Red LED Light Research Articles

Protein and lysine improvement harnessed by a signal chain of red light-emitting diode light in Chlorella pyrenoidosa

Microalgae are emerging as a novel single-cell protein source that can substitute traditional plant protein feeds. In this investigation, lysine and protein accumulation in Chlorella pyrenoidosa were significantly enhanced under red light-emitting diode light, addressing challenge of limiting amino acid in plant proteins. The study employed targeted metabolomics, HPLC, and qRT-PCR to validate the light-induced pathway triggering lysine biosynthesis. Specifically, the pathway involves Ca2+-CaM as an intermediary in signal transduction, which directly inhibits PEPC activity. This inhibition directs a significant carbon flux towards central carbon metabolism, resulting in increased pyruvate levels—a critical precursor for lysine biosynthesis via the diaminopimelate pathway. Ultimately, the content of protein and lysine under red light increased by 36.02 % and 99.56 %, respectively, compared to those under white light. These findings provide a novel orientation for the precise regulation of lysine accumulation in microalgae, and moreover lay a solid theoretical foundation for producing microalgal proteins.

Effects of photodynamic therapy using bisdemethoxycurcumin combined with melatonin or acetyl-melatonin on C. Albicans

The current study aims to explore the efficacy of antifungal photodynamic therapy (PDT) on C. albicans biofilms by combining photosensitizers, bisdemethoxycurcumin (BDMC), and melatonin (MLT) or acetyl-melatonin (AcO-MLT). Additionally, the relationship between different types of reactive oxygen species and PDT’s antifungal efficacy was investigated. BDMC, MLT and AcO-MLT were applied, alone and in combination, to 48-hour C. albicans biofilm cultures (n = 6/group). Blue and red LED light (250 mW/cm2 with 37.5 J/cm2 for single or 75 J/cm2 for dual photosensitizer groups) were used to irradiate BDMC groups and MLT/AcO-MLT groups, respectively. For combination groups, blue LEDs and subsequently red LEDs were used. Drop plate assays were performed at 0, 1 and 6 h post-treatment. Colony forming units (CFUs) were then counted after 48 h. Hydroxyl radicals and singlet oxygen were measured using fluorescence spectroscopy and electron spin resonance (ESR) spectroscopy. Additionally, cell cytotoxicity was tested on human oral keratinocytes. Significant CFU reductions were observed with combinations 20 µM BDMC + 20 µM AcO-MLT and 60 µM BDMC + 20 µM MLT at 0 and 1 h post-treatment, respectively. Singlet oxygen production increased with the addition of MLT/AcO-MLT and had moderate-substantial correlations with inhibition at all times. Hydroxyl radical production was not significantly different from the control. Additionally, BDMC exhibited subtle cytotoxicity on human oral keratinocytes. PDT using BDMC + MLT or AcO-MLT, with blue and red LED light, effectively inhibits C. albicans biofilm through singlet oxygen generation. Melatonin acts as a photosensitizer in PDT to inhibit fungal infection.

Low-energy red light-emitting diode irradiation enhances osteogenic differentiation of periodontal ligament stem cells by regulating miR-146a-5p.

The study aimed to investigate the role of miR-146a-5p in osteogenesis of hPDLSCs irradiated with low-energy red LEDs. After irradiation with 5 J/cm2 red LED, miR-146a-5p expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR), and osteogenic markers expression was determined by RT-qPCR and Western blotting. Alkaline phosphatase (ALP) activity was assessed by ALP staining, and mineralization was assessed by Alizarin Red staining, respectively. Lentiviral vectors were designed to regulate miR-146a-5p expression. Dual-luciferase reporter assay was performed to confirm the targeted relationship between miR-146a-5p and MAPK1. Short hairpin RNA (shRNA) was used to regulate MAPK1 expression. RT-qPCR and western blotting revealed that 5 J/cm2 irradiation elevated the levels of the osteogenic markers osterix (OSX) and bone sialoprotein (BSP) in hPDLSCs. miR-146a-5p is downregulated in hPDLSCs under the low-energy red LED light irradiation. miR-146a-5p underexpression markedly promoted the osteogenic potential of hPDLSCs. miR-146a-5p targeted MAPK1. 5 J/cm2 red LED irradiation rescued the inhibitory effects of upregulated miR-146a-5p on osteogenic differentiation, and the positive influence of red LED irradiation could be reversed by downregulated MAPK1. These findings confirm that miR-146a-5p is involved in the effect of LED irradiation on the osteogenic differentiation of hPDLSCs by targeting MAPK1. Red LED irradiation may be a potential clinical adjunct therapy for periodontal regeneration.

