Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 105.759
Filtrar
1.
Sci Rep ; 14(1): 11642, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773346

RESUMO

Vision restoration is one of the most promising applications of optogenetics. However, it is limited due to the poor-sensitivity, slow-kinetics and narrow band absorption spectra of opsins. Here, a detailed theoretical study of retinal ganglion neurons (RGNs) expressed with ChRmine, ReaChR, CoChR, CatCh and their mutants, with near monochromatic LEDs, and broadband sunlight, halogen lamp, RGB LED light, and pure white light sources has been presented. All the opsins exhibit improved light sensitivity and larger photocurrent on illuminating with broadband light sources compared to narrow band LEDs. ChRmine allows firing at ambient sunlight (1.5 nW/mm2) and pure white light (1.2 nW/mm2), which is lowest among the opsins considered. The broadband activation spectrum of ChRmine and its mutants is also useful to restore color sensitivity. Although ChRmine exhibits slower turn-off kinetics with broadband light, high-fidelity spikes can be evoked upto 50 Hz. This limit extends upto 80 Hz with the improved hsChRmine mutant although it requires double the irradiance compared to ChRmine. The present study shows that ChRmine and its mutants allow activation of RGNs with ambient light which is useful for goggle-free white light optogenetic retinal prostheses with improved quality of restored vision.


Assuntos
Luz , Optogenética , Células Ganglionares da Retina , Optogenética/métodos , Células Ganglionares da Retina/fisiologia , Células Ganglionares da Retina/efeitos da radiação , Humanos , Mutação , Animais , Opsinas/genética , Opsinas/metabolismo , Visão Ocular/fisiologia
2.
Bioprocess Biosyst Eng ; 47(6): 943-955, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703203

RESUMO

At present, the application of sewage treatment technologies is restricted by high sulfate concentrations. In the present work, the sulfate removal was biologically treated using an upflow anaerobic sludge blanket (UASB) in the absence/presence of light. First, the start-up of UASB for the sulfate removal was studied in terms of COD degradation, sulfate removal, and effluent pH. Second, the impacts of different operation parameters (i.e., COD/SO42- ratio, temperature and illumination time) on the UASB performance were explored. Third, the properties of sludge derived from the UASB at different time were analyzed. Results show that after 28 days of start-up, the COD removal efficiencies in both the photoreactor and non-photoreactor could reach a range of 85-90% while such reactors could achieve > 90% of sulfate being removed. Besides, higher illumination time could facilitate the removal of pollutants in the photoreactor. To sum up, the present study can provide technical support for the clean removal of sulfate from wastewater using photoreactors.


Assuntos
Luz , Esgotos , Sulfatos , Sulfatos/química , Esgotos/microbiologia , Reatores Biológicos , Anaerobiose , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/química , Purificação da Água/métodos
3.
Trop Anim Health Prod ; 56(4): 146, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722408

RESUMO

This study was planned to evaluate the impact of dichromatic lights during incubation on the hatching and post-hatch performance of broiler chickens. A total of 500 eggs of broiler breeder (Ross 308; Age 44 weeks) were evenly divided according to a completely randomized design into 4 treatments having 5 replicates and 25 eggs each. Treatments consisted of dichromatic lights Blue + Red (BR), Green + Red (GR) and Green + Blue (GB) provided at an intensity of 250 lx for 12 h a day along with a Dark (D) environment. After hatching 200 chicks (50 from each respective light group) were divided into 4 treatments with 5 replicates each having 10 chicks. Results indicated a higher embryo index (13.12%) in the GR group on the 12th day of incubation; while an ideal hatch window was observed in GR and GB (98.18% and 96.00% hatched chicks) lighting groups. In hatching traits, higher hatchability (86.15) and hatch of fertile (93.85) percentages were observed in GR lighting followed by GB, BR and Dark treatment groups; while dead-in shell embryos were lowest in the GR group. In growth performance, higher feed intake (513.20 g) and body weight (479.20 g) were observed in the GB group followed by GR, BR and dark group; and feed conversion ratio (FCR) was better in the GR group (1.06). In welfare parameters, improved physical asymmetry (0.90 mm) and tonic immobility (54.40 s) were measured in the GR group followed by GB, BR and the dark group. It was concluded that under experimental conditions when broiler breeder eggs are provided with GR lighting during incubation, it can help to improve hatchability, growth performance and welfare traits in chicks.


