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Cisplatin (CDDP) is a widely used chemotherapeutic agent that has remarkable antineoplastic effects. However, CDDP can cause severe acute kidney injury (AKI), which limits its clinical application. Agrimol B is the main active ingredient found in Agrimonia pilosa Ledeb and has a variety of pharmacological activities. The effect of agrimol B on CDDP-induced renal toxicity has not been determined. To investigate whether agrimol B has a protective effect against CDDP-induced AKI, we first identify Sirtuin 1 (Sirt1) as a critical target protein of agrimol B in regulating AKI through network pharmacology analysis. Subsequently, the AKI mouse model is induced by administering a single dose of CDDP via intraperitoneal injection. By detecting the serum urea nitrogen and creatinine levels, as well as the histopathological changes, we confirm that agrimol B effectively reduces CDDP-induced AKI. In addition, treatment with agrimol B counteracts the increase in renal malondialdehyde level and the decrease in superoxide dismutase (SOD), catalase and glutathione levels induced by CDDP. Moreover, western blot results reveal that agrimol B upregulates the expressions of Sirt1, SOD2, nuclear factor erythroid2-related factor 2, and downstream molecules, including heme oxygenase 1 and NAD(P)H quinone dehydrogenase 1. However, administration of the Sirt1 inhibitor EX527 abolishes the effects of agrimol B. Finally, we establish a tumor-bearing mouse model and find that agrimol B has a synergistic antitumor effect with CDDP. Overall, agrimol B attenuates CDDP-induced AKI by activating the Sirt1/Nrf2 signaling pathway to counteract oxidative stress, suggesting that this compound is a potential therapeutic agent for the treatment of CDDP-induced AKI.

The aim of this study was to investigate the protective effect of nicotinamide adenine dinucleotide ([NAD.sup.+]) against acute liver injury (ALI) induced by acetaminophen (APAP) overdose in mice. First, serum transaminases were used to assess the protective effect of [NAD.sup.+], and the data revealed that [NAD.sup.+] mitigated the APAP-induced ALI in a dose-dependent manner. Then, we performed hematoxylin-eosin staining of liver tissues and found that [NAD.sup.+] alleviated the abnormalities of histopathology. Meanwhile, increase in the malondialdehyde content and decrease in glutathione, superoxide dismutase (SOD), and glutathione peroxidase were identified in the APAP group, which were partially prevented by the [NAD.sup.+] pretreatment. Moreover, compared with the mice treated with APAP only, the expression of poly ADP-ribose polymerase 1 (PARP1), Sirtuinl (Sirtl), SOD2, nuclear factor erythroid 2-related factor 2 (Nrf2), and hemoxygenase-1 was upregulated, while Kelch-like ECH-associated protein 1 and histone H2AX phosphorylated on Ser-139 were downregulated by [NAD.sup.+] in [NAD.sup.+] + APAP group. Conversely, [NAD.sup.+] could not correct the elevated expression of phospho-Jun N-terminal kinase and phospho-extracellular signal-regulated kinase induced by APAP. Taken together, these findings suggest that [NAD.sup.+] confers an anti-ALI effect to enhance the expression of PARP1 and Sirt1, and to simultaneously stimulate the Nrf2 anti-oxidant signaling pathway. Keywords: acetaminophen, nicotinamide adenine dinucleotide, PARP1, Sirt1, Nrf2 Cette etude portait sur l'effet protecteur de la nicotinamide adenine dinucleotide (NAD+) contre l'insuffisance hepatique aigue (IHA) provoquee par un surdosage d'acetaminophene (APAP) chez la souris. Nous avons d'abord evalue l'effet protecteur de la NAD+ a l'aide des transaminases seriques; les resultats ont revele que la NAD+ permettait d'attenuer l'IHA engendree par l'APAP de maniere proportionnelle a la dose. Puis, nous avons procede a une coloration des tissus hepatique a l'aide d'hematoxyline-eosine et observe que la NAD+ entrainait une attenuation des anomalies histopathologiques. Nous avons aussi observe une augmentation des taux de malondialdehyde et une diminution des taux de glutathion, de superoxyde dismutase (SOD) et de glutathion peroxydase dans le groupe APAP, ce qu'il etait possible de prevenir partiellement a l'aide de l'administration prealable de NAD+. En outre, la regulation a la hausse de l'expression de la poly ADP-ribose polymerase 1 (PARP1), de la sirtuine 1 (Sirt1), de la SOD2, du Nrf2 (pour << nuclear factor erythroid 2-related factor 2 >>) et de l'hemoxygenase1, de meme que la regulation a la baisse de la proteine KEAP1 (pour << Kelch-like ECH-associated protein 1 >>) et de l'histone H2AX phosphorylee en Ser-139 qu'engendrait la NAD+ etaient plus importantes dans le groupe NAD+ + APAP qu'avec l'APAP en monotherapie. En revanche, la NAD+ ne permettait pas de corriger l'augmentation de l'expression de la phosphokinase de Jun en N-terminal et de la phosphokinase regulee par le signal extracellulaire qu'engendrait l'APAP. L'ensemble de ces resultats laissent entendre que la NAD+ confererait un effet anti IHA et permettrait de faire augmenter l'expression de la PARP1 et de la Sirt1, avec la stimulation simultanee de la voie de signalisation anti-oxydante du Nrf2. [Traduit par la Redaction] Mots-cles : acetaminophene, nicotinamide adenine dinucleotide, PARP1, Sirt1, Nrf2, 1. Introduction Acetaminophen, also called N-acetyl-p-aminophenol (APAP), is a widely used antipyretic and analgesic drug around the world (Fernandez-Checa et al. 2021). Although APAP is considered safe at therapeutic dose [...]