In Vivo Lifetime Imaging of the Internal O2 Dynamics in Corals with near-Infrared-Emitting Sensor Nanoparticles.

Mapping of O2 with luminescent sensors within intact animals is challenging due to attenuation of excitation and emission light caused by tissue absorption and scattering as well as interfering background fluorescence. Here we show the application of luminescent O2 sensor nanoparticles (∼50-70 nm) composed of the O2 indicator platinum(II) tetra(4-fluoro)phenyltetrabenzoporphyrin (PtTPTBPF) immobilized in poly(methyl methacrylate-co-methacrylic acid) (PMMA-MA). We injected the sensor nanoparticles into the gastrovascular system of intact colony fractions of reef-building tropical corals that harbor photosynthetic microalgae in their tissues. The sensor nanoparticles are excited by red LED light (617 nm) and emit in the near-infrared (780 nm), which enhances the transmission of excitation and emission light through biological materials. This enabled us to map the internal O2 concentration via time-domain luminescence lifetime imaging through the outer tissue layers across several coral polyps in flowing seawater. After injection, nanoparticles dispersed within the coral tissue for several hours. While luminescence intensity imaging showed some local aggregation of sensor particles, lifetime imaging showed a more homogeneous O2 distribution across a larger area of the coral colony. Local stimulation of symbiont photosynthesis in corals induced oxygenation of illuminated tissue areas and formation of lateral O2 gradients toward surrounding respiring tissues, which were dissipated rapidly after the onset of darkness. Such measurements are key to improving our understanding of how corals regulate their internal chemical microenvironment and metabolic activity, and how they are affected by environmental stress such as ocean warming, acidification, and deoxygenation. Our experimental approach can also be adapted for in vivo O2 imaging in other natural systems such as biofilms, plant and animal tissues, as well as in organoids and other cell constructs, where imaging internal O2 conditions are relevant and challenging due to high optical density and background fluorescence.

Synthesis and Spectroscopic Study of a Homogenous Bimetallic Os(II) Complex as a New Gastric Cancer Photosensitizer.

A homogenous dinuclear Os(II) complex bisOs was synthesized and fully characterized. The electrochemical cyclic voltammetry study, and density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were performed to investigate the electronic property. bisOs showed an obvious interaction with lipase and BSA, and can generate singlet oxygen under blue and red LED light irradiation, with a singlet oxygen quantum yield (ФΔ) of 0.36 in comparison to that of [Ru(bpy)3]Cl2 in acetonitrile. bisOs exhibited moderate to great photocytotoxicity against HGC-27 human gastric cancer cells under blue LED light irradiation, giving the IC50 value as low as 1.83 µM (PI value is 9.7), while was almost non-cytotoxic in the dark. The cellular singlet oxygen detection in HGC-27 cancer cells exhibited a concentration-dependent manner, and cell uptake of bisOs in A549 cells was as high as 120 ng/106 cells, subcellular colocalization study indicated that bisOs was not accumulated in nucleus, and less likely to target mitochondria. This work provides a new example of dinuclear osmium complex as potential photosensitizer candidate for gastric treatment.

Design, construction, and testing of generation of electric energy using microbial fuel cell

A microbial fuel cell (MFC) is a bio-electrochemical system that converts chemical energy from organic compounds/renewable energy sources to electrical energy/bio-electrical energy through microbial catalysis at the anode under anaerobic conditions. The process is becoming an attractive and alternative methodology for the generation of electricity. The scope of this paper was to design, construct, and test microbial fuel cells that source their fuel from organic waste, using microbial fuel cells to power LED lights. The research concluded that microbial fuel is a prospective energy source for future electricity that can be produced and used by all consumers. Single Chamber Microbial fuel cells were set up using material readily available around i.e. the slurry and, in the market, i.e. the other materials, in batches. The studies showed that the single chamber MFC can produce a maximum voltage of over 500mV and can last for a minimum of two and half months. Out of the 30 MFCs produced 18 of them which produce stable and progressive voltage were connected in series in the frame. The whole setup successfully powered five red LED lights. This shows that more of the MFCs set up can produce more electricity such as that can power a control system.