Assuntos
Criação de Animais Domésticos , Galinhas , Iluminação , Animais , Galinhas/crescimento & desenvolvimento , Galinhas/fisiologia , Embrião de Galinha/crescimento & desenvolvimento , Criação de Animais Domésticos/métodos , Distribuição Aleatória , Feminino , Luz
4.
Molecules ; 29(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731451

RESUMO

A novel second-generation blue fluorescent polyamidoamine dendrimer peripherally modified with sixteen 4-N,N-dimethylaninoethyloxy-1,8-naphthalimide units was synthesized. Its basic photophysical characteristics were investigated in organic solvents of different polarity. It was found that in these solvents, the dendrimer is colorless and emitted blue fluorescence with different intensities depending on their polarity. The effect of the pH of the medium on the fluorescence intensity was investigated and it was found that in the acidic medium, the fluorescence is intense and is quenched in the alkaline medium. The ability of the dendrimer to detect metal ions (Pb2+, Zn2+, Mg2+, Sn2+, Ba2+, Ni2+, Sn2+, Mn2+, Co2+, Fe3+, and Al3+) was also investigated, and it was found that in the presence of Fe3+, the fluorescent intensity was amplified more than 66 times. The antimicrobial activity of the new compound has been tested in vitro against Gram-positive B. cereus and Gram-negative P. aeruginosa. The tests were performed in the dark and after irradiation with visible light. The antimicrobial activity of the compound enhanced after light irradiation and B. cereus was found slightly more sensitive than P. aeruginosa. The increase in antimicrobial activity after light irradiation is due to the generation of singlet oxygen particles, which attack bacterial cell membranes.


Assuntos
Dendrímeros , Testes de Sensibilidade Microbiana , Naftalimidas , Poliaminas , Naftalimidas/química , Naftalimidas/farmacologia , Dendrímeros/química , Dendrímeros/farmacologia , Poliaminas/química , Poliaminas/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Fluorescência , Pseudomonas aeruginosa/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Bacillus cereus/efeitos dos fármacos , Luz , Corantes Fluorescentes/química , Espectrometria de Fluorescência
5.
Molecules ; 29(9)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38731636

RESUMO

Plant in vitro cultures can be an effective tool in obtaining desired specialized metabolites. The purpose of this study was to evaluate the effect of light-emitting diodes (LEDs) on phenolic compounds in Rhaponticum carthamoides shoots cultured in vitro. R. carthamoides is an endemic and medicinal plant at risk of extinction due to the massive harvesting of its roots and rhizomes from the natural environment. The shoots were cultured on an agar-solidified and liquid-agitated Murashige and Skoog's medium supplemented with 0.1 mg/L of indole-3-acetic acid (IAA) and 0.5 mg/L of 6-benzyladenine (BA). The effect of the medium and different treatments of LED lights (blue (BL), red (RL), white (WL), and a combination of red and blue (R:BL; 7:3)) on R. carthamoides shoot growth and its biosynthetic potential was observed. Medium type and the duration of LED light exposure did not affect the proliferation rate of shoots, but they altered the shoot morphology and specialized metabolite accumulation. The liquid medium and BL light were the most beneficial for the caffeoylquinic acid derivatives (CQAs) production, shoot growth, and biomass increment. The liquid medium and BL light enhanced the content of the sum of all identified CQAs (6 mg/g DW) about three-fold compared to WL light and control, fluorescent lamps. HPLC-UV analysis confirmed that chlorogenic acid (5-CQA) was the primary compound in shoot extracts regardless of the type of culture and the light conditions (1.19-3.25 mg/g DW), with the highest level under R:BL light. BL and RL lights were equally effective. The abundant component was also 3,5-di-O-caffeoylquinic acid, accompanied by 4,5-di-O-caffeoylquinic acid, a tentatively identified dicaffeoylquinic acid derivative, and a tricaffeoylquinic acid derivative 2, the contents of which depended on the LED light conditions.


