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871.

Background

Recent studies demonstrated that long non-coding RNAs (lncRNAs) could be intricately implicated in cancer-related molecular networks, and related to cancer occurrence, development and prognosis. However, clinicopathological and molecular features for these cancer-related lncRNAs, which are very important in bridging lncRNA basic research with clinical research, fail to well settle to integration.

Results

After manually reviewing more than 2500 published literature, we collected the cancer-related lncRNAs with the experimental proof of functions. By integrating from literature and public databases, we constructed CRlncRNA, a database of cancer-related lncRNAs. The current version of CRlncRNA embodied 355 entries of cancer-related lncRNAs, covering 1072 cancer-lncRNA associations regarding to 76 types of cancer, and 1238 interactions with different RNAs and proteins. We further annotated clinicopathological features of these lncRNAs, such as the clinical stages and the cancer hallmarks. We also provided tools for data browsing, searching and download, as well as online BLAST, genome browser and gene network visualization service.

Conclusions

CRlncRNA is a manually curated database for retrieving clinicopathological and molecular features of cancer-related lncRNAs supported by highly reliable evidences. CRlncRNA aims to provide a bridge from lncRNA basic research to clinical research. The lncRNA dataset collected by CRlncRNA can be used as a golden standard dataset for the prospective experimental and in-silico studies of cancer-related lncRNAs. CRlncRNA is freely available for all users at http://crlnc.xtbg.ac.cn.
  相似文献   
872.
In regulated rivers, fluctuating water depths associated with pulsed discharges may strand small fish in side channels and pools. Quantitative assessments of stranded fish are difficult in field studies (e.g., due to unknown effects of avian and terrestrial vertebrate predators). To assess such lateral displacement and stranding on juvenile stream fishes, we designed, constructed, and tested (with three species) a 2 × 1-m, lateral-displacement flume. The flume featured a main channel that never drained and a raised, wide “floodplain” channel that alternately flooded, with a simulated pulse, and became dewatered. The floodplain contained four pools, with different shapes and draining capacities, in which fish could become stranded as the water level subsided. Fish-stranding rates (8%) in this relatively compact laboratory flume, after exposure to simulated pulsed stream flows, were comparable to those observed in past investigations using larger, artificial streams.  相似文献   
873.
A species distribution combines the resources and climatic tolerances that allow an individual or population to persist. As these conditions change, one mechanism to maintain favorable resources is for an organism to shift its range. Much of the research examining range shifts has focused on dynamic distribution boundaries wheras the role of species breeding habitat or migration strategies on shift tendencies has received less attention. We expand on previous research by using a large suite of avian species (i.e., 277), analyzing observed abundance-weighted average latitudes, and categorizing species by breeding environment and migration strategy. We used the North American Breeding Bird Survey dataset to address two questions: (1) Has the center of observed abundance for individual species shifted latitudinally? (2) Is there a relationship between migration strategy or breeding habitat and range shifts? Results indicate the majority of species have experienced poleward range shifts over the last 43 years, and birds breeding in all habitat showed trends of poleward shift but only those species breeding in scrub-shrub and grassland environments were different from zero. Additionally, species that are short distance migrants are experiencing significant poleward shifts while Neotropical and permanent residents had shifts that were not different from zero. Our findings do support the general trend expected from climate driven changes (i.e., > 52 % shifting poleward), however, the proportion of species exhibiting equatorial shifts (24 %) or no significant shifts (23 %) illustrates the complex interplay between land cover, climate, species interactions, and other forces that can interact to influence breeding ranges over time. Regardless of the mechanisms driving range shifts, our findings emphasize the need for connecting and expanding habitats for those species experiencing range shifts. This research describes the patterns of breeding birds through central North America and we encourage future research to focus on the mechanisms driving these patterns.  相似文献   
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876.
