Regulation of AMPA receptors in spinal nociception

The functional properties of α-amino-3-hydroxy-5-methy-4-isoxazole propionate (AMPA) receptors in different brain regions, such as hippocampus and cerebellum, have been well studied in vitro and in vivo. The AMPA receptors present a unique characteristic in the mechanisms of subunit regulation during LTP (long-term potentiation) and LTD (long-term depression), which are involved in the trafficking, altered composition and phosphorylation of AMPA receptor subunits. Accumulated data have demonstrated that spinal AMPA receptors play a critical role in the mechanism of both acute and persistent pain. However, less is known about the biochemical regulation of AMPA receptor subunits in the spinal cord in response to painful stimuli. Recent studies have shown that some important regulatory processes, such as the trafficking of AMPA receptor subunit, subunit compositional changes, phosphorylation of AMPA receptor subunits, and their interaction with partner proteins may contribute to spinal nociceptive transmission. Of all these regulation processes, the phosphorylation of AMPA receptor subunits is the most important since it may trigger or affect other cellular processes. Therefore, these study results may suggest an effective strategy in developing novel analgesics targeting AMPA receptor subunit regulation that may be useful in treating persistent and chronic pain without unacceptable side effects in the clinics

Ionospheric VTEC anomalies before Ms7.1 Yushu earthquake

Abstract:Vertical total electron content is examined to check whether the Ms7.1 Yushu earthquake on April 14, 2010, may have caused any anomalous ionospheric changes. The result shows two TEC increases over the epicenter vicinity on April 1 and 5; these anomalies drifted from east to west, the latter across the whole China. The increase on April 5 was probably related to geomagnetic activity, whereas the one on April 1 may possibly be related to the Yushu earthquake

Reflection on the Experiences of US and European Automobile Industry to Hubei’s Future Development

Surpassing the US in car sales in 2009. China has, since the world financial crisis, been showing big potential while US automobiles industry under complete depression. Green car, which has long been popular in European countries such as Belgium, has therefore become a key for the revival of the world car industry. As one of the three major automobile bases in China, how can Hubei benefit from the current challenge and development opportunity in the pro-crisis era?Key words: Saving and new energy vehicles; US automobile; decay; European “green” plastics; Hubei; developmen

HIF-1α Contributes to Hypoxia-induced Invasion and Metastasis of Esophageal Carcinoma via Inhibiting E-cadherin and Promoting MMP-2 Expression

Hypoxia-inducible factor-1α (HIF-1α) has been found to enhance tumor invasion and metastasis, but no study has reported its action in esophageal carcinoma. The goal of this study was to explore the probable mechanism of HIF-1α in the invasion and metastasis of esophageal carcinoma Eca109 cells in vitro and in vivo. mRNA and protein expression of HIF-1α, E-cadherin and matrix metalloproteinase-2 (MMP-2) under hypoxia were detected by RT-PCR and Western blotting. The effects of silencing HIF-1α on E-cadherin, MMP-2 mRNA and protein expression under hypoxia or normoxia were detected by RT-PCR and Western blotting, respectively. The invasive ability of Eca109 cells was tested using a transwell chambers. We established an Eca109-implanted tumor model and observed tumor growth and lymph node metastasis. The expression of HIF-1α, E-cadherin and MMP-2 in xenograft tumors was detected by Western blotting. After exposure to hypoxia, HIF-1α protein was up-regulated, both mRNA and protein levels of E-cadherin were down-regulated and MMP-2 was up-regulated, while HIF-1α mRNA showed no significant change. SiRNA could block HIF-1α effectively, increase E-cadherin expression and inhibit MMP-2 expression. The number of invading cells decreased after HIF-1α was silenced. Meanwhile, the tumor volume was much smaller, and the metastatic rate of lymph nodes and the positive rate were lower in vivo. Our observations suggest that HIF-1α inhibition might be an effective strategy to weaken invasion and metastasis in the esophageal carcinoma Eca109 cell line

