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This study investigates the interaction between daphnetin and ovalbumin (OVA) as well as its potential to inhibit OVA fibrillation using both spectroscopic and computational analysis. A moderate binding affinity of 1 × 104M–1was observed between OVA and daphnetin, with a static quenched mechanism identified during the fluorescence quenching processes. Metal ions’ (Cu2+and Zn2+) presence led to an increase in the binding affinities of daphnetin toward OVA, mirroring a similar trend observed with the pH variation. Synchronous and 3D fluorescence studies indicated an increase in the polarity of the microenvironment surrounding the Trp residues during binding. Interestingly, circular dichroism and Fourier transform infrared studies showed a significant change in the secondary structure of OVA upon binding with daphnetin. The efficacy of daphnetin in inhibiting protein fibrillation was confirmed through thioflavin T and Congo Red binding assays along with fluorescence microscopic imaging analysis. The thermodynamic assessment showed positive ΔH° [+(29.34 ± 1.526) kJ mol–1] and ΔS° [+(181.726 ± 5.465) J mol–1] values, indicating the presence of the hydrophobic forces, while negative ΔG° signifies spontaneous binding interactions. These experimental findings were further correlated with computational analysis, revealing daphnetin dynamics within the binding site of OVA.

In order to better understand the bioavailability and biocompatibility of polyphenol-assisted surface-modified bioengineered nanoparticles in nanomedicine applications, here, we address a series of photophysical experiments to quantify the binding affinity of serum albumin toward polyphenol-capped gold nanoparticles. For this, two different gold nanoparticles (AuNPs) were synthesized via the green synthesis approach, where curcumin and turmeric extract act as reducing as well as capping agents. The size, surface charge, and surface plasmon bands of the AuNPs were highly affected by the adsorption of human serum albumin (HSA) during protein corona formation, which was investigated using dynamic light scattering (DLS), ξ-potential, ultraviolet–visible (UV–vis) spectroscopy, and transmission electron microscopy (TEM) measurements. Fluorescence-based methods, absorbance, and SERS experiments were carried out to evaluate the binding aspects of AuNPs with HSA. We found that the AuNPs show moderate binding affinity toward HSA (Kb∼ 104M–1), irrespective of the capping agents on the surface. Hydrophobic association, along with some contribution of electrostatic interaction, played a key role in the binding process. The binding interaction was more toward the subdomain IIA region of HSA, as indicated by the competitive displacement studies using site-specific binders (warfarin and flufenamic acid). Because of the large surface curvature of small-sized AuNPs, the secondary structural conformations of HSA were slightly altered, as revealed by circular dichroism (CD), Fourier transform infrared (FT-IR) spectroscopy, and surface-enhanced Raman scattering (SERS) measurements. Additionally, the findings of the binding interactions were re-evaluated using molecular dynamics (MD) simulation studies by determining the root-mean-square deviation (RMSD), root-mean-square fluctuation (RMSF), radius of gyration (Rg), and changes in the binding energy of HSA upon complexation with AuNPs. To determine the tentative evidence for pharmacokinetic administration, these biocompatible AuNPs were applied to inhibit the amyloid fibril formation of HSA and monitored by using the thioflavin T (ThT) assay, ANS fluorescence assay, fluorescence microscopic imaging, and FESEM. AuNPs were found to show better resistance toward fibrillation of the adsorbed protein.

In the event of a severe accident in Sodium Cooled Fast Reactors (SFR), the sodium combustion aerosols along with fission product aerosols would migrate to the environment through leak paths of the Reactor Containment Building (RCB) concrete wall under positive pressure. Understanding the characteristics of sodium aerosol transport through concrete leak paths is important as it governs the environmental source term. In this context, experiments are conducted to study the influence of various parameters like pressure, initial mass concentration, leak path diameter, humidity etc., on the transport and deposition of sodium aerosols in straight leak paths of concrete. The leak paths in concrete specimens are prepared by casting and the diameter of the leak path is measured using thermography technique. Aerosol transport experiments are conducted to measure the transported and plugged aerosol mass in the leak paths and corresponding plugging times. The values of differential pressure, aerosol concentration and relative humidity taken for the study are in the ranges 10–15 kPa, 0.65–3.04 g/m3and 30–90% respectively. These observations are numerically simulated using 1-Dimensional transport equation. The simulated values are compared with the experimental results and reasonable agreement among them is observed. From the safety assessment view of reactor, the approach presented here is conservative as it is with straight leak paths.