Aluminum is associated with etiology of many neurodegenerative diseases specially Alzheimer’s disease. Chronic exposure to aluminum via drinking water results in aluminum deposition in the brain that leads to cognitive deficits. The study aimed to determine the effects of aluminum on cholinergic biomarkers, i.e., acetylcholine level, free choline level, and choline acetyltransferase gene expression, and how cholinergic deficit affects novel object recognition and sociability in mice. Mice were treated with AlCl3 (250 mg/kg). Acetylcholine level, free choline level, and choline acetyltransferase gene expression were determined in cortex, hippocampus, and amygdala. The mice were subjected to behavior tests (novel object recognition and social novelty preference) to assess memory deficits. The acetylcholine level in cortex and hippocampus was significantly reduced in aluminum-treated animals, as compared to cortex and hippocampus of control animals. Acetylcholine level in amygdala of aluminum-treated animals remained unchanged. Free choline level in all the three brain parts was found unaltered in aluminum-treated mice. The novel object recognition memory was severely impaired in aluminum-treated mice, as compared to the control group. Similarly, animals treated with aluminum showed reduced sociability compared to the control mice group. Our study demonstrates that aluminum exposure via drinking water causes reduced acetylcholine synthesis in spite of normal free choline availability. This deficit is caused by reduced recycling of acetylcholine due to lower choline acetyltransferase level. This cholinergic hypofunction leads to cognitive and memory deficits. Moreover, hippocampus is the most affected brain part after aluminum intoxication.  相似文献   
877.
The prokaryotic diversity associated with organic household waste (OHW), leachate (start-up inoculum), and mesophilic anaerobic digestion processes in the degradation of OHW for 44 and 90 days was investigated using a culture-independent approach. Bacterial and archaeal 16S rRNA and mcrA gene clone libraries were constructed from community DNA preparations. Bacterial clones were affiliated with 13 phyla, of which Firmicutes, Proteobacteria, and Bacteroidetes were represented in all libraries, whereas Actinobacteria, Thermotogae, Lentisphaerae, Acidobacteria, Chloroflexi, Cyanobacteria, Synergistetes, Spirochaetes, Deferribacteres, and Deinococcus-Thermus were exclusively identified in a single library. Within the Archaea domain, the Euryarchaeota phylum was the only one represented. Corresponding sequences were associated with the following orders of hydrogenotrophic methanogens: Methanomicrobiales (Methanoculleus genus) and Methanobacteriales (Methanosphaera and Methanobacterium genera). One archaeal clone was not affiliated with any order and may represent a novel taxon. Diversity indices showed greater diversity of Bacteria when compared to methanogenic Archaea.  相似文献   
878.
Trehalose-6-phosphate (T6P), an intermediate in the trehalose biosynthesis pathway, is emerging as an important regulator of plant metabolism and development. T6P levels are potentially modulated by a group of trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) homologues. In this study, we have isolated 11 TPS genes encoding proteins with both TPS and TPP domains, from rice. Functional complement assays performed in yeast tps1 and tps2 mutants, revealed that only OsTPS1 encodes an active TPS enzyme and no OsTPS protein possesses TPP activity. By using a yeast two-hybrid analysis, a complicated interaction network occurred among OsTPS proteins, and the TPS domain might be essential for this interaction to occur. The interaction between OsTPS1 and OsTPS8 in vivo was confirmed by bimolecular fluorescence complementation and coimmunoprecipitation assays. Furthermore, our gel filtration assay showed that there may exist two forms of OsTPS1 (OsTPS1a and OsTPS1b) with different elution profiles in rice. OsTPS1b was particularly cofractionated with OsTPS5 and OsTPS8 in the 360 kDa complex, while OsTPS1a was predominantly incorporated into the complexes larger than 360 kDa. Collectively, these results suggest that OsTPS family members may form trehalose-6-phosphate synthase complexes and therefore potentially modify T6P levels to regulate plant development.  相似文献   
879.
Single nucleotide polymorphisms (SNPs) are indispensable in such applications as association mapping and construction of high-density genetic maps. These applications usually require genotyping of thousands of SNPs in a large number of individuals. Although a number of SNP genotyping assays are available, most of them are designed for SNP genotyping in diploid individuals. Here, we demonstrate that the Illumina GoldenGate assay could be used for SNP genotyping of homozygous tetraploid and hexaploid wheat lines. Genotyping reactions could be carried out directly on genomic DNA without the necessity of preliminary PCR amplification. A total of 53 tetraploid and 38 hexaploid homozygous wheat lines were genotyped at 96 SNP loci. The genotyping error rate estimated after removal of low-quality data was 0 and 1% for tetraploid and hexaploid wheat, respectively. Developed SNP genotyping assays were shown to be useful for genotyping wheat cultivars. This study demonstrated that the GoldenGate assay is a very efficient tool for high-throughput genotyping of polyploid wheat, opening new possibilities for the analysis of genetic variation in wheat and dissection of genetic basis of complex traits using association mapping approach. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
880.
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