In this study, the hydrophobic modification of coal gasification fly ash (FA) was investigated given the adverse effects of surface hydrophilic structures on the material field. The surface of FA was modified using stearic acid (SA), which successfully altered its hydrophilic structure. When the contact angle of S-FA increased from 23.4° to 127.2°, the activation index increased from 0 to 0.98, the oil absorption decreased from 0.564 g/g to 0.510 g/g, and the BET-specific surface area decreased from 13.973 m2/g to 3.218 m2/g. The failure temperature of SA on the surface of S-FA was 210 °C. The adsorption mechanism of FA was analyzed using density functional theory (DFT) and molecular dynamics (MD). The adsorption of water molecules by FA involved both chemical and physical adsorption, with active adsorption sites for Al, Fe, and Si. The adsorbed water molecules on the surface of FA formed hydrogen bonds with a bond length of 1.5–2.5 Å, leading to agglomeration. In addition, the long alkyl chain in SA mainly relied on the central carbon atom in the (-CH3) structure to obtain electrons in different directions from the H atoms in space, increasing the Coulomb repulsion with the O atoms in the water molecule and thereby achieving the hydrophobic effect. In the temperature range of 298 K to 358 K, the combination of FA and SA became stronger as the temperature increased. [ABSTRACT FROM AUTHOR]

D-K-type bauxite from Guizhou can be used as an unburned ceramic, adsorbent, and geopolymer after low-temperature calcination. It aims to solve the problem where the color of the D–K-type bauxite changes after calcination at different temperatures. Digital image processing technology was used to extract the color characteristics of bauxite images after 10 min of calcination at various temperatures. Then, we analyzed changes in the chemical composition and micromorphology of bauxite before and after calcination and investigated the correlation between the color characteristics of images and composition changes after bauxite calcination. The test results indicated that after calcining bauxite at 500 °C to 1000 °C for 10 min, more obvious dehydration and decarburization reactions occurred. The main component gradually changed from diaspore to Al2O3, the chromaticity value of the image decreased from 0.0980 to 0.0515, the saturation value increased from 0.0161 to 0.2433, and the brightness value increased from 0.5890 to 0.7177. Studies have shown that changes in bauxite color characteristics are strongly correlated with changes in composition. This is important for directing bauxite calcination based on digital image processing from engineering viewpoints. [ABSTRACT FROM AUTHOR]

Over the past decades, emerging evidence in the literature has demonstrated that the innervation of bone is a crucial modulator for skeletal physiology and pathophysiology. The nerve‐bone axis sparked extensive preclinical and clinical investigations aimed at elucidating the contribution of nerve‐bone crosstalks to skeleton metabolism, homeostasis, and injury repair through the perspective of skeletal neurobiology. To date, peripheral nerves have been widely reported to mediate bone growth and development and fracture healing via the secretion of neurotransmitters, neuropeptides, axon guidance factors, and neurotrophins. Relevant studies have further identified several critical neural pathways that stimulate profound alterations in bone cell biology, revealing a complex interplay between the skeleton and nerve systems. In addition, inspired by nerve‐bone crosstalk, novel drug delivery systems and bioactive materials have been developed to emulate and facilitate the process of natural bone repair through neuromodulation, eventually boosting osteogenesis for ideal skeletal tissue regeneration. Overall, this work aims to review the novel research findings that contribute to deepening the current understanding of the nerve‐bone axis, bringing forth some schemas that can be translated into the clinical scenario to highlight the critical roles of neuromodulation in the skeletal system. [ABSTRACT FROM AUTHOR]

