Beschreibung: The title complexes, poly[[bis[μ 2 -2-ethyl-1-(pyridin-3-ylmethyl)-1 H -benzimidazole-κ 2 N 1 : N 3 ]copper(I)] tetrafluoroborate acetonitrile monosolvate], {[Cu(C 15 H 15 N 3 ) 2 ]BF 4 ·CH 3 CN} n , (I), and poly[[bis[μ 2 -2-ethyl-1-(pyridin-3-ylmethyl)-1 H -benzimidazole-κ 2 N 1 : N 3 ]silver(I)] perchlorate methanol monosolvate], {[Ag(C 15 H 15 N 3 ) 2 ]ClO 4 ·CH 3 OH} n , (II), are isostructural and exhibit one-dimensional ladder-like structures in which each asymmetric unit contains one metal ion (Cu + or Ag + ), two 2-ethyl-1-(pyridin-3-ylmethyl)-1 H -benzimidazole (bep) ligands, one counter-anion (tetrafluoroborate or perchlorate) and one interstitial molecule (acetonitrile or methanol). Each metal ion exhibits a distorted tetrahedral coordination geometry consisting of two pyridyl and two benzimidazole N atoms from four distinct ligands. Two metal ions are linked by two bep ligands to form a centrosymmetric 18-membered M 2 (bep) 2 metallacycle, while adjacent M 2 (bep) 2 metallacycles are further interlinked by another two bep ligands resulting in a ladder-like array. In the extended structure, four adjacent ladder-like arrays are connected together through C—H...F, O—H...O and C—H...O hydrogen bonds between bep ligands, solvent molecules and counter-anions into a three-dimensional supramolecular structure.

Beschreibung: Coordination polymer with an 8-connected topology and selective adsorption properties. Hua-Hong Zou, Yan-Ping He, Liu-Cheng Gui, Fu-Pei Liang ( from CrystEngComm) Hua-Hong Zou, CrystEngComm, 2011, DOI: 10.1039/C1CE05103B To cite this article before page numbers are assigned, use the DOI form of citation above. The content of this RSS Feed (c) The Royal Society of Chemistry

Beschreibung: Y. Cai & H. Hua comment: Zhuravlev, Gamez Vintaned & Ivantsov (2009) reported the problematic Ediacaran fossil Gaojiashania annulucosta in Siberia and they considered that this is the first find of Gaojiashania outside China, since Gaojiashania had previously only been reported from the Gaojiashan Member of the middle Dengying Formation in the Ningqiang area, southern Shaanxi Province, South China. However, we believe that the so-called Siberian Gaojiashania was mis-identified, and what was described as Gaojiashania annulucosta by Zhuravlev, Gamez Vintaned & Ivantsov (2009) is more appropriately ascribed to Shaanxilithes ningqiangensis, another problematic Ediacaran fossil that has also been known from the Gaojiashan Member in Shaanxi Province of South China (Chen, Chen & Lao, 1975; Xing et al. 1984), as well as the stratigraphically equivalent Taozichong Formation in Guizhou Province (Hua, Chen & Zhang, 2004) and the Jiucheng Member (Dengying Formation) in Yunnan Province of South China (Zhu & Zhang, 2005), the Zhoujieshan Formation in Qinghai Province (Shen et al. 2007), and the Zhengmuguan Formation in Ningxia Hui Autonomous Region of North China (Shen et al. 2007).

Beschreibung: Background: Chinese fir (Cunninghamia lanceolata) is an important timber species that accounts for 20--30% of the total commercial timber production in China. However, the available genomic information of Chinese fir is limited, and this severely encumbers functional genomic analysis and molecular breeding in Chinese fir. Recently, major advances in transcriptome sequencing have provided fast and cost-effective approaches to generate large expression datasets that have proven to be powerful tools to profile the transcriptomes of non-model organisms with undetermined genomes. Results: In this study, the transcriptomes of nine tissues from Chinese fir were analyzed using the Illumina HiSeqTM 2000 sequencing platform. Approximately 40 million paired-end reads were obtained, generating 3.62 gigabase pairs of sequencing data. These reads were assembled into 83,248 unique sequences (i.e. Unigenes) with an average length of 449 bp, amounting to 37.40 Mb. A total of 73,779 Unigenes were supported by more than 5 reads, 42,663 (57.83%) had homologs in the NCBI non-redundant and Swiss-Prot protein databases, corresponding to 27,224 unique protein entries. Of these Unigenes, 16,750 were assigned to Gene Ontology classes, and 14,877 were clustered into orthologous groups. A total of 21,689 (29.40%) were mapped to 119 pathways by BLAST comparison against the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The majority of the genes encoding the enzymes in the biosynthetic pathways of cellulose and lignin were identified in the Unigene dataset by targeted searches of their annotations. And a number of candidate Chinese fir genes in the two metabolic pathways were discovered firstly. Eighteen genes related to cellulose and lignin biosynthesis were cloned for experimental validating of transcriptome data. Overall 49 Unigenes, covering different regions of these selected genes, were found by alignment. Their expression patterns in different tissues were analyzed by qRT-PCR to explore their putative functions. Conclusions: A substantial fraction of transcript sequences was obtained from the deep sequencing of Chinese fir. The assembled Unigene dataset was used to discover candidate genes of cellulose and lignin biosynthesis. This transcriptome dataset will provide a comprehensive sequence resource for molecular genetics research of C. lanceolata.

