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This study investigates the pyrolysis and adsorption properties of biochar derived from coconut shell (BC-CS), rice husk (BC-RH), and cow manure (BC-CM) under varying thermal treatment conditions. Biochar samples were produced at 800 °C with residence times ranging from 0 to 60 min. Their characteristics were analyzed using their Brunauer–Emmett–Teller (BET) surface area, total pore volume, and pore diameter measurements. BC-CM exhibited the highest BET surface area of 263.3 m2/g and a total pore volume of 0.164 cm3/g, while BC-RH and BC-CS showed maximum BET surface areas of 220.62 m2/g and 197.38 m2/g, respectively. Nitrogen adsorption–desorption isotherms revealed distinct microporous and mesoporous structures, with BC-CM demonstrating superior adsorption capacity across all relative pressures. The adsorption kinetics of methylene blue (MB) were examined at initial concentrations of 1 ppm, 5 ppm, and 10 ppm, with varying biochar doses (0.1 g, 0.3 g, and 0.5 g). The results showed that the adsorption rate constant (k) decreased with higher initial MB concentrations, while the equilibrium adsorption capacity (qe) increased. BC-CM achieved the highest qe of 2.18 mg/g at 10 ppm and a 0.5 g dose, followed by BC-RH-800-45 (1.145 mg/g) and BC-CS (0.340 mg/g). The adsorption process was well described by a pseudo-second-order kinetic model, indicating chemisorption as the dominant mechanism. Increasing biochar doses improved MB removal efficiency, highlighting the dose-dependent nature of adsorption. These findings underscore the importance of optimizing pyrolysis parameters to enhance biochar's adsorption performance and identify key factors influencing its effectiveness in environmental applications. [ABSTRACT FROM AUTHOR]

Activation of the phosphatidylinositol 3-kinase (PI3K) signaling pathway is a pervasive event in tumorigenesis due to PI3K mutation and dysfunction of phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Pharmacological inhibition of PI3K has resulted in variable clinical outcomes, however, raising questions regarding the possible mechanisms of unresponsiveness and resistance to treatment. WWP1 is an oncogenic HECT-type ubiquitin E3 ligase frequently amplified and mutated in multiple cancers, as well as in the germ lines of patients predisposed to cancer, and was recently found to activate PI3K signaling through PTEN inactivation. Here, we demonstrate that PTEN dissociated from the plasma membrane upon treatment with PI3K inhibitors through WWP1 activation, whereas WWP1 genetic or pharmacological inhibition restored PTEN membrane localization, synergizing with PI3K inhibitors to suppress tumor growth both in vitro and in vivo. Furthermore, we demonstrate that WWP1 inhibition attenuated hyperglycemia and the consequent insulin feedback, which is a major tumor-promoting side effect of PI3K inhibitors. Mechanistically, we found that AMPKa2 was ubiquitinated and, in turn, inhibited in its activatory phosphorylation by WWP1, whereas WWP1 inhibition facilitated AMPK[alpha]2 activity in the muscle to compensate for the reduction in glucose uptake observed upon PI3K inhibition. Thus, our identification of the cell-autonomous and systemic roles of WWP1 inhibition expands the therapeutic potential of PI3K inhibitors and reveals new avenues of combination cancer therapy., Introduction Phosphatidylinositol 3-kinases (PI3Ks) play a critical role in regulating various biological functions, including cell growth, survival, differentiation, metabolism, and motility. Dysregulation of the PI3K signaling pathway is one of [...]

Abstract Tumor suppressors are frequently downregulated in human cancers and understanding of the mechanisms through which tumor cells restrict the expression of tumor suppressors is important for the prognosis and intervention of diseases. The promyelocytic leukemia (PML) protein plays a critical role in multiple tumor suppressive functions, such as growth inhibition, apoptosis, replicative senescence, suppression of oncogenic transformation, and inhibition of migration and angiogenesis. These tumor suppression functions are recapitulated in several mouse models. The expression of PML protein is frequently downregulated in diverse types of human tumors and this downregulation often correlates with tumor progression. Recent evidence has emerged that PML is aberrantly degraded in various types of tumors through ubiquitination-dependent mechanisms. Here, we summarize our current understanding of the PML ubiquitination/degradation pathways in human cancers. We point out that multiple pathways lead to PML ubiquitination and degradation. Furthermore, the PML ubiquitination processes are often dependent on other types of posttranslational modifications, such as phosphorylation, prolylisomerization, and sumoylation. Such feature indicates a highly regulated nature of PML ubiquitination in different cellular conditions and cell contexts, thus providing many avenues of opportunity to intervene PML ubiquitination pathways. We discuss the potential of targeting PML ubiquitination pathways for anti-cancer therapeutic strategies.