1,959 research outputs found
Abnormal clock gene expression and locomotor activity rhythms in two month-old female APPSwe/PS1dE9 mice
In addition to cognitive decline, Alzheimerās disease (AD) is also characterized by agitation and disruptions in activity and sleep. These symptoms typically occur in the evening or at night and have been referred to as āsundowningā. These symptoms are especially difficult for carers and there are no specific drug treatments. There is increasing evidence that these symptoms reflect an underlying pathology of circadian rhythm generation and transmission. We investigated whether a transgenic mouse model relevant to AD (APPswe/PS1dE9) exhibits circadian alterations in locomotor activity and expression of clock genes involved in the regulation of the circadian cycle. Female mice at 2 months of age were investigated in their home cage. Results show that the APPswe/PS1dE9 transgene alters levels and patterns in circadian rhythm of locomotor activity. Expression of the clock genes Per1, Per2, Cry1 and Cry2 was found to increase at night compared to day in wild-type control mice in the medulla/pons. This effect was blunted for Cry1 and Cry2 gene expression in APPswe/PS1dE9. In summary, this study suggests altered circadian regulation of locomotor activity is abnormal in female APPswe/PS1dE9 mice and that this alteration has biomolecular analogies in a widely available model of AD. Furthermore, the early age at which these effects are manifest suggests that these circadian effects may precede plaque development. The APPswe/PS1dE9 mouse genetic model may have potential to serve as a tool in understanding the neuropathology of circadian abnormalities in AD and as a model system to test novel therapeutic agents for these symptoms
Quantitative Analysis of the Fate of Gold Nanocages In Vitro and In Vivo after Uptake by U87-MG Tumor Cells
Not always equal: When a mother cell that contains Au nanocages divides, the nanoparticles are unequally distributed between the two daughter cells. This unequal distribution of nanoparticles as well as their clearance from the cells (see picture) is quantitatively analyzed both inā
vitro and inā
vivo using two-photon microscopy and photoacoustic microscopy, respectively
Characterization of polyoxometalate I as an inhibitor of RNA-dependent RNA polymerase of Foot and Mouth Disease virus [abstract]
Abstract only availableFoot and Mouth Disease (FMD) is a highly contagious disease that affects a variety of domesticated cloven-hoofed animals including cattle, swine, sheep and goats, as well as several wild animal species. FMD outbreaks are currently controlled with mass-extermination of livestock. The financial cost of potential outbreaks would be immense. This disease is caused by foot-and-mouth disease virus (FMDV), a non-enveloped, single-stranded, positive-sense RNA virus. The purpose of our investigation is to identify chemicals that interfere with the replication of FMDV. As part of this effort we have identified a polyoxometalate inhibitor (polyoxometalate I). We have cloned, expressed and purified FMDV RdRp. We use steady-state kinetic experiments and polymerization assays to characterize the inhibitory activity of the polyoxometalate I, determining the precise inhibitory potential and the mechanism of inhibition. Preliminary results show that polyoxometalate I inhibits the FMDV RdRp surprisingly efficiently with an IC50 of 0.5uM. Current experiments are focusing on a detailed kinetic characterization of the mechanism of action for this inhibitor. This research may provide insights that lead to new treatment options to prevent the further spread of FMD to unaffected animals.USD
TransductionāSpecific ATLAS Reveals a Cohort of Highly Active L 1 Retrotransposons in Human Populations
L ong IN terspersed E lementā1 ( LINE ā1 or L 1) retrotransposons are the only autonomously active transposable elements in the human genome. The average human genome contains ā¼80ā100 active L1s, but only a subset of these L1s are highly active or āhotā. Human L1s are closely related in sequence, making it difficult to decipher progenitor/offspring relationships using traditional phylogenetic methods. However, L1 m RNA s can sometimes bypass their own polyadenylation signal and instead utilize fortuitous polyadenylation signals in 3ā² flanking genomic DNA . Retrotransposition of the resultant m RNA s then results in lineage specific sequence ātagsā (i.e., 3ā² transductions) that mark the descendants of active L1 progenitors. Here, we developed a method (TransductionāSpecific Amplification Typing of L1 Active Subfamilies or TS ā ATLAS ) that exploits L1 3ā² transductions to identify active L1 lineages in a genomeāwide context. TS ā ATLAS enabled the characterization of a putative active progenitor of one L1 lineage that includes the disease causing L1 insertion L1 RP , and the identification of new retrotransposition events within two other āhotā L1 lineages. Intriguingly, the analysis of the newly discovered transduction lineage members suggests that L1 polyadenylation, even within a lineage, is highly stochastic. Thus, TS ā ATLAS provides a new tool to explore the dynamics of L1 lineage evolution and retrotransposon biology. Long INterspersed Elementā1 (L1) retrotransposons are the only independently mobile elements in the human genome. We developed TransductionāSpecific Amplification Typing of L1 Active Subfamilies (TSāATLAS), which utilizes L1ātransduced genomic sequences, to identify a subset of highly active L1s genomeāwide. TSāATLAS enabled the characterization of the putative progenitor of an active diseaseācausing L1 lineage, and identified new retrotransposition events within two other āhotā L1 lineages.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98809/1/humu22327.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/98809/2/humu22327-sup-0001-si.pd