Beschreibung: Journal of the American Chemical Society DOI: 10.1021/ja303702n

Beschreibung: Shaanxilithes ningqiangensis is an enigmatic ribbon-shaped fossil from the upper Ediacaran Gaojiashan Member of the Dengying Formation, southern Shaanxi Province, South China. This taxon has also been reported from Ediacaran successions in North China and possibly in Siberia, making it a potential index fossil for interregional biostratigraphic correlation of upper Ediacaran successions. At Gaojiashan, Shaanxilithes ningqiangensis is often preserved along bedding planes of phosphate-rich silty and calcareous shale, with no evidence of vertical intrusion into adjacent beds and containing little to no carbonaceous material. Here, through detailed microstructural and microchemical investigation using a combination of analytical techniques, taphonomic details of Shaanxilithes ningqiangensis and potentially related forms are revealed, showing that these enigmatic fossils are preserved as clay molds. Together with other taphonomic features, such as abruptly bent ribbons, overlapping but not crosscutting ribbons, and co-occurring discoidal structures interpreted as disarticulated sections of the original organism, the new data suggest that Shaanxilithes ningqiangensis is a body fossil consisting of serially arranged units that are discoidal, lensoidal, or crescentic in shape. Shaanxilithes ningqiangensis is not a trace fossil as some previous researchers have suggested.

Beschreibung: Background: The proceeding of blood pressure (BP) from normal level to the hypertension has been found to be associated with increased cardiovascular events and multiple vascular risk factors. However, whether the process is associated with increased carotid atherosclerotic plaque per se or not is still unclear. Methods: Nine hundred and forty-two participants aged from 46 to 75 were enrolled from community population in Southern China. Their metabolic risk factors, carotid intima-media thickness (cIMT) and atherosclerotic plaque formation were analyzed and stratified by different blood pressure levels according to JNC-7 or ESH/ESC-2007 classification. Results: From low BP level to higher BP level, multiple metabolic risk factors increased linearly. Prehypertension in JNC-7 classification (or normal BP and high normal BP in ESH/ESC-2007 classification) was correlated with thicker cIMT and more plaque formation than normotension (or optimal BP) (p 〈 0.001). After adjusting multiple metabolic factors, the differences were still significant (p 〈 0.05). Furthermore, prehypertensive participants had a trend to be thicker carotid IMT (OR and its 95% CI: 1.65, 0.97-2.82, p = 0.067) and significantly higher carotid plaque occurrence (OR and its 95% CI: 2.36, 1.43-3.88, p = 0.001) than normotensive ones. However, there was no significant difference of cIMT and plaque formation between normal BP and high normal BP (p 〉 0.05). Thus, we concluded that plaque formation in prehypertension was as significant as that in hypertension. Conclusion: Prehypertension is associated with significantly increased carotid atherosclerotic plaque and is a primary stratify risk factor for carotid atherosclerosis which could cause ischemic stroke in middle-aged and elderly population in Southern China.

Beschreibung: Top–down fabrication of sub-nanometre semiconducting nanoribbons derived from molybdenum disulfide sheets Nature Communications 4, 1776 (2013). doi:10.1038/ncomms2803 Authors: Xiaofei Liu, Tao Xu, Xing Wu, Zhuhua Zhang, Jin Yu, Hao Qiu, Jin-Hua Hong, Chuan-Hong Jin, Ji-Xue Li, Xin-Ran Wang, Li-Tao Sun & Wanlin Guo

Beschreibung: Hepatocellular carcinoma (HCC) is one of the most prevalent cancers and is rising in incidence worldwide. The molecular mechanisms leading to the development of HCC are complex and include both genetic and epigenetic events. To determine the relative contribution of these alterations in liver tumorigenesis, we evaluated epigenetic modifications at both global and gene specific levels, as well as the mutational profile of genes commonly altered in liver tumors. A mouse model of fibrosis-associated liver cancer that was designed to emulate cirrhotic liver, a prevailing disease state observed in most humans with HCC, was used. Tumor and non-tumor liver samples from B6C3F1 mice treated with N -nitrosodiethylamine (DEN; a single ip injection of 1 mg/kg at 14 days of age) and carbon tetrachloride (CCl 4 ; 0.2 ml/kg, 2 times/week ip starting at 8 weeks of age for 14 weeks), as well as corresponding vehicle control animals, were analyzed for genetic and epigenetic alterations. H-ras , Ctnnb1 , and Hnf1α genes were not mutated in tumors in mice treated with DEN+CCl 4 . In contrast, the increased tumor incidence in mice treated with DEN+CCl 4 was associated with marked epigenetic changes in liver tumors and non-tumor liver tissue, including demethylation of genomic DNA and repetitive elements, a decrease in histone 3 lysine 9 trimethylation (H3K9me3), and promoter hypermethylation and functional down-regulation of Riz1, a histone lysine methyltransferase tumor suppressor gene. Additionally, the reduction in H3K9me3 was accompanied by increased expression of long interspersed nucleotide elements (LINE) 1 and short interspersed nucleotide elements (SINE) B2, which is an indication of genomic instability. In summary, our results suggest that epigenetic events, rather than mutations in known cancer-related genes, play a prominent role in increased incidence of liver tumors in this mouse model of fibrosis-associated liver cancer. © 2013 Wiley Periodicals, Inc.