UV Lamp Research Articles

A Review on Formulation and Evaluation of Herbal Face Serum

Facial wrinkles and skin aging are often caused by sun damage and UV rays, and there are currently no effective methods to slow down the aging process. Aloe Vera, glycerin, and honeybee venom are key ingredients in a concentrated face serum that helps improve skin health. Aloe Vera provides quick cosmetic benefits and also has psychological effects. The serum is easily absorbed and can penetrate deeper layers of the skin. Aloe Vera is known for treating skin issues like sunburns, minor cuts, and insect bites, and it has healing, anti-inflammatory, antibacterial, and antifungal properties. Bee venom, a toxin produced by bees, is believed to help improve blood flow and increase collagen production. The face serum was tested for its quality, including pH, consistency, and size of the droplets. Stability tests showed that the serum maintained its appearance, texture, and consistency without any changesg

Microbial Contamination and Sterilization Methods in an Air Circulation-Type Geothermal Ventilation System

A simulated system was created to evaluate an air circulation-type geothermal ventilation system, focusing on measuring microbial contamination levels on the surface of the heat exchange unit. Additionally, this study examined sterilization methods using UV lamps on the surface of the heat exchanger. The fungal concentration on the surface of the heat exchanger showed a tendency to increase over time. Although direct comparison is challenging due to the varying concentrations of outdoor air fungi at different measurement times, the surface fungal concentration was highest at a minimum airflow rate of 150 m3/h compared to other conditions. However, since the adhesion of contaminants from outdoor air to the surface of the heat exchanger is influenced not only by airflow but also by outdoor temperature and relative humidity conditions, future research needs to consider these factors. According to the ATP measurement results, microbial contamination was evaluated as “slightly dirty” after 24 h and “dirty” after 48 h of operating the experimental apparatus. Therefore, it is advisable to clean the internal surfaces of the geothermal ventilation system every 1–2 days. The results of the sterilization experiments using UV lamps indicated that irradiation for approximately 30 min inactivated 94.5%-to-96.1% of microorganisms derived from outdoor air. However, since the sterilization dose varies depending on the type of microorganism, it is necessary to determine the optimal irradiation time based on the target microorganisms and the UV lamp’s irradiation intensity.

The Anti-Elixir Triad: Non-Synced Circadian Rhythm, Gut Dysbiosis and Telomeric Damage

Aging is an inevitable life process which is accelerated by lifestyle and environmental factors. It is an irreversible accretion of molecular and cellular damage associated with changes in the body composition and deterioration in physiological functions. Each cell (other than stem cells), reaches the limit of its ability to replicate, known as cellular or replicative senescence and consequently, the organs lose their physiological functions resulting in overall impairment. Other factors that promote aging include smoking, alcohol, UV rays, sleep habits, food, stress, sedentary life style and genetic abnormalities. These stress factors, can alter our endogenous clock (the circadian rhythm) and the microbial commensals. As a result of effect of these stressors, the microorganisms that generally support human physiological processes become baleful. The disturbance of natural physiology instigates many age-related pathologies, such as cardiovascular diseases, chronic obstructive pulmonary disorder, cerebrovascular diseases, opportunistic infections, high blood pressure, cancer, diabetes, kidney diseases, dementia, and Alzheimer’s disease. The present review covers the three most essential processes of the circadian clock; the circadian gene mechanism and regulation, the mitotic clock (which plays a vital role in the telomere’s attrition) and gut microbiota and their metabolome that drive aging and lead to age-related pathologies. In conclusion, maintaining a synchronized circadian rhythm, a healthy gut microbiome and telomere integrity is essential for mitigating the effects of aging and promoting longevity. The interplay among these factors underscores the importance of lifestyle choices in enhancing overall health and lifespan.

