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1.
Trop Anim Health Prod ; 56(4): 146, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38722408

RESUMEN

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.


Asunto(s)
Crianza de Animales Domésticos , Pollos , Iluminación , Animales , Pollos/crecimiento & desarrollo , Pollos/fisiología , Embrión de Pollo/crecimiento & desarrollo , Crianza de Animales Domésticos/métodos , Distribución Aleatoria , Femenino , Luz
2.
Methods Mol Biol ; 2808: 35-56, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38743361

RESUMEN

Mononegaviruses are promising tools as oncolytic and transgene vectors for gene therapy and regenerative medicine. However, when mononegaviruses are used for therapeutic applications, the viral activity must be strictly controlled due to concerns about toxicity and severe side effects. With this technology, mononegavirus vectors can be grown where they are intended and can be easily removed when they are no longer needed. In particular, a photoswitch protein called Magnet (consisting of two magnet domains) is incorporated into the hinge region between the connector and methyltransferase domains of the mononegavirus polymerase protein (L protein) to disrupt the L protein functions. Blue light (470 ± 20 nm) irradiation causes the dimerization of the two magnet domains, and the L protein is restored to activity, allowing viral gene expression and virus replication. Since the magnet domains' dimerization is reversible, viral gene expression and replication cease when blue light irradiation is stopped.


Asunto(s)
Regulación Viral de la Expresión Génica , Replicación Viral , Replicación Viral/genética , Humanos , Proteínas Virales/genética , Proteínas Virales/metabolismo , Luz , Animales , Vectores Genéticos/genética
3.
Molecules ; 29(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38731451

RESUMEN

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.


Asunto(s)
Dendrímeros , Pruebas de Sensibilidad Microbiana , Naftalimidas , Poliaminas , Naftalimidas/química , Naftalimidas/farmacología , Dendrímeros/química , Dendrímeros/farmacología , Poliaminas/química , Poliaminas/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Fluorescencia , Pseudomonas aeruginosa/efectos de los fármacos , Concentración de Iones de Hidrógeno , Bacillus cereus/efectos de los fármacos , Luz , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia
4.
Molecules ; 29(9)2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38731636

RESUMEN

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.


Asunto(s)
Flavonoides , Luz , Brotes de la Planta , Ácido Quínico , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismo , Brotes de la Planta/química , Ácido Quínico/análogos & derivados , Ácido Quínico/metabolismo , Ácido Quínico/química , Flavonoides/metabolismo , Flavonoides/química , Ácidos Indolacéticos/metabolismo
5.
Sci Rep ; 14(1): 10566, 2024 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719873

RESUMEN

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.


Asunto(s)
Amoxicilina , Antibacterianos , Luz , Nanoestructuras , Catálisis , Antibacterianos/química , Nanoestructuras/química , Amoxicilina/química , Contaminantes Químicos del Agua/química , Cobre/química , Óxido de Zinc/química , Dióxido de Silicio/química , Purificación del Agua/métodos
6.
Food Res Int ; 186: 114382, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729736

RESUMEN

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.


Asunto(s)
Antocianinas , Daucus carota , Luz , Antocianinas/química , Antocianinas/análisis , Acilación , Daucus carota/química , Daucus carota/efectos de la radiación , Cromatografía Líquida de Alta Presión , Oscuridad , Almacenamiento de Alimentos/métodos , Espectrometría de Masas , Concentración de Iones de Hidrógeno
7.
J Am Chem Soc ; 146(19): 13317-13325, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38700457

RESUMEN

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.


Asunto(s)
Antineoplásicos , Apoptosis , Proliferación Celular , Nitrilos , Pirazoles , Pirimidinas , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Proliferación Celular/efectos de los fármacos , Nitrilos/química , Nitrilos/farmacología , Nitrilos/síntesis química , Pirimidinas/química , Pirimidinas/farmacología , Pirimidinas/síntesis química , Apoptosis/efectos de los fármacos , Pirazoles/farmacología , Pirazoles/química , Pirazoles/síntesis química , Línea Celular Tumoral , Inhibidores de las Cinasas Janus/farmacología , Inhibidores de las Cinasas Janus/química , Inhibidores de las Cinasas Janus/síntesis química , Rutenio/química , Rutenio/farmacología , Luz , Estructura Molecular , Quinasas Janus/antagonistas & inhibidores , Quinasas Janus/metabolismo
8.
Luminescence ; 39(5): e4768, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38719590

