Janerin Induces Cell Cycle Arrest at the G2/M Phase and Promotes Apoptosis Involving the MAPK Pathway in THP-1, Leukemic Cell Line

Janerin is a cytotoxic sesquiterpene lactone that has been isolated and characterized from different species of the Centaurea genus. In this study, janerin was isolated form Centaurothamnus maximus, and its cytotoxic molecular mechanism was studied in THP-1 human leukemic cells. Janerin inhibited the proliferation of THP-1 cells in a dose-dependent manner. Janerin caused the cell cycle arrest at the G2/M phase by decreasing the CDK1/Cyclin-B complex. Subsequently, we found that janerin promoted THP-1 cell death through apoptosis as indicated by flow cytometry. Moreover, apoptosis induction was confirmed by the upregulation of Bax, cleaved PARP-1, and cleaved caspase 3 and the downregulation of an anti-apoptotic Bcl-2 biomarker. In addition, immunoblotting indicated a dose dependent upregulation of P38-MAPK and ERK1/2 phosphorylation during janerin treatment. In conclusion, we have demonstrated for the first time that janerin may be capable of inducing cell cycle arrest and apoptosis through the MAPK pathway, which would be one of the mechanisms underlying its anticancer activity. As a result, janerin has the potential to be used as a therapeutic agent for leukemia.     

A Projected Finite Element Update Method for Inverse Identification of Material Constitutive Parameters in transversely Isotropic Laminates

In this paper, a novel application of Finite Element Update Method (FEUM) is proposed for the inverse identification of material constitutive parameters in transversely isotropic laminates. Two-dimensional Digital Image Correlation (2D–DIC) is used for full-field measurements which is required for the identification process. Instead of measuring the in-plane displacements, which is a well-known application of 2D–DIC, we seek to measure the pseudo-displacements resulting from out-of-plane (towards camera) deflection of plate under a point load. These pseudo-displacements are basically the perspective projection of the three dimensional displacement fields on the image-plane of the image acquisition system. The cost function in this method is defined in terms of these projections instead of the true displacements – and hence the name Projected Finite Element Update Method (PFEUM). In this article, identification of in-plane elastic moduli of Carbon Fiber Reinforced Plastic (CFRP) plate has been performed using plate bending experiments which show pre-dominantly out-of-plane deflection with little contribution from the in-plane displacements. Identification results are validated by direct experimental measurements of the unknown elastic constants as well as theoretical estimates based on volume ratio of constituents. The results show good conformance between estimated and target values for at least three material parameters namely E₁, E₂ and G₁₂. Effects of experimental noise on parameter estimates has also been evaluated to explain the observed deviation in estimated parameters with current test configuration.     

Biodiversity of Secondary Metabolites Compounds Isolated from Phylum Actinobacteria and Its Therapeutic Applications

The current review aims to summarise the biodiversity and biosynthesis of novel secondary metabolites compounds, of the phylum Actinobacteria and the diverse range of secondary metabolites produced that vary depending on its ecological environments they inhabit. Actinobacteria creates a wide range of bioactive substances that can be of great value to public health and the pharmaceutical industry. The literature analysis process for this review was conducted using the VOSviewer software tool to visualise the bibliometric networks of the most relevant databases from the Scopus database in the period between 2010 and 22 March 2021. Screening and exploring the available literature relating to the extreme environments and ecosystems that Actinobacteria inhabit aims to identify new strains of this major microorganism class, producing unique novel bioactive compounds. The knowledge gained from these studies is intended to encourage scientists in the natural product discovery field to identify and characterise novel strains containing various bioactive gene clusters with potential clinical applications. It is evident that Actinobacteria adapted to survive in extreme environments represent an important source of a wide range of bioactive compounds. Actinobacteria have a large number of secondary metabolite biosynthetic gene clusters. They can synthesise thousands of subordinate metabolites with different biological actions such as anti-bacterial, anti-parasitic, anti-fungal, anti-virus, anti-cancer and growth-promoting compounds. These are highly significant economically due to their potential applications in the food, nutrition and health industries and thus support our communities’ well-being.     

