OGD/R‐induced ferroptosis and pyroptosis in retinal pigment epithelium cells: Role of PLD1 and PLD2 modulation

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Abstract

This study investigated the role of phospholipase D (PLD) in retinal ischemia–reperfusion (I/R) injury using an oxygen-glucose deprivation/reperfusion (OGD/R) model commonly used in retinal I/R injury research. To create an in vitro cellular I/R model, pharmacological inhibitors and small interfering RNA (siRNA) were used to target PLD1 and PLD2 in retinal pigment epithelial (RPE) cells. Treatment with PLD inhibitors and siRNA reduced reactive oxygen species (ROS) and malondialdehyde (MDA) induced by OGD/R in RPE cells and increased the levels of superoxide dismutase (SOD) and glutathione (GSH), indicating a reduction in oxidative damage and improvement in the antioxidant system. Next, we showed that inhibiting PLD1 or PLD2 reduced intracellular iron levels and lipid peroxidation, which are critical factors in ferroptosis. Additionally, PLD1 and PLD2 modulated the expression of proteins involved in the regulation of ferroptosis, including GPX4, SLC7A11, FTH1, and ACSL4. We also investigated the roles of PLD1 and PLD2 in preventing pyroptosis, another form of programmed cell death associated with inflammation. Our study found that OGD/R significantly increased the production of pro-inflammatory cytokines and activated caspase-1, NLRP3, ASC, cleaved-caspase 1 (C-caspase-1), and GSDMD-N in RPE cells, indicating pyroptosis induction. However, PLD1 and PLD2 inhibition or knockdown significantly inhibited the production of pro-inflammatory cytokines and activation of the NLRP3 inflammasome, Taken together, our findings support the hypothesis that the PLD signaling pathway plays a key role in OGD/R-induced ferroptosis and pyroptosis induction and may be a potential therapeutic target for preventing or treating retinal dysfunction and degeneration.

NMR Self‐Diffusion and Transverse Relaxation Time in Bitumen: The Effect of Aging.

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In this investigation the dynamics of two types of bitumens with different penetration grade were tested by using dynamic shear rheometry (DSR) and Nuclear Magnetic Resonance (NMR) at unaged conditions, and upon both short- and long-term artificial aging. The gel-sol transition temperature  was found to increase with increasing the time of aging treatment. Arrhenius parameters of the viscosity were found, unexpectedly, to be correlated with those of simple liquids, suggesting that the two kinds of systems, although chemically and physically quite different, share the same basic process at the molecular level. The molecular dynamics has been then investigated by NMR Pulsed Field Gradient Stimulated-Echo (PFGSE) and relaxometry (Carr-Purcell-Meiboom-Gill, CPMG, spin-echo pulse sequence) to capture the effect of aging upon dynamics variables such as self-diffusion coefficients D and transverse relaxation times T2. The translational diffusion at T >  of the light molecular components of both types of bitumens was characterized by broad distributions of D which were found independent of the experimental time scale up to 0.2 s. Similarly, T2 data could be described as a continuous unimodal distributions of relaxation times determined both at T <  and T > .

Copper chlorophyllin immobilized on ZrO2 nanoparticle as an effective and green catalyst in the one‐pot thioetherification reaction

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Copper chlorophyllin immobilized on ZrO2 nanoparticle as an effective and green catalyst in the one-pot thioetherification reaction

The CC@ZrO2 green catalyst was created by immobilizing a chlorophyllin copper complex onto ZrO2 nanoparticles under mechanical conditions. The resulting catalyst demonstrated exceptional efficacy in generating different types of thioether derivatives.


The synthesis of organosulfur compounds gained specific interest in the interference of organic chemistry and chemical biology. Copper chlorophyllin (CC) is a bio-based copper complex that facilitates the synthesis of organosulfur compounds through the thioetherification reaction. The current paper deals with the immobilization of CC on the ZrO2 nanoparticles (CC@ZrO2) and its application in the one-pot thioetherification of alkyl and aryl halides using thiourea, an alternative to the bad-smelling thiols. After the characterization of CC@ZrO2 with different analytical techniques such as FT-IR, TGA, XPS, N2 adsorption/desorption, XRD, ICP, and FESEM, the catalytic activity of the prepared CC@ZrO2 was evaluated in the synthesis of different types of thioether derivatives. Good to excellent yields, high reusability, and reproducibility made this cost-effective approach a benchmark in C–S cross-coupling reactions.

Verbenone‐based push–pull chromophores with giant first hyperpolarizabilities: A new structure–property correlation study

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Verbenone-based push–pull chromophores with giant first hyperpolarizabilities: A new structure–property correlation study

Novel chromophores Ch1–8 based verbenone bridge were designed and systematically investigated using the BLA theory, two states model and SOS model. Chromophores Ch1–Ch8 exhibited distinct features in two-dimensional second order NLO responses, and the strong electro-optical Pockels effect and optical rectification responses.


