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1.
Sci Total Environ ; 926: 172122, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38569973

RESUMO

Photodegradation via ultraviolet (UV) radiation is an important factor driving plant litter decomposition. Despite increasing attention to the role of UV photodegradation in litter decomposition, the specific impact of UV radiation on the plant litter decomposition stage within biogeochemical cycles remains unclear at regional and global scales. To clarify the variation rules of magnitude of UV effect on plant litter decomposition and their regulatory factors, we conducted a meta-analysis based on 54 published papers. Our results indicated that UV significantly promoted the mass loss of litter by facilitating decay of carbonaceous fractions and release of nitrogen and phosphorus. The promotion effect varied linearly or non-linearly with the time that litter exposed to UV, and with climatic factors. The UV effect on litter decomposition decreased first than increased on precipitation and temperature gradients, reaching its minimum in the area with a precipitation of 400-600 mm, and a temperature of 15-20 °C. This trend might be attributed to a potential equilibrium between the photofacilitation and photo-inhibition effects of UV under this condition. This variation in UV effect on precipitation gradient was in agreement with the fact that UV photodegradation effect was weakest in grassland ecosystems compared to that in forest and desert ecosystems. In addition, initial litter quality significantly influenced the magnitude of UV effect, but had no influence on the correlation between UV effect and climate gradient. Litter with lower initial nitrogen and lignin content shown a greater photodegradation effect, whereas those with higher hemicellulose and cellulose content had a greater photodegradation effect. Our study provides a comprehensive understanding of photodegradation effect on plant litter decomposition, indicates potentially substantial impacts of global enhancements of litter decomposition by UV, and highlights the necessity to quantify the contribution of photochemical minerallization pathway and microbial degradation pathway in litter decomposition.


Assuntos
Ecossistema , Raios Ultravioleta , Folhas de Planta/metabolismo , Plantas/metabolismo , Clima Desértico , Nitrogênio/metabolismo
2.
J Photochem Photobiol B ; 254: 112902, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569457

RESUMO

The effect of low artificial Ultraviolet (UV) on the DNA methylation remains controversial. This study addresses how differential photoperiods of UV radiation affect the biochemical and molecular behaviors of Cannabis indica cell suspension cultures. The cell suspensions were illuminated with the compact fluorescent lamps (CFL), emitting a combination of 10% UVB, 30% UVA, and the rest visible wavelengths for 0, 4, 8, and 16 h. The applied photoperiods influenced cell morphological characteristics. The 4 h photoperiod was the most effective treatment for improving biomass, growth index and cell viability percentage while these indices remained non-significant in the 16 h treatment. The methylation-sensitive amplified polymorphism (MASP) assay revealed that the UV radiation was epigenetically accompanied by DNA hypermethylation. The light-treated cells significantly displayed higher relative expression of the cannabidiolic| acid synthase (CBDAS) and delta9-tetrahydrocannabinolic acid synthase (THCAS) genes about 4-fold. The expression of the olivetolic acid cyclase (OAC) and olivetol synthase (OLS) genes exhibited an upward trend in response to the UV radiation. The light treatments also enhanced the proline content and protein concentration. The 4 h illumination was significantly capable of improving the cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) concentrations, in contrast with 16 h. By increasing the illumination exposure time, the activity of the phenylalanine ammonia-lyase (PAL) enzyme linearly upregulated. The highest amounts of the phenylpropanoid derivatives were observed in the cells cultured under the radiation for 4 h. Taken collective, artificial UV radiation can induce DNA methylation modifications and impact biochemical and molecular differentiation in the cell suspensions in a photoperiod-dependent manner.


Assuntos
Canabinoides , Cannabis , Cannabis/genética , Cannabis/química , Canabinoides/farmacologia , Dronabinol/farmacologia , Metilação de DNA , Raios Ultravioleta , Proliferação de Células
3.
Med Arch ; 78(2): 88-91, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566862

