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991.
We investigated the effects of Rho-associated kinase (ROCK) on migration and cytoskeletal organization in primary human osteoblasts and Saos-2 human osteosarcoma cells. Both cell types were exposed to two different ROCK inhibitors, Y-27632 and HA-1077. In the improved motility assay used in the present study, Y-27632 and HA-1077 significantly increased the migration of both osteoblasts and osteosarcoma cells on plastic in a dose-dependent and reversible manner. Fluorescent images showed that cells of both types cultured with Y-27632 or HA-1077 exhibited a stellate appearance, with poor assembly of stress fibers and focal contacts. Western blotting showed that ROCK inhibitors reduced myosin light chain (MLC) phosphorylation within 5 min without affecting overall myosin light-chain protein levels. Inhibition of ROCK activity is thought to enhance the migration of human osteoblasts through reorganization of the actin cytoskeleton and regulation of myosin activity. ROCK inhibitors may be potentially useful as anabolic agents to enhance the biocompatibility of bone and joint prostheses.  相似文献   
992.

Background  

In the past decades the rapid growth of molecular diagnostics (based on either traditional PCR or isothermal amplification technologies) meet the demand for fast and accurate testing. Although isothermal amplification technologies have the advantages of low cost requirements for instruments, the further improvement on sensitivity, speed and robustness is a prerequisite for the applications in rapid pathogen detection, especially at point-of-care diagnostics. Here, we describe and explore several strategies to improve one of the isothermal technologies, helicase-dependent amplification (HDA).  相似文献   
993.
Sexual dimorphism in carnivores can result from, or induce, variations in diet and foraging behaviour between individuals of different sexes. Sex-driven behavioural changes in feeding habits may also result in a reduction in intraspecific competition for resources, avoiding dietary overlap by concentrating on different prey sizes/types. We therefore evaluated the variation in feeding habits of both males and females of an invasive and range expanding southern European carnivore, the Egyptian mongoose (Herpestes ichneumon), through gut content analysis of road or predator-control killed animals. The analysis of 59 gut samples, collected in Portugal, revealed that northwestern populations of mongooses prey mostly upon mammals [especially lagomorphs, percentage of biomass (PB) = 44%], reptiles (PB = 28%) and arthropods (PB = 2% but percentage of occurrence = 35%). However, females seem to focus mainly on reptiles (PB = 51%) and mammals (PB = 38%), whilst males consume mostly mammals (PB = 75%). The results suggest that this variation maybe a result of sexual dimorphism (since some variation is documented in a few Egyptian mongoose’s skull measures, namely condylobasal length and canine diameter), with males shifting their diets to prey from which they can obtain more energy. Females seem to be focused on predating lighter animals, probably females or juveniles, a fact that has important game management implications.  相似文献   
994.
The genus Penicillium is one of the largest and widely distributed fungal genera described to date. As a result, its taxonomic classification and species discrimination within this genus has become complicated. In this study, 52 isolates that belonged to the Penicillum genus and other related genera were characterized using two DNA-based methods: (i) analysis of the nucleotide sequences of internal transcribed spacers in ribosomal DNA and (ii) analysis of DNA fingerprints that were generated by polymerase chain reactions with specific primers for enterobacterial repetitive intergenic consensus (ERIC) and repetitive extragenic palindromic (REP) sequences, and BOX elements. Using both methods, Penicillium species were discriminated from other fungal genera. Furthermore, Penicillium species that include strains which are used as biocontrol agents, such as P. glabrum, P. purpurogenum, and P. oxalicum, could be distinguished from other Penicillium species using these techniques. Based on our findings, we propose that a polyphasic approach that includes analysis of the nucleotide sequences of ribosomal DNA and detecting the presence of highly conserved, repeated nucleotide sequences can be used to determine the genetic relationships between different Penicillium species. Furthermore, we propose that our results can be used as a start point to develop a strategy to monitor the environmental presence of particular strains of Penicillium species when they are used as biocontrol agents.  相似文献   
995.
996.
In this work, five expansin cDNAs (DlExp15) from ‘Shijia’ longan fruit were isolated and characterized. Moreover, the expression profiles of five expansin genes and the effect of naphthalene acetic acid (NAA) and thidiazuron (TDZ) on their expressions were investigated. The results showed that five expansins exhibited different expression patterns during fruit growth and development. DlExp1 was constitutively expressed in the pericarp while the levels of DlExp1 mRNA in the aril were very high at early stage of fruit development, and decreased gradually from 28 to 77 days after anthesis (DAA). DlExp2 and DlExp4 were related to the growth of pericarp, whereas the expression of DlExp2 and DlExp5 in the aril decreased from 28 to 77 DAA. In addition, NAA and TDZ applied at the stage of rapid pericarp (21 DAA) or aril growth (56 DAA) increased the accumulations of DlExp1 and DlExp2 mRNA in the pericarp and aril, while NAA and TDZ had no or little effect on the accumulations of DlExp3, DlExp4 and DlExp5. DlExp1 and DlExp2 also accumulated highly in rapidly growing tissues, such as young stems and leaves. These findings indicated that Exp genes played a different role in longan fruit growth and showed different response to plant growth substances.  相似文献   
997.
