Neuroprotection of Truncated Peptide IIAVE from Isochrysis zhanjiangensis: Quantum Chemical, Molecular Docking, and Bioactivity Studies.

Parkinson's disease (PD) is a progressive neurodegenerative disorder of the elderly for which there is no cure or disease-modifying therapy. Mitochondrial dysfunction and oxidative stress play a central role in dopaminergic neurodegeneration in PD. Therefore, antioxidants are considered a promising neuroprotective approach. In in vivo activity studies, 6-OHDA-induced oxidative stress in SH-SY5Y cells was established as a model of PD for cellular experiments. IIAVE (Ile-Ile-Ala-Val-Glu) was derived from Isochrysis zhanjiangensis octapeptide (IIAVEAGC), which has a small molecular weight. The structure and antioxidant activity of IIAVE were tested in a previous study and proved to have good antioxidant potential. In this study, the chemical properties of IIAVE were calculated using quantum chemical methods, including frontier molecular orbital (FMO), molecular electrostatic potential (MEP), natural population analysis (NPA), and global reactivity properties. The interaction of IIAVE with Bcl-2 and DJ-1 was investigated using the molecular docking method. The results showed that IIAVE promoted the activation of the Keap1/Nrf2 pathway and up-regulated the expression of the superoxide dismutase 1 (SOD-1) protein by inhibiting the level of reactive oxygen species (ROS) in cells. In addition, IIAVE inhibits ROS production and prevents 6-OHDA-induced oxidative damage by restoring mitochondrial membrane potential. Furthermore, IIAVE inhibited cell apoptosis by increasing the Bcl-2/Bax ratio and inhibiting the activation of Caspase-9 and Caspase-3. Thus, IIAVE may become a potential drug for the treatment and prevention of PD.

Understanding the Impacts of Different Impurities on Elemental Mercury Removal by CaS in Chemical Looping Combustion of Coal: A First Principle Study.

CaSO4 has the advantages of abundant yield, high oxygen-carrying capacity, low cost, and no heavy metal pollution, making it promising as an oxygen carrier for chemical looping combustion (CLC). In comparison with other oxygen carriers, CaS as the reduced product of CaSO4 exhibits superior adsorption efficiency for Hg0 in the flue gas. In this paper, density functional theory (DFT) was used to investigate the adsorption mechanism of Hg0 on the adsorbent surface of CaS(001). The adsorption energies of different oxidized mercury species such as HgS, HgCl, and HgBr over the CaS surface were summarized. Furthermore, the effects of various flue gas components including SO2, H2S, S, HCl, Cl2, CO, H2, H2O, and C on Hg0 adsorption over the CaS(001) surface were evaluated. The results show that Hg0 can be adsorbed on the CaS(001) surface in a chemisorption manner with a reaction energy of -65.1 kJ/mol. The adsorption energy of different forms of mercury on the CaS(001) surface varies greatly, and mercury in the oxidized state is more easily captured by CaS. SO2 inhibits while other flue gas components promote Hg0 adsorption over the CaS surface. Overall, CaS tends to adsorb mercury in the reduction reactor and release mercury when CaS is re-oxidized to CaSO4 in the oxidation reactor. This is detrimental to mercury removal in the CLC of coal. This study sheds light on the migration and transformation of mercury in the CLC of coal with CaSO4 as the oxygen carrier.

Oxygen-Induced Elemental Mercury Oxidation in Chemical Looping Combustion of Coal.

Mercury emission is an important issue during chemical looping combustion (CLC) of coal. The aim of this work is to explore the effects of different flue gas components (e.g., HCl, NO, SO2, and CO2) on mercury transformation in the flue gas cooling process. A two-stage simulation method is used to reveal the reaction mechanism of these gases affecting elemental mercury (Hg0) oxidation. Furthermore, using this method, Hg0 oxidation by eight oxygen carriers (Co3O4, CaSO4, CeO2, Fe2O3, Al2O3, Mn2O3, SiO2, and CuO) commonly used in CLC are investigated and their Hg0 oxidation efficiencies were compared with the existing experimental results. The results show that HCl, NO, and CO2 promote Hg0 oxidation during flue gas cooling, while SO2 inhibits Hg0 oxidation. The stronger the oxygen release capacity of oxygen carriers, the higher the oxidation efficiency of Hg0 becomes. The order of Hg0 removal efficiency from high to low is Co3O4, CuO, Mn2O3, CaSO4, Fe2O3, CeO2, Al2O3, and SiO2, and this sequence is in good agreement with the existing experimental results. Different flue gas components directly or indirectly affect the O2 content, thus affecting the content of gaseous oxidized mercury (Hg2+). Different oxygen carriers have different oxygen release capacities and different Hg0 oxidation efficiencies. Therefore, O2 is the core species affecting the mercury transformation in CLC.