RESUMO

Background: Prolonged exposure to sunlight is known to induce photoaging of the skin, leading to various skin changes and disorders, such as dryness, wrinkles, irregular pigmentation, and even cancer. Ultraviolet A (UVA) and ultraviolet B (UVB) radiation are particularly responsible for causing photoaging. Objective: This study aims to identify and compare photoaging rat models exposed to UVA and UVB. Methods: This research method compared macroscopic (scoring degree of wrinkling) and microscopic (histology) signs and symptoms on skin samples of rat exposed to UVA and UVB for 4 weeks at a radiation dose of 840mJ/cm2. Results: The results of this study indicated that the degree of wrinkling was highest in rat skin exposed to UVB rays by 51% (p<0.05). UVB histological results showed that the epidermis layer (40 µm, p<0.05) was thickened and the dermis layer (283 µm, p<0.05) was thinned in the skin of mice exposed to UVB light. The UVB group, showed the density of collagen in the dermis with a mean value of 55% (p<0.05). Conclusion: Our results suggest that short-term exposure to UVB radiation (in the acute, subacute or subchronic phase) induces more rapid and pronounced damage to rat skin when compared to UVA radiation exposure.


Assuntos
Envelhecimento da Pele , Ratos , Camundongos , Animais , Pele/patologia , Raios Ultravioleta/efeitos adversos , Luz Solar
4.
Fungal Biol ; 128(2): 1714-1723, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38575245

RESUMO

The repair capacity of ultra-violet (UV) light DNA damage is important for adaptation of fungi to different ecological niches. We previously showed that in the soil-borne pathogen Fusarium oxysporum photo-reactivation dependent UV repair is induced at the germling stage and reduced at the filament stage. Here, we tested the developmental control of the transcription of photolyase, UV survival, UV repair capacity, and UV induced mutagenesis in the foliar pathogen Fusarium mangiferae. Unlike F. oxysporum, neither did we observe developmental control over photo-reactivation dependent repair nor the changes in gene expression of photolyase throughout the experiment. Similarly, photo-reactivation assisted reduction in UV induced mutagenesis was similar throughout the development of F. mangiferae but fluctuated during the development of F. oxysporum. To generate hypotheses regarding the recovery of F. mangiferae after UV exposure, an RNAseq analysis was performed after irradiation at different timepoints. The most striking effect of UV on F. mangiferae was developmental-dependent induction of translation related genes. We further report a complex response that changes during recovery time and involves translation, cell cycle and lipid biology related genes.


Assuntos
Desoxirribodipirimidina Fotoliase , Fusarium , Raios Ultravioleta , Dano ao DNA , Ciclo Celular
5.
Int J Mol Sci ; 25(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612578

RESUMO

Ultraviolet radiation (UVR) has various effects on human cells and tissues, which can lead to a variety of skin diseases and cause inconvenience to people's lives. Among them, solar dermatitis is one of the important risk factors for malignant melanoma, so prevention and treatment of solar dermatitis is very necessary. Additionally, liquiritin (LQ) has anti-inflammatory effects. In this study, we aimed to evaluate the anti-inflammatory and pro-wound healing effects of liquiritin carbomer gel cold paste (LQ-CG-CP) in vitro and in vivo. The results of MTT experiments showed no cytotoxicity of LQ at concentrations of 40 µg/mL and below and cell damage at UVB irradiation doses above 60 mJ/cm2. Moreover, LQ can promote cell migration. ELISA results also showed that LQ inhibited the elevation of the inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) after UVB irradiation. In the mouse model of solar dermatitis, 2% LQ-CG-CP showed the best therapeutic efficacy for wound healing and relief of itching compared to MEIBAO moist burn moisturizer (MEBO). What is more, the results of skin histopathological examination show that LQ-CG-CP promotes re-epithelialization, shrinks wounds, and promotes collagen production, thus promoting wound healing. Simultaneously, LQ-CG-CP reduced TNF-α, IL-1ß, and IL-6 expression. In addition, LQ-CG-CP was not observed to cause histopathological changes and blood biochemical abnormalities in mice. Overall, LQ-CG-CP has great potential for the treatment of solar dermatitis.


Assuntos
Resinas Acrílicas , Dermatite , Flavanonas , Glucosídeos , Queimadura Solar , Animais , Camundongos , Humanos , Raios Ultravioleta , Interleucina-6 , Fator de Necrose Tumoral alfa , Cicatrização , Interleucina-1beta , Anti-Inflamatórios
6.
Sci Rep ; 14(1): 8675, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622160