Effect of 660-nm LED photobiomodulation on the proliferation and chondrogenesis of meniscus-derived stem cells (MeSCs)

Meniscus-derived stem cells (MeSCs), a unique type of MSC, have outstanding advantages in meniscal cytotherapy and tissue engineering, but the effects and molecular mechanisms of PBM on MeSCs are still unclear. We used 660-nm LED light with different energy densities to irradiate six human MeSC samples and tested their proliferation rate via cell counting, chondrogenic differentiation capacity via the DMMB assay, mitochondrial activity via the MTT assay, and gene expression via qPCR. The proliferation ability, chondrogenic capacity and mitochondrial activity of the 18 J/cm2 group were greater than those of the 4 J/cm2 and control groups. The mRNA expression levels of Akt, PI3K, TGF-β3, Ki67 and Notch-1 in the 18 J/cm2 group were greater than those in the other groups in most samples. After chondrogenic induction, the expression of Col2A1, Sox9 and Aggrecan in the 18 J/cm2 group was significantly greater than that in the 4 J/cm2 and control groups in most of the samples. The variation in the MTT values and Src, PI3K, Akt, mTOR and GSK3β levels decreased with time. The results showed that 660-nm LED red light promoted proliferation and chondrogenic differentiation and affected the gene expression of MeSCs, and the effects on gene expression and mitochondrial activity decreased with time.

Enhancing the phytoremediation efficiency of Bacopa monnieri (L.) Wettst. using LED lights: a sustainable approach for heavy metal pollution control.

In this study, the impacts of LEDs on the phytoremediation of arsenic (As) and mercury (Hg) by Bacopa monnieri (L.) Wettst. were investigated, along with the examination of the biochemical characteristics of plants exposed to metal-induced toxicity. In vitro multiple and rapid plant propagations were successfully achieved by adding 1.0mg/L 6-Benzyl amino purine (BAP) to the Murashige and Skoog (MS) basal salt and vitamin culture medium. For plant-based remediation experiments, different concentrations of As (0-1.0mg/L) and Hg (0-0.2mg/L) were added to the water environment, and trials were conducted for four different application periods (1-21days). White, red, and blue LEDs, as well as white fluorescent light, were preferred as the light environment. The results revealed that LED lights were more effective for heavy metal accumulation, with red LED light significantly enhancing the plant's phytoremediation capacity compared to other LED applications. Moreover, when examining biochemical stress parameters such as levels of photosynthetic pigments, protein concentrations, and lipid peroxidation, plants under red LED light showed better results. Generally, the lowest results were obtained under white fluorescent light. These findings contribute to phytoremediation studies by highlighting the integration of LED lights, thereby enabling the development of a more effective, cost-efficient, and environmentally sustainable remediation system compared to other treatment methods.

Combining red photobiomodulation therapy with polydioxanone threads for wrinkle reduction in the glabella region: A randomized, controlled, double-blind clinical trial.

The combination of polydioxanone (PDO) threads with other technologies has garnered significant interest for rejuvenation purposes. Photobiomodulation (PBM) has the potential to improve patient comfort and recovery after minimally invasive rejuvenation protocols and also contribute to the overall efficacy of these procedures, fostering an integrative approach to cutaneous rejuvenation. The objective os this work was to investigate concurrent application of PDO threads and red LED PBM on glabellar static wrinkles, in a parallel randomized sham-controlled trial. Forty individuals with Glogau aging classification levels 3 and 4, static glabellar wrinkles, and no significant comorbidities received PDO threads applied along glabellar line. Effective PBM group received 1.35 J and 630 nm red LED light punctually along threads, twice weekly for nine sessions over 30 days. The outcome measures were swelling assessment, dermal thickness and PDO thread degradation via linear ultrasound. No swelling was detected 24 h post-PDO thread application, hindering PBM effect assessment. PDO threads induced dermal thickening; no added effect with PBM. No significant difference in thread hydrolysis between groups, though some ultrasound records inconclusive on thread presence. The absence of swelling may stem from various factors, including the timing of post-procedure swelling assessment, operator proficiency in thread application, and procedural characteristics. No evidence supports the notion that PBM augments dermal thickening, however other light parameters should be studied. Insufficient data to demonstrate PBM's effectiveness in controlling post-procedure swelling. Combination of PBM with PDO thread application doesn't enhance dermal thickening, nor accelerate thread degradation at the parameters used here.