Assuntos
Flavonoides , Luz , Brotos de Planta , Ácido Quínico , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Brotos de Planta/química , Ácido Quínico/análogos & derivados , Ácido Quínico/metabolismo , Ácido Quínico/química , Flavonoides/metabolismo , Flavonoides/química , Ácidos Indolacéticos/metabolismo
6.
Sci Rep ; 14(1): 10566, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719873

RESUMO

Conventional wastewater treatment processes are often unable to remove antibiotics with resistant compounds and low biological degradation. The need for advanced and sustainable technologies to remove antibiotics from water sources seems essential. In this regard, the effectiveness of a spinning disc photocatalytic reactor (SDPR) equipped with a visible light-activated Fe3O4@SiO2-NH2@CuO/ZnO core-shell (FSNCZ CS) thin film photocatalyst was investigated for the decomposition of amoxicillin (AMX), a representative antibiotic. Various characterization techniques, such as TEM, FESEM, EDX, AFM, XRD, and UV-Vis-DRS, were employed to study the surface morphology, optoelectronic properties, and nanostructure of the FSNCZ CS. Key operating parameters such as irradiation time, pH, initial AMX concentration, rotational speed, and solution flow rate were fine-tuned for optimization. The results indicated that the highest AMX decomposition (98.7%) was attained under optimal conditions of 60 min of irradiation time, a rotational speed of 350 rpm, a solution flow rate of 0.9 L/min, pH of 5, and an initial AMX concentration of 20 mg/L. Moreover, during the 60 min irradiation time, more than 69.95% of chemical oxygen demand and 61.2% of total organic carbon were removed. After the photocatalytic decomposition of AMX, there is a substantial increase in the average oxidation state and carbon oxidation state in SDPR from 1.33 to 1.94 and 3.2, respectively. Active species tests confirmed that ·OH and ·O2- played a dominant role in AMX decomposition. The developed SDPR, which incorporates a reusable and robust FSNCZ CS photocatalyst, demonstrates promising potential for the decomposition of organic compounds.


Assuntos
Amoxicilina , Antibacterianos , Luz , Nanoestruturas , Catálise , Antibacterianos/química , Nanoestruturas/química , Amoxicilina/química , Poluentes Químicos da Água/química , Cobre/química , Óxido de Zinco/química , Dióxido de Silício/química , Purificação da Água/métodos
7.
Food Res Int ; 186: 114382, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729736

RESUMO

Black carrot anthocyanins have gained increasing attention as natural coloring agent, owing to their higher stability than anthocyanins from berries. The stability has been attributed to their higher degree of acylation. This study investigated the impact of acylation on the stability of individual anthocyanins during storage in light and darkness. We hypothesized that the acylated anthocyanins would be more stable than the non-acylated ones. The major five anthocyanins were fractioned by semi-preparative HPLC and stored at pH 4.5 in light and darkness to investigate how acylation affected the stability. The stability was evaluated by absorption spectroscopy and mass spectrometry (MS). Two of the anthocyanins were non-acylated; 3-xylosyl(glucosyl)galactoside and cyanidin 3-xylosylgalactoside, and three were acylated; cyanidin 3-xylosyl(sinapolyglucosyl)galacto-side, cyanidin 3-xylosyl(feruloylglu-cosyl)galactoside, and cyanidin 3-xylosyl(coumaroyl-glucosyl)galactoside. Both methods (spectroscopy and MS) showed a clear effect of acylation when stored in light, but surprisingly the two non-acylated anthocyanins, showed higher stability than the three acylated ones.


Assuntos
Antocianinas , Daucus carota , Luz , Antocianinas/química , Antocianinas/análise , Acilação , Daucus carota/química , Daucus carota/efeitos da radiação , Cromatografia Líquida de Alta Pressão , Escuridão , Armazenamento de Alimentos/métodos , Espectrometria de Massas , Concentração de Íons de Hidrogênio
8.
Biotechnol J ; 19(5): e2400023, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38719589

