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Cell cycle synchronization of embryonic stem cells : Effect of serum deprivation on the differentiation of embryonic bodies in vitro

Research on stem-cell transplantation has indicated that the success of transplantation largely depends on synchronizing donor cells into the G0/G1 phase. In this study, we investigated the profile of embryonic stem (ES) cell synchronization and its effect on the formation of embryonic bodies (EBs) using cell culture with serum deprivation. The D3 cell line of ES cells was used, and parameters suc

Population genomics of parallel evolution in gene expression and gene sequence during ecological adaptation

Natural selection often produces parallel phenotypic changes in response to a similar adaptive challenge. However, the extent to which parallel gene expression differences and genomic divergence underlie parallel phenotypic traits and whether they are decoupled or not remains largely unexplored. We performed a population genomic study of parallel ecological adaptation among replicate ecotype pairs

Early post-embryonic development in Ellipsostrenua (Trilobita, Cambrian, Sweden) and the developmental patterns in Ellipsocephaloidea

This study documents the early post-embryonic developmental stages (protaspides and early meraspides) of the Cambrian trilobite Ellipsostrenua granulosa (Ahlberg, 1984) from the Gärdsjön Formation of Jämtland, Sweden. The early protaspid stage is characterized by a circular outline of the exoskeleton, two pairs of fixigenal spines, a short preglabellar field, a genal swelling, and prominent bacull

Information Dropout Patterns in Restriction Site Associated DNA Phylogenomics and a Comparison with Multilocus Sanger Data in a Species-Rich Moth Genus

A rapid shift from traditional Sanger sequencing-based molecular methods to the phylogenomic approach with large numbers of loci is underway. Among phylogenomic methods, restriction site associated DNA (RAD) sequencing approaches have gained much attention as they enable rapid generation of up to thousands of loci randomly scattered across the genome and are suitable for nonmodel species. RAD data

The effects of embryonic bodies on differentiation of mouse embryonic stem cells to neuronal cells in vitro

This study was directed at assessing the effects of embryonic bodies on differentiation of the embryonic stem cells. The embryonic bodies of different days gained by means of hanging, suspending and hung-suspended were processed by all-trans retinotic acids for 4 days. Then they were detected by immunocytochemistry methods and were measured to detect the fluorescence intensity changes of calcium a

Porträttbruk i Sverige 1840-1865 : En funktions- och interaktionsstudie

Doktorsavhandling framlagd vid Institutionen för Tema, Linköpings universitet 1994. Avhandlingen behandlar produktion och och bruk av porträtt i Sverige under perioden 1840-65, då fotografiska porträtt gradvis introducerades på den svenska marknaden och trängde tillbaka vissa delar av en etablerad porträttmarknad. Detta dynamiska skede granskas med avseende på samspelet mellan beställare och portr

The Glanville fritillary genome retains an ancient karyotype and reveals selective chromosomal fusions in Lepidoptera

Previous studies have reported that chromosome synteny in Lepidoptera has been well conserved, yet the number of haploid chromosomes varies widely from 5 to 223. Here we report the genome (393 Mb) of the Glanville fritillary butterfly (Melitaea cinxia; Nymphalidae), a widely recognized model species in metapopulation biology and eco-evolutionary research, which has the putative ancestral karyotype

The role of phosphatidylinositol 4-phosphate 5-kinase type І alpha (PIP5K1α) and utility of its inhibitor for targeting metastatic cancer

Prostate cancer (PCa) is the most common cause of cancer-related death in men after lung cancer. Annually, more than 9000 new cases are diagnosed in Sweden and 2500 of them die each year. Metastatic prostate cancer can be treated with castration. However, the disease eventually recurs within 2 years in more aggressive form and becomes insensitive to castration which is termed as castration resista

Transcriptome analysis reveals signature of adaptation to landscape fragmentation

We characterize allelic and gene expression variation between populations of the Glanville fritillary butterfly (Melitaea cinxia) from two fragmented and two continuous landscapes in northern Europe. The populations exhibit significant differences in their life history traits, e.g. butterflies from fragmented landscapes have higher flight metabolic rate and dispersal rate in the field, and higher

Draft genome sequence of the male-killing Wolbachia strain wBol1 reveals recent horizontal gene transfers from diverse sources

Background: The endosymbiont Wolbachia pipientis causes diverse and sometimes dramatic phenotypes in its invertebrate hosts. Four Wolbachia strains sequenced to date indicate that the constitution of the genome is dynamic, but these strains are quite divergent and do not allow resolution of genome diversification over shorter time periods. We have sequenced the genome of the strain wBol1-b, found

Influence of the virus LbFV and of Wolbachia in a host-parasitoid interaction.