Effects of photobiomodulation on colon cancer cell line HT29 according to mitochondria

Background/AimAlthough photobiomodulation therapy (PBMt) is available to alleviate post-operative side effects of malignant diseases, its application is still controversial due to some potential of cancer recurrence and occurrence of a secondary malignancy. We investigated effect of PBMt on mitochondrial function in HT29 colon cancer cells. MethodsHT29 cell proliferation was determined with MTT assay after PBMt. Immunofluorescent staining was performed to determine mitochondrial biogenesis and reactive oxygen species (ROS). Mitochondrial membrane potential was measured with Mitotracker. Western blotting was executed to determine expression of fission, fusion, UCP2, and cyclin B1 and D1 proteins. In vivo study was performed by subcutaneously inoculating cancer cells into nude mice and immunohistochemistry was done to determine expression of FIS1, MFN2, UCP2, and p-AKT. ResultsThe proliferation and migration of HT29 cells reached maximum with PBMt (670 nm, light emitting diode, LED) at 2.0 J/cm2 compared to control (P < 0.05) with more expression of cyclin B1 and cyclin D1 (P < 0.05). Immunofluorescent staining showed that ROS and mitochondrial membrane potential were enhanced after PBMt compared to control. ATP synthesis of mitochondria was also higher in the PBMt group than in the control (P < 0.05). Expression levels of fission and fusion proteins were significantly increased in the PBMt group than in the control (P < 0.05). Electron microscopy revealed that the percentage of mitochondria showing fission was not significantly different between the two groups. Oncometabolites including D-2-hydoxyglutamate in the supernatant of cell culture were higher in the PBMt group than in the control with increased UCP2 expression (P < 0.05). Both tumor size and weight of xenograft in nude mice model were bigger and heavier in the PBMt group than in the control (P < 0.05). Immunohistologically, mitochondrial biogenesis proteins UCP2 and p-AKT in xenograft of nude mice were expressed more in the PBMt group than in the control (P < 0.05). ConclusionsTreatment with PBM using red light LED may induce proliferation and progression of HT29 cancer cells by increasing mitochondrial activity and fission.

An artificial neuronal network coupled with a genetic algorithm to optimise the production of unsaturated fatty acids in Parachlorella kessleri

In this study, an Artificial Neural Network-Genetic Algorithm (ANN-GA) approach was successfully applied to optimise the physicochemical factors influencing the synthesis of unsaturated fatty acids (UFAs) in the microalgae P. kessleri UCM 001. The optimized model recommended specific cultivation conditions, including glucose at 29 g/L, NaNO3 at 2.4 g/L, K2HPO4 at 0.4 g/L, red LED light, an intensity of 1000 lx, and an 8:16-h light-dark cycle. Through ANN-GA optimisation, a remarkable 66.79% increase in UFAs production in P. kessleri UCM 001 was achieved, compared to previous studies. This underscores the potential of this technology for enhancing valuable lipid production. Sequential variations in the application of physicochemical factors during microalgae culture under mixotrophic conditions, as optimized by ANN-GA, induced alterations in UFAs production and composition in P. kessleri UCM 001. This suggests the feasibility of tailoring the lipid profile of microalgae to obtain specific lipids for diverse industrial applications. The microalgae were isolated from a high-mountain lake in Colombia, highlighting their adaptation to extreme conditions. This underscores their potential for sustainable lipid and biomaterial production. This study demonstrates the effectiveness of using ANN-GA technology to optimise UFAs production in microalgae, offering a promising avenue for obtaining valuable lipids. The microalgae's unique origin in a high-mountain environment in Colombia emphasises the importance of exploring and harnessing microbial resources in distinctive geographical regions for biotechnological applications.

