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Oxidative stress is an important contributor to the pathogenesis of Alzheimer’s disease (AD). The overproduction of reactive oxygen species observed in AD patients results in the loss of mitochondrial function, altered metal ion homeostasis, lipopolysaccharide metabolism disorder, reduced anti-oxidant defense, increased release of inflammatory factors, and the aggravation and accumulation of amyloid-beta and tau hyper-phosphorylation, which directly cause synaptic and neuronal loss and lead to cognitive dysfunction. Thus, oxidative stress proves to be a fundamental part of AD development and progression, suggesting the potential benefits of anti-oxidant-based therapies for AD. In this study, we found that a water-soluble extract of Artemisia annua (WSEAA), a traditional Chinese herbal medicine, has a strong anti-oxidant function. We also found that WSEAA is able to improve the cognitive function of 3xTg AD mice. However, the mechanisms and molecular targets underlying WSEAA action are still not known. In order to uncover the potential molecular mechanisms involved, we used a combination of network pharmacology and different experimental approaches. Obtained results revealed key genes (such as AKT1, BCL2, IL-6, TNF-[Formula: see text] and BAX) and signaling pathways (like PI3K-AKT and BCL2/BAX) are closely associated with the biological processes responding to oxidative stress. Further verification of the survival/anti-oxidant effects of WSEAA in vitro and in vivo showed that the extract has anti-oxidatant/neuronal survival action against H2O2-induced damage, and is thus able to prevent the cognitive decline and pathological changes of 3xTg transgenic (3xTg) mice via the regulation of key target-genes and pathways, such as PI3K-AKT and BCL2/BAX, related to survival/apoptosis. Our findings strongly indicate the potential of WSEAA for the prevention and treatment of AD.

This paper is concerned with the existence, nonexistence, uniqueness, and non-uniqueness of solutions for a singular parabolic equation in one dimension case. For different cases of some constant m of the equation, we study the uniqueness of solutions for m > − 1, the nonexistence of solutions for m ≤ − p, and the existence and non-uniqueness of solutions for − p

In this stady, a graphene-chitosan (GR-CS) modified glassy carbon electrode (GCE) was prepared by in situ reduction. The obtained electrode was characterized by FT-IR spectroscopy and Raman spectroscopy, and the results showed that the graphene oxide (GO) was deoxygenized successfully. On this basis, the electrochemical behavior of 4-nonylphenol (4-NP) was studied by using cyclic voltammetry and differential pulse voltammetry. It was found that the oxidation current on GR-CS/GCE electrode was significantly larger than on the GCE and GO-CS/GCE electrodes. The oxidation potential shifted negatively, indicating that the GR-CS/GCE electrode had obviously catalytic activity on the 4-NP's oxidation. Experimental parameters, such as the accumulation potential and time, scan rate, and pH value of buffer solution were optimized. Under the optimized conditions, the oxidation peak current was proportional to 4-NP concentration in the range between 0.01–40.0 μM, the linear equation was I (μA) = 0.364 C (μM) + 0.618 ( R = 0.9988), and the detection limit was 0.0052 μM ( S/N = 3). Finally, this proposed sensor was successfully employed to determine 4-NP in real samples with the recoveries ranging in 95.0%–101.0%.

This paper is devoted to the existence and regularity of the homogenous Dirichlet boundary value problem for a singular nonlinear elliptic equation with natural growth in the gradient. By certain transformations, the problem can be transformed formally into either a Dirichlet problem or boundary blowup problems without gradient term, for which the corresponding existence results are also derived, which is a partial extension and supplement to the previous works. Copyright © 2008 John Wiley & Sons, Ltd.

In this paper, we are concerned with the existence of positive solutions for a singular p-Laplacian differential equation $$ (\varphi _p (u'))' + \frac{\beta } {r}\varphi _p (u') - \gamma \frac{{|u'|^p }} {u} + g(r) = 0,0 < r < 1, $$ subject to the Dirichlet boundary conditions: u(0) = u(1) = 0, where ϕ p (s) = |s| p−2 s,p > 2, β > 0, γ > $$ \tfrac{{p - 1}} {p} $$ (β + 1), and g(r) ∈ C 1[0, 1] with g(r) > 0 for all r ∈ [0, 1]. We use the method of elliptic regularization, by carrying out two limit processes, to get a positive solution.