RESUMO

The discovery of antibiotics has noticeably promoted the development of human civilization; however, antibiotic resistance in bacteria caused by abusing and overusing greatly challenges human health and food safety. Considering the worsening situation, it is an urgent demand to develop emerging nontraditional technologies or methods to address this issue. With the expanding of synthetic biology, optogenetics exhibits a tempting prospect for precisely regulating gene expression in many fields. Consequently, it is attractive to employ optogenetics to reduce the risk of antibiotic resistance. Here, a blue light-controllable gene expression system was established in Escherichia coli based on a photosensitive DNA-binding protein (EL222). Further, this strategy was successfully applied to repress the expression of ß-lactamase gene (bla) using blue light illumination, resulting a dramatic reduction of ampicillin resistance in engineered E. coli. Moreover, blue light was utilized to induce the expression of the mechanosensitive channel of large conductance (MscL), triumphantly leading to the increase of streptomycin susceptibility in engineered E. coli. Finally, the increased susceptibility of ampicillin and streptomycin was simultaneously induced by blue light in the same E. coli cell, revealing the excellent potential of this strategy in controlling multidrug-resistant (MDR) bacteria. As a proof of concept, our work demonstrates that light can be used as an alternative tool to prolong the use period of common antibiotics without developing new antibiotics. And this novel strategy based on optogenetics shows a promising foreground to combat antibiotic resistance in the future.


Assuntos
Antibacterianos , Escherichia coli , Luz , Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Antibacterianos/farmacologia , Optogenética/métodos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Ampicilina/farmacologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Farmacorresistência Bacteriana/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Estreptomicina/farmacologia , Luz Azul
9.
Int J Mol Sci ; 25(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38732166

RESUMO

This current study assessed the impacts of morphology adjustment of perovskite BiFeO3 (BFO) on the construction and photocatalytic activity of P-infused g-C3N4/U-BiFeO3 (U-BFO/PCN) heterostructured composite photocatalysts. Favorable formation of U-BFO/PCN composites was attained via urea-aided morphology-controlled hydrothermal synthesis of BFO followed by solvosonication-mediated fusion with already synthesized P-g-C3N4 to form U-BFO/PCN composites. The prepared bare and composite photocatalysts' morphological, textural, structural, optical, and photocatalytic performance were meticulously examined through various analytical characterization techniques and photodegradation of aqueous rhodamine B (RhB). Ellipsoids and flakes morphological structures were obtained for U-BFO and BFO, and their effects on the successful fabrication of the heterojunctions were also established. The U-BFO/PCN composite exhibits 99.2% efficiency within 20 min of visible-light irradiation, surpassing BFO/PCN (88.5%), PCN (66.8%), and U-BFO (26.1%). The pseudo-first-order kinetics of U-BFO/PCN composites is 2.41 × 10-1 min-1, equivalent to 2.2 times, 57 times, and 4.3 times of BFO/PCN (1.08 × 10-1 min-1), U-BFO, (4.20 × 10-3 min-1), and PCN, (5.60 × 10-2 min-1), respectively. The recyclability test demonstrates an outstanding photostability for U-BFO/PCN after four cyclic runs. This improved photocatalytic activity exhibited by the composites can be attributed to enhanced visible-light utilization and additional accessible active sites due to surface and electronic band modification of CN via P-doping and effective charge separation achieved via successful composites formation.


Assuntos
Bismuto , Fotólise , Rodaminas , Catálise , Bismuto/química , Rodaminas/química , Luz , Compostos Férricos/química , Compostos de Nitrogênio/química , Titânio/química , Processos Fotoquímicos , Nitrilas/química , Cinética , Grafite , Óxidos , Compostos de Cálcio
10.
Int J Mol Sci ; 25(9)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38732247

RESUMO

To explore the impact of shade treatment on grape berries, 'Marselan' grape berries were bagged under different light transmission rates (100% (CK), 75% (A), 50% (B), 25% (C), 0% (D)). It was observed that this treatment delayed the ripening of the grape berries. The individual weight of the grape berries, as well as the content of fructose, glucose, soluble sugars, and organic acids in the berries, was measured at 90, 100, and 125 days after flowering (DAF90, DAF100, DAF125). The results revealed that shading treatment reduced the sugar content in grape berries; the levels of fructose and glucose were higher in the CK treatment compared to the other treatments, and they increased with the duration of the shading treatment. Conversely, the sucrose content exhibited the opposite trend. Additionally, as the weight of the grape berries increased, the content of soluble solids and soluble sugars in the berries also increased, while the titratable acidity decreased. Furthermore, 16 differentially expressed genes (DEGs) were identified in the photosynthesis-antenna protein pathway from the transcriptome sequencing data. Correlation analysis revealed that the expression levels of genes VIT_08s0007g02190 (Lhcb4) and VIT_15s0024g00040 (Lhca3) were positively correlated with sugar content in the berries at DAF100, but negatively correlated at DAF125. qRT-PCR results confirmed the correlation analysis. This indicates that shading grape clusters inhibits the expression of genes in the photosynthesis-antenna protein pathway in the grape berries, leading to a decrease in sugar content. This finding contributes to a deeper understanding of the impact mechanisms of grape cluster shading on berry quality, providing important scientific grounds for improving grape berry quality.


