Photochemical & Photobiological Sciences最新文献

This experiment investigated the effects of an ecologically relevant level of dim light at night (dLAN) on behavior, physiology and fat metabolism associated gene expressions in central and peripheral tissues of adult male zebra finches that were hatched and raised in 12:12 h LD cycle (Ev, day = 150 ± 5 lx; Ev, night = 0 lx) at 22 ± 2 °C temperature. Half of the birds (n = 8) were maintained on LD cycle and temperature, as before (control), to the other half of birds the 12 h dark period was dimly illuminated at ~ 5 lx (dim light at night, dLAN; Ev, day = 150 ± 5 lx; Ev, night =  ~ 5 lx) for 6 weeks. The exposure to dLAN altered the 24 h activity and feeding patterns with enhanced activity and feeding at night. Birds under dLAN fattened and gained weight, and had higher night glucose levels. Concurrently, a negative effect of dLAN was found on mRNA expression of ppar-alpha and cd36 genes involved in the fat metabolism in the hypothalamus, intestine, liver and muscle. These results suggest a more global effect of dLAN exposure on obesity and perhaps long-term health risks due to obesity-related complications to diurnal animals including humans inhabiting an urbanized environment.

The modeling of the bioluminescent system of fireflies is key to understand the binding mode of the oxyluciferin/luciferase complex and its photophysical properties with the aim of developing high-efficiency devices and techniques. In this work, we present the OLUFF force field, which is able to describe the interactions to sample the conformational space of the four possible oxyluciferin emitters in both ground and excited state. This force field has been parameterized to reproduce quantum mechanical (QM) energies and geometrical parameters. Moreover, it has been validated by comparing probability distribution functions, minimized structures, infrared spectra and normal mode analysis obtained from OLUFF-based molecular dynamic (MD) simulations with their QM counterparts. Additionally, ground state simulations have also been performed using the general amber force field (GAFF) and compared with the OLUFF. It has been demonstrated that the OLUFF not only reproduces well the QM properties, but also improves the results from the GAFF.

Phthalides represent a notable category of secondary metabolites that are prevalent in various plant species, certain fungi, and liverworts. The significant pharmacological properties of these compounds have led to the synthesis of a novel phthalide derivative. The current study focuses on investigating the binding interactions of a newly synthesized 3-substituted phthalide derivative, specifically 3-((4-chloro-6-methyl pyrimidine-2-yl)amino) isobenzofuran-1(3H)-one (Z11), with double-stranded deoxyribonucleic acid (dsDNA). Research in the pharmaceutical and biological fields aimed at developing more potent DNA-binding agents must take into account the mechanisms by which these newly synthesized compounds interact with DNA. This investigation seeks to explore the binding dynamics between dsDNA and our compound through a variety of analytical techniques, such as electrochemistry, UV spectroscopy, fluorescence spectroscopy, and thermal denaturation. The binding constant (K_b) of Z11 with DNA was determined using both spectroscopic and voltammetric approaches. The research revealed that Z11 employs a groove binding mechanism to associate with dsDNA. To further explore the interactions between Z11 and dsDNA, the study utilized density functional theory (DFT) calculations, molecular docking, and molecular dynamics simulations. These analyses aimed to ascertain the potential for a stable complex formation between Z11 and dsDNA. The results indicate that Z11 is situated within the minor groove of the dsDNA, demonstrating the ability to establish a stable complex. Furthermore, the findings imply that both π-alkyl interactions and hydrogen bonding play significant roles in the stabilization of this complex.

Hidradenitis suppurativa is a chronic skin disorder characterized by painful inflammatory nodules and abscesses, significantly impacting patients' quality of life. Current treatment strategies, including topical antibiotics, often yield limited efficacy and pose risks of antibiotic resistance. Photodynamic therapy has emerged as a potential option, with RLP068/Cl (ELKOFAST®, non-sterile formulation) showing promising efficacy due to its broad-spectrum bactericidal activity. We conducted a pilot study assessing the therapeutic response to photodynamic therapy with RLP068/Cl versus topical clindamycin gel in patients affected by hidradenitis suppurativa of Hurley score I, II, and III. Results revealed higher efficacy of photodynamic therapy in combination with RLP068/Cl, particularly in mild cases. Its efficacy remains reliable even in more severe cases when combined with adalimumab. The observed faster lesion improvement and pain relief were ascribed to the bactericidal effects of RLP068/Cl against Gram⁺ and Gram^- bacteria. Furthermore, photoactivated RLP068/Cl was well tolerated with no adverse events reported. Therefore, photodynamic therapy following RLP068/Cl application represents a novel therapeutic option for hidradenitis suppurativa with potential implications for antibiotic stewardship in dermatology.

Due to the widespread use and incorrect handling of plastics, we need to find a practical and effective way to eliminate plastic waste from the environment. Different metal-doped nickel oxide (DMD-NiO) nanoparticles (NPs) were synthesized using a sol-gel technique and were used to degrade low-density polyethylene (LDPE) microplastic (MP) films when exposed to sunlight. The optical and structural properties of sol-gel method synthesized materials were investigated using a variety of characterization methods (Fourier transform infrared (FT-IR), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), X-ray diffractometer (XRD) analysis, X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, and thermogravimetric analysis (TGA). Degradation study results suggest that the photocatalytic activity of DMD-NiO-LDPE nanocomposites (NCs) films was greater than that of pure LDPE and undoped NiO-LDPE films. Because of their increased optical absorption and efficient suppression of photo-produced charge carriers' recombination, the DMD-NiO NPs showed higher photocatalytic degradation of LDPE films. Thus, LDPE films with 2% wt Fe-NiO (iron-doped nickel oxide) nanomaterials showed a degradation of around 38.16% among DMD-NiO-LDPE NCs films under visible light over a short period of 30 days (240 h). The formation of carbonyl groups in the degradation product of LDPE was confirmed by Fourier transform infrared (FT-IR) analysis. When compared to the original LDPE film, the Fe-NiO-LDPE NCs films showed a significant decrease in crystallinity and carbonyl indexes, as much as 8.4% lower. The current project proposes the development of eco-friendly photocatalysts using a sol-gel technique for combating MP pollution in the environment.