The Identification of Six Estrogen Preparations by Combining Thin-Layer Chromatography with Micro-Raman Imaging Spectroscopy

A method for identifying six estrogen preparations by thin-layer chromatography combined with Raman imaging microscopy (TLC-RIM) was established. An appropriate pretreatment method was adopted to extract and purify the six estrogen preparations. After that, each estrogen extraction solution was spotted on a thin-layer chromatography plate. Estriol (E3), estradiol (E2), estradiol valerate (EV), estradiol benzoate (EB), nilestriol (CEE), and ethinylestradiol (EE2) were separated by TLC, and their Rf value and localization were determined under a UV lamp at 254 nm, followed by the in situ enrichment of the drug component. Using a 532 nm laser as the light source, the Raman scattering spectrum of the component was directly collected by micro-Raman imaging. The Rf values after TLC separation of the six estrogens and their Raman spectra can, respectively, reflect differences in polarity and structure, and they are not affected by the excipients of preparation. The detection limits of the six estrogens are 0.636, 1.00, 0.687, 0.497, 0.649, and 0.626 mg/mL. Based on the intensity of the minimum characteristic peak, the stability results within 40 min showed that the RSD of each substance is 1.34, 2.06, 1.65, 3.99, 1.16, and 2.71%, respectively. This method has strong specificity, good stability, and high sensitivity, and it can provide a new reference for improving the identification standards of estrogen preparations.

Adjustable Emission Color by Gadolinium Tungstate Phosphor for Multiple Applications

Crystalline monoclinic structure Gd2(WO4)3 phosphors were prepared by calcining a co-precipitated precursor at 800°C. The XRD patterns exhibited strong signals at the (-221) and (023) planes. The UV-vis absorption spectrum showed strong absorbance in the UV range, with an estimated bandgap energy of about 4 eV. When excited the synthesized phosphors emitted green (Tb3+), red (Eu3+), yellow (Dy3+), and reddish orange (Sm3+), respectively. Utilizing these luminescent properties, flexible composite sheets were fabricated by mixing the phosphors with PDMS. When applied to UV-LED chips. The composites could be molded into various shapes figures. Under normal light, the composites appeared white, but under UV light, they displayed distinct colors, demonstrating their potential for anti-counterfeiting applications. Additionally, when the synthesized phosphor powder was sprinkled onto a glass substrate with fingerprints and illuminated with a UV lamp, the unique features of the fingerprints were clearly visible, indicating potential use in forensic fingerprint analysis.

Thyroid and growth hormone endocrine disruption and mechanisms of homosalate and octisalate using wild-type, thrαa-/-, and dre-miR-499-/- zebrafish embryo/larvae

Homosalate (HS) and octisalate (OS), which are used in sunscreen for the purpose of blocking ultraviolet rays, are frequently detected in water environment. Although effects on estrogens and androgens have been reported, studies on thyroid and growth hormone endocrine disruption are limited. In the present study, larval mortality was compared in wild-type and two knockout fish (thyroid hormone receptor alpha a knockout (thrαa-/-) and dre-miR-499 knockout (dre-miR-499-/-)) after 96 h of exposure to HS and OS (0, 0.003, 0.03, 0.3, 3, 30 and 300 µg/L). To investigate the mechanisms of thyroid and growth hormone endocrine disruption, we measured the levels of triiodothyronine (T3), thyroxine (T4), thyroid stimulating hormone (TSH), growth hormone (GH), and insulin-like growth factor-1 (IGF-1), and the regulation of representative genes related to the hypothalamus-pituitary-thyroid (HPT) and GH/IGF axis in wild-type zebrafish exposed to target chemicals. The significantly lower larval survival rate of thrαa-/- and dre-miR-499-/- fish exposed to 300 μg/L of HS and OS suggest that thyroid hormone receptors and dre-miR-499 play a crucial role in the toxic effects of HS and OS. The finding of a significant increase in T3 and T4 in zebrafish larvae exposed to HS and OS supports a significant decrease in the crh gene. The reduction of GH and IGF-1 in fish exposed to HS and OS is well supported by the regulation of genes involved in the GH/IGF axis. Our observations suggest that exposure to HS and OS affects not only thyroid hormone receptors and their associated miRNAs, but also the feedback routes of HPT and GH/IGF axes, ultimately leading to growth reduction.

