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Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by oxidative stress that triggers motor neurons loss in the brain and spinal cord. However, the mechanisms underlying the exact role of oxidative stress in ALS-associated neural degeneration are not definitively established. Oxidative stress-generated phospholipid peroxides are known to have extensive physiological and pathological consequences to tissues. Here, we discovered that the deficiency of glutathione peroxidase 4 (GPX4), an essential antioxidant peroxidase, led to the accumulation of phospholipid peroxides and resulted in a loss of motor neurons in spinal cords of ALS mice. Mutant human SOD1

The mitochondrial complexes are prone to sirtuin (Sirt)3-mediated deacetylation modification, which may determine cellular response to stimuli, such as oxidative stress. In this study, we show that the cytochrome c oxidase (COX)-1, a core catalytic subunit of mitochondrial complex IV, was acetylated and deactivated both in 2,2'-azobis(2-amidinopropane) dihydrochloride-treated NIH/3T3 cells and hydrogen peroxide-treated primary neuronal cells, correlating with apoptotic cell death induction by oxidative stress. Inhibition of Sirt3 by small interfering RNA or the inhibitor nicotinamide induced accumulation of acetylation of COX-1, reduced mitochondrial membrane potential, and increased cell apoptosis. In contrast, overexpression of Sirt3 enhanced deacetylation of COX-1 and inhibited oxidative stress-induced apoptotic cell death. Significantly, rats treated with ischemia/reperfusion injury, a typical oxidative stress-related disease, presented an inhibition of Sirt3-induced hyperacetylation of COX-1 in the brain tissues. Furthermore, K13, K264, K319, and K481 were identified as the acetylation sits of COX-1 in response to oxidative stress. In conclusion, COX-1 was discovered as a new deacetylation target of Sirt3, indicating that the Sirt3/COX-1 axis is a promising therapy target of stress-related diseases.-Tu, L.-F., Cao, L.-F., Zhang, Y.-H., Guo, Y.-L., Zhou, Y.-F., Lu, W.-Q., Zhang, T.-Z., Zhang, T., Zhang, G.-X., Kurihara, H., Li, Y.-F., He, R.-R. Sirt3-dependent deacetylation of COX-1 counteracts oxidative stress-induced cell apoptosis.

Temozolomide (TMZ) is generally applied for glioma treatment, while drug resistance of TMZ limits its therapeutic efficacy. Mannose exerts evident anti-tumor effect. We intended to investigate whether mannose enhanced TMZ sensitivity to glioma and examined the underlying mechanism.MTT and clone formation assays were performed to detect cell viability and proliferation. Cell apoptosis was measured by flow cytometry. The protein and gene expression levels were detected by Western blot and qRT-PCR assays. Xenograft glioma model was established to explore the influence of mannose in vivo.Mannose inhibited glioma cell growth, which was facilitated by knockdown of phosphomannose isomerase (PMI) while reversed by overexpression of PMI. Mannose enhanced the sensitivity of glioma cells to TMZ, indicated by the further inhibited cell viability and colony formation and the aggravated cell apoptosis, which was reversed by overexpression of O6-methylguanine DNA methyltransferase (MGMT). Furthermore, mannose and TMZ inhibited MGMT expression and Wnt/β-catenin activation. Moreover, activating Wnt/β-catenin pathway blocked anti-proliferative effect induced by mannose and TMZ, which was further suppressed by overexpressed MGMT. Mannose inhibited glioma growth, suppressed Ki67 and downregulated MGMT and β-catenin in vivo.Mannose inhibited MGMT to enhance sensitivity of glioma cells to TMZ, with Wnt/β-catenin pathway involvement. Our data suggested that mannose could be an innovative agent to improve glioma treatment, particularly in TMZ-resistant glioma with high MGMT.

A process-oriented methodology to conduct precise evaluation temporally and spatially on temperature suitability for potato growth was applied in China. Arable lands in China were gridded with 1 km×1 km geographic units, and potential potato phenology in each unit was automatically identified in terms of the potato planting initial temperature and effective accumulated temperature. A temperature thermal response coefficient model was used to compute a temperature suitability value for each day of potato phenology in each geographic unit. In addition, five temperature suitability ranking methods were applied to define suitable areas: (1) upper fourth quantile, (2) median, (3) expected value+1/4 standard deviation, (4) expected value+1/2 standard deviation, (5) expected value+1 standard deviation. A validation indicator was innovated to test the effectiveness of the five ranking methods. The results showed that from a strict degree point of view, the five methods sequence was as follows: 1=3>4>2>5, with a and c determined as the two best ranking methods. For methods 1 and 3, the suitable potato growing area was 1 of 57.76×104 km2. In addition, the suitable areas were spatially coincident with the main potato producing counties. The study output technically supports the proposal from China's government that there is a large potential area to grow winter-ploughed potato in South China because the potential suitable area for growing potato is approximately 2×107 ha. In southeast Heilongjiang and east Jilin, where it is hilly and mountainous, there are still some potentially suitable areas for potato growing accounting for nearly 2.32×106 ha. The authors suggest to optimize the agricultural regionalization and layout in China and to adjust the cropping pattern structure.

