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Background & Objective: Deregulation of autophagy is involved in the development and progression of Parkinson's disease. ATG7, an E1 like enzyme, plays a key role in autophagy. This study aimed to investigating the association between ATG7 polymorphisms and PD susceptibility. Methods: Single nucleotide polymorphisms of ATG7, including rs7625184 and rs2606750, were identified by polymerase chain reaction-restriction fragment length polymorphism in a Han Chinese population consisting of 312 PD patients and 309 healthy controls. Results: Genotyping analyses showed that none of the 2 SNPs was significantly associated with PD risk. Conclusions: Our results suggest that rs7625184 and rs2606750 are not associated with PD susceptibility. Further studies are warranted to reveal the links between ATG7 and PD. [ABSTRACT FROM AUTHOR]

Modern hexaploid wheat has several diploid and tetraploid predecessors. Morpho-physiological adaptation and the adaptation to drought of these different ploidy wheat species is largely unknown. To investigate the adaptation to drought stress, eight accesssions (two wild diploid (2n) accessions of Aegilops tauschii Coss., two domesticated diploid (2n) accessions of Triticum monococcum L., two domesticated tetraploid (4n) accessions of Triticum dicoccum Schrank ex Schübl. and two domesticated hexaploid (6n) accessions of Triticum aestivum L.) were exposed to three water regimes: (i) well-watered control (WW, 80% field capacity (FC)), (ii) moderate water stress (MS, 50% FC), and (iii) severe water stress (SS, 25% FC) from 30 days after sowing to maturity. The results showed that accession (A), water regime (W), and the interaction of A×W significantly affected yield, morpho-physiological traits, biochemical characteristics and biomass allocation. In theWWtreatment, the aboveground biomass, ear biomass, grain yield and harvest index increased, whereas the number of spikes and spikelets per plant decreased from accessions of T. monococcum to T. dicoccum to T. aestivum. Across all accessions, yields decreased by 29% under moderate water stress and 61% under severe water stress. In all three water regimes, yields were positively correlated with photosynthesis (Pn) per plant (Pn × leaf area) at jointing and anthesis, largely the result of the differences and changes in leaf area. Water use efficiency for grain (WUEG) decreased by 2-6% in T. monococcum, but it increased by 15-16% in T. dicoccum and T. aestivum under drought stress. Analysis of the allometric relationships between aboveground biomass (MAB) and root biomass (Mroot) in the different species indicated that less biomass was allocated to roots with greater polyploidy while more biomass was allocated to roots with drought in A. tauschii, but not in the domesticated species. We conclude that domestication, selection and breeding of higher ploidy wheat has increased wheat yields primarily by increasing aboveground biomass and harvest index, increases that were maintained under water stress. [ABSTRACT FROM AUTHOR]

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive type of blood malignancy, deriving from T-cell progenitors in the thymus, and comprises 10-15% of pediatric and 25% of adult primary ALL cases. Despite advances, 20% of pediatric and the majority of adult patients with T-ALL succumb to mortality from resistant or relapsed disease, and the survival rate for patients with resistant or relapsed T-ALL remains poor. Alterations in the expression of Forkhead box protein M1 (FoxM1) have been detected in several types of cancer, and the inhibition of FoxM1 has been investigated as therapeutic strategy in cancer. The present study investigated the effects of the inhibition of FoxM1 by thiostrepton in human T-ALL Jurkat cells. The cells were treated with different concentrations of thiostrepton, either alone or in combination with doxorubicin. Cell viability was measured using CCK-8 assays and the cell cycle distribution, apoptosis and cell-associated mean fluorescence intensity of intracellular doxorubicin were assessed using flow cytometric analysis. The mRNA and protein expression levels were detected by reverse transcription-quantitative polymerase chain reaction and western blot analyses. The inhibition of FoxM1 by thiostrepton significantly decreased the proliferation of the Jurkat cells proliferation in a time- and dose-dependent manner. Cell arrest at the G2/M phase, and apoptosis was significantly increased in the thiostrepton-treated Jurkat cells. Thiostrepton reduced the half maximal inhibitory concentration of doxorubicin in the Jurkat cells, and significantly enhanced the cytotoxicity of doxorubicin within the Jurkat cells by enhancing doxorubicin-induced apoptosis and increasing the accumulation of intracellular doxorubicin. Furthermore, the inhibition of FoxM1 by thiostrepton enhanced doxorubicin-induced apoptosis, possibly through a caspase-3-dependent pathway, and increased the accumuation of intracellular doxorubicin, possibly through downregulating the expression of glutathione S-transferase pi. Collectively, the results of the present study suggested that targeting FoxM1 with thiostrepton resulted in potent antileukemia activity and chemosensitizing effects in human T-ALL Jurkat cells. [ABSTRACT FROM AUTHOR]