Community Empowerment in Stunting Prevention: Implementation of the UBaMa Method (Ultra Violet Rays and Baby Massage)

Babies are an age group that is vulnerable to stunting. The incidence of stunting in Ngariboyo District in 2022 was 185 (13.14%) children under five, the highest occurred in Mojopurno Village, which was 49 (19.91%) children under five. The purpose of this activity is to improve the understanding, attitude and behavior of baby mothers in stimulation with the UBaMa method. The method carried out is to conduct a pre-test for baby mothers, followed by providing explanations and training on the UBaMa method. After that, the baby's mother was asked to carry out UBaMa at home, evaluated at the second meeting and so on until the fourth meeting. After the fourth meeting, a post-test was carried out. The results achieved were an improvement in the skills of mothers under five to do stimulation with the UBaMa Method with a proficiency of 68%. Knowledge Improvement with pre-test 49 and post-test 83.75. The UBaMa Stimulation Method (Ultra Violet and Baby Massage) can improve the growth and development of babies. It is recommended that the baby's mother periodically stimulate UBaMa at least 3 times a week to increase breast milk production so that it can be used to prevent stunting.

Efficient Degradation of Methyl Violet 10B Dye by Different Light Sources using Boron-doped TiO2-ZnO Photocatalyst

Boron-doped TiO2-ZnO nanocomposite was prepared by sonochemically using boron trichloride, tetra n-butyl orthotitanate and zinc acetate in appropriate proportion. The as-prepared nanocomposite was successfully characterized by XRD, EDX, SEM and BET techniques The operational factors that affect the rate of photocatalytic degradation of methyl violet 10B present in wastewater were optimized, which include initial dye concentration, catalyst amount, pH level and different light intensities such as incandescent light bulb, UV lamp and sunlight. During sonication under sunlight, it was found that the most effective removal rate achieved was 95% when using 0.02 g of B doped TiO2-ZnO per 100 mL of methyl violet 10B solution. The impact of different dye concentrations on the photocatalytic degradation demonstrated the threshold at which concentrations may be readily eliminated. The most effective pollutant degradation was achieved at 5 ppm. The introduction of oxygen using sonophotocatalysis process into the polluted stream enhanced the photocatalytic breakdown of the pollutants. The photocatalyst can be recycled for four cycles without loss the catalyst stability and the degradation rate obeys first-order kinetics.

Determination of SPF (Sun Protection Factor) Value of Lotion Preparation of Ethanol Extract of Akway Bark (Drymis Piperita Hook F.) of West Papua

Akway bark (Drymis piperita Hook f.) has antioxidant activity. It contains secondary metabolite compounds, one of which is flovonid so that it can be utilized as protection against UV rays and developed into pharmaceutical preparations, namely lotions. The aim of the study was to test the physical stability and determine the SPF value of lotion preparations of ethanol extract of akway bark analyzed in vitro. The test includes the determination of SPF value by UV-vis spectrophotometry method. The absorbance was measured at the wavelength of UV B light (290-320 nm) with an interval of 5 nm; the Mansur formula calculated the results obtained. The test results showed that The results of the stability test showed that the lotion preparation of akway bark extract was stable in organoleptic testing, elution type test, homogeneity test, the stickiness test, spreadability test, pH test, protective power test and the SPF value of lotions with concentrations of 0.5%, 1.0%, 1.5% obtained an average SPF value of 5.20 ± 0.00 in the medium protection category that protected the skin for 52 minutes; 11.52 ± 0.00 maximum protection that protected the skin for 115 minutes; and 5.20 ± 0.00 in the maximum protection category that protected the skin for 115 minutes. 16.00 ± 0.03 ultra protection will protect the skin for 160 minutes from UV B exposure. Thus, it can be concluded that the variation in concentration of akway bark extract affects the SPF value and can potentially be a sunscreen with moderate to ultra protection category.

