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Background: Arbuscular mycorrhiza (AM) refers to a symbiotic association between plant roots and fungi that enhances the uptake of mineral nutrients from the soil and enables the plant to tolerate abiotic and biotic stresses. Although previously reported RNA-seq analyses have identified large numbers of AM-responsive genes in model plants, such as Solanum lycopersicum L., further studies are underway to comprehensively understand the complex interactions between plant roots and AM, especially in terms of the short- and long-term responses after inoculation. Results: Herein, we used RNA-seq technology to obtain the transcriptomes of tomato roots inoculated with the fungus Rhizophagus irregularis at 7 and 30 days post inoculation (dpi). Of the 1,019 differentially expressed genes (DEGs) in tomato roots, 635 genes showed differential expressions between mycorrhizal and non-mycorrhizal associations at the two time points. The number of upregulated DEGs far exceeded the number of downregulated ones at 7 dpi, and this difference decreased at 30 dpi. Several notable genes were particularly involved in the plant defense, plant growth and development, ion transport, and biological processes, namely, GABAT, AGP, POD, NQO1, MT4, MTA, and AROGP3. In addition, the Kyoto encyclopedia of genes and genomes pathway enrichment analysis revealed that some of the genes were involved in different pathways, including those of ascorbic acid (AFRR, GME1, and APX), metabolism (CYP, GAPC2, and CAM2), and sterols (CYC1 and HMGR), as well as genes related to cell division and cell cycle (CDKB2 and PCNA). Conclusion: These findings provide valuable new data on AM-responsive genes in tomato roots at both short- and long-term postinoculation stages, enabling the deciphering of biological interactions between tomato roots and symbiotic fungi. [ABSTRACT FROM AUTHOR]

The effect of Ti content in various concentrations as an alloying element with Al on both microhardness and crystallization structure of aluminum–titanium alloys was studied, utilizing x-ray diffraction (XRD) and a scanning electron microscope (SEM). To study the electrochemical and corrosion performance of Al and its investigated alloys in 0.5 M solutions of HCl and H3PO4, two different techniques were used: extrapolation of Tafel plot and electrochemical impedance spectroscopy (EIS). Tafel plots and EIS revealed a similar trend. Generally, the rate of corrosion of the alloys was higher than that of Al. This investigation exhibited that the corrosion of Al alloying with Ti increased with an increase in both Ti content and temperature, which is due to reducing the growth of oxide film on the surface. Changes in the standard values of both entropy (ΔS) and enthalpy (ΔH), in addition to apparent activation energy (Ea) of corrosion processes of Al and its alloys in HCl and H3PO4, were evaluated. The evaluated data indicated negative values of ΔS, while the values of ΔH were positive. Besides, the decrease in ΔH value with the increase of Ti content in the alloy revealed that the dissolution of the studied alloys was fast. The positive values of ΔH were accompanied by an endothermic process. On the other hand, the activation energy (Ea) was decreased as a result of Al alloying with Ti in the two mentioned acids. Those results were supported by the corrosion current density (icorr.) and impedance parameters. By comparing the data obtained for both HCl and H3PO4 in all investigated electrodes, the corrosion current density (icorr.) in H3PO4 was lower than that in HCl. Such behavior can be ascribed to the aggressive attack of Cl¯ ions on the surfaces of the investigated electrodes, leading to pits formation. [ABSTRACT FROM AUTHOR]

While chronic smoking triggers cardiovascular disease, controversy remains regarding its effects on the brain and cognition. We investigated the effects of long-term cigarette smoke (CS) exposure (CSE) on cerebrovascular function, neuronal injury, and cognition in a novel mouse exposure model. Longitudinal studies were performed in CS or air-exposed mice, 2 hours/day, for up to 60 weeks. Hypertension and carotid vascular endothelial dysfunction (VED) occurred by 16 weeks of CSE, followed by reduced carotid artery blood flow, with oxidative stress detected in the carotid artery, and subsequently in the brain of CS-exposed mice with generation of reactive oxygen species (ROS) and secondary protein and DNA oxidation, microglial activation and astrocytosis. Brain small vessels exhibited decreased levels of endothelial NO synthase (eNOS), enlarged perivascular spaces with blood brain barrier (BBB) leak and decreased levels of tight-junction proteins. In the brain, amyloid-β deposition and phosphorylated-tau were detected with increases out to 60 weeks, at which time mice exhibited impaired spatial learning and memory. Thus, long-term CSE initiates a cascade of ROS generation and oxidative damage, eNOS dysfunction with cerebral hypoperfusion, as well as cerebrovascular and BBB damage with intracerebral inflammation, and neuronal degeneration, followed by the onset of impaired cognition and memory. [ABSTRACT FROM AUTHOR]