RESUMO

Mitochondria are essential organelles in cellular energy metabolism and other cellular functions. Mitochondrial dysfunction is closely linked to cellular damage and can potentially contribute to the aging process. The purpose of this study was to investigate the subcellular structure of mitochondria and their activities in various cellular environments using super-resolution stimulated emission depletion (STED) nanoscopy. We examined the morphological dispersion of mitochondria below the diffraction limit in sub-cultured human primary skin fibroblasts and mouse skin tissues. Confocal microscopy provides only the overall morphology of the mitochondrial membrane and an indiscerptible location of nucleoids within the diffraction limit. Conversely, super-resolution STED nanoscopy allowed us to resolve the nanoscale distribution of translocase clusters on the mitochondrial outer membrane and accurately quantify the number of nucleoids per cell in each sample. Comparable results were obtained by analyzing the translocase distribution in the mouse tissues. Furthermore, we precisely and quantitatively analyzed biomolecular distribution in nucleoids, such as the mitochondrial transcription factor A (TFAM), using STED nanoscopy. Our findings highlight the efficacy of super-resolution fluorescence imaging in quantifying aging-related changes on the mitochondrial sub-structure in cells and tissues.


Assuntos
Mitocôndrias , Raios Ultravioleta , Humanos , Animais , Camundongos , Microscopia de Fluorescência/métodos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Células HeLa
7.
BMC Cancer ; 24(1): 477, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622563

RESUMO

BACKGROUND: Limited evidence exists on the population attributable fraction (PAF) of cancer cases and deaths in Latin America. In Peru several studies have been published regarding the PAF of various risk factors and their associated diseases. The objective of this study was to estimate the fraction of cancer cases and deaths attributable to potentially modifiable risk factors in Peru in 2018, before the COVID-19 pandemic in the population of 15 years old and older. METHODS: An ecological study was conducted using the prevalence of exposure of the Peruvian population to modifiable risk factors for cancer, the relative risk associated with each factor, and the number of cancer cases and deaths in 2018 as inputs. We used the Parkin formula with a Montecarlo statistical simulation model to calculate the PAF and confidence intervals. The number of new cancer cases and deaths attributed to each risk factor was determined by multiplying the number of cases and deaths in each gender by the PAF of each risk factor. FINDINGS: In Peru, 38.5% of new cases (34.5% in men and 42% in women) and 43.4% of cancer-related deaths (43.4% in men and 43.4% in women) were attributable to modifiable risk factors. The number of cancers attributable was 25,308 (10,439 in men and 14,869 in women) and the number of deaths attributable to cancer was 14,839 (6,953 in men and 7,886 in women). The predominant modifiable risk factors contributing to the highest number of cases and deaths were HPV infection (4,563 cases, 2,409 deaths), current tobacco use (3,348 cases, 2,180 deaths), and helicobacter pylori infection (2,677 cases, 1,873 deaths). Among the risk factors, oncogenic infections constituted the group with the highest PAF (16.6% for cases, 19.2% for deaths) followed by other unhealthy lifestyle factors (14.2% for cases, 16.7% for deaths), tobacco (7.2% for cases, 7.2% for deaths) and ultraviolet radiation (0.5% for cases, 0.3% for deaths). CONCLUSIONS: Prior to the COVID-19 pandemic, 38.5% of cancer cases and 43.4% of cancer-related deaths in Peru were linked to modifiable risk factors in the population of 15 years old and older. Most preventable cancer cases and deaths were related to oncogenic infections, primarily caused by HPV and helicobacter pylori, followed by tobacco and obesity.


Assuntos
COVID-19 , Infecções por Helicobacter , Helicobacter pylori , Neoplasias , Infecções por Papillomavirus , Masculino , Humanos , Feminino , Adolescente , Peru/epidemiologia , Raios Ultravioleta , Infecções por Helicobacter/complicações , Pandemias , Fatores de Risco , Neoplasias/epidemiologia , Neoplasias/etiologia , COVID-19/epidemiologia , COVID-19/complicações , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia
8.
J Hazard Mater ; 470: 134209, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581880

RESUMO

Weathered microplastics (MPs) exhibit different physicochemical properties compared to pristine MPs, thus, their effects on the environment and living organisms may also differ. In the present study, we investigated the gut-toxic effects of virgin polypropylene MPs (PP) and UV-weathered PP MPs (UV-PP) on zebrafish. The zebrafish were exposed to the two types of PP MPs at a concentration of 50 mg/L each for 14 days. After exposure, MPs accumulated primarily within the gastrointestinal tract, with UV-PP exhibiting a higher accumulation than PP. The ingestion of PP and UV-PP induced gut damage in zebrafish and increased the gene expression and levels of enzymes related to oxidative stress and inflammation, with no significant differences between the two MPs. Analysis of the microbial community confirmed alterations in the abundance and diversity of zebrafish gut microorganisms in the PP and UV-PP groups, with more pronounced changes in the PP-exposed group. Moreover, the Kyoto Encyclopedia of Genes and Genomes pathway analysis confirmed the association between changes in the gut microorganisms at the phylum and genus levels with cellular responses, such as oxidative stress, inflammation, and tissue damage. This study provides valuable insights regarding the environmental impact of MPs on organisms.