RESUMEN

In this study, we synthesize nanostructured nickel oxide (NiO) and doped cobalt (Co) by combining nickel(II) chloride hexahydrate (NiCl2.6H2O) and sodium hydroxide (NaOH) as initial substances. We analyzed the characteristics of the product nanostructures, including their structure, optical properties, and magnetic properties, using various techniques such as x-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet absorption spectroscopy (UV-Vis), Fourier transform infrared (FTIR) spectroscopy, and vibrating sample magnetometers (VSM). The NiO nanoparticles doped with Co showed photocatalytic activity in degrading methylene blue (MB) dye in aqueous solutions. We calculated the degradation efficiencies by analyzing the UV-Vis absorption spectra at the dye's absorption wavelength of 664 nm. It was observed that the NiO-doped Co nanoparticles facilitated enhanced recombination and migration of active elements, which led to more effective degradation of organic dyes during photocatalysis. We also assessed the electrochemical properties of the materials using cyclic voltammetry (CV) and impedance spectroscopy in a 1 mol% NaOH solution. The NiO-modified electrode exhibited poor voltammogram performance due to insufficient contact between nanoparticles and the electrolyte solution. In contrast, the uncapped NiO's oxidation and reduction cyclic voltammograms displayed redox peaks at 0.36 and 0.30 V, respectively.


Asunto(s)
Cobalto , Electroquímica , Electrodos , Nanocompuestos , Níquel , Nanocompuestos/química , Níquel/química , Cobalto/química , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Luminiscencia , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Fenómenos Magnéticos , Nanopartículas/química , Luz , Catálisis , Óxidos/química , Azul de Metileno/metabolismo
9.
ACS Appl Mater Interfaces ; 16(19): 24410-24420, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709954

RESUMEN

Sonophotodynamic antimicrobial therapy (SPDAT) is recognized as a highly efficient biomedical treatment option, known for its versatility and remarkable healing outcomes. Nevertheless, there is a scarcity of sonophotosensitizers that demonstrate both low cytotoxicity and exceptional antibacterial effectiveness in clinical applications. In this paper, a novel ZnO nanowires (NWs)@TiO2-xNy core-sheath composite was developed, which integrates the piezoelectric effect and heterojunction to build dual built-in electric fields. Remarkably, it showed superb antibacterial effectiveness (achieving 95% within 60 min against S. aureus and ∼100% within 40 min against E. coli, respectively) when exposed to visible light and ultrasound. Due to the continuous interference caused by light and ultrasound, the material's electrostatic equilibrium gets disrupted. The modification in electrical properties facilitates the composite's ability to attract bacterial cells through electrostatic forces. Moreover, Zn-O-Ti and Zn-N-Ti bonds formed at the interface of ZnO NWs@TiO2-xNy, further enhancing the dual internal electric fields to accelerate the excited carrier separation to generate more reactive oxygen species (ROS), and thereby boosting the antimicrobial performance. In addition, the TiO2 layer limited Zn2+ dissolution into solution, leading to good biocompatibility and low cytotoxicity. Lastly, we suggest a mechanistic model to offer practical direction for the future development of antibacterial agents that are both low in toxicity and high in efficacy. In comparison to the traditional photodynamic therapy systems, ZnO NWs@TiO2-xNy composites exhibit super piezo-photocatalytic antibacterial activity with low toxicity, which shows great potential for clinical application as an antibacterial nanomaterial.


Asunto(s)
Antibacterianos , Escherichia coli , Nanocables , Staphylococcus aureus , Titanio , Óxido de Zinc , Titanio/química , Titanio/farmacología , Titanio/efectos de la radiación , Óxido de Zinc/química , Óxido de Zinc/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Nanocables/química , Catálisis , Especies Reactivas de Oxígeno/metabolismo , Pruebas de Sensibilidad Microbiana , Humanos , Luz , Ratones , Animales
10.
PLoS One ; 19(5): e0304086, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38771849

RESUMEN

Recently, the first generic glucagon for injection was approved for the treatment of severe hypoglycemia. Unlike its brand name recombinant glucagon, the generic glucagon is synthetic. Since glucagon has a high propensity to form aggregates in solution, it is essential to assess the aggregation profile of the synthetic glucagon compared to the recombinant glucagon. In this study, two robust separation methods, size-exclusion chromatography (SEC-HPLC) and field-flow fractionation coupled with a multi-angle light scattering detector (FFF-MALS), were employed to characterize generic and brand glucagon aggregation in six lots (three newly released, three expired). The presence of aggregation in samples was determined from the generated chromatograms and analyzed. The study showed that both products have comparable aggregation profiles. The SEC-HPLC demonstrated that in both glucagon versions, the expired lots had a higher percentage of dimers than the newly released lots, but even at expiration, the amount was negligible (∼0.1%). The FFF-MALS method did not detect any dimers or higher molecular weight aggregates. Further evaluation of the detection limit found that FFF-MALS was unable to detect aggregates at amounts lower than 0.5% of total glucagon. The negligible amounts of dimer detected in the generic and brand glucagon indicate that both versions are physically stable and are not prone to aggregation under clinically relevant conditions.