Abstract

Novel chromophores Ch1–8 based verbenone bridge with various strong donors and acceptors were designed for applications in nonlinear optics, and the nonlinear optical (NLO) properties of those verbenone-type chromophores were systematically investigated using the bond length alteration (BLA) theory, two states model (TSM) and sum-over-states (SOS) model. The results show that several verbenone-based chromophores possess remarkably large molecular second-order hyperpolarizabilities, which is due to its electron distribution close to the cyanine limit, the appropriate strength of acceptor, rather large change in dipole moment and low excitation energy. Computed hyperpolarizability (β tot ) of Ch6 also approach an outstanding 2922 × 10−30 esu in TFE. The hyperpolarizability density analyses and two states model (TSM) were carried out to make a further insight into the origination of molecular nonlinearity of this unique system, suggesting that tuning structure of acceptor and polarity of the medium have great influence on the second-order nonlinear optical properties. More importantly, chromophores Ch1–Ch8 exhibited distinct features in two-dimensional second order NLO responses, and the strong electro-optical Pockels effect and optical rectification responses. The excellent electronic sum frequency generations (SFG) and difference frequency generations (DFG) effect are observed in these verbenone-type chromophores. These chromophores have a possibility to be appealing second-order nonlinear optical (NLO) materials, data storage materials and DSSCs materials from the standpoint of large β values, high LHE, and excellent two-dimensional second order NLO responses.

Alkaline Ni‐Zn Rechargeable Batteries for Sustainable Energy Storage: Battery Components, Deterioration Mechanisms, and Impact of Additives

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The demand for long-term, sustainable, and low-cost battery energy storage systems with high power delivery capabilities for stationary grid-scale energy storage, as well as the necessity for safe lithium-ion battery alternatives, has renewed interest in aqueous zinc-based rechargeable batteries. The Alkaline Ni-Zn rechargeable battery chemistry was identified as a promising technology for sustainable energy storage applications, albeit a considerable investment in academic research, it still fails to deliver the requisite performance. It is hampered by a relatively short-term electrode degradation, resulting in a decreased cycle life. Dendrite formation, parasitic hydrogen evolution, corrosion, passivation, and dynamic morphological growth are all challenging and interrelated possible degradation processes. This Review elaborates on the components of Ni-Zn batteries and their deterioration mechanisms, focusing on the influence of electrolyte additives as a cost-effective, simple, yet versatile approach for regulating these phenomena and extending the battery cycle life. Even though a great deal of effort has been dedicated to this subject, the challenges remain. This highlights that a breakthrough is to be expected, but it will necessitate not only an experimental approach, but also a theoretical and computational one, including artificial intelligence (AI) and machine learning (ML).

Molecular Docking‐Based Identification of Potential Natural Neuroprotective Molecules for Parkinson’s Disease

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Molecular Docking-Based Identification of Potential Natural Neuroprotective Molecules for Parkinson's Disease


Abstract

Background: Parkinson's disease (PD) is a common progressive neurodegenerative and the prevailing treatments are ineffective in the early stages of the disease. Therefore, other strategies must be devised to halt the steady decrease of dopaminergic neurons in the brain. In Parkinson's disease, a dysregulated ACE/Ang II/AT1R axis in the brain causes free radical damage, apoptosis, and neuronal destruction. Current PD treatments only alleviate symptoms and do not reverse the degradation mechanism of dopaminergic neurons. As a result, it is critical to discover alternate, dependable medicines for the treatment of Parkinson's disease. Method: In the present study, homology modelling of MAS receptor, in silico docking and molecular dynamic studies (MDS) were employed to determine the efficacy of flavonoids as MASR activators. Result: The flavonoids Pterosupin and Amentoflavone exhibited best binding and therefore, the stability of these complexes were evaluated with MDS studies. The Pterosupin-MASR complex demonstrated better stability, stronger interactions and minimal fluctuation than the Amentoflavone-MASR complex. Conclusion: The data from the present study indicated that the flavonoid Pterosupin possesses better binding, favourable pharmacokinetic properties and stability. However, subsequent in vitro and in vivo assessments are necessary to validate its efficacy.

Manganese‐catalyzed Dehydrogenation of Amido Alcohols through Liberation of Hydrogen for the Synthesis of Oxazoles

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Syntheses of important classes of (heterocyclic) com­pounds, the sustainable generation of hydrogen, and the use of abundantly available metals are highly desirable. We introduce here a catalytic oxazole synthesis. Our reaction is a regio selective, one-pot reaction and starts from esters and amino alcohols. Both are abundantly and diversely available and inexpensive starting materials. Hydrogen is liberated during the reaction and a molecular earth-abundant metal catalyst, a Mn(I) compound, mediates the reaction most effectively - and more ef­ficiently than Ir and Ru catalysts. None of the oxazole derivatives synthesized, except the screening substrate and an active ingredient of a drug (an application), have been reported in literature yet.

Fabrication of mesoporous CrTe supported on graphitic carbon nitride as an efficient electrocatalyst for water oxidation

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Fabrication of mesoporous CrTe supported on graphitic carbon nitride as an efficient electrocatalyst for water oxidation

The synthesized composite material shows lower overpotential of 187 mV as well as lower Tafel slope value than the individual materials. It also shows excellent stability, which makes it suitable as electrocatalyst for water splitting.


It is essential to produce oxygen evolution reaction (OER) electrocatalysts, which are active and enduring for water electrolyzers. In order to create the effective OER, new chromium telluride/graphitic carbon nitride (gCN/CrTe) is produced via simple hydrothermal method. In this case, catalyst super hydrophilic surface is developed by the addition of 10% gCN nanosheets that can optimize the revelation of active sites and encourage the mass dispersion. Due to the robust contact among CrTe and gCN, which causes a lattice strain and an increase in the electron density around Cr sites, regulating the bonding between the catalyst and chemical intermediates. The improved 10% gCN/CrTe nanocomposite offers not only a good endurance but also by the highest mass activity. The synthesized 10% gCN/CrTe electrocatalysts provided low overpotential around 187 mV for OER to achieve a current density of 10 mA/cm2 in alkaline media with 51.0 h of long durability. Paving the way for innovative applications, this will enable the manipulation of advanced materials' fundamental properties at the atomic scale.