Increased CD56 expression after photodynamic therapy indicates an increased natural killer cell count following early photodynamic therapy for cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (cSCC) is the second most common type of skin cancer. Photodynamic therapy (PDT) is a promising therapeutic method for managing cSCC due to its proven ability to target specific areas over time and its low risk of side effects. PDT may cause tissue damage and vascular shutdown, and may regulate local immunological responses. The present study aimed to investigate and compare the early lymphocyte modifications before and after PDT for SCC. A total of 10 patients with SCC were identified by pathological investigation. Initially, all wounds were treated with 20% aminolevulinic acid (ALA)-PDT as the initial stage in the therapeutic procedure. The wounds were treated by exposing them to red LED light with a wavelength of 635 nm, an energy density of 100 J/cm2 and an intensity of 80 mW/cm2. The tumor tissue was surgically removed 24 h later, and another round of PDT therapy was administered. Immunohistochemistry for CD3 and CD56 was conducted on the wound tissue post-surgery. If the wound showed granulation, necrosis or secretion, debridement was added to the therapy. All patients were monitored for 0.6-1.0 year post-treatment. ALA-PDT combination surgery fully controlled the tumor tissue in all 10 patients. The immunohistochemical analysis of the wound tissues showed that the expression of CD56 increased, while the expression of CD3 was not different after photodynamic therapy. These results also indirectly indicated that the overall count of NK cells in the 10 patients increased, nevertheless, there was no alteration in the T lymphocyte count. In conclusion, the ALA-PDT combination surgical therapy for cSCC demonstrates favorable results. An increase in CD56 expression may be a mechanism for the effective treatment of cSCC with PDT.

VEHICAL ACCIDENT PREVENTION SYSTEM FOR MOUNTAIN ROADS

Vehicle accident prevention system can be a major step in accident safety on mountain roads. In past 100s of accident and death on mountain roads, some even fall from the cliff which are not traced after that have been noticed. Such accidents not only cause loss of human life but also major loss financially not just to the individual but also the government. Mountain roads are narrow and any such accidents can force it to be closed for hours which can be a huge issue. This project addresses the pressing issue of mountain road safety through the deployment of two strategically positioned ultrasonic sensors in U curves. The primary objective is to detect oncoming vehicles, precisely measure distances, and promptly activate warnings on the opposite side. By leveraging real-time data and proactive measures, the system aims to significantly reduce accidents in challenging terrains. The integration of red LED lights and a buzzer enhances visibility and auditory awareness. This innovative approach reflects a crucial step forward in accident prevention, particularly in mountainous regions, where traditional safety measures fall short.

Halogenated BOIMPYs and Their Efficiency in Photodynamic Therapy

BOIMPY (bis‐ (borondifluoride)‐8‐imidazodipyrromethene) photosensitizers were developed for imaging‐guided photodynamic therapy (PDT). The introduction of heavy atoms (Br and I) to the b‐positions of BOIMPY combined with the twisted structure of the molecule was the strategy to enhance the intersystem crossing process of the BOIMPYs and reduce intermolecular π−π interactions of BOIMPY core. To clarify the electronic features of BOIMPY derivatives, their optical properties were studied using UV‐vis absorption, fluorescence spectroscopy, electrochemistry, and density functional theory (DFT) computing. The halogenated BOIMPYs exhibited a high absorption coefficient with high singlet oxygen generation ability (Φ∆ = 0.46 and 0.94 for brominated and iodinated BOIMPY, respectively). More significantly, an in vitro investigation showed that all derivatives displayed vivid fluorescence in cancer cells and that the halogenated BOIMPYs increased the effectiveness of tumor inhibition upon exposure to 660 nm red LED light radiation. The half‐maximal inhibitory concentrations for the iodinated and brominated BOIMPYs were 2.14 µM and 14.78 µM, respectively. Consequently, iodinated BOIMPY has been shown to represent a new class of photosensitizers with potential use in imaging‐guided photodynamic therapy.

Red LED light affects the physicochemical responses of strawberries during storage

This study aimed to evaluate the effect of the storage of strawberries under LED lights on ‘Albion’ strawberry quality. The treatments were applied as follows; (1) storage under continuous blue, red, and ultraviolet-A (UVA) LED light, (2) storage in the dark conditions (control), and (3) storage in the dark conditions after 1 h UVA (UVAh) LED lighting. Strawberries were stored at a temperature of 4±1oC with 85-90% relative humidity for 10 days. In the study, analyses were conducted on the total anthocyanin content, color (L*, hue angle, redness index), total soluble solids (TSS), fructose, glucose, total sugar content, titratable acidity (TA), fruit firmness (N), and weight loss at the start of the experiment and at 2-day intervals during storage. According to the results, the storage of strawberries under continuous red-LED light was successful in improving the anthocyanin and TSS contents, while preserving fruit firmness and reducing weight loss. Moreover, UVA treatment was effective in maintaining the L*, a*, and b* color values, whereas UVAh was effective on the hue angle and redness index. Furthermore, UVAh treatment caused a decrease in the glucose, fructose, and total sugar content and, in the titratable acidity of the strawberries.