LINE-1 Retrotransposition Activity in Human Genomes
SummaryHighly active (i.e., āhotā) long interspersed element-1 (LINE-1 or L1) sequences comprise the bulk of retrotransposition activity in the human genome; however, the abundance of hot L1s in the human population remains largely unexplored. Here, we used a fosmid-based, paired-end DNA sequencing strategy to identify 68 full-length L1s that are differentially present among individuals but are absent from the human genome reference sequence. The majority of these L1s were highly active in a cultured cell retrotransposition assay. Genotyping 26 elements revealed that two L1s are only found in Africa and that two more are absent from the H952 subset of the Human Genome Diversity Panel. Therefore, these results suggest that hot L1s are more abundant in the human population than previously appreciated, and that ongoing L1 retrotransposition continues to be a major source of interindividual genetic variation
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A Comparison of Tourism-Related Stressors Experienced by Residents of Three Island Destinations
Residents of island tourism destinations are subject to a variety of impacts their quality of life. One impact that has recently emerged as an issue is psychological stress. Psychological stress can often lead to negative physical and mental health outcomes. Island destinations develop along Butlerās (1980) Tourism Area Life Cycle in different ways based on geography, population, accessibility, and a variety of other variables. Oftentimes rapid development follows the creation of transportation links like a new airport or cruise port. The development of cruise ports in particular often bring rapid development with unforeseen consequences. In this study, we examine the tourism related stressors experienced by residents of three island destinations with varying levels of development and cruise tourism visitation. Thematic analysis of residentsā perceived stressors revealed that level of development and type of tourism play a role in the breadth, depth, and type of stressors perceived by residents
Reply to Lipworth et al.
We thank Dr. Lipworth and colleagues for their interest in our work published recently in the Journal (1). They rightly point out that the biology of asthma attacks is more complex than blood eosinophils alone and that corticosteroids have a wide range of other potentially relevant antiinflammatory effects. However, local treatment with inhaled corticosteroids (ICS) is usually the mainstay of patients with frequent eosinophilic exacerbations, and therefore in the great majority of patients, the key question is what oral corticosteroids (OCS) add to ICS in an acute attack (2) and whether this effect is seen with benralizumab. We suggest that depletion of circulating eosinophils is the only effect OCS are likely to have that are not shared with ICS (3)
Fermented Goatās Milk Consumption Improves Duodenal Expression of Iron Homeostasis Genes during Anemia Recovery
Despite the crucial roles of duodenal cytochrome b (Dcytb), divalent metal transporter 1 (DMT1), ferritin light chain (Ftl1), ferroportin 1 (FPN1), transferrin receptor 1 (TfR1), and hepcidin antimicrobial peptide (Hamp) in Fe metabolism, no studies have investigated the modulations of these genes during Fe repletion with fermented milks. Analysis included Fe status markers and gene and protein expression in enterocytes of control and anemic animals fed fermented milks. Fermented goatās milk up-regulated enterocyte Dcytb, DMT1, FPN1, and Ftl1 and down-regulated TfR1 and Hamp gene expression in control and anemic animals. Anemia decreased Dcytb, DMT1, and Ftl1 in animals fed fermented cowās milk and up-regulated TfR1 and Hamp expression. Fe overload down-regulated Dcytb and TfR1 in animals fed fermented cowās milk and up-regulated DMT1 and FPN1 gene expression. Fermented goatās milk increased expression of duodenal Dcytb, DMT1, and FPN1 and decreased Hamp and TfR1, improving Fe metabolism during anemia recovery
Intensified and protective CD4+ T cell immunity in mice with antiādendritic cell HIV gag fusion antibody vaccine
Current human immunodeficiency virus (HIV) vaccine approaches emphasize prime boost strategies comprising multiple doses of DNA vaccine and recombinant viral vectors. We are developing a protein-based approach that directly harnesses principles for generating T cell immunity. Vaccine is delivered to maturing dendritic cells in lymphoid tissue by engineering protein antigen into an antibody to DEC-205, a receptor for antigen presentation. Here we characterize the CD4+ T cell immune response to HIV gag and compare efficacy with other vaccine strategies in a single dose. DEC-205ātargeted HIV gag p24 or p41 induces stronger CD4+ T cell immunity relative to high doses of gag protein, HIV gag plasmid DNA, or recombinant adenovirus-gag. High frequencies of interferon (IFN)-Ī³ā and interleukin 2āproducing CD4+ T cells are elicited, including double cytokine-producing cells. In addition, the response is broad because the primed mice respond to an array of peptides in different major histocompatibility complex haplotypes. Long-lived T cell memory is observed. After subcutaneous vaccination, CD4+ and IFN-Ī³ādependent protection develops to a challenge with recombinant vaccinia-gag virus at a mucosal surface, the airway. We suggest that a DEC-targeted vaccine, in part because of an unusually strong and protective CD4+ T cell response, will improve vaccine efficacy as a stand-alone approach or with other modalities
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