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It is essential to study the interactions between nanoparticles and proteins to better understand the biological interactions of nanoparticles. In this study, we studied the protein adsorption mode on the surface of Ag-doped TiO2 nanoparticles (NPs) using a model protein, bovine serum albumin (BSA). The mechanism of binding BSA to the Ag-doped TiO2 NPs was studied by applying fluorescence quenching, absorbance measurements, circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy techniques. The strong binding between BSA and Ag-doped TiO2 NPs was confirmed by a high value of binding constant (K = 2.65 × 105 L mol−1). We also studied the thermal stability of BSA in the presence of the Ag-doped TiO2 NPs. Thermodynamic parameters indicated that the adsorption of BSA on the Ag-doped TiO2 NPs was a spontaneous, natural and exothermic process. The effect of Ag-doped TiO2 NPs on the transportation function of BSA was also studied using a fluorescence spectroscopic technique. Fluorescence spectroscopic data suggested the existence of a strong interaction between BSA and the surface of the Ag-doped TiO2 NPs, which indicated that the binding affinities of some selected amino acids in BSA changed. This, in turn, clearly confirms that the Ag-doped TiO2 NPs affect the transportation capability of BSA in blood. [ABSTRACT FROM AUTHOR]

Elevated global pollution level is the prime reason that contributes to the onset of various harmful health diseases. The products of Biginelli reaction are enormously used in the pharmaceutical industry as they have antiviral, antibacterial, and calcium channel modulation abilities. This work reports a novel eosin Y sensitized boron graphitic carbon nitride (EY‐Ben‐g‐C3N4) as a photocatalyst that efficiently produced 3,4‐dihydropyrimidine‐2‐(1H)‐one by the Biginelli reaction of benzaldehyde, urea, and methyl acetoacetate. The photocatalyst EY‐Ben‐g‐C3N4 showed a successful generation of 3,4‐dihydropyrimidine‐2‐(1H)‐one (Biginelli product) in good yield via photocatalysis which is an eco‐friendly method and has facile operational process. In addition to the production of Biginelli products, the photocatalyst also showed a remarkable NADH regeneration of 81.18%. The incorporation of g‐C3N4 with boron helps increase the surface area and the incorporation of eosin Y which is an inexpensive and non‐toxic dye, and in Ben‐g‐C3N4, enhanced the light‐harvesting capacity of the photocatalyst. The production of 3,4‐dihydropyrimidine‐2‐(1H)‐one and NADH by the EY‐Ben‐g‐C3N4 photocatalyst is attributed to the requisite band gap, high molar absorbance, low rate of charge recombination, and increased capacity of the photocatalyst to harvest solar light energy. [ABSTRACT FROM AUTHOR]

Hemin is an important iron‐containing porphyrin that has important therapeutic properties to control the symptoms of porphyria attacks that include pain, high blood pressure, rapid heartbeat, mental changes, and so forth. Lysozyme has many applications, which include from therapeutic to preservation of foods. The interaction of hemin with an important model protein, hen egg white lysozyme (HEWL), has been observed in this study through hybrid in silico with biophysical studies. There was a strong 1:1 cooperative binding between hemin and HEWL, which was revealed from the strong quenching of the latter by the former. The binding was favored by the decrease in temperature, which is due to the involvement of static type of quenching mechanism in the interaction. Experimental analyses suggested that the major forces involved in the binding were polar ones, and there was an efficient energy transfer from the fluorophore to the ligand. The combination of far‐UV CD spectroscopy and Rayleigh light scattering experiments established that hemin has the strong tendency to unfold HEWL. An extensive molecular docking investigation involving 2000 docking runs recognized the preferred binding site of hemin within HEWL, and also suggested that apart from the polar forces, hydrophobic interactions have also played an important role in the binding. [ABSTRACT FROM AUTHOR]