The oblique propagation of ion-acoustic soliton-cnoidal waves in a magnetized electron-positron-ion plasma with superthermal electrons is studied. Linear dispersion relations of the fast and slow ion-acoustic modes are discussed under the weak and strong magnetic field situations. By means of the reductive perturbation approach, Korteweg-de Vries equations governing ion-acoustic waves of fast and slow modes are derived, respectively. Explicit interacting soliton-cnoidal wave solutions are obtained by the generalized truncated Painlevé expansion. It is found that every peak of a cnoidal wave elastically interacts with a usual soliton except for some phase shifts. The influence of the electron superthermality, positron concentration, and magnetic field obliqueness on the soliton-cnoidal wave are investigated in detail. [ABSTRACT FROM AUTHOR]

We investigate the (2+1)-dimensional nonlinear BKP and GKP equations with the modified direct CK's method. Then, we get its Lie point groups and the full symmetry group, and a relationship is constructed between the newsolutions and the old one. Based on the relationship, the new solutions can be obtained by using a given solution of the equations. [ABSTRACT FROM AUTHOR]

Let C be a closed bounded convex subset of a real Banach space X with 0 as its interior and PC the Minkowski functional generated by the set C. For a nonempty set G in X and x ∊ X, g0 ∊ G is called the generalized best approximation to x from G if PC(g0-x) = PC(g - x) for all g ∊ G. In this paper, we will give a distance formula under PC from a point to a closed hyperplane H(x*, α) in X determined by a nonzero continuous linear functional x* in X and a real number α, a representation of the generalized metric projection onto H(x*, α), and investigate the continuity of this generalized metric projection, extending corresponding results for the case of norm. [ABSTRACT FROM AUTHOR]

The metric form Ω(f, λ) , which was introduced by Zeng and Cheng in [8], plays an important role in the estimate of pointwise approximation of functions which have left limit f(χ-) and right limit f(χ+) at given point χ. In this paper , Using the metric form Ωχ(f, λ) and the Bojanic - Khan - Cheng's method combining with analysis techniques , we obtain the asymptotic estimates on the rates of pointwise approximation of Gauss-Weierstrass operators on two classes of functions with certain growth condition. [ABSTRACT FROM AUTHOR]

In this article we study the pointwise approximation of the Modified Baskakov operators for functions of bounded variation. By means of the techniques of [J. Approx. Theory 102 (2000), 1-12] and some probabilistic methods, we obtain an estimate formula on this type approximation. Our result corrects the mistaken estimate in [2,Demonstratio Math. 30 (1997), 339-346]. [ABSTRACT FROM AUTHOR]

Retroviral integrase, an essential enzyme for replication of human immunodeficiency virus type-1 (HIV-1) and other retroviruses, contains three structurally distinct domains, an N-terminal domain, the catalytic core and a C-terminal domain. To elucidate their spatial arrangement, we have solved the structure of a fragment of HIV-1 integrase comprising the N-terminal and catalytic core domains. This structure reveals a dimer interface between the N-terminal domains different from that observed for the isolated domain. It also complements the previously determined structure of the C-terminal two domains of HIV-1 integrase; superposition of the conserved catalytic core of the two structures results in a plausible full-length integrase dimer. Furthermore, an integrase tetramer formed by crystal lattice contacts bears structural resemblance to a related bacterial transposase, Tn5, and exhibits positively charged channels suitable for DNA binding. [ABSTRACT FROM AUTHOR]

The supersymmetric extensions of two integrable systems, a special negative Kadomtsev–Petviashvili (NKP) system and a (2+1)-dimensional modified Korteweg–de Vries (MKdV) system, are constructed from the Hirota formalism in the superspace. The integrability of both systems in the sense of possessing infinitely many generalized symmetries are confirmed by extending the formal series symmetry approach to the supersymmetric framework. It is found that both systems admit a generalization of type algebra and a Kac-Moody–Virasoro type subalgebra. Interestingly, the first one of the positive flow of the supersymmetric NKP system is another supersymmetric extension of the (2+1)-dimensional MKdV system. Based on our work, a hypothesis is put forward on a series of (2+1)-dimensional supersymmetric integrable systems. It is hoped that our work may develop a straightforward way to obtain supersymmetric integrable systems in high dimensions. [ABSTRACT FROM AUTHOR]