Assuntos
Frutas , Regulação da Expressão Gênica de Plantas , Fotossíntese , Proteínas de Plantas , Açúcares , Vitis , Vitis/genética , Vitis/metabolismo , Vitis/efeitos da radiação , Frutas/genética , Frutas/metabolismo , Frutas/efeitos da radiação , Fotossíntese/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Açúcares/metabolismo , Luz
11.
Physiol Plant ; 176(3): e14339, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736185

RESUMO

Caulerpa is a marine green macroalga distinguished by a large single cell with multiple nuclei. It also exhibits remarkable morphological intraspecies variations, in response to diverse environmental types. However, the molecular mechanisms underlying this phenotypic plasticity remain poorly understood. In this work, we compare the transcriptomes of Caulerpa okamurae Weber Bosse, 1897 displaying altered phenotypes of cultivation and natural phenotypes and investigate significantly regulated genes and their biological functions using differential expression analyses. We observe light-harvesting complex upregulation and cellular framework stability downregulation in altered phenotypes compared to the natural phenotypes. Intertidal macrophytes reduce light capture to avoid photodamage and regulate their morphology to protect against wave damage. In contrast, the lower light conditions and the cultivation environment augment light capture and increase a morphology prioritizing light trapping. Moreover, the addition of simulated wave-sweeping stimuli induces a return to the natural morphology under high-light conditions, showing how mechanical stress affects morphological organization in C. okamurae. We provide detailed gene expression patterns in C. okamurae under varying light intensities and water conditions, suggesting a distinct influence on its morphological traits.


Assuntos
Caulerpa , Fenótipo , Transcriptoma , Transcriptoma/genética , Caulerpa/genética , Caulerpa/fisiologia , Luz , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica
12.
Vestn Oftalmol ; 140(2. Vyp. 2): 34-42, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38739129

RESUMO

PURPOSE: This study analyzes changes in light sensitivity in each test point of the visual field in patients with different stages of glaucoma. MATERIAL AND METHODS: The data of a prospective analytical case-control study were analyzed. All patients underwent assessment of retinal light sensitivity and its variability in 54 points corresponding to the 24-2 program. Mean light sensitivity values were calculated in each point. Intergroup analysis was performed to evaluate changes in light sensitivity in each point. RESULTS: The range of light sensitivity decrease in the early glaucoma group compared to the control group was from 1.5 to 3.6 dB. The range of light sensitivity decrease in the moderate glaucoma group compared to the control group was from 2.1 to 11.5 dB, and compared to the early glaucoma group - from -0.9 to 7.9 dB. The most frequent decrease in light sensitivity was detected in the nasal sector and along the horizontal line in the upper half of the visual field. This trend persisted within the central 10 degrees of the visual field. The range of light sensitivity decrease in the advanced glaucoma group compared to the control group was from 14.1 to 28.0 dB, and compared to the early glaucoma group - from 11.35 to 26.08 dB, compared to the moderate glaucoma group - from 9.1 to 23.5 dB. The most frequent and severe decrease in light sensitivity was detected in the paracentral zone in the lower half of the visual field. CONCLUSION: The study analyzed the trends in the development of glaucoma from the early to the advanced stage. The most frequent and severe defect in light sensitivity in cases of verified advanced glaucoma was found in the lower half of the visual field. Points No. 32, 33 and 40 can be indicated as the area of interest in assessing the progression of glaucoma, as they were found to have the most profound changes in light sensitivity as glaucoma progressed.