The substituent effect on pulsed laser beam self-action manifestation in azo-azomethine PMMA composites thin films in visible and near IR ranges

Efficiency of nonlinear optical response was studied for a set of azo-azomethines dyes with substituted electron-withdrawing/donating groups, being embedded in poly(methyl methacrylate) (PMMA) matrix, via self-action effects manifestation of mode-locked Nd:YAG laser single pulses in visible at 532 nm, and in near IR at 1064 nm ranges. Photoinduced variations of refractive index and optical absorption/bleaching are crucially dependent on electron-donating/accepting substituents' properties with |Re(χ(3))| ∼ 10−7 esu and |Im(χ(3))| ∼ 10−9 esu efficiencies correspondingly at moderate laser excitation up to 10 MW/cm2. Incorporation of the azomethine group has provided tendency for fractional self-focusing effect manifestation in visible range against reference Azo dye, while at 1064 nm – self-defocusing one. For some dyes magnitudes of |Re(χ(3))| in near IR range are comparable and even higher than for the corresponding ones at 532 nm due to resonant cascaded three photon excitation into the peak vicinity of π→π∗ transitions of the dyes. It was established linear relationship between second-order hyperpolarizabilities under pulsed and CW laser excitation in visible range, being preliminary irradiated within full spectra of UV lamp for CW laser diagnostics mode. It proofs a suggestion that picosecond range single pulses transfer dyes into the same excited state as full spectrum of a mercury lamp irradiation – conventional tool for the smart molecules’ isomerization. Analysis of the experimental data has shown a high potential for the azo-azomethines dyes doped polymer composites in nonlinear optical applications.

ОЦЕНКА И ПРОГНОЗИРОВАНИЕ РИСКА ПАЦИЕНТСКОГО НОН-КОМПЛАЕНСА В СИСТЕМЕ СПЕЦИАЛИЗИРОВАННОЙ ФАРМАЦЕВТИЧЕСКОЙ ПОМОЩИ НАСЕЛЕНИЮ С ОНКОЛОГИЧЕСКИМИ ЗАБОЛЕВАНИЯМИ

Cardiovascular, oncological and other diseases occupy a significant place in the structure of morbidity and causes of death of the population, the growth of which largely depends on lifestyle and risk factors. Identification of risk factors contributing to the development of cancer is one of the main achievements of epidemiology of the 21st century. Subsequent research helped scientists to build multifactorial algorithms for predicting the risks of cancer and mortality from them, which greatly facilitated the work of practitioners in the field of risk stratification. The above indicates that the research results of many foreign and domestic authors confirm that significant predictors of cancer are risk factors such as old age, pre-existing cancer in blood relatives, smoking, obesity, alcohol, certain types of viral infections, certain chemicals, ionizing radiation, including UV rays of the sun and others. It is known that reducing the influence of risk factors leads to a decrease in morbidity and mortality from cancer. An important condition in the treatment of oncological diseases is the rational and effective use of medicines. Pharmaceutical specialists play an active role in this process. In the treatment of long-term or lifelong diseases, such as cancer, great importance is attached to the process of daily pharmacotherapy, compliance with the rules of adherence to treatment or compliance. Thus, problems with patients performing medical appointments are based on a complex of factors, including psychological and behavioral ones, including patients' adherence to treatment.

Decoding the impact of ageing and environment stressors on skin cell communication.

The integumentary system serves as a crucial protective barrier and is subject to complex signaling pathways that regulate its physiological functions. As the body's first line of defense, the skin is continuously exposed to environmental stressors, necessitating a robust network of signaling molecules to maintain homeostasis. Considering the main cellular components to be keratinocytes, melanocytes, fibroblasts, and fibrous components, collagen of various types, this review explores the intricate signaling mechanisms that govern skin integrity, focusing on key pathways involved in impacts of ageing and environment factors on skin health. The role of growth factors, cytokines, hormones and other molecular mediators in these processes is examined. Specially for women, decrease of estrogen is determinant to alter signaling and to compromise skin structure, especially the dermis. Environmental factors, such as ultraviolet rays and pollution alongside the impact of ageing on signaling pathways, especially TGF-β and proteases (metalloproteinases and cathepsins). Furthermore, with advancing age, the skin's capacity to shelter microbiome challenges diminishes, leading to alterations in signal transduction and subsequent functional decline. Understanding these age-related changes is essential for developing targeted therapies aimed at enhancing skin health and resilience, but also offers a promising avenue for the treatment of skin disorders and the promotion of healthy ageing.