Background: Paroxetine, a selective serotonin reuptake inhibitor for counteracting depression, has been recently suggested as having a role in prevention of dopaminergic neuronal degeneration in substantia nigra, a hallmark of Parkinson's disease (PD). The pathogenesis of this type of neurological disorders often involves the activation of microglia and associated inflammatory processes. Thus in this study we aimed to understand the role of paroxetine in microglia activation and to elucidate the underlying mechanism(s). Methods: BV2 and primary microglial cells were pretreated with paroxetine and stimulated with lipopolysaccharide (LPS). Cells were assessed for the responses of pro-inflammatory mediator and cytokines, and the related signaling pathways were evaluated and analyzed in BV2 cells. Results: Paroxetine significantly inhibited LPS-induced production of nitric oxide (NO) and pro-inflammatory cytokines such as TNF-α and IL-1β. Further analysis showed inducible nitric oxide synthase (iNOS) and mRNA expression of TNF-α and IL-1β were attenuated by paroxetine pretreatment. Analyses in signaling pathways demonstrated that paroxetine led to suppression of LPS-induced JNK1/2 activation and baseline ERK1/2 activity, but had little effect on the activation of p38 and p65/NF-κB. Interference with specific inhibitors revealed that paroxetine-mediated suppression of NO production was via JNK1/2 pathway while the cytokine suppression was via both JNK1/2 and ERK1/2 pathways. Furthermore, conditioned media culture showed that paroxetine suppressed the microglia-mediated neurotoxicity. Conclusions: Paroxetine inhibits LPS-stimulated microglia activation through collective regulation of JNK1/2 and ERK1/2 signaling. Our results indicate a potential role of paroxetine in neuroprotection via its anti-neuroinflammatory effect besides targeting for depression. [ABSTRACT FROM AUTHOR]

A special nonlocal symmetry related to the Bäcklund transformation is obtained for the (1+1)-dimensional sine-Gordon (sG) equation in its polynomial form, which can further generate infinitely many nonlocal symmetries of the sG equation due to the inclusion of an arbitrary spectrum parameter. This nonlocal symmetry can be localized, and hence turn into a point symmetry for the augmented system through the introduction of an auxiliary function. Consequently, finite transformation, similarity reductions, and explicit invariant solutions related to the nonlocal symmetry are obtained. It is known that the sG equation has topological solitons or kinks (or antikinks). Based on the group invariant solutions, a different kind of topological soliton, which is a topological soliton situated on a cnoidal wave background, is obtained analytically and graphically displayed. [ABSTRACT FROM AUTHOR]

Adult stem cells (ASCs) capable of self-renewal and differentiation confer the potential of tissues to regenerate damaged parts. Epigenetic regulation is essential for driving cell fate decisions by rapidly and reversibly modulating gene expression programs. However, it remains unclear haw epigenetic factors elicit ASC-driven regeneration. In this paper, we report that an RNA interference screen against 205 chromatin regulators identified 12 proteins essential for ASC function and regeneration in planarians. Surprisingly, the HP1-like protein SMED-HP1-1 (HP1-1) specifically marked self-renewing, pluripotent ASCs, and HP1-1 depletion abrogated self-renewal and promoted differentiation. Upon injury, HP1-1 expression increased and elicited increased ASC expression of Mcm5 through functional association with the FACT (facilitates chromatin transcription) complex, which consequently triggered proliferation of ASCs and initiated blastema formation. Our observations uncover an epigenetic network underlying ASC regulation in planarians and reveal that an HP1 protein is a key chromatin factor controlling stem cell function. These results provide important insights into how epigenetic mechanisms orchestrate stem cell responses during tissue regeneration. [ABSTRACT FROM AUTHOR]

Pd(II)-catalyzed enantioselective C-H activation of phenylacetic acids followed by an intramolecular C-O bond formation afforded chiral benzofuranones. This reaction provides the first example of enantioselecctive C-H functionalizations through Pd(II)/Pd(IV) redox catalysis. [ABSTRACT FROM AUTHOR]

A new concept, called the row—column visibility graph, is proposed to map two-dimensional landscapes to complex networks. A cluster coverage is introduced to describe the extensive property of node clusters on a Euclidean lattice. Graphs mapped from fractals generated with the probability redistribution model behave scale-free. They have pattern-induced hierarchical organizations and comparatively much more extensive structures. The scale-free exponent has a negative correlation with the Hurst exponent, however, there is no deterministic relation between them. Graphs for fractals generated with the midpoint displacement model are exponential networks. When the Hurst exponent is large enough (e.g., H > 0.5), the degree distribution decays much more slowly, the average coverage becomes significant large, and the initially hierarchical structure at H < 0.5 is destroyed completely. Hence, the row—column visibility graph can be used to detect the pattern-related new characteristics of two-dimensional landscapes. [ABSTRACT FROM AUTHOR]