ABSTRACT Fly ash is used in concrete industry to reduce the amount of cement and to enhance the durability of concrete. Nuclear industry recently adopted fly ash concrete as a [...]

IDHwild-type (wt) grade 2/3 astrocytomas are a heterogenous group of tumors with disparate clinical and molecular profiles. cIMPACT-NOW recommendations incorporated in the new 2021 World Health Organization (WHO) Classification of Central Nervous System (CNS) Tumors urge minimal molecular criteria to identify a subset that has an aggressive clinical course similar to IDH-wt glioblastomas (GBMs). This paper describes the use of a panel of molecular markers to reclassify IDH-wt grade 2/3 diffuse astrocytic gliomas (DAGs) and study median overall survival concerning for to IDH-wt GBMs in the Indian cohort. IDH-wt astrocytic gliomas (grades 2, 3, and 4) confirmed by IDHR132H immunohistochemistry and IDH1/2gene sequencing, 1p/19q non–codeleted with no H3F3Amutations were included. TERTpromoter mutation by Sanger sequencing, epidermal growth factor receptor amplification, and whole chromosome 7 gain and chromosome 10 loss by fluorescence in situ hybridization was assessed and findings correlated with clinical and demographic profiles. The molecular profile of 53 IDH-wt DAGs (grade 2: 31, grade 3: 22) was analyzed. Eleven cases (grade 2: 8, grade 3: 3) (20.75%) were reclassified as IDH-wt GBMs, WHO grade 4 (TERTpromoter mutation in 17%, epidermal growth factor receptor amplification in 5.5%, and whole chromosome 7 gain and chromosome 10 loss in 2%). Molecular GBMs were predominantly frontal (54.5%) with a mean age of 36 years and median overall survival equivalent to IDH-wt GBMs (18 vs. 19 mo; P=0.235). Among grade 2/3 DAGs not harboring these alterations, significantly better survival was observed for grade 2 versus grade 3 DAGs (25 vs. 16 mo; P=0.002). Through the incorporation of a panel of molecular markers, a subset of IDH-wt grade 2 DAGs can be stratified into molecular grade 4 tumors with prognostic and therapeutic implications. However, IDH-wt grade 3 DAGs behave like GBMs irrespective of molecular profile.

ABSTRACT This study aims to investigate the crack growth behavior of plain and fly ash concretes with different curing periods during uniaxial compression testing using acoustic emission (AE) technique. Compressive [...]

Sal-like protein 4 (SALL4) is a C2H2 zinc finger transcription factor (TF) with two naturally occurring isoforms; SALL4A and SALL4B. It is typically detected in fetal tissues and silenced in most normal adult tissues. It is therefore intriguing that SALL4 is aberrantly re-expressed in about one-third of almost all primary human malignancies, presumably by demethylation dependent mechanisms. Direct evidence of the causative role of SALL4 in cancer has been demonstrated in SALL4 transgenic mice, which developed myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and/or liver tumors. Loss-of-function studies by SALL4 knock-down using shRNA showed cell growth inhibition and death in leukemias and solid tumors in culture and in in vivoxenotransplants.

We report a weak anisotropic ferromagnetic behavior in a purely organic molecule at room temperature, a property rarely reported in organic nanomaterials. The reported 1,2-bis(tritylthio)ethane, forming plate- and organic-flower-like morphologies at the nanolevel, is the first organic crystal with an inherent magnetic property at 300 and 2 K. However, at low temperatures, the magnetization value [Mmax(T) ∼ 116 emu/mol at 2 K] increases drastically at 3 orders higher compared to 300 K. Interestingly, the system exhibits strong anisotropy with an anisotropic constant, K1∼ 3.25 × 103erg/cc, and anisotropy field, HK∼ 3.25 kOe. Below 10 K, this system displays unusual temperature dependence of the coercive field [HC(T)] and remanence magnetization [MR(T)] with a hysteresis-peak anomaly (T* ∼ 10–15 K) due to the enhanced spin–orbit coupling. The maximum HCand MRat T* were HC= 220 Oe and MR∼ 12 emu/mol, respectively. Beyond T*, HC(T) and MR(T) drop continuously and become negligible as the measurement temperature approaches 300 K. Our results demonstrate that the triphenyl molecules can be further exploited for the design and synthesis of organic magnets for possible applications in spintronics and memory storage devices.

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