Assuntos
Microbioma Gastrointestinal , Microplásticos , Polipropilenos , Raios Ultravioleta , Poluentes Químicos da Água , Peixe-Zebra , Animais , Microplásticos/toxicidade , Polipropilenos/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos da radiação , Poluentes Químicos da Água/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos da radiação
9.
Sci Total Environ ; 927: 172220, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588733

RESUMO

The microbial carbon (C) flux in the ocean is a key functional process governed by the excretion of organic carbon by phytoplankton (EOC) and heterotrophic bacterial carbon demand (BCD). Ultraviolet radiation (UVR) levels in upper mixed layers and increasing atmospheric dust deposition from arid regions may alter the degree of coupling in the phytoplankton-bacteria relationship (measured as BCD:EOC ratio) with consequences for the C-flux through these compartments in marine oligotrophic ecosystem. Firstly, we performed a field study across the south-western (SW) Mediterranean Sea to assess the degree of coupling (BCD:EOC) and how it may be related to metabolic balance (total primary production: community respiration; PPT:CR). Secondly, we conducted a microcosm experiment in two contrasting areas (heterotrophic nearshore and autotrophic open sea) to test the impact of UVR and dust interaction on microbial C flux. In the field study, we found that BCD was not satisfied by EOC (i.e., BCD:EOC >1; uncoupled phytoplankton-bacteria relationship). BCD:EOC ratio was negatively related to PPT:CR ratio across the SW Mediterranean Sea. A spatial pattern emerged, i.e. in autotrophic open sea stations uncoupling was less severe (BCD:EOC ranged 1-2), whereas heterotrophic nearshore stations uncoupling was more severe (BCD:EOC > 2). In the experimental study, in the seawater both enriched with dust and under UVR, BCD:EOC ratio decreased by stimulating autotrophic processes (particulate primary production (PPP) and EOC) in the heterotrophic nearshore area, whereas BCD:EOC increased by stimulating heterotrophic processes [heterotrophic bacterial production (HBP), bacterial growth efficiency (BGE), bacterial respiration (BR)] in the autotrophic open sea. Our results show that this spatial pattern could be reversed under future UVR × Dust scenario. Overall, the impact of greater dust deposition and higher UVR levels will alter the phytoplankton-bacteria C-flux with consequences for the productivity of both communities, their standing stocks, and ultimately, the ecosystem's metabolic balance at the sea surface.


Assuntos
Bactérias , Poeira , Fitoplâncton , Raios Ultravioleta , Fitoplâncton/efeitos da radiação , Mar Mediterrâneo , Poeira/análise , Bactérias/metabolismo , Água do Mar/microbiologia , Ciclo do Carbono , África do Norte , Ecossistema
10.
J Colloid Interface Sci ; 666: 176-188, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593652