Approaches to the Total Synthesis of Puupehenone-Type Marine Natural Products

Puupehenones have been isolated from the marine sponge Chondrosia chucalla, which belong to a growing family of natural products with more than 100 members. These marine natural products have attracted increasing attention mainly due to their wide variety of biological activities such as antitumor, antiviral, and anti-HIV, and thus offer promising opportunities for new drug development. This chapter covers the approaches to the total synthesis of puupehenone-type marine natural products including puupehenol, puupehenone, puupehedione, and halopuupehenones. The routes begin with the construction of their basic skeletons, followed by the modification of their C- and D-rings. The contents are divided into two sections in terms of the key strategies employed to construct the basic skeleton. One is the convergent synthesis route with two synthons coupled by nucleophilic or electrophilic reaction, and the other is the linear synthesis route with polyene series cyclization as a key reaction

Bis[N,N-bis­(1-allyl-1H-benzimidazol-2-ylmethyl-κN 3)benzyl­amine-κN]cadmium dipicrate

The crystal structure of the title compound, [Cd(C29H29N5)2](C6H2N3O7)2, consists of CdII complex cations and picrate anions. In the complex cation, the CdII ion is chelated by two bis­(1-allyl­benzimidazol-2-ylmeth­yl)benzyl­amine (babb) ligands in a distorted octa­hedral geometry. Extensive C—H⋯O hydrogen bonding occurs between cations and anions in the crystal structure

Methods for simultaneously identifying coherent local clusters with smooth global patterns in gene expression profiles

<p>Abstract</p> <p>Background</p> <p>The hierarchical clustering tree (HCT) with a dendrogram <abbrgrp><abbr bid="B1">1</abbr></abbrgrp> and the singular value decomposition (SVD) with a dimension-reduced representative map <abbrgrp><abbr bid="B2">2</abbr></abbrgrp> are popular methods for two-way sorting the gene-by-array matrix map employed in gene expression profiling. While HCT dendrograms tend to optimize local coherent clustering patterns, SVD leading eigenvectors usually identify better global grouping and transitional structures.</p> <p>Results</p> <p>This study proposes a flipping mechanism for a conventional agglomerative HCT using a rank-two ellipse (R2E, an improved SVD algorithm for sorting purpose) seriation by Chen <abbrgrp><abbr bid="B3">3</abbr></abbrgrp> as an external reference. While HCTs always produce permutations with good local behaviour, the rank-two ellipse seriation gives the best global grouping patterns and smooth transitional trends. The resulting algorithm automatically integrates the desirable properties of each method so that users have access to a clustering and visualization environment for gene expression profiles that preserves coherent local clusters and identifies global grouping trends.</p> <p>Conclusion</p> <p>We demonstrate, through four examples, that the proposed method not only possesses better numerical and statistical properties, it also provides more meaningful biomedical insights than other sorting algorithms. We suggest that sorted proximity matrices for genes and arrays, in addition to the gene-by-array expression matrix, can greatly aid in the search for comprehensive understanding of gene expression structures. Software for the proposed methods can be obtained at <url>http://gap.stat.sinica.edu.tw/Software/GAP</url>.</p

Di-μ-sulfato-κ4 O:O′-bis­[diaqua­(1H-imidazo[4,5-f][1,10]phenanthroline-κ2 N 7,N 9)cobalt(II)] dihydrate

In the centrosymmetric dinuclear title compound, [Co2(SO4)2(C13H8N4)2(H2O)4]·2H2O, the CoII atom is coord­in­ated by two N atoms from two 1H-imidazo[4,5-f][1,10]phenanthroline ligands, two O atoms from two sulfate anions and two O atoms from water mol­ecules in a distorted octa­hedral geometry. The Co⋯Co separation is 5.1167 (7) Å. The coordinated and uncoordinated water mol­ecules engage in N—H⋯O and O—H⋯O hydrogen-bonding inter­actions