Unveiling the Cultivation of Nostoc sp. under Controlled Laboratory Conditions.

Cyanobacteria, photoautotrophic Gram-negative bacteria, play a crucial role in aquatic and terrestrial environments, contributing significantly to fundamental ecological processes and displaying potential for various biotechnological applications. It is, therefore, critical to identify viable strains for aquaculture and establish accurate culture parameters to ensure an extensive biomass supply for biotechnology purposes. This study aims to establish optimal laboratory batch culture conditions for Nostoc 136, sourced from Alga2O, Coimbra, Portugal. Preliminary investigations were conducted to identify the optimal culture parameters and to perform biomass analysis, including protein and pigment content. The highest growth was achieved with an initial inoculum concentration of 1 g.L-1, using modified BG11 supplemented with nitrogen, resulting in a Specific Growth Rate (SGR) of 0.232 ± 0.017 μ.day-1. When exposed to white, red, and blue LED light, the most favourable growth occurred under a combination of white and red LED light exhibiting an SGR of 0.142 ± 0.020 μ.day-1. The protein content was determined to be 10.80 ± 2.09%. Regarding the pigments, phycocyanin reached a concentration of 200.29 ± 30.07 µg.mL-1, phycoerythrin 148.29 ± 26.74 µg.mL-1, and allophycocyanin 10.69 ± 6.07 µg.mL-1. This study underscores the influence of light and nutrient supplementation on the growth of the Nostoc biomass.

Effects of light-emitting diodes on the morphology and accumulation of glucosinolates, carotenoids and phenolic acids in red kale sprouts

Kale (Brassica oleracea var. acephala) has gained popularity as a nutritious and phytochemical-rich vegetable. This study has investigated the effects of three LED treatments (white, blue, and red) on the accumulation of secondary metabolites in kale sprouts. Ten DAS, the kale sprouts were harvested, and growth measurements were measured. Furthermore, selected sprouts were stored at -80 °C for further biochemical analysis, namely, phenolic acids, glucosinolates, and carotenoids. Sprouts irradiated with red LED light showed the best SL, RT, and FW values. For total GSLs, we found that kale sprouts irradiated with white LED lights showed the best results (41.59±0.41 μmol/g DW). Among the aliphatic GSLs, we found that progoitrin presented the best results under blue LED light (17.93±0.49 µmol/g DW), and among the indolic GSLs, glucobrassicin showed the best results under white and red LED light. The highest concentration of total carotenoids was found in kale sprouts under white LED light exposure (3341.27±206.96 μg/g DW). Individually, β-carotene was observed in high concentration under white LED light (1935.13±87.21 μg/g DW). Among the PAs, chlorogenic acid was found in the highest concentration in the treatments under white LED light (45.78±0.73 µg/g DW). In general, kale sprouts irradiated with white LED light showed high contents of GSLs, carotenoids, and PAs. Regarding morphological characteristics, kale sprouts under red LED light showed the most promise. This research offers a valuable approach to enhancing the phytochemicals found in kale sprouting.

Effectiveness of light-emitting diodes for arsenic and mercury accumulation by Ceratophyllum demersum L.: An innovative advancement in phytoremediation technology

Light Emitting Diodes (LEDs) have emerged as a tool with great potential in the field of phytoremediation, offering a novel approach to enhance the efficiency of plant-based remediation techniques. In this work investigated the influence of LEDs on the phytoremediation of arsenic (As) and mercury (Hg) by Ceratophyllum demersum L., propagated using tissue culture methods. In addition, the biochemical properties of the plants exposed to metal toxicity were examined. Phytoremediation experiments employed concentrations of As (0.01–1.0 mg/L) and Hg (0.002–0.2 mg/L), with application periods set at 1, 7, 14, and 21 days. In addition to white, red and blue LEDs, white fluorescent light was used for control purposes in the investigations. A positive correlation was observed between higher metal concentrations, extended exposure times, and increased metal accumulation in the plants. Red LED light yielded the highest level of heavy metal accumulation, while white fluorescent light resulted in the lowest accumulation level. Examination of the biochemical parameters of the plants, including photosynthetic pigment levels, protein quantities, and lipid peroxidation, revealed a pronouncedly enhanced performance in specimens subjected to red and blue LED illumination, surpassing outcomes observed in other light treatments. The findings of this study introduce innovative avenues for the effective utilization of red and blue LED lights in the realm of phytoremediation research. Thus, the interaction between LEDs, tissue culture, and the phytoremediation process could lead to synergistic effects that contribute to more effective and sustainable remediation strategies.