RESUMO

AIM: Ultraviolet B (UVB) radiation can compromise the functionality of the skin barrier through various mechanisms. We hypothesize that UVB induce photochemical alterations in the components of the outermost layer of the skin, known as the stratum corneum (SC), and modulate its antioxidative defense mechanisms. Catalase is a well-known antioxidative enzyme found in the SC where it acts to scavenge reactive oxygen species. However, a detailed characterization of acute UVB exposure on the activity of native catalase in the SC is lacking. Moreover, the effects of UVB irradiation on the molecular dynamics and organization of the SC keratin and lipid components remain unclear. Thus, the aim of this work is to characterize consequences of UVB exposure on the structural and antioxidative properties of catalase, as well as on the molecular and global properties of the SC matrix surrounding the enzyme. EXPERIMENTS: The effect of UVB irradiation on the catalase function is investigated by chronoamperometry with a skin covered oxygen electrode, which probes the activity of native catalase in the SC matrix. Circular dichroism is used to explore changes of the catalase secondary structure, and gel electrophoresis is used to detect fragmentation of the enzyme following the UVB exposure. UVB induced alterations of the SC molecular dynamics and structural features of the SC barrier, as well as its water sorption behavior, are investigated by a complementary set of techniques, including natural abundance 13C polarization transfer solid-state NMR, wide-angle X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, and dynamic vapor sorption microbalance. FINDINGS: The findings show that UVB exposure impairs the antioxidative function of catalase by deactivating both native catalase in the SC matrix and lyophilized catalase. However, UVB radiation does not alter the secondary structure of the catalase nor induce any observable enzyme fragmentation, which otherwise could explain deactivation of its function. NMR measurements on SC samples show a subtle increase in the molecular mobility of the terminal segments of the SC lipids, accompanied by a decrease in the mobility of lipid chain trans-gauche conformers after high doses of UVB exposure. At the same time, the NMR data suggest increased rigidity of the polypeptide backbone of the keratin filaments, while the molecular mobility of amino acid residues in random coil domains of keratin remain unaffected by UVB irradiation. The FTIR data show a consistent decrease in absorbance associated with lipid bond vibrations, relative to the main protein bands. Collectively, the NMR and FTIR data suggest a small modification in the composition of fluid and solid phases of the SC lipid and protein components after UVB exposure, unrelated to the hydration capacity of the SC tissue. To conclude, UVB deactivation of catalase is anticipated to elevate oxidative stress of the SC, which, when coupled with subtle changes in the molecular characteristics of the SC, may compromise the overall skin health and elevate the likelihood of developing skin disorders.


Assuntos
Catalase , Raios Ultravioleta , Catalase/metabolismo , Catalase/química , Humanos , Epiderme/efeitos da radiação , Epiderme/metabolismo , Epiderme/enzimologia , Pele/efeitos da radiação , Pele/metabolismo , Pele/química , Queratinas/química , Queratinas/metabolismo
11.
Glob Chang Biol ; 30(4): e17279, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619007

RESUMO

There are close links between solar UV radiation, climate change, and plastic pollution. UV-driven weathering is a key process leading to the degradation of plastics in the environment but also the formation of potentially harmful plastic fragments such as micro- and nanoplastic particles. Estimates of the environmental persistence of plastic pollution, and the formation of fragments, will need to take in account plastic dispersal around the globe, as well as projected UV radiation levels and climate change factors.


Assuntos
Energia Solar , Raios Ultravioleta , Raios Ultravioleta/efeitos adversos , Mudança Climática , Poluição Ambiental , Tempo (Meteorologia)
12.
Eur J Dermatol ; 34(1): 26-30, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557455

RESUMO

Gel manicures have become part of a popular personal care service in the last two decades due to increased longevity of the polish and the added strength to the nail plate. Prolonged exposure to nail ultraviolet (UV) lamps is required to cure the gel polish. Despite the increased use of UV nail lamps, there is limited consensus in the literature on the risk of skin malignancy associated with UV nail lamps. The objective of this article was to provide a systematic review of the risk of skin malignancy associated with the use of UV nail lamps and to synthesize evidence-based recommendations on their safe usage. A systematic review of the literature was conducted on the databases, Medline and Embase, in accordance with PRISMA guidelines. The search yielded 2,331 non-duplicate articles. Nine were ultimately included, of which three were case reports, one was a cross-sectional study, and five were experimental studies. The risk of bias per the Joanna Briggs Institute guidelines was high or unclear, likely due to the number of case reports included. Prolonged and repeated exposure to UV nail lamps may pose a low risk of skin cancer. It is important to note that the available evidence is weak, and patients should be informed about the limited data to make their own decisions. Dermatologists and other healthcare providers should be updated with the latest evidence to address patients' concerns about gel manicures and suggest practices which can effectively reduce the risk of cutaneous malignancy associated with gel manicures, such as the use of UV-blocking gloves or properly applied sunscreens.