AI-Powered Disinfection Force: Harnessing 5G for Intelligent Distributed Object Recognition and Sanitation Fleet

With the increasing prevalence of embedded cameras in devices such as phones, robots, and vehicles, there’s a growing need to enhance their perception capabilities through advanced deep learning techniques. These systems, however, often struggle under suboptimal conditions like environmental noise. The paper addresses these challenges by proposing a 5G-enabled solution that uses a fleet of unmanned ground vehicles (UGVs) for coordinated disinfection tasks in hospital environments. Utilizing high-bandwidth, low-latency 5G networks, these UGVs can share high-quality images for distributed object recognition tasks and execute precise disinfection routines using onboard UV lamps. The proposed system includes an optimal formation algorithm for UGVs to maintain effective positioning and coordination. By leveraging 5G connectivity, the fleet can efficiently exchange sensor data and perform real-time, innovative object recognition and disinfection, presenting a significant advancement in intelligent sanitation technology.

Identification of peripheral nerve functional fascicles in Sprague-Dawley rats by the carbon quantum dot-Annexin V antibody complex

To explore a method to identify the sensory and motor fascicles of the peripheral nerve to achieve accurate peripheral nerve functional fascicle suture. The peripheral nerve Sunderland V injury model, muscle branch of the femoral nerve and saphenous nerve were established in the bilateral femoral nerves of Sprague-Dawley (SD) rats. The specific samples were grouped as follows: the main trunk of the femoral nerve was exposed bilaterally and cut with microscopic scissors in the main trunk of the femoral nerve to prepare a model of Sunderland V injury in the mixed fascicle of peripheral nerves; the muscle branch of the femoral nerve was exposed bilaterally and cut in the middle section of the muscle branch of the femoral nerve to prepare a model of Sunderland V injury in the motor fascicle of peripheral nerves; the saphenous nerve was exposed bilaterally and cut at 1 cm below the patella to prepare a model of Sunderland V injury to the sensory fascicle of the peripheral nerves. A carbon quantum dot (CD)-annexin V antibody complex was prepared and applied to the distal and proximal nerve stumps of the peripheral nerve Sunderland V injury model groups of SD rats. Under the excitation light source of a 380 nm uv lamp, fluorescence color development was observed under a fluorescence microscope after 5, 10, 15, and 20 min. At 5 min, sections of the bilateral femoral nerve trunk, muscular branches of the femoral nerve, and Sunderland V lesion of the saphenous nerve in SD rats were only dark in color under the microscope, and there was no difference in fluorescence. The intensity of the staining increased significantly for 10–20 min. The sensory fascicles and saphenous nerves of the femoral nerve trunk showed blue fluorescence under the CD-Annexin V antibody complex staining, while the motor fascicles and muscle branches of the femoral nerve trunk showed no fluorescence. Fluorescence intensity gradually decreased after 20 min of staining. There was no significant difference in the staining intensity at 5, 10, 15, and 20 min in each group. Our results suggest that the CD-Annexin antibody complex can be used to identify functional fascicles of peripheral nerves in SD rats.

Influence of Germicidal UV (222 nm) Lamps on Ozone, Ultrafine Particles, and Volatile Organic Compounds in Indoor Office Spaces.