Assuntos
Progressão da Doença , Glaucoma , Testes de Campo Visual , Campos Visuais , Humanos , Campos Visuais/fisiologia , Glaucoma/fisiopatologia , Glaucoma/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Testes de Campo Visual/métodos , Estudos Prospectivos , Idoso , Estudos de Casos e Controles , Luz
13.
Vestn Oftalmol ; 140(2. Vyp. 2): 116-122, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38739140

RESUMO

PURPOSE: This study assesses the light sensitivity and its variability in each point of the visual field in patients without glaucoma and with different stages of glaucoma. MATERIAL AND METHODS: The data of a prospective analytical case-control study involving 500 patients were analyzed. The initial examination of all patients was performed using basic ophthalmological methods, including static perimetry. Retinal light sensitivity and its variability were assessed in 54 points corresponding to the Humphrey 24-2 program. Mean deviation and pattern standard deviation of light sensitivity were calculated for each point. RESULTS: The lowest light sensitivity values in patients with moderate glaucoma were found in the periphery of the nasal sector, at point No. 27 - 14.4 dB, and at points No. 24-26 along the horizontal axis from the nasal side - from 17.7 to 22.7 dB. The maximum variability of light sensitivity was found in the nasal sector on both sides of the horizontal line - from 10.7 to 11.5 dB. The average light sensitivity above the horizontal axis in patients with advanced glaucoma was 10.8 dB, which is 2 dB higher than in the lower half of the visual field - 8.8 dB. The highest light sensitivity values were found at points No. 24 - 17.7 dB and No. 31 - 16.78 dB, the lowest - at point No. 32 - 4.5 dB. The average variability values of light sensitivity in the upper half of the visual field were 9.6 dB, which is 1 dB less than in the lower half of the visual field - 10.6 dB. CONCLUSION: According to our data, points No. 32 and No. 40 are of particular interest in the diagnostic plan. In these loci, the highest light sensitivity values were determined in early and moderate glaucoma. However, the values in these points decrease significantly in advanced glaucoma. It can be assumed that changes in light sensitivity in these loci at the early stages of glaucoma may be a predictor of glaucoma progression.


Assuntos
Glaucoma , Retina , Testes de Campo Visual , Campos Visuais , Humanos , Campos Visuais/fisiologia , Testes de Campo Visual/métodos , Glaucoma/fisiopatologia , Glaucoma/diagnóstico , Pessoa de Meia-Idade , Masculino , Feminino , Retina/fisiopatologia , Estudos Prospectivos , Adulto , Luz , Idoso , Limiar Sensorial/fisiologia , Estudos de Casos e Controles , Reprodutibilidade dos Testes
14.
Int J Mol Sci ; 25(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38732009

RESUMO

The interaction between light and phytohormones is crucial for plant growth and development. The practice of supplementing light at night during winter to promote pitaya flowering and thereby enhance yield has been shown to be crucial and widely used. However, it remains unclear how supplemental winter light regulates phytohormone levels to promote flowering in pitaya. In this study, through analyzing the transcriptome data of pitaya at four different stages (NL, L0, L1, L2), we observed that differentially expressed genes (DEGs) were mainly enriched in the phytohormone biosynthesis pathway. We further analyzed the data and found that cytokinin (CK) content first increased at the L0 stage and then decreased at the L1 and L2 stages after supplemental light treatment compared to the control (NL). Gibberellin (GA), auxin (IAA), salicylic acid (SA), and jasmonic acid (JA) content increased during the formation of flower buds (L1, L2 stages). In addition, the levels of GA, ethylene (ETH), IAA, and abscisic acid (ABA) increased in flower buds after one week of development (L2f). Our results suggest that winter nighttime supplemental light can interact with endogenous hormone signaling in pitaya, particularly CK, to regulate flower bud formation. These results contribute to a better understanding of the mechanism of phytohormone interactions during the induction of flowering in pitaya under supplemental light in winter.


Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Luz , Reguladores de Crescimento de Plantas , Estações do Ano , Reguladores de Crescimento de Plantas/metabolismo , Flores/metabolismo , Flores/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Citocininas/metabolismo , Giberelinas/metabolismo , Ipomoea nil/metabolismo , Ipomoea nil/genética , Transcriptoma , Perfilação da Expressão Gênica , Ciclopentanos , Oxilipinas
15.
Carbohydr Polym ; 337: 122160, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710575