Assuntos
Beleza , Neoplasias Cutâneas , Humanos , Estudos Transversais , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/patologia , Unhas/patologia , Protetores Solares , Raios Ultravioleta/efeitos adversos
14.
Sci Rep ; 14(1): 9440, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658799

RESUMO

Although previous studies have examined the signaling pathway involved in melanogenesis through which ultraviolet (UV) or α-melanocyte-stimulating hormones (α-MSH) stimuli act as key inducers to produce melanin at the stratum basal layer of the epidermis, the signaling pathway regulating melanogenesis is still controversial. This study reports that α-MSH, not UVA and UVB, acted as a major stimulus of melanogenesis in B16F10 melanoma cells. Signaling pathway analysis using gene knockdown technology and chemical inhibitors, the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK)/p90 ribosomal S6 kinase 2 (RSK2) played an important role in melanogenesis. Unexpectedly, LY294002, a PI3K inhibitor, increased melanogenesis without UV or α-MSH stimulation, suggesting that the PI3K/AKT signaling pathway may not be a major signaling pathway for melanogenesis. Chemical inhibition of the MEKs/ERKs/RSK2 signaling pathway using U0126 or BI-D1870 suppressed melanogenesis by stimulation of UVA or α-MSH stimulation, or both. In particular, the genetic depletion of RSK2 or constitutive active (CA)-RSK2 overexpression showed that RSK2 plays a key role in melanogenesis. Interestingly, forkhead box protein O4 (FOXO4) was phosphorylated by RSK2, resulting in the increase of FOXO4's transactivation activity. Notably, the FOXO4 mutant harboring serine-to-alanine replacement at the phosphorylation sites totally abrogated the transactivation activity and reduced melanin production, indicating that RSK2-mediated FOXO4 activity plays a key role in melanogenesis. Furthermore, kaempferol, a flavonoid inhibiting the RSK2 activity, suppressed melanogenesis. In addition, FOXO4-wt overexpression showed that FOXO4 enhance melanin synthesis. Overall, the RSK2-FOXO4 signaling pathway plays a key role in modulating melanogenesis.


Assuntos
Melaninas , Pteridinas , Proteínas Quinases S6 Ribossômicas 90-kDa , Transdução de Sinais , alfa-MSH , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Melaninas/biossíntese , Melaninas/metabolismo , Animais , alfa-MSH/metabolismo , alfa-MSH/farmacologia , Camundongos , Linhagem Celular Tumoral , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Raios Ultravioleta , Morfolinas/farmacologia , Cromonas/farmacologia , Nitrilas/farmacologia , Butadienos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Melanoma Experimental/metabolismo , 60451
15.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 233-240, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38650128

RESUMO

Skin photoaging affects appearance and is associated with a variety of skin diseases, even skin cancer. Therefore, the prevention and treatment of skin photoaging is very important. However, there is a lack of effective evaluation methods, so it is an urgent problem to explore a comprehensive, non-invasive and in vivo evaluation method. Adipose-derived mesenchymal stem cells (ADSCs) are widely used to improve skin conditions as easier to obtain and positive effects. Recently, as the development of ultrasound technology, skin ultrasound has been widely used. Changes in skin layer and structure can be observed by high-frequency ultrasound (HFUS). In addition, Shear wave elastography (SWE) technology can be used to monitor the change of skin hardness. However, it is necessary to further explore the ultrasound parameters in interpreting histological changes. We simulate the progression and treatment process of human skin photoaging by using UVB-induced nude mice skin photoaging model and ADSCs injection. The analysis of the degree and therapeutic effect of skin photoaging was conducted by HFUS, SWE and to verify with histopathology. Our study aims to clarify the value of HFUS combined SWE techniques in evaluating the degree and therapeutic efficacy of skin photoaging, which provides theoretical basis for diagnosis and treatment evaluation systems.


Assuntos
Células-Tronco Mesenquimais , Camundongos Nus , Envelhecimento da Pele , Pele , Raios Ultravioleta , Animais , Envelhecimento da Pele/efeitos da radiação , Células-Tronco Mesenquimais/citologia , Humanos , Pele/efeitos da radiação , Pele/patologia , Tecido Adiposo/citologia , Técnicas de Imagem por Elasticidade , Transplante de Células-Tronco Mesenquimais/métodos , Camundongos , Feminino
16.
Luminescence ; 39(4): e4746, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38644460