Synthesis,spectroscopic investigation and biological activity of metal complexes with ONO trifunctionalalized hydrazone ligand

Mn^II, Fe^III, Co^II, Ni^II, Cu^II, Zn^II, La^III, Ru^III, Hf^IV, Zr^IV and U^VI complexes of 4-methylphenylamino acetoacetylacetone hydrazone have been synthesized and characterized by elementals analyses, i.r., u.v.–vis. spectra, magnetic moments, conductances, thermal analyses (d.t.a and t.g.a) and e.s.r measurements. The i.r. data show that, the ligand behaves as a neutral bidentate type (10), (13) and neutral tridentate type (4), (11), (12) and (21) monobasic bidentate type (7) or monobasic tridentate type (2), (3), (5), (6), (8), (14), (15), (16), (18), (19), (20) and (22) or dibasic tridentate type (5), (9) and (17) towards the metal ion. Molar conductances in DMF solution indicate that, the complexes are non-electrolytes. The e.s.r spectra of solid complexes (8) and (10) show axial type spectra with , d(x²-y²) ground state with significant covalent bond character. However, complex (12), shows an isotropic type, indicating a octahedral manganese(II) complex. Antibacterial and antifungal tests of the ligand and some of its metal complexes are also carried out and it has been observed that, the complexes are more potent bactericides and fungicides than the ligand.     

Electrical conductivity of AgI–CdI2–KI and AgI–CuI–KI ionic conducting systems

Samples of general formulae (AgI)_4?2x(CdI₂)_xKI and (AgI)_4?x(CuI)_xKI, x = 0–0.4, have been prepared and studied by conductivity measurements, powder X-ray diffraction and DSC techniques. Room temperature XRD reveals the presence of the orthorhombic K₂AgI₃ as the major component in the system. DSC traces show endothermic peaks in the temperature range of 309–330 K, depending on the sample composition. These are attributed to the solid state reaction between AgI and K₂AgI₃ to form the cubic KAg₄I₅. Impedance spectra show the prominence of electrode – electrolyte interface effect which is explained in terms of the high rate of ion migration. Ionic conductivity enhances with the increase of Cd²⁺ content, while Cu⁺ contained samples show a decrease in conductivity with increasing Cu⁺ ratio though the ionic conductivity remains higher than that of the pure one.     

Computational investigations into the operating window for memristive devices based on homogeneous ionic motion

A model that describes the homogeneous migration of oxygen vacancies as a function of electric field, temperature, and activation energy of diffusion was used to investigate the resistance switching and retention characteristics of memristive SrTiO₃ Schottky devices. Numerical simulations suggest that, though ionic motion results in switching, it is not possible to meet the criteria of fast switching and long retention simultaneously; conditions that lead to sufficiently fast switching also lead to unacceptably fast decays of programmed states. However, an operational window is found when a term accounting for local enhancement of electric field in the dielectric is included. A discussion of the appropriateness of this inclusion is provided.     

Hausdorff measure of noncompactness of certain matrix operators on the sequence spaces of generalized means

In the present paper, we derive some identities or estimates for the operator norms and the Hausdorff measures of noncompactness of certain matrix operators on the sequence spaces of generalized means. Further, by applying the Hausdorff measure of noncompactness, we obtain the necessary and sufficient conditions for such operators to be compact.     

The Nutritional and Antioxidant Potential of Artisanal and Industrial Apple Vinegars and Their Ability to Inhibit Key Enzymes Related to Type 2 Diabetes In Vitro

The main objective of the current study was to determine the physicochemical properties, antioxidant activities, and α-glucosidase and α-amylase inhibition of apple vinegar produced by artisanal and industrial methods. Apple vinegar samples were analyzed to identify their electrical conductivity, pH, titratable acidity, total dry matter, Brix, density, mineral elements, polyphenols, flavonoids, and vitamin C. The antioxidant activity of apple vinegar samples was evaluated using two tests, total antioxidant capacity (TAC) and DPPH radical scavenging activity. Finally, we determined α-glucosidase and α-amylase inhibitory activities of artisanal and industrial apple vinegar. The results showed the following values: pH (3.69–3.19); electrical conductivity (2.81–2.79 mS/cm); titratable acidity (3.6–5.4); ash (4.61–2.90); °Brix (6.37–5.2); density (1.02476–1.02012), respectively, for artisanal apple vinegar and industrial apple vinegar. Concerning mineral elements, potassium was the most predominant element followed by sodium, magnesium, and calcium. Concerning bioactive compounds (polyphenols, flavonoids, and vitamin C), the apple vinegar produced by the artisanal method was the richest sample in terms of bioactive compounds and had the highest α-glucosidase and α-amylase inhibition. The findings of this study showed that the quality and biological activities of artisanal apple vinegar were more important than industrial apple vinegar.