Therapeutic and fluorescence evaluation of 20% 5-aminolevulinic acid-mediated photodynamic therapy in actinic keratosis

BackgroundActinic keratosis (AK) is a precancerous lesion that occurs in areas that are chronically exposed to sunlight and has the potential to develop into invasive cutaneous squamous cell carcinoma (cSCC). We investigated the efficacy of 20 % 5-aminolevulinic acid-photodynamic therapy (ALA-PDT) with LED red light for the treatment of AK in Chinese patients by examining changes in dermoscopic features, histopathology and fluorescence after treatment. MethodsTwenty-eight patients with fourty-six AK lesions from March 2022 to September 2023 were treated with 20 % ALA, and 3 h later, they were irradiated with LED red light (80–100 mW/cm2) for 20 min. A session of 20 % ALA-PDT was performed once a week for three consecutive weeks, and the dermoscopic, histopathological, fluorescent and photoaging outcomes were measured one week after the treatment. ResultsOne week after ALA-PDT, complete remission (CR) was reached in 53.6 % of patients. The CR of Grade I AK lesions was 100 %, that of Grade II lesions was 71.4 %, and that of Grade III lesions was 38.1 %. There was a significant improvement in the dermoscopic features, epidermal thickness and fluorescence of the AK lesions. The presence of red fluorescence decreased, and there was an association between CR and post-PDT fluorescence intensity. ALA-PDT also exhibited efficacy in treating photoaging, including fine lines, sallowness, mottled pigmentation, erythema, and telangiectasias, and improved the global score for photoaging. There were no serious adverse effects during or after ALA-PDT, and 82.1 % of the patients were satisfied with the treatment. ConclusionAK lesions can be safely and effectively treated with 20 % ALA-PDT with LED red light, which also alleviates photoaging in Chinese patients, including those with multiple AKs. This study highlights the possibility that fluorescence could be used to diagnose AK with peripheral field cancerization and evaluate the efficacy of ALA-PDT.

Modified Painless Photodynamic Therapy for Actinic Keratosis in China

SignificanceAminolevulinic acid photodynamic therapy (ALA-PDT) is an effective treatment for actinic keratosis (AK). However, the pain during illumination usually caused patient to discontinue PDT treatment and resulted lower efficacy. Previous study showed modified painless PDT (M-PDT) with short ALA incubation time and longer irradiation time can reduce pain and preserve the efficacy. If M-PDT worked in AK still need to investigate. ApproachA splie-face controlled clinical study was conducted. Eleven patients with facial AK received C-PDT (conventional PDT) on the left and M-PDT in the contralateral area. The left area was illuminated by a red LED light (a total light dose of 140 J/cm2) after applying the ALA cream for 3 hours; the other had illumination for a total light dose of 288 J/cm2 after applying the ALA cream for 0.5 hours. The primary endpoint was the lesion clearance rate at 1 month. Secondary endpoints included pain scores, the incidence of adverse events, and cosmetic outcomes. ResultsAt one month following 3 treatments, the lesion clearance rate of M-PDT was non-inferior to that of C-PDT (93.1% vs. 86.4%, respectively. The lesion clearance rate of M-PDT to reach 100% clearance earlier than C-PDT for grade I lesions and higher clearance rates for grade III lesions. Moreover, the pain score during illumination was significantly lower for M-PDT than for C-PDT (P < 0.01). Regarding photoaging, the Global Subjective Skin Aging Assessment (GS2A2) score showed that the total and atrophy scores of C-PDT and M-PDT were significantly improved, and M-PDT also reduced discoloration. There was no significant difference in adverse reactions between C-PDT and M-PDT. ConclusionsM-PDT is non-inferior to C-PDT in terms of efficacy for treating AK, resulting in much lower pain scores.