RESUMO

Sterilisation technologies are essential to eliminate foodborne pathogens from food contact surfaces. However, most of the current sterilisation methods involve high energy and chemical consumption. In this study, a photodynamic inactivation coating featuring excellent antibacterial activity was prepared by dispersing curcumin as a plant-based photosensitiser in a chitosan solution. The coating generated abundant reactive oxygen species (ROS) after light irradiation at 420 nm, which eradicated ≥99.999 % of Escherichia coli O157:H7. It was also found that ROS damaged the cell membrane, leading to the leakage of cell contents and cell shrinkage on the basis of chitosan. In addition, the production of ROS first excited the bacterial antioxidant defence system resulting in the increase of peroxidase (POD) and superoxide dismutase (SOD). ROS levels exceed its capacity, causing damage to the defence system and further oxidative decomposition of large molecules, such as DNA and proteins, eventually leading to the death of E. coli O157:H7. We also found the curcumin/chitosan coating could effectively remove E. coli O157:H7 biofilms by oxidative of extracellular polysaccharides and proteins. All the contributors made the chitosan/curcumin coating an efficient detergent comparable with HClO.


Assuntos
Antibacterianos , Biofilmes , Quitosana , Curcumina , Escherichia coli O157 , Fármacos Fotossensibilizantes , Espécies Reativas de Oxigênio , Quitosana/química , Quitosana/farmacologia , Curcumina/farmacologia , Curcumina/química , Escherichia coli O157/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Antibacterianos/farmacologia , Antibacterianos/química , Espécies Reativas de Oxigênio/metabolismo , Biofilmes/efeitos dos fármacos , Microbiologia de Alimentos , Luz
16.
Opt Lett ; 49(9): 2461-2464, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691744

RESUMO

Flicker electroretinography (ERG) has served as a valuable noninvasive objective tool for investigating retinal physiological function through the measurement of electrical signals originating from retinal neurons in response to temporally modulated light stimulation. Deficits in the response at certain frequencies can be used as effective biomarkers of cone-pathway dysfunction. In this Letter, we present the progress we made on its optical counterpart-photopic flicker optoretinography (f-ORG). Specifically, we focus on the measurement of the response of light-adapted retinal photoreceptors to a flicker stimulus with chirped frequency modulation. In contrast to measurements performed at discrete frequencies, this technique enables a significantly accelerated characterization of photoreceptor outer segment optical path length modulation amplitudes in the nanometer range as a function of stimulus frequency, enabling the acquisition of the characteristic frequency response in less than 2 sec.


Assuntos
Eletrorretinografia , Humanos , Eletrorretinografia/métodos , Luz , Estimulação Luminosa , Células Fotorreceptoras de Vertebrados/fisiologia
17.
Physiol Plant ; 176(3): e14327, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716559

RESUMO

Our goal was to determine whether anthocyanin-producing species (red) use different photoprotective strategies to cope with excess light during fall senescence compared with non-anthocyanin-producing species (yellow). In a previous study, we found that a yellow species retained the photoprotective PsbS protein in late autumn, while a red species did not. Specifically, we tested the hypothesis that red species make less use of zeaxanthin and PsbS-mediated thermal dissipation, as they rely on anthocyanins for photoprotection. We monitored four red (Acer ginnala, Rhus typhnia, Parenthocissus quinquefolia, Viburnum dentatum) and four yellow species (Acer negundo, Ostrya virginiana, Vitis riparia, Zanthoxylum americanum) throughout autumn senescence and analyzed pigments, protein content, and chlorophyll fluorescence. We found yellow species retained the PsbS protein at higher levels, and had higher dark retention of zeaxanthin in late autumn relative to red species. All species retained lutein and the pool of xanthophyll cycle pigments in higher amounts than other carotenoids in late autumn. Our data support the hypothesis that red species use anthocyanins as a photoprotective strategy during autumn senescence, and therefore make less use of PsbS and zeaxanthin-mediated thermal dissipation. We also found species-specific variation in the particular combination of photoprotective strategies used.