Germicidal ultraviolet lamps with a peak emission at 222 nm (GUV222) are gaining prominence as a safe and effective solution to reduce disease transmission in occupied indoor environments. While previous studies have reported O3 production from GUV222, less is known about their impact on other indoor constituents affecting indoor air quality, especially in real occupied environments. In this study, the effects of GUV222 on the levels of ozone (O3), ultrafine particles (UFPs), and volatile organic compounds (VOCs) were investigated across multiple offices with varying occupancies. O3 from the GUV222 operation was observed to increase linearly (∼300 μg h-1 m-1) with a UV light path length from 0 to 3 m beyond which it stabilized. When applied in offices, the O3 production models based on continuous measurements revealed O3 production rates of 1040 ± 87 μg h-1. The resulting increases in steady-state concentrations of 5-21 μg m-3 were highly dependent on the number of office occupants. UFP production occurred during both unoccupied and occupied conditions but predominantly in newly renovated offices. Time-resolved measurements with a proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS) revealed clear alterations in office VOC concentrations. Unsurprisingly, O3 oxidation chemistry was observed, including monoterpene deprivation and 4-oxopentanal (4-OPA) production. But additionally, significant alterations from unidentified mechanisms occurred, causing increased levels of various PTR-TOF-MS signals including C2H5O2+ and C4H9+ hypothesized to arise from photoinduced formation or off-gassing during the GUV222 lamp operation.

A Zn‐MOF With Its Mixed‐Matrix Membranes for Convenient and Efficient Visualization Detection of 3‐Nitrotyrosine Biomarker in Aqueous Media and Practical Application in Serum

ABSTRACTInstant and accurate detection of 3‐nitrotyrosine (3‐NT) biomarker is an important but challenging task in clinical diagnosis, treatment, and monitoring of diseases. Herein, this work reported a Zn (II)–based metal–organic framework (MOF) {[Zn2(BDPT)(DIMB)]}n, denoted as Zn‐BDPT, synthesized by solvothermal method using bis(3,5‐dicarboxyphenyl)terephthalamide (H4BDPT) and 1,4‐di(1H‐imidazol‐1‐yl)butane (DIMB). Neighboring [Zn (COO)2] clusters were connected by BDPT4− units and DIMB to form a (2,4,4)‐connected three‐dimensional (3D) architecture. X‐ray powder diffraction (PXRD) and thermogravimetric (TGA) experiments indicated that Zn‐BDPT had good purity and stability. Zn‐BDPT could selectively and rapidly recognize 3‐NT in an aqueous environment. For rapid economic detection of 3‐NT in actual samples, mixed‐matrix membranes (MMMs) based on Zn‐BDPT were successfully prepared and named Zn‐BDPT@PMMA. The addition of 3‐NT under the UV lamp displayed an evident visible fluorescence quenching effect. Quantitative titration analysis of Zn‐BDPT@PMMA in real serum sample obtained the Ksv value of 1.13 × 104 M−1 and a limit of detection (LOD) of 0.17 μM. This report demonstrated that MOF‐based MMMs could be used as ideal candidate for luminescent probe in actual application.

A Novel Immunochromatographic Test Strip Using Lanthanide-Labeled Fluorescent Nanoparticles for the Serological Detection of Toxoplasma gondii in Dogs and Cats

Toxoplasma gondii (T. gondii) is an important zoonotic pathogen which induces both acute and chronic toxoplasmosis. Timely diagnosis of T. gondii is crucial for effective disease management. Here, we present a pioneering approach using europium (III)-chelated nanoparticles (EuNPs) in a rapid lateral flow immunochromatographic test strip (ICTS) for detecting T. gondii antibodies in serum samples. By conjugating EuNPs with Staphylococcus aureus protein A, we efficiently captured T. gondii-specific antibodies, which bound to T. gondii antigens on the test line (T-line), generating a distinct fluorescent signal. Employing this novel method, we conducted an extensive epidemiological investigation of T. gondii infections among dogs and cats in Shanghai, China. This innovative ICTS allows for rapid results within 25 min, which include a qualitative result through naked-eye observation under an ultraviolet lamp and a quantitative one derived using a strip reader. With a detection limit of 1:6400 for dog positive serum and no cross-reactivity with other canine and feline pathogens, the EuNPs-ICTS demonstrated excellent consistency with standard enzyme-linked immunosorbent assay results for dogs (κ = 0.91) and cats (κ = 0.92). In addition, 20.38% of 996 dog serum samples and 14.18% of 416 cat serum samples revealed T. gondii antibodies, highlighting the efficacy of this approach. Our study presents a rapid, sensitive, specific, and reproducible EuNPs-ICTS, serving as a promising tool for on-the-spot diagnosis of T. gondii infections in dogs and cats.