Predicting hepatocellular carcinoma through cross-talk genes identified by risk pathways.

Hepatocellular carcinoma (HCC) is the most frequent type of liver cancer with poor survival rate and high mortality. Despite efforts on the mechanism of HCC, new molecular markers are needed for exact diagnosis, evaluation and treatment. Here, we combined transcriptome of HCC with networks and pathways to identify reliable molecular markers. Through integrating 249 differentially expressed genes with syncretic protein interaction networks, we constructed a HCC-specific network, from which we further extracted 480 pivotal genes. Based on the cross-talk between the enriched pathways of the pivotal genes, we finally identified a HCC signature of 45 genes, which could accurately distinguish HCC patients with normal individuals and reveal the prognosis of HCC patients. Among these 45 genes, 15 showed dysregulated expression patterns and a part have been reported to be associated with HCC and/or other cancers. These findings suggested that our identified 45 gene signature could be potential and valuable molecular markers for diagnosis and evaluation of HCC.

Designing of dual inhibitors for GSK-3ß and CDK5: Virtual screening and in vitro biological activities study.

Alzheimer's disease is a multifactorial neurodegenerative disorder with many drug targets contributing to its etiology. Despite the devastating effects of this disease, therapeutic methods for treating Alzheimer's disease remain limited. The multifactorial nature of Alzheimer's disease strongly supports a multi-target rationale as a drug design strategy. Glycogen synthase kinase-3 beta and cyclin-dependent kinase 5 have been identified as being involved in the pathological hyperphosphorylation of tau proteins, which leads to the formation of neurofibrillary tangles and causes Alzheimer's disease. In this study, using a molecular docking method to screen a virtual library, we discovered molecules that can simultaneously inhibit Glycogen synthase kinase-3 beta and cyclin-dependent kinase 5 as lead compounds for the treatment of Alzheimer's disease. The docking results revealed the key residues in the substrate binding sites of both Glycogen synthase kinase-3 beta and cyclin-dependent kinase 5. A receiver operating characteristic curve indicated that the docking model consistently and selectively scored the majority of active compounds above decoys. The pre-treatment of cells with screened compounds protected them against Aß25-35- induced cell death by up to 80%. Collectively, these findings suggest that some compounds have potential to be promising multifunctional agents for Alzheimer's disease treatment.

Identification of breast cancer recurrence risk factors based on functional pathways in tumor and normal tissues.

The recurrence of breast cancer (BC) is a serious therapeutic problem, and the risk factors for recurrence urgently need to be identified. In this study, we examined the functional pathways in tumor and normal tissues to more comprehensively identify biomarkers for the risk of BC recurrence. We collected tumor and normal tissue gene expression profiles of recurrent BC patients and non-recurrent BC patients from the TCGA database.We derived an expression interval (mean ± 1.96SD) based on non-recurrent patients rather than a single value, such as a mean or median. If the expression of a gene was significantly different from its normal expression interval, it was considered a differentially expressed gene. Eight pathways that significantly distinguished recurrent and non-recurrent BC patients were obtained based on 65% accuracy, and these pathways were all associated with the immune response and sensitivity to drugs. The genes in these eight pathways were also used to analyze survival, and the significance level reached 0.003 in an independent dataset (p = 0.02 in tumor and p = 0.03 in normal tissue). Our results reveal that the integration of tumor and normal tissue functional analyses can comprehensively enhance the understanding of BC prognosis.

Amorphous vanadium oxide matrixes supporting hierarchical porous Fe3O4/graphene nanowires as a high-rate lithium storage anode.

Developing electrode materials with both high energy and power densities holds the key for satisfying the urgent demand of energy storage worldwide. In order to realize the fast and efficient transport of ions/electrons and the stable structure during the charge/discharge process, hierarchical porous Fe3O4/graphene nanowires supported by amorphous vanadium oxide matrixes have been rationally synthesized through a facile phase separation process. The porous structure is directly in situ constructed from the FeVO4·1.1H2O@graphene nanowires along with the crystallization of Fe3O4 and the amorphization of vanadium oxide without using any hard templates. The hierarchical porous Fe3O4/VOx/graphene nanowires exhibit a high Coulombic efficiency and outstanding reversible specific capacity (1146 mAh g(-1)). Even at the high current density of 5 A g(-1), the porous nanowires maintain a reversible capacity of ∼500 mAh g(-1). Moreover, the amorphization and conversion reactions between Fe and Fe3O4 of the hierarchical porous Fe3O4/VOx/graphene nanowires were also investigated by in situ X-ray diffraction and X-ray photoelectron spectroscopy. Our work demonstrates that the amorphous vanadium oxides matrixes supporting hierarchical porous Fe3O4/graphene nanowires are one of the most attractive anodes in energy storage applications.