RESUMO

The use of photochromism to increase the credibility of consumer goods has shown great promise. To provide mechanically dependable anticounterfeiting nanofibres, it has also been critical to improve the engineering processes of authentication patterns. Mechanically robust and photoluminescent electrospun poly(ethylene oxide)/glass (PGLS) nanofibres (150-350 nm) immobilized with nanoparticles of lanthanide-doped aluminate (NLA; 8-15 nm) were developed using electrospinning technology for anticounterfeiting purposes. The provided nanofibrous membranes changed colour from transparent to green when irradiated with ultraviolet light. By delivering NLA with homogeneous distribution without aggregations, we were able to keep the nanofibrous membrane transparent. When excited at 365 nm, NLA@PGLS nanofibres showed an emission intensity at 517 nm. The hydrophobicity of NLA@PGLS nanofibres improved by raising the pigment concentration as the contact angle was increased from 146.4° to 160.3°. After being triggered by ultraviolet light, NLA@PGLS showed quick and reversible photochromism without fatigue. It was shown that the suggested method can be applied to reliably produce various anticounterfeiting materials.


Assuntos
Vidro , Nanofibras , Polietilenoglicóis , Raios Ultravioleta , Nanofibras/química , Polietilenoglicóis/química , Vidro/química , Tamanho da Partícula , Propriedades de Superfície
17.
Food Microbiol ; 121: 104518, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637080

RESUMO

Pulsed light (PL) inactivates microorganisms by UV-rich, high-irradiance and short time pulses (250 µs) of white light with wavelengths from 200 nm to 1100 nm. PL is applied for disinfection of food packaging material and food-contact equipment. Spores of seven Bacillus ssp. strains and one Geobacillus stearothermophilus strain and conidia of filamentous fungi (One strain of Aspergillus brasiliensis, A. carbonarius and Penicillium rubens) were submitted to PL (fluence from 0.23 J/cm2 to 4.0 J/cm2) and UVC (at λ = 254 nm; fluence from 0.01 J/cm2 to 3.0 J/cm2). One PL flash at 3 J/cm2 allowed at least 3 log-reduction of all tested microorganisms. The emetic B. cereus strain F4810/72 was the most resistant of the tested spore-forming bacteria. The PL fluence to 3 log-reduction (F3 PL) of its spores suspended in water was 2.9 J/cm2 and F3 UVC was 0.21 J/cm2, higher than F3 PL and F3 UVC of spores of B. pumilus SAFR-032 2.0 J/cm2 and 0.15 J/cm2, respectively), yet reported as a highly UV-resistant spore-forming bacterium. PL and UVC sensitivity of bacterial spores was correlated. Aspergillus spp. conidia suspended in water were poorly sensitive to PL. In contrast, PL inactivated Aspergillus spp. conidia spread on a dry surface more efficiently than UVC. The F2 PL of A. brasiliensis DSM1988 was 0.39 J/cm2 and F2 UVC was 0.83 J/cm2. The resistance of spore-forming bacteria to PL could be reasonably predicted from the knowledge of their UVC resistance. In contrast, the sensitivity of fungal conidia to PL must be specifically explored.


Assuntos
Esporos Bacterianos , Raios Ultravioleta , Esporos Bacterianos/fisiologia , Esporos Fúngicos , Luz , Bactérias , Água
18.
Invest Ophthalmol Vis Sci ; 65(4): 24, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38597722

RESUMO

Purpose: Conjunctival squamous cell carcinoma (conjSCC) is more prevalent and aggressive in sub-Saharan African countries compared with the rest of the world. This study aims to compare the genomic, immunophenotypic, and histologic features between patients from the United States and Ethiopia, to identify etiopathogenic mechanisms and unveil potential treatment strategies. Methods: We compared histologic features and mutational profiles using whole exome sequencing, high-risk human papillomavirus (HPV) status, PD-L1 expression, and tumor-infiltrating lymphocytes in conjSCC tumors of patients from Ethiopia (ETH; n = 25) and the United States (from MD Anderson [the MDA cohort]; n = 29). Genomic alterations were compared with SCCs from other anatomic sites using data from The Cancer Genome Atlas. Results: Solar elastosis was seen in 78% of ETH and 10% of MDA samples. Thicker tumors had higher density of CD8+ and CD3+ cells. HPV status was similar between the cohorts (ETH = 21% and MDA = 28%). The mean tumor mutation burden (TMB) was significantly higher in conjSCC (3.01/Mb, log10) and cutaneous SCC compared other SCC subtypes. ETH samples had higher TMB compared to the MDA cohort (3.34 vs. 2.73). Mutations in genes associated with ultraviolet light (UV) signature were most frequently encountered (SBS7b = 74% and SBS7a = 72%), with higher prevalence in the ETH cohort, whereas SBS2 and SBS13 signatures were more common among MDA HPV+ conjSCCs. Conclusions: Our findings suggest that UV exposure may play a major role in conjSCC, with a higher prevalence in the ETH cohort compared with the MDA cohort, where HPV also contributes.


