the relevant immune cell population in the colon, and improved the inflammatory environment of the colon. Moreover, the rhythm gene Brain And Muscle ARNT-Like 1 (Bmal1) is involved in the progression of colitis, and its decreased expression in colitis mice was reversed by blue light irradiation. These data demonstrated that the protective effect of blue light against colitis is mediated by the Bmal1-mediated pathway in macrophages. This study proposes blue light irradiation with specific light intensities as a potential IBD therapy.

Light, an inevitable factor for human life, can have negative effects such as cellular inflammation and thus be toxic to cells. Lipids are important biomolecules that are involved in cellular inflammatory responses. Our research revealed the impact of light on cellular lipids. We discovered that blue light irradiation altered cellular lipidome based on non-targeted lipidomic analysis. Inflammation-related lysophospholipids, arachidonic acid, docosahexaenoic acid, and eicosapentaenoic acid, in particular, were significantly increased. We created opto-PiC, an optolipidomic tool based on the optogenetically engineered cPLA2 enzyme. Light-induced lipidomic changes were reversed by opto-PiC. Furthermore, the results showed that opto-PiC reduced cell death rate under blue light. Overall, our research provided lipidomic insights and optolipidomics approach into light toxicity. This could help the therapy development in the future for inflammation-related disease.

Introduction

Since the 1960s, lasers have been used in dentistry, and their clinical uses have been evaluated. Many dental procedures involve lasers, which are noted for their simplicity, efficiency, comfort, and superiority over older methods. Lasers have been employed in various therapy approaches, from identifying small caries to planning and treating more severe lesions or cancers.

Methodology

To conduct a comprehensive search for our systematic review, we employed three search engines: PubMed, Cochrane, and Google Scholar. Following combinations; Lasers [general dentistry], Laser [soft tissue], and Laser [hard tissue], published in the last five years. After applying inclusion-exclusion criteria, 46 original articles were studied in detail.

Objective

The systematic review aimed to study the long-term outcomes of lasers on soft and hard tissues in dentistry.

Result

Tooth decay, gum disease, biopsy or lesion removal, teeth whitening, and other procedures are performed using lasers. Lasers are frequently utilized because they cause less pain, require less anesthesia and avoid anxiety in patients who are afraid of dental drills and instruments.

Conclusion

Laser technology in clinical dentistry practice is currently at an advanced stage of development and has a bright future. With the expanding use of lasers on both hard and soft tissue in clinical dentistry, treatment planning and prognosis have significantly improved.

Objective

We report on the development and characterization of a UV-C (λ  =  200 – 280 nm, λ_peak = 254 nm) chamber designed for the rapid disinfection of N95 class filtering-facepiece respirators contaminated with SARS-CoV-2 coronaviruses. The device was evaluated against Betacoronavirus strain MHV-3 and its virucidal capacity was evaluated as a function of different applied UV-C doses (UV-C exposure times of 60 s, 120 s, 180 s, and 240 s) using two types of respirators geometry (shell and two-panel shapes, 3M 8801 H and 9920 H, respectively), at eight points of the respirators.

Background

Most chemical disinfection methods are not recommended for N95 masks. UV-C light provided by UVGI lamps (254 nm) is an effective physical agent against viruses and bacteria due to direct photochemical harming effect on DNA/RNA, and can provide rapid disinfection for personal protective equipment such as N95/PFF2 masks.

Results

The device reached a mean elimination rate of 99.9999% of MHV-3 inoculated into all the assessed different points on the tested PFF2 respirator models in a UV-C cycle of just 60 s. Statistical analysis performed through Person´s chi-square test showed no correlation between the viral infectivity reduction and the viral inoculation point (p = 0.512) and the tested respirator models (p = 0.556). However, a correlation was found between the exposure time and the viral infectivity reduction (p = 0.000*), between UV-C and no UV-C exposure. All the tested UV-C exposure times (60 s, 120 s, 180 s, and 240 s) provided the same reduction in infection rates. Therefore, 60 s was confirmed as the minimum exposure time to achieve a 99.9999% or 6 Log reduction in MHV-3 coronavirus infection rates in the PFF2 samples tested in the device.

Conclusions

We conclude that the assessed UV-C chamber for the inactivation of MHV-3 coronavirus in N95/PFF2 standard masks can be a promising tool for effective and rapid disinfection of coronaviruses, including SARS-CoV-2 virus.