Asunto(s)
Cromatografía en Gel , Glucagón , Agregado de Proteínas , Glucagón/química , Glucagón/análisis , Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Gel/métodos , Dispersión de Radiación , Humanos , Luz
11.
Curr Biol ; 34(10): R507-R509, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38772340

RESUMEN

Arbuscular mycorrhiza, an ancient symbiosis with soil fungi, support mineral nutrition in most plants. How roots recognize such symbiotic fungi has long been debated. Recent research identifies a Medicago truncatula receptor as a key player in triggering symbiont accommodation responses.


Asunto(s)
Medicago truncatula , Micorrizas , Simbiosis , Simbiosis/fisiología , Medicago truncatula/microbiología , Medicago truncatula/metabolismo , Medicago truncatula/fisiología , Micorrizas/fisiología , Raíces de Plantas/microbiología , Raíces de Plantas/metabolismo , Luz , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Luz Verde
12.
Int J Mol Sci ; 25(9)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38732166

RESUMEN

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.


Asunto(s)
Bismuto , Fotólisis , Rodaminas , Catálisis , Bismuto/química , Rodaminas/química , Luz , Compuestos Férricos/química , Compuestos de Nitrógeno/química , Titanio/química , Procesos Fotoquímicos , Nitrilos/química , Cinética , Grafito , Óxidos , Compuestos de Calcio
13.
Int J Mol Sci ; 25(9)2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38732247

RESUMEN

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.


Asunto(s)
Frutas , Regulación de la Expresión Génica de las Plantas , Fotosíntesis , Proteínas de Plantas , Azúcares , Vitis , Vitis/genética , Vitis/metabolismo , Vitis/efectos de la radiación , Frutas/genética , Frutas/metabolismo , Frutas/efectos de la radiación , Fotosíntesis/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Azúcares/metabolismo , Luz
14.
Physiol Plant ; 176(3): e14339, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38736185

RESUMEN

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.


Asunto(s)
Caulerpa , Fenotipo , Transcriptoma , Transcriptoma/genética , Caulerpa/genética , Caulerpa/fisiología , Luz , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión Génica
15.
Colloids Surf B Biointerfaces ; 238: 113923, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38692173

RESUMEN

The rapid advancement of photodynamic therapy (PDT) antibacterial materials has led to promising alternatives to antibiotics for treating bacterial infections. However, antibacterial drugs have poor light absorption and utilization rates, which limits their practical application. Constructing two-dimensional (2D) heterojunctions from materials with matching photophysical properties has emerged as a highly effective strategy for achieving high-efficiency photo-antibacterial performance. Here, we designed and prepared an atom co-sharing Bi/Bi4O5Br2 nanosheet heterojunction by a simple in situ reduction. This heterojunction material combines outstanding biocompatibility with excellent bactericidal efficiency, which exceeded 90 % against Escherichia coli (a Gram-negative bacterium) and Staphylococcus aureus (a Gram-positive bacterium) under visible light irradiation, around nine-fold higher than that with pure Bi4O5Br2 nanosheets. The results suggest that localized surface plasmon resonance (LSPR) of shared Bi atoms on the Bi4O5Br2 nanosheets promotes light utilization and the separation and transfer of photo-generated charges, thus producing more abundant reactive oxygen species (ROS), which can partake in the PDT antibacterial effect. Our study underscores the potential utility of LSPR-enhanced Bi-based nanosheet heterojunctions for safe and efficient PDT to combat bacterial infections.


Asunto(s)
Antibacterianos , Bismuto , Escherichia coli , Luz , Nanoestructuras , Staphylococcus aureus , Antibacterianos/farmacología , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Nanoestructuras/química , Bismuto/química , Bismuto/farmacología , Catálisis , Pruebas de Sensibilidad Microbiana , Procesos Fotoquímicos , Especies Reactivas de Oxígeno/metabolismo , Resonancia por Plasmón de Superficie , Fotoquimioterapia , Tamaño de la Partícula
16.
J Photochem Photobiol B ; 255: 112925, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703451