Fatty acid (FA) signature analysis is a powerful tool to investigate foraging ecology and food web dynamics in marine ecosystems. However, use of FA signatures to qualitatively or quantitatively infer diets is potentially complicated by effects of nutritional state on lipid metabolism. Estimation of diets using the quantitative fatty acid signature analysis (QFASA) model requires the use of calibration coefficients to account for predator metabolism of individual FAs. We conducted a captive feeding experiment to determine the effects of a 50% reduction in food intake on growth rate and adipose tissue FA signatures of tufted puffin (Fratercula cirrhata) nestlings, a species that routinely experiences food restriction during growth. FA signatures of chicks fed low- and high-calorie diets both exhibited a change in composition in response to the dietary shift with the direction of change in the composition of individual FAs matching the direction of change in the dietary FAs. Despite a growth rate in the restricted nestlings that was 38% of those in the well-fed group, rates of FA turnover were not different between high and low-calorie treatments, and turnover was close to, but not entirely complete, after 27 days on both high-calorie and restricted diets. FA signatures of tufted puffin nestlings were significantly affected by caloric restriction, but these effects were much less pronounced than those of dietary turnover, and calibration coefficients of puffins fed low and high-calorie diets were highly correlated. Our results demonstrate that changes in physiological state can affect FA metabolism, but future research is required to better understand whether the size of these effects is sufficient to substantially alter diet estimation using the QFASA model.  相似文献   
998.
Microsatellites (SSR--simple sequence repeats, STR--short tandem repeats, SSLP--simple sequence length polymorphism, VNTR--variable number of tandem repeats) are the class of repetitive DNA sequences present in all living organisms. Particular characteristics of microsatellites, such as their presence in the genomes of all living organisms, high level of allelic variation, co-dominant mode of inheritance and potential for automated analysis make them an excellent tool for a number of approaches like genotyping, mapping and positional cloning of genes. The three most popular types of markers containing microsatellite sequences that are presently used are: (1) SSR (simple sequence repeats), generated by amplifying in a PCR reaction with the use of primers complementary to flanking regions; (2) ISSR (inter-simple sequence repeats), based on the amplification of regions between inversely oriented closely spaced microsatellites; and (3) SAMPL (selective amplification of microsatellite polymorphic loci), which utilises AFLP (amplified fragment-length polymorphism) methodology, with one exception--for the second amplification, one of the starters is complementary to the microsatellite sequence. The usefulness of the three above-mentioned markers for numerous purposes has been well documented for plants.  相似文献   
999.
Members of the Argonaute (Ago) protein family associate with small RNAs and have important roles in RNA silencing. Here, we analysed Ago1- and Ago2-containing protein complexes in human cells. Separation of Ago-associated messenger ribonucleoproteins (mRNPs) showed that Ago1 and Ago2 reside in three complexes with distinct Dicer and RNA-induced silencing complex activities. A comprehensive proteomic analysis of Ago-containing mRNPs identified a large number of proteins involved in RNA metabolism. By using co-immunoprecipitation experiments followed by RNase treatment, we biochemically mapped interactions within Ago mRNPs. Using reporter assays and knockdown experiments, we showed that the putative RNA-binding protein RBM4 is required for microRNA-guided gene regulation.  相似文献   
1000.
With the ultimate aim of developing bioremediation technology that use the optimum bacterial community for each pollutant, we performed polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) and phylogenetic analysis and identified communities of culturable bacteria in HgCl(2)- and trichloroethylene (TCE)-contaminated soil microcosms. PCR-DGGE band patterns were similar at 0 and 1 ppm HgCl(2), but changes in specific bands occurred at 10 ppm HgCl(2). Band patterns appearing at 10 and 100 ppm TCE were very different from those at 0 ppm. Phylogenetic analysis showed four bacterial groups in the HgCl(2)-contaminatied cultures: Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes. Most high-density bands, decreased-density bands, and common bands were classified into the phyla Proteobacteria, Actinobacteria, and Firmicutes, respectively; the effects of HgCl(2) on culturable bacteria appeared to differ among phyla. Duganella violaceinigra [98.4% similarity to DNA Data Bank of Japan (DDBJ) strain], Lysobacter koreensis (98.2%), and Bacillus panaciterrae (98.6%) were identified as bacteria specific to HgCl(2)-contaminated soils. Bacteria specific to TCE-contaminated soils were distributed into three phyla (Firmicutes, Proteobacteria, and Actinobacteria), but there was no clear relationship between phylum and TCE effects on culturable bacteria. Paenibacillus kobensis (97.3%), Paenibacillus curdlanolyticus (96.3%), Paenibacillus wynnii (99.8%), and Sphingomonas herbicidovorans (99.4%) were identified as bacteria specific to TCE-contaminated soils. These bacteria may be involved in pollutant degradation.  相似文献   
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