This paper proposes a new approach is referred to as condensed nearest neighbor decision rule (CNN) input weight sequential feed-forward neural networks (CIW-SFFNS). In this paper, it is firstly shown that the difference of optimization constraints between the extreme learning machine (ELM) and constrained-optimization-based extreme learning machine. For the second time, this paper proposes a method that using CNN to select the hidden-layer weights from example. Moreover, we compare error minimized extreme learning machines (EM-ELM), support vector sequential feed-forward neural networks (SV-SFFNS) and CIW-SFFNS from two aspects:test accuracy and the number of hidden nodes. We present the result of an experimental study on 10 classification sets. The CIW-SFFNS algorithm has a statistically significant improvement in generalization performance than EM-ELM and SV-SFFNS.

Core Vector Machine (CVM) can be used to deal with large data sets by find minimum enclosing ball (MEB), but one drawback is that CVM is very sensitive to the outliers. To tackle this problem, we propose a novel Position Regularized Core Vector Machine (PCVM).In the proposed PCVM, the data points are regularized by assigning a position-based weighting. Experimental results on several benchmark data sets show that the performance of PCVM is much better than CVM.

Low permeability, low abundance, water-bearing gas reservoirs are widely distributed in China, and their reserves constitute 85% of all kinds of reservoirs in current. It has important realistic meanings to develop them. Determining of reasonable gas well production is the prerequisite to achieving long-term high productivity and stable production. This paper takes Shanggu gas field at Sulige Gas Field for example, respectively from the dynamic data analogy methods, the pressure drop rate statistical methods, gas curve methods, production system nodal analysis methods, and studied the reasonable capacity of the low permeability gas reservoir. Through comprehensive analysis，the comprehensive technical indexes about single well reasonable production was determined.

Natural fractures controlled by the palaeotectonic stress field and artificial fractures controlled by the current stress field totally determined the distribution of the seepage system in super low permeability reservoir. Synthetically evaluation of the influence of fractures on oilfield development and the research on regularity of natural fractures distribution and the effect of stress field on the fractures are made in this paper, which is of important theoretical and practical significance in improving the development effect in super low permeability reservoir.

Through laboratory experiments, a green cross-linked movable gel has been developed, which has been used for reservoir profile modification. The main agent of gel is hydrophobic associating polymer, concentration is 3000mg/L; the cross-linking agent is Aluminum citrate from complex of Aluminum ion and citric acid root ion. The best molar ratio of aluminum ions and citrate ions is 1.5:1 in complex reaction, the amount is 140mg/L; the retarder is tartaric acid sodium, the amount is 150mg/L; The stabilizer is thiourea, the amount is 800mg/L; The strength of the green cross-linked movable gel is 3.12×104mPa.s, gelling time 36h, Stable time 160d; It is suitable for low-temperature reservoir profile modification, and salt resistance is good. Laboratory experiments show that the green cross-linked movable gel have strong plugging capacity and improving profile ability. The green cross-linked movable gel has strong three dimensional network structure, which be observed through the environmental scanning electron microscopy.

The new polypyridyl ligand MIP {MIP = 2-(2,3-methylenedioxyphenyl)imidazo[4,5- f ]1,10-phenanthroline} and its ruthenium(II) complexes [Ru(phen) 2 (MIP)] 2+ ( 1 ) (phen = 1,10-phenanthroline) and [Ru(dmp) 2 (MIP)] 2+ ( 2 ) (dmp = 2,9-dimethyl-1,10-phenanthroline) were synthesized and characterized by elemental analysis, MS and 1 H NMR spectroscopy. The DNA-binding properties of the two complexes to calf-thymus DNA (CT-DNA) were investigated by different spectrophotometric methods and viscosity measurements, as well as equilibrium dialysis and circular dichroism spectroscopy. The results suggest that complex 1 binds to CT-DNA through intercalation, and complex 2 binds to CT-DNA via a partial intercalative mode. This difference in binding mode probably is caused by the different ancillary ligands. Also, when irradiated at 400 nm, complex 1 was found to be a more-effective DNA-cleaving agent than complex 2 .

A novel polypyridyl ligand 2-(4′-benzyloxyphenyl)imidazo[4,5-f][1,10]phenanthroline (BPIP) and its complex [Ru(bpy)2(BPIP)]2+ (1) (bpy = 2,2′-bipyridine) and (2) [Ru(phen)2(BPIP)]2+ (phen = 1,10-phenanthroline) have been synthesized and characterized by elemental analysis, electrospray mass spectra and 1H NMR. The DNA-binding properties of the two complexes were investigated by spectroscopic and viscosity measurements. The results suggest that both complexes bind to DNA via an intercalative mode. Both complexes can enantioselectively interact with calf thymus DNA (CT-DNA) in a way. The Λ enantiomer of complex 1 is slightly predominant for binding to CT-DNA to the Δ enantiomer. Under irradiation at 365 nm, both complexes have also been found to promote the photocleavage of plasmid pBR 322 DNA. Inhibitors studies suggest that singlet oxygen (1O2) and hydroxyl radical ( OH) play a significant role in the cleavage mechanism for both complexes. Moreover, the DNA-binding and photocleavage properties of both complexes were compared with that of [Ru(bpy)2(BPIP)]2+ and [Ru(phen)2(BPIP)]2+. The experimental results indicate that methene group existence or not have a significant effect on the DNA-binding and cleavage mechanism of these complexes.