Binary transition metal dichalcogenides (BTMDs) have attracted a lot of researchers to exploit their unique properties for different applications in various fields, mainly in energy and environment. Surprisingly, there are no attempts of utilizing BTMDs materials particularly nickel molybdenum selenide (NiMoSe2) as a catalyst support for organic transformations. Reusable catalysts are better alternatives to the transition metal‐free protocols for the synthesis of heterocyclic compounds. Herein, we report a NiMoSe2 BTMD catalyst with Lewis acidic (transition metal) and strongly basic (selenide) sites for the regioselective synthesis of 2,3,5‐tri(het)aryl‐pyrroles from β‐thioxoketone precursors. The present method is capable of giving the expected products in good to excellent yields (up to 80%). Different substituents like ester, cyano, alkyl, trifluoromethyl, methoxy, and halogens have shown tolerance under optimized reaction conditions. The recyclability and reusability of the catalyst was checked for five catalytic cycles without notable loss in reactivity. [ABSTRACT FROM AUTHOR]

Mechanical, thermal, and water absorption properties of banana fiber and sisal fiber-reinforced epoxy biocomposites were evaluated with and without cashew nut shell (CNS) filler, either separately, or as hybrid biocomposites. Bidirectional woven mats were used to make composites by compression molding. The CNS filler content was 5% to 10%. Adding CNS filler of up to 5% improved the mechanical and thermal properties. Further increases in filler content above the threshold value diminished their mechanical properties due to poor dispersion and increased porosity. The maximum tensile and flexural strength were found as 43 and 92 MPa. The highest impact strength was obtained with the hybrid biocomposites with 5% filler. This was attributed to the toughening effect of phenolic compounds in the CNS. In addition, the thermal stability of the biocomposites was influenced by filler content. The biocomposites exhibited varying water absorption capacities as the filler content increased with the water uptake. Scanning electron microscopy (SEM) images showed the microsurface of the fractured samples and their interfacial bonding, fiber pull-out, and fracture. However, increasing filler content in the biocomposite reduced the filler pull-out and led to fiber breakage. [ABSTRACT FROM AUTHOR]

A novel method for forming composite materials was investigated by incorporating activated carbon powder (ACP) as a reinforcing agent within a polylactic acid (PLA) matrix, utilizing the hand layup fabrication technique. The composite materials were synthesized by varying the weight percentages of the matrix and reinforcements, encompassing pure PLA as well as ratios of 90:10, 80:20, 70:30, 60:40, and 50:50. PLA is recognized for its biocompatibility and favorable thermomechanical properties, similar to conventional plastics. The incorporation of activated carbon powder, known for its remarkable aspect ratio, proved highly advantageous, yielding exceptional mechanical properties. Analysis revealed that the composite with a ratio of 90:10 wt% of carbon powder to PLA demonstrated significant improvements in tensile strength (26.8%), flexural strength (26.37%), impact strength (61.1%), compression strength (25%), and hardness (45.8%). Additionally, thermal analysis showed that the 90:10 wt% composite exhibited minimal weight loss and maximum heat flow sustainability at approximately 600 °C compared to other composite combinations. Morphological examination using field emission scanning electron microscopy unveiled a uniform distribution of activated carbon powder reinforcement within the matrix, actively contributing to the enhanced mechanical properties of the composite. [ABSTRACT FROM AUTHOR]

Novel Quinoline‐triazole hybrid derivatives (9 a–9 l) were designed and synthesized via click reaction methodology to develop lead compounds with good antibacterial and antifungal potency. Synthetic compounds have been characterized using 1H NMR, 13C NMR, and mass spectrum analysis. In‐vitro antibacterial activity against two gram‐positive and two gram‐negative strains and in‐vitro antifungal activity against three different strains were performed for the synthesized compounds. Compounds 9 a, 9 d, and 9 i exhibited potent inhibition activity against S. aureus ranging from MIC=12.5–50 μg/mL, and compounds 9 a, 9 c, 9 d, 9 e, 9 f, 9 j, and 9 l exhibited potent inhibition activity against C. albicans fungal strains ranging from MFC=250–500 μg/mL. Molecular docking study of C. albicans Sterol 14α‐demethylase (CYP51) protein (PDB ID:5TZ1) and S. aureus tyrosyl‐tRNA synthetase (PDB ID: 1JIJ) was performed to understand the mechanism of action through which these derivatives work. In silico studies of Hybrid 9 d demonstrated strong hydrogen bonding and π–π interactions with Tyr64, Phe233, and Phe228 in line with the co‐crystals SB‐239629 and VT1161 exhibiting favorable interactions that inhibits both bacterial and fungal strains. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is one of the leading causes of high mortality rates in women worldwide. Although advancements have been made in the design of therapeutic strategies and drug discovery, drug resistance remains one of the key challenges. One of the ways to overcome drug resistance is finding potential drug combinations since the efficacy of combined drugs is higher than their individual efficacies if the combination is a synergistic pair. Therefore, the current study uses a BC patient‐derived xenograft (PDX) dataset to evaluate the effects of various cancer drugs on breast cancer in vivo models. The drug effects are further validated by four machine learning models, namely Elastic Net, Least Absolute Shrinkage and Selection (LASSO), Support Vector Machine (SVM), Random Forests (RF), as well as exploring the shortlisted drugs in combination with paclitaxel, a baseline drug for enhanced efficacy on tumor volume reduction. Additionally, the study also shortlists the top 50 in vivo biomarkers correlated with the effects of the drugs. The outcomes could be significantly important for the design of an effective anti‐breast cancer therapy. [ABSTRACT FROM AUTHOR]