Assuntos
Antocianinas , Clorofila , Folhas de Planta , Estações do Ano , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Folhas de Planta/fisiologia , Antocianinas/metabolismo , Clorofila/metabolismo , Senescência Vegetal , Zeaxantinas/metabolismo , Carotenoides/metabolismo , Luz , Proteínas de Plantas/metabolismo , Xantofilas/metabolismo
18.
Arq Bras Oftalmol ; 87(3): e20230257, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716966

RESUMO

PURPOSE: This review emphasizes the effect of light on visual efficiency, the impact of different lighting focuses, types of lighting, and their influence on vision and productivity. Light sources and standards are intriguing subjects for ophthalmologists. Guidelines regarding the level of lighting influence on visual activities can enhance visual performance.Methods: This article was developed based on literature reviews, with a bibliographic survey conducted in databases such as PubMed, MEDLINE, Web of Science, Embase, LILACS, and SciELO. RESULTS: Provides recommendations for understanding information regarding the influence of lighting on visual performance. CONCLUSION: Proper workplace lighting is crucial for improving visual efficiency, safety, productivity, and worker health. Efficient workplace lighting should avoid light sources directed towards the worker's face, prevent harmful glare, be more intense in the work area, and uniform in the rest of the room. Ophthalmologists should be knowledgeable about and provide guidance on correct lighting to ensure patient comfort and satisfaction with visual correction.


Assuntos
Iluminação , Humanos , Visão Ocular/fisiologia , Acuidade Visual/fisiologia , Local de Trabalho , Saúde Ocupacional , Ofuscação , Luz
19.
Sci Rep ; 14(1): 10183, 2024 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702452

RESUMO

The perception of halos and other night vision disturbances is a common complaint in clinical practice. Such visual disturbances must be assessed in order to fully characterize each patient's visual performance, which is particularly relevant when carrying out a range of daily tasks. Visual problems are usually assessed using achromatic stimuli, yet the stimuli encountered in daily life have very different chromaticities. Hence, it is important to assess the effect of the chromaticity of visual stimuli on night vision disturbances. The aim of this work is to study the influence of the chromaticity of different visual stimuli on night vision disturbances by analyzing straylight and visual discrimination under low-light conditions. For that, we assessed the monocular and binocular visual discrimination of 27 subjects under low illumination using the Halo test. The subjects' visual discrimination was assessed after exposure to different visual stimuli: achromatic, red, green, and blue, both at the monitor's maximum luminance and maintaining the same luminance value for the different visual stimuli. Monocular straylight was also measured for an achromatic, red, green, and blue stimuli. The blue stimulus had the greatest effect on halos in both monocular and binocular conditions. Visual discrimination was similar for the red, green, and achromatic stimuli, but worsened at lower luminance. The greatest influence of straylight was observed for the blue stimulus. In addition, visual discrimination correlated with straylight measurements for achromatic stimuli, wherein greater straylight values correlated with an increased perception of halos and other visual disturbances.


Assuntos
Estimulação Luminosa , Humanos , Masculino , Feminino , Adulto , Visão Noturna/fisiologia , Adulto Jovem , Luz , Visão Binocular/fisiologia , Percepção Visual/fisiologia , Percepção de Cores/fisiologia , Transtornos da Visão/fisiopatologia , Iluminação , Pessoa de Meia-Idade
20.
J Am Chem Soc ; 146(19): 13317-13325, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38700457

RESUMO

We describe the synthesis and biological testing of ruthenium-bipyridine ruxolitinib (RuBiRuxo), a photoreleasable form of ruxolitinib, a JAK inhibitor used as an antitumoral agent in cutaneous T-cell lymphomas (CTCL). This novel caged compound is synthesized efficiently, is stable in aqueous solution at room temperature, and is photoreleased rapidly by visible light. Irradiation of RuBiRuxo reduces cell proliferation and induces apoptosis in a light- and time-dependent manner in a CTCL cell line. This effect is specific and is mediated by a decreased phosphorylation of STAT proteins. Our results demonstrate the potential of ruthenium-based photocompounds and light-based therapeutic approaches for the potential treatment of cutaneous lymphomas and other pathologies.


Assuntos
Antineoplásicos , Apoptose , Proliferação de Células , Nitrilas , Pirazóis , Pirimidinas , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Nitrilas/química , Nitrilas/farmacologia , Nitrilas/síntese química , Pirimidinas/química , Pirimidinas/farmacologia , Pirimidinas/síntese química , Apoptose/efeitos dos fármacos , Pirazóis/farmacologia , Pirazóis/química , Pirazóis/síntese química , Linhagem Celular Tumoral , Inibidores de Janus Quinases/farmacologia , Inibidores de Janus Quinases/química , Inibidores de Janus Quinases/síntese química , Rutênio/química , Rutênio/farmacologia , Luz , Estrutura Molecular , Janus Quinases/antagonistas & inibidores , Janus Quinases/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA