Osthole represses growth of multiple myeloma cells by regulating PI3K/AKT and ERK pathways

Purpose: To identify the effects of osthole on the growth of multiple myeloma cells and determine the probable molecular mechanism of action. Methods: 3-(4, 5-Dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay was used to measure multiple myeloma cell viability. Flow cytometry was used for the evaluation of cell cycle and apoptosis. For protein expression measurement, western blot analysis was employed. Results: The results show that osthole dose- and time-dependently suppressed the viability of multiple myeloma cells (p < 0.01). Osthole also dose-dependently initiated multiple myeloma cell cycle arrest in G0/G1 phase (p < 0.05) and induced multiple myeloma cell apoptosis (p < 0.01). Moreover, western blotting revealed a significant reduction in cyclin D1 (p < 0.01) and induction in p21, cleaved caspase 3 and cleaved poly (ADP-ribose) polymerase (p < 0.01). Furthermore, osthole treatment significantly downregulated the phosphorylation levels of protein kinase B (AKTT308), AKTS473, and extracellular regulated protein kinase 1/2 (ERK1/2). Conclusion: These findings demonstrated that osthole inhibited viability and induced cell cycle arrest and apoptosis of multiple myeloma cells by regulating PI3K/AKT and ERK pathways. Osthole may be considered as a potential anticancer agent for the therapy of multiple myeloma

Nonlinear dielectric geometric-phase metasurface with simultaneous structure and lattice symmetry design

In this work, we utilize thin dielectric meta-atoms placed on a silver substrate to efficiently enhance and manipulate the third harmonic generation. We theoretically and experimentally reveal that when the structural symmetry of the meta-atom is incompatible with the lattice symmetry of an array, some generalized nonlinear geometric phases appear, which offers new possibilities for harmonic generation control beyond the accessible symmetries governed by the selection rule. The underlying mechanism is attributed to the modified rotation of the effective principal axis of a dense meta-atom array, where the strong coupling among the units gives rise to a generalized linear geometric phase modulation on the pump light. Therefore, nonlinear geometric phases carried by the third-harmonic emissions are the natural result of the wave-mixing process among the modes excited at the fundamental frequency. This mechanism further points out a new strategy to predict the nonlinear geometric phases delivered by the nanostructures according to their linear responses. Our design is simple and efficient, and offers alternatives for the nonlinear meta-devices that are capable of flexible photon generation and manipulation

Design of FPGA-Implemented Reed-Solomon Erasure Code (RS-EC) Decoders With Fault Detection and Location on User Memory

Reed–Solomon erasure codes (RS-ECs) are widely used in packet communication and storage systems to recover erasures. When the RS-EC decoder is implemented on a field-programmable gate array (FPGA) in a space platform, it will suffer single-event upsets (SEUs) that can cause failures. In this article, the reliability of an RS-EC decoder implemented on an FPGA when there are errors in the user memory is first studied. Then, a fault detection and location scheme is proposed based on partial reencoding for the faults in the user memory of the RS-EC decoder. Furthermore, check bits are added in the generator matrix to improve the fault location performance. The theoretical analysis shows that the scheme could detect most faults with small missing and false detection probability. Experimental results on a case study show that more than 90% of the faults on user memory could be tolerated by the decoder, and all the other faults can be detected by the fault detection scheme when the number of erasures is smaller than the correction capability of the code. Although false alarms exist (with probability smaller than 4%), they can be used to avoid fault accumulation. Finally, the fault location scheme could accurately locate all the faults. The theoretical estimates are very close to the experiment results, which verifies the correctness of the analysis done.This work was supported in part by the National Natural Science Foundation of China under Grant 61501321, in part by the China Postdoctoral Science Foundation and Luoyang Newvid Technology Company, Ltd., and in part by the ACHILLES Project PID2019-104207RB-I00 funded by the Spanish Ministry of Science and Innovation

Cognition Impairment Prior to Errors of Working Memory Based on Event-Related Potential

Cognitive impairment contributes to errors in different tasks. Poor attention and poor cognitive control are the two neural mechanisms for performance errors. A few studies have been conducted on the error mechanism of working memory. It is unclear whether the changes in memory updating, attention, and cognitive control can cause errors and, if so, whether they can be probed at the same time in one single task. Therefore, this study analyzed event-related potentials in a two-back working memory task. A total of 40 male participants finished the task. The differences between the error and the correct trials in amplitudes and latencies of N1, P2, N2, and P3 were analyzed. The P2 and P3 amplitudes decreased significantly in the error trials, while the N2 amplitude increased. The results showed that impaired attention, poor memory updating, and impaired cognitive control were consistently associated with the error in working memory. Furthermore, the results suggested that monitoring the neurophysiological characteristics associated with attention and cognitive control was important for studying the error mechanism and error prediction. The results also suggested that the P3 and N2 amplitudes could be used as indexes for error foreshadowing

Genetic diversity of Ophiocordyceps sinensis, a medicinal fungus endemic to the Tibetan Plateau: Implications for its evolution and conservation

<p>Abstract</p> <p>Background</p> <p><it>Ophiocordyceps sinensis </it>(syn. <it>Cordyceps sinensis</it>), endemic to alpine regions on the Tibetan plateau, is one of the most valuable medicinal fungi in the world. Huge commercial demand has led to excessive harvest and a dramatic decline in its numbers. The diversity of terrains and climates on the Tibetan Plateau and the broad insect host range (more than 50 species in the family Hepialidae) may have resulted in substantial intraspecific genetic diversity for this fungus. The objective of this study was to evaluate the population distribution of <it>O. sinensis </it>from geographically diverse regions of the Tibetan Plateau based on nrDNA ITS and <it>MAT1-2-1 </it>gene sequences. Understanding of the genetic diversity and genesis of <it>O. sinensis </it>will provide important information for the evolution and conservation of this fungus.</p> <p>Results</p> <p>Significant sequence variations in the ITS and <it>MAT1-2-1 </it>genes (27 and 23 informative sites, eight and seven haplotypes, respectively) were observed. Phylogenetic analysis based on ITS sequences, <it>MAT1-2-1 </it>sequences, or their combined data set, clustered isolates from northern regions in one clade (clade I), whereas isolates from southern regions were dispersed in all four clades (clade I-IV). Single-strand conformation polymorphism (SSCP) analyses of 2639 ITS clones from seven samples revealed 91 different SSCP patterns that were subsequently sequenced. ITS heterogeneity was found in XZ-LZ07-H1 (Nyingchi population), and 17 informative sites and five haplotypes were detected from 15 clones. The five haplotypes clustered into three clades (clade I, II, and IV).</p> <p>Conclusions</p> <p>Significant genetic divergence in <it>O. sinensis </it>was observed and the genetic diversification was greater among southern isolates than that among northern isolates. The polymorphism of nrDNA ITS sequences suggested that <it>O. sinensis </it>spread from a center of origin (the Nyingchi District) to southern regions and subsequently to northern areas. These results suggest that southern populations are important reservoirs of genetic diversity and should be taken into account in conservation programs.</p

A Grey NGM

Energy consumption prediction is an important issue for governments, energy sector investors, and other related corporations. Although there are several prediction techniques, selection of the most appropriate technique is of vital importance. As for the approximate nonhomogeneous exponential data sequence often emerging in the energy system, a novel grey NGM(1,1,k) self-memory coupling prediction model is put forward in order to promote the predictive performance. It achieves organic integration of the self-memory principle of dynamic system and grey NGM(1,1,k) model. The traditional grey model’s weakness as being sensitive to initial value can be overcome by the self-memory principle. In this study, total energy, coal, and electricity consumption of China is adopted for demonstration by using the proposed coupling prediction technique. The results show the superiority of NGM(1,1,k) self-memory coupling prediction model when compared with the results from the literature. Its excellent prediction performance lies in that the proposed coupling model can take full advantage of the systematic multitime historical data and catch the stochastic fluctuation tendency. This work also makes a significant contribution to the enrichment of grey prediction theory and the extension of its application span