Assuntos
Infecções por Papillomavirus , Raios Ultravioleta , Humanos , Infecções por Papillomavirus/genética , Genômica , Túnica Conjuntiva , População Negra
19.
J Nanobiotechnology ; 22(1): 199, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654266

RESUMO

Considering the high recrudescence and the long-lasting unhealed large-sized wound that affect the aesthetics and cause dysfunction after resection of maxillofacial malignant skin tumors, a groundbreaking strategy is urgently needed. Photothermal therapy (PTT), which has become a complementary treatment of tumors, however, is powerless in tissue defect regeneration. Therefore, a novel multifunctional sodium nitroprusside and Fe2+ ions loaded microneedles (SNP-Fe@MNs) platform was fabricated by accomplishing desirable NIR-responsive photothermal effect while burst releasing nitric oxide (NO) after the ultraviolet radiation for the ablation of melanoma. Moreover, the steady releasing of NO in the long term by the platform can exert its angiogenic effects via upregulating multiple related pathways to promote tissue regeneration. Thus, the therapeutic dilemma caused by postoperative maxillofacial skin malignancies could be conquered through promoting tumor cell apoptosis via synergistic PTT-gas therapy and subsequent regeneration process in one step. The bio-application of SNP-Fe@MNs could be further popularized based on its ideal bioactivity and appealing features as a strategy for synergistic therapy of other tumors occurred in skin.


Assuntos
Melanoma , Óxido Nítrico , Terapia Fototérmica , Neoplasias Cutâneas , Animais , Terapia Fototérmica/métodos , Camundongos , Neoplasias Cutâneas/terapia , Melanoma/terapia , Óxido Nítrico/metabolismo , Óxido Nítrico/farmacologia , Linhagem Celular Tumoral , Agulhas , Humanos , Nitroprussiato/farmacologia , Apoptose/efeitos dos fármacos , Pele , Ferro/química , Raios Ultravioleta
20.
Int Ophthalmol ; 44(1): 145, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498219

RESUMO

PURPOSE: To compare the visual, refractive, and topographic outcomes of a high irradiance accelerated corneal crosslinking (ACXL) protocol after a 12-month follow-up between pediatric and adult patients with progressive keratoconus (KC). METHODS: Retrospective, comparative, cohort study. Patients with KC were divided into two groups: pediatric (≤ 18 years) and adult (> 18 years). All of them were managed with epi-OFF ACXL (30 mW/cm2, 8 min, pulsed 1:1 on and off = 7.2 J/cm2). Visual, refractive, and topographic values were measured preoperatively and at 1, 3, 6, and 12 months postoperative. KC progression, defined as a Kmax increase of ≥ 1D during follow-up, was recorded. RESULTS: Eighty-nine eyes (53 patients) were included for analysis; 45 (50.6%) eyes were from pediatric patients and 44 (49.4%) from adults. At one-year follow-up, pediatric patients experienced significantly higher rates of progression (22.2% vs. 4.5%, p = .014). Contrariwise, female gender (Beta = - 3.62, p = .018), a baseline uncorrected visual acuity of Snellen ≥ 20/60 (Beta = - 5.96, p = .007), and being ≥ 15 years at ACXL treatment (Beta = - 0.31, p = .021) were associated with non-progressive disease. A significant improvement in best-corrected visual acuity, Kmin, Km, and Kmax was recorded in both groups. Overall, 86.5% of eyes from both groups showed Kmax stabilization or improvement. CONCLUSIONS: Despite the similarity in visual, refractive, and topographic outcomes in both groups, younger age was associated with KC progression after ACXL at one year of follow-up.


Assuntos
Ceratocone , Fotoquimioterapia , Adulto , Humanos , Feminino , Criança , Ceratocone/diagnóstico , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Crosslinking Corneano , Estudos Retrospectivos , Estudos de Coortes , Riboflavina/uso terapêutico , Raios Ultravioleta , Topografia da Córnea/métodos , Seguimentos , Reagentes de Ligações Cruzadas/uso terapêutico , Colágeno/uso terapêutico
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