Objective: Emerging evidence suggests that glucose depletion (GD)‐induced cell death depends on system Xc−, a glutamate/cystine antiporter extensively studied in ferroptosis. However, the underlying mechanism remains debated. Our study confirmed the correlation between system Xc− and GD‐induced cell death and provided a strategic treatment for oral squamous cell carcinoma (OSCC). Methods: qPCR and Western blotting were performed to detect changes in xCT and CD98 expression after glucose withdrawal. Then, the cell viability of OSCCs under the indicated conditions was measured. To identify the GD‐responsible transcriptional factors of SLC7A11, we performed a luciferase reporter assay and a ChIP assay. Further, metabolomics was conducted to identify changes in metabolites. Finally, mitochondrial function and ATP production were evaluated using the seahorse assay, and NADP+/NADPH dynamics were measured using a NADP+/NADPH kit. Results: In OSCCs, system Xc− promoted GD‐induced cell death by increasing glutamate consumption, which promoted NADPH exhaustion and TCA blockade. Moreover, GD‐induced xCT upregulation was governed by the p‐eIF2α/ATF4 axis. Conclusions: System Xc− overexpression compromised the metabolic flexibility of OSCC under GD conditions, and thus, glucose starvation therapy is effective for killing OSCC cells. [ABSTRACT FROM AUTHOR]

Global Navigation Satellite Systems (GNSS) tropospheric tomography is a commonly used technique for the reconstruction of three-dimensional water vapour field, and a priori vertical constraint models are required for water vapour density (WVD) determination which plays a critical role in the quality of tomographic results. However, generalised exponential models were routinely used for vertical constraints and limited research was carried out in the GNSS tomography by taking epoch-by-epoch variations into consideration. In this study, an adaptive four-dimensional (4-D) WVD model for the vertical constraints in GNSS tropospheric tomography was developed based on both ERA5 and surface meteorological data in Hong Kong for each month during the period of 2015–2019, and the back-propagation neural network technique was used to develop the fitting model. Then, the WVD model was used to obtain the WVD of adjacent voxels in the vertical direction to alleviate the mis-representation of the generalised exponential model. The newly developed WVD model used in GNSS tropospheric tomography was validated using GNSS data from the Hong Kong region in the year 2020 and two tomographic epochs (00:00–00:30 UTC and 12:00–12:30 UTC) were evaluated each day. For each topographic epoch, the WVDs of the tomographic voxels including radiosonde profile are evaluated (10 voxels over 10 height layers) using radiosonde data as the reference and the WVDs of all tomographic voxels are evaluated (300 voxels over 10 height layers) using ERA5 data as the reference. Results showed that when radiosonde/ERA5 data were utilized as the references, corresponding monthly mean values of the root mean square errors (RMSEs) in the entire year reduced from 1.97/1.94 g/m3 of the traditional tomographic method to 1.56/1.36 g/m3 of the new method which showed approximately 21/30% improvements. These results suggest a better performance of the tomographic approach using the new WVD model for the vertical constraints proposed by this study by taking epoch-by-epoch information. [ABSTRACT FROM AUTHOR]

The adhesion of β -phosphogypsum product (M- β -PG) to mold is one of the factors affecting its mildew, and the possible structure and mechanism of the interaction between mold adsorbed on M- β -PG surface remain unclear. From the point of view of the interaction between the main biomolecular (Z) on the surface of mold cell wall and the main component of M- β -PG gypsum (G), the adsorption characteristics and interaction mechanism of Z on G surface were studied by means of molecular simulation and experiment. Using x-ray diffraction, gypsum phase composition analysis, x-ray fluorescence spectroscopy, scanning electron microscopy, microbial diversity detection and other tests, the object of molecular simulation modeling was determined. By analyzing the fourier infrared spectroscopy (FTIR) functional group test, the geometric optimization, the band structure and the density of states calculated by quantum mechanics; the adsorption heat, interaction energy, adsorption isotherm, adsorption bond length and mean square displacement calculated by molecular mechanics, the interaction mechanism between G and Z is studied. The results showed that the adsorption occurred primarily between the hydroxyl and carboxyl O atoms and amino N atoms of Z and Ca, S and H atoms in G. The forms of interaction were hydrogen bonding and van der Waals force interaction, which belonged to physical adsorption. On the surface of G, the most and least adsorbed were β -glucan and galactosamine, respectively, whereas the strongest and weakest adsorbed were galactomannan and galactosamine, respectively. This study provides some indication for the interaction mechanism between mold and phosphogypsum surface.