RESUMEN

Visible light triggers free radical production in alive and intact Drosophila melanogaster. We exposed fruit flies to red (613-631 nm), green (515-535 nm), and blue (455-475 nm) light while we monitored changes in unpaired electron content with an electron spin resonance spectrometer (ESR/EPR). The immediate response to light is a rapid increase in spin content lasting approximately 10 s followed by a slower, linear increase for approximately 170 s. When the light is turned off, the spin population promptly decays with a similar time course, though never fully returning to baseline. The magnitude and time course of the spin production depends on the wavelength of the light. Initially, we surmised that eumelanin might be responsible for the spin change because of its documented ability for visible light absorption and its highly stable free radical content. To explore this, we utilized different fruit fly strains with varying eumelanin content and clarified the relation of melanin types with the spin response. Our findings revealed that flies with darker cuticle have at least three-fold more unpaired electrons than flies with yellow cuticle. However, to our surprise, the increase in unpaired electron population by light was not drastically different amongst the genotypes. This suggests that light-induced free radical production may not exclusively rely on the presence of black melanin, but may instead be dependent on light effects on quinone-based cuticular polymers.


Asunto(s)
Drosophila melanogaster , Luz , Melaninas , Animales , Radicales Libres/química , Drosophila melanogaster/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Melaninas/química , Melaninas/metabolismo , Melaninas/biosíntesis
17.
Sci Rep ; 14(1): 11642, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773346

RESUMEN

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.


Asunto(s)
Luz , Optogenética , Células Ganglionares de la Retina , Optogenética/métodos , Células Ganglionares de la Retina/fisiología , Células Ganglionares de la Retina/efectos de la radiación , Humanos , Mutación , Animales , Opsinas/genética , Opsinas/metabolismo , Visión Ocular/fisiología
18.
FEMS Microbiol Ecol ; 100(6)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38702847

RESUMEN

Sandy sediments of lowland streams are transported as migrating ripples. Benthic microorganisms colonizing sandy grains are exposed to frequent moving-resting cycles and are believed to be shaped by two dominant environmental factors: mechanical stress during the moving phase causing biofilm abrasion, and alternating light-dark cycles during the resting phase. Our study consisted of two laboratory experiments and aimed to decipher which environmental factor causes the previously observed hampered sediment-associated microbial activity and altered community structure during ripple migration. The first experiment tested the effect of three different migration velocities under comparable light conditions. The second experiment compared migrating and stationary sediments under either constant light exposure or light oscillation. We hypothesized that microbial activity and community structure would be more strongly affected by (1) higher compared to lower migration velocities, and by (2) light oscillation compared to mechanical stress. Combining the results from both experiments, we observed lower microbial activity and an altered community structure in sediments exposed to light oscillation, whereas migration velocity had less impact on community activity and structure. Our findings indicate that light oscillation is the predominating environmental factor acting during ripple migration, resulting in an increased vulnerability of light-dependent photoautotrophs and a possible shift toward heterotrophy.


Asunto(s)
Sedimentos Geológicos , Luz , Sedimentos Geológicos/microbiología , Bacterias/efectos de la radiación , Bacterias/crecimiento & desarrollo , Bacterias/genética , Microbiota , Ríos/microbiología , Estrés Mecánico , Biopelículas/crecimiento & desarrollo , Biopelículas/efectos de la radiación
20.
Nature ; 629(8012): 586-591, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720080

RESUMEN

Light-emitting diodes (LEDs) based on perovskite quantum dots (QDs) have produced external quantum efficiencies (EQEs) of more than 25% with narrowband emission1,2, but these LEDs have limited operating lifetimes. We posit that poor long-range ordering in perovskite QD films-variations in dot size, surface ligand density and dot-to-dot stacking-inhibits carrier injection, resulting in inferior operating stability because of the large bias required to produce emission in these LEDs. Here we report a chemical treatment to improve the long-range order of perovskite QD films: the diffraction intensity from the repeating QD units increases three-fold compared with that of controls. We achieve this using a synergistic dual-ligand approach: an iodide-rich agent (aniline hydroiodide) for anion exchange and a chemically reactive agent (bromotrimethylsilane) that produces a strong acid that in situ dissolves smaller QDs to regulate size and more effectively removes less conductive ligands to enable compact, uniform and defect-free films. These films exhibit high conductivity (4 × 10-4 S m-1), which is 2.5-fold higher than that of the control, and represents the highest conductivity recorded so far among perovskite QDs. The high conductivity ensures efficient charge transportation, enabling red perovskite QD-LEDs that generate a luminance of 1,000 cd m-2 at a record-low voltage of 2.8 V. The EQE at this luminance is more than 20%. Furthermore, the stability of the operating device is 100 times better than previous red perovskite LEDs at EQEs of more than 20%.


Asunto(s)
Compuestos de Calcio , Óxidos , Puntos Cuánticos , Titanio , Puntos Cuánticos/química , Titanio/química , Compuestos de Calcio/química , Óxidos/química , Conductividad Eléctrica , Ligandos , Luz , Semiconductores
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