Geotechnical designs and analyses of earth structures and foundations exclusively involve the assessment and consideration of unsaturated soil shear strength. The laboratory testing equipment and methods for predicting the unsaturated soil shear strength are complicated and more expensive. The experimental program attempted to involve undrained triaxial and filter paper for evaluating the unsaturated soil shear strength of identically compacted clayey soil. This study undertakes a comparison of shear strength in clayey soil under undrained loads, examining both saturated and unsaturated conditions. A 60 kPa air entry suction value is the key point at which linearity between the unsaturated shear strength parameter Øb and effective friction Ø′ with 15° linear slopes turns to non-linearity. Unsaturated shear strength increased by 22.76% in optimally wet conditions, 52.68% in optimum conditions, and 77.81% in optimally dry conditions as compared to saturated shear strength. This study utilizes an artificial neural network (ANN) to predict clayey soil's unsaturated shear strength, finding that the optimal ANN configuration (2-5-1 topology, Levenberg–Marquard optimization, and logsig transfer function) achieved high reliability with a correlation coefficient (R) of 0.9289 and mean square error values of 2.22, 7.12, and 3.012 for training, testing, and validation, respectively. This experimental investigation improves our understanding of clayey soil shear strength and emphasizes the importance of saturation and moisture content in geotechnical assessments under undrained loading conditions. [ABSTRACT FROM AUTHOR]

α‐Cembrenediol exhibits a wide range of biological activities, including antibacterial, antitumor, and neuroprotective effects. However, knowledge of the absorption, transport, and release of α‐cembrenediol in drug metabolism within the body is currently limited. Therefore, we aimed to gain a comprehensive understanding of the in vivo transport, distribution, and elimination mechanisms of α‐cembrenediol and investigate the interaction between α‐cembrenediol and HSA. To this end, we utilized various methods including UV absorption spectroscopy, steady‐state fluorescence analysis, circular dichroism measurements, molecular docking studies, and molecular dynamics simulations. The results of the UV and fluorescence spectra clearly demonstrated that HSA interacts with α‐cembrenediol. Specifically, the fluorescence spectra results showed that at a temperature of 310 K, the fluorescence quenching constant (KSV) and binding constant (Kb) between HSA and α‐cembrenediol were determined to be 1.28 × 103 Lmol−1 and 218.27 Lmol−1, respectively. As the temperature was decreased from 310 K to 293 K, both KSV and Kb values increased, indicating the presence of a static quenching mechanism throughout the interaction process. Moreover, the results indicated the presence of a singular, specific binding site for α‐cembrenediol on HSA, as evidenced by an approximate count of one binding site at all three temperatures. Additionally, this binding process occurred spontaneously (ΔG < 0), with van der Waals interactions and hydrogen bonding as the primary driving forces (ΔH = −9.40 kJmol−1 and ΔS = −14.50 Jmol−1·K−1). The binding of α‐cembrenediol to Sudlow site I of HSA was confirmed through molecular docking, a combination of fluorescence probe substitution, and molecular dynamics simulation experiments. Moreover, the results demonstrated that α‐cembrenediol binding led to alterations in the structural conformation of HSA, as confirmed by three‐dimensional fluorescence, synchronous fluorescence, and circular dichroism spectra. This study offers crucial insights into the interaction between α‐cembrenediol and HSA, contributing to an improved understanding of the compound's pharmacokinetic properties. [ABSTRACT FROM AUTHOR]