Symbionts are widespread and might have a substantial effect on the outcome of interactions between species, such as in host-parasitoid systems. Here, we studied the effects of symbionts on the outcome of host-parasitoid interactions in a four-partner system, consisting of the parasitoid wasp Leptopilina boulardi, its two hosts Drosophila melanogaster and D. simulans, the wasp virus LbFV, and the

Microbial glycoside hydrolases for biomass utilization in biofuels applications

Renewable biomass is predicted to have the potential to meet at least a quarter of the world demand for transportation fuel, but to do so both terrestrial lignocellulosic as well as marine algal resources need to be efficiently utilized. In the processes where these biomasses are converted into different types of energy carriers (for example fuel-alcohols e.g. ethanol or butanol) microbial glycosi

Glycoside hydrolases for extraction and modifi cation of polyphenolic antioxidants

Antioxidants are important molecules that are widely used by humans, both as dietary supplements and as additives to different types of products. In this chapter, we review how flavonoids, a class of polyphenolic antioxidants that are often found in glycosylated forms in many natural resources, can be extracted and modifi ed using glycoside hydrolases (GHs). Glycosylation is a fundamental enzymati

Variations in plasmid content during Escherichia coli cultivations detected by on-line flow injection processing

An integrated flow injection process for analysis of intracellular components of microbes has been used to monitor plasmid content in Escherichia coli cultivations inoculated with cells subcultured in the presence or absence of ampicillin. The system allows sampling, sample handling, cell disruption, separation of intracellular components, and analysis in a semi-on-line mode of operation. The time

Deletion of a cytotoxic, N-terminal putative signal peptide results in a significant increase in production yields in Escherichia coli and improved specific activity of Cel12A from Rhodothermus marinus

The thermostable cellulase Cel12A from Rhodothermus marinus was produced at extremely low levels when expressed in Escherichia coli and was cytotoxic to the cells. In addition, severe aggregation occurred when moderately high concentrations of the enzyme were heat-treated at 65°C, the growth optimum of R. marinus. Sequence analysis revealed that the catalytic module of this enzyme is preceded by a

Cloning and sequence of a thermostable multidomain xylanase from the bacterium Rhodothermus marinus

The gene (xyn1) encoding a Rhodothermus marinus xylanase has been cloned and expressed in Escherichia coli. The gene comprises 5 different domains in an unusual combination. The cellulose binding domains (CBDs) encoded by xyn1 are repeated in tandem at the N-terminus and show similarity with the CBD family IV. The xyn1-gene is the first example encoding a CBD family IV in combination with a xylan

Evidence for substrate binding of a recombinant thermostable xylanase originating from Rhodothermus marinus

The xyn1 encoded 5 domain xylanase from the thermophilic bacterium Rhodothermus marinus binds specifically to xylan, β-glucan and amorphous but not crystalline cellulose. Our results show that the binding is mediated by the full length xylanase, but not by the catalytic domain only. Based on similarities concerning both predicted secondary structure and binding specificity found with one cellulose

Enzymatic specificity and hydrolysis pattern of the catalytic domain of the xylanase Xyn1 from Rhodothermus marinus

The catalytic domain of a xylanase from Rhodothermus marinus was produced in Escherichia coli. The catalytic domain belongs to glycosyl hydrolase family 10. The produced protein has a 22-amino acid leader peptide followed by a 411-amino acid truncated xylanase. The molecular mass was 48 kDa and the recombinant xylanase had a pI of 4.9. The pH and temperature optima for activity were determined to