N-doped silicon QDs: facile synthesis and application as sensor for discrimination and selective detection of oxytetracycline, tetracycline, and chlortetracycline in foods.

Nitrogen-doped silicon quantum dots (N-SiQDs) with a quantum yield of up to 37.8% were simply synthesized using inexpensive and readily available silica as the silicon source. Based on the internal filter effect (IFE), both oxytetracycline (OTC) and tetracycline (TC) can effectively and rapidly quench the fluorescence of N-SiQDs at 380nm. However, interestingly, the accompanied formation of a new complex of OTC with N-SiQDs could emit fluorescence at 505nm, resulting in a gradualcolor change of the sensor from blue to yellow under the irradiation of 365nm UV lamp. Thus, a visual semi-quantitative detection of OTC was realized. In contrast, based on the aggregation-induced luminescence (AIE) effect, chlortetracycline (CTC) linearly enhanced the fluorescence intensity of N-SiQDs, which can effectively reduce other interfering signals, and can significantly improve the sensitivity and selectivity. Hence, a low limit of detection of 47nM for CTC was obtained. On account of the three distinctly different phenomena and mechanisms of N-SiQDs sensor exhibited towards OTC, TC, and CTC, a novel sensing method for discriminating and selectively measuring OTC, TC, and CTC in food was developed.

Mitochondria-Targeted NIR Ratiometric and Colorimetric Fluorescent Probe for Biothiols Based on a Thiol-Chromene Click Reaction.

In this work, a mitochondria-targeted NIR ratiometric and colorimetric fluorescent probe 1 was tactfully designed and synthesized by a novel design strategy of modifying chromene to pyridine for the first time. 1 exhibited a maximum absorption peak at 508 nm and a maximum fluorescence emission peak at 650 nm. Under the stimulus of biothiols (cysteine (Cys), homocysteine (Hcy), and glutathione (GSH)), the maximum absorption and fluorescence emission peaks of 1 blue-shifted to 448 and 541 nm, respectively, along with color changes from red to yellow under visible light and from red to green under a 365 nm ultraviolet (UV) lamp, which can be ascribed to the click reaction of biothiols with the α,β-unsaturated ketone of the chromene moiety with pyran ring-opening, phenol formation, and 1,6-elimination of the p-hydroxybenzyl moiety. 1 detected biothiols (Cys, GSH, and Hcy) with high sensitivity (LODs of 29, 23, and 16 nM for Cys, GSH, and Hcy, respectively), excellent selectivity, and fast response. Moreover, 1 can target mitochondria and image the fluctuation of intracellular biothiols by dual-emission channels.

UVB radiation suppresses Dicer expression through β-catenin.

Ultraviolet (UV) rays prompt a natural response in epidermal cells, particularly within melanocytes. The changes in gene expression and related signaling pathways in melanocytes following exposure to UVR are still not entirely understood. Our findings reveal that UVB irradiation suppresses the expression of Dicer. This repression is intricately linked to the activation of the PI3K, RSK, and WNT/β-catenin signaling pathways and is directly associated with transcriptional repression by β-catenin. Notably, we have identified specific binding sites for the LEF/β-catenin complex in the Dicer promoter. Collectively, these results emphasize the significance of the UV-induced pathway involving LEF/β-catenin, which impacts Dicer expression. UV radiation also reduced the levels of specific miRNAs known to be important in the biology of melanocytes. This pathway holds potential importance in governing melanocyte physiology.