1,721,051 research outputs found
Expression profiling of genes involved in the development and function of skeletal muscles in Ts1Cje mouse model of Down Syndrome
No full textIntroduction: Down syndrome (DS) is caused by trisomy of human chromosome 21 (HSA21). Motor dysfunction due to hypotonia has limited labour productivity and have significant effects on socio-economic status in DS individuals. Ts1Cje, a mouse model of DS that exhibits muscle weakness was employed, to investigate the expression profile of selected trisomic and disomic genes involved in skeletal muscle structure and function. Methods: Quadriceps and triceps were harvested from the Ts1Cje (C57BL/6) postnatal day 60-70 mice and corresponding wild-type littermates. Total RNA extracted from these tissues was subjected for quantitative expression profiling of three trisomic genes (Itsn1, Synj1 and Rcan1) involved in neurotransmission and six disomic genes (Lamc1, Leprel1, Myl6b, Msn, Pgm5 and Tmod1) essential for maintenance of muscle structure and function. Real-time quantitative PCR method was used for the profiling. Results: Differential gene expression in DS is reflected by 1.5-fold or more increase in the level of expression as predicted by the gene dosage imbalance hypothesis. The analysis showed no significant changes in the expression level of trisomic genes (Itsn1, Synj1 and Rcan1). On contrary, disomic genes, Leprel1 and Pgm5, were upregulated for more than 1.5-fold in DS quadriceps whereas Lamc1, Myl6b and Pgm5 were upregulated for more than 1.5 fold in DS triceps as compared to the wild-type group. Conclusions: Our findings suggest that the dysregulation of Lamc1, Leprel1, Myl6b and Pgm5 genes is associated to muscle weakness seen in Ts1Cje and may play a role in molecular pathogenesis of muscle weakness in DS
Introduction : brain science : inside out
Get PDFBRAIN – remains as the most sophisticated organ in the known universe. While more has been learned about it in the past two hundred years, we are still at a very early stage in our understanding. The field of Neuroscience is still in its infancy, but is rapidly exploding – turning many yesterday’s brain “myth” to today’s brain “facts”
smART Brain
Get PDFIn the smART Brain section, visitors can expect a dynamic yet entertaining science journey and educational time. “The Master Hat” is specially designed to portray the left-right brain dominance : the right brain is often regarded as the more creative side whilst the left brain is regarded as the analytical side
Challenges and future perspectives for 3D cerebral organoids as a model for complex brain disorders
Get PDFThe human brain is made up of billions of neurons and glial cells which are interconnected and organized into specific patterns of neural circuitry, and hence is arguably the most sophisticated organ in human, both structurally and functionally. Studying the underlying mechanisms responsible for neurological or neurodegenerative disorders and the developmental basis of complex brain diseases such as autism, schizophrenia, bipolar disorder, Alzheimer’s and Parkinson’s disease has proven challenging due to practical and ethical limitations on experiments with human material and the limitations of existing biological/animal models. Recently, cerebral organoids have been proposed as a promising and revolutionary model for understanding complex brain disorders and preclinical drug screening
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Spatiotemporal regulation of multiple overlapping sense and novel natural antisense transcripts at the Nrgn and Camk2n1 gene loci during mouse cerebral corticogenesis
Get PDFFirst published online: August 6, 2010Nrgn and Camk2n1 are highly expressed in the brain and play an important role in synaptic long-term potentiation via regulation of Ca2+/calmodulin-dependent protein kinase II. We have shown that the gene loci for these 2 proteins are actively transcribed in the adult cerebral cortex and feature multiple overlapping transcripts in both the sense and antisense orientations with alternative polyadenylation. These transcripts were upregulated in the adult compared with embryonic and P1.5 mouse cerebral cortices, and transcripts with different 3′ untranslated region lengths showed differing expression profiles. In situ hybridization (ISH) analysis revealed spatiotemporal regulation of the Nrgn and Camk2n1 sense and natural antisense transcripts (NATs) throughout cerebral corticogenesis. In addition, we also demonstrated that the expression of these transcripts was organ-specific. Both Nrgn and Camk2n1 sense and NATs were also upregulated in differentiating P19 teratocarcinoma cells. RNA fluorescent ISH analysis confirmed the capability of these NATs to form double-stranded RNA aggregates with the sense transcripts in the cytoplasm of cells obtained from the brain. We propose that the differential regulation of multiple sense and novel overlapping NATs at the Nrgn and Camk2n1 loci will increase the diversity of posttranscriptional regulation, resulting in cell- and time-specific regulation of their gene products during cerebral corticogenesis and function.King-Hwa Ling, Chelsee A. Hewitt, Tim Beissbarth, Lavinia Hyde, Pike-See Cheah, Gordon K. Smyth, Seong-Seng Tan, Christopher N. Hahn, Tim Thomas, Paul Q. Thomas and Hamish S. Scot
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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