68 research outputs found
Potential Economic Impacts of the Managed Haying and Grazing Provision of CRP
According to the Executive Order 12866, a qualitative and quantitative assessment for any Federal mandate resulting in annual expenditures of $100 million or more is required. This study determines how many of the approximately 34.5 million acres of CRP land is brought back in economic use, how that use is allocated between grazing and haying, and the economic impact.CRP, land allocation, economic impact, Agricultural and Food Policy, Environmental Economics and Policy, Land Economics/Use, Research and Development/Tech Change/Emerging Technologies,
Human iPSC Tissue-Engineered Cartilage for Disease Modeling of Skeletal Dysplasia-Causing TRPV4 Mutations
Cartilage is essential to joint development and function. However, there is a variety of cartilage diseases, ranging from developmental (e.g., skeletal dysplasias) to degenerative (e.g., arthritis), in which treatments and therapeutics are lacking. For example, specific point mutations in the ion channel transient receptor potential vanilloid 4 (TRPV4) prevent proper joint development, leading to mild brachyolmia and severe, neonatally lethal metatropic dysplasia. Tissue-engineered cartilage offers an opportunity to elucidate the underlying mechanisms of these cartilage diseases for the development of treatments. Human induced pluripotent stem cells (hiPSCs) are an improved cell source option for cartilage tissue engineering given their minimal donor site morbidity, absence of ethical concerns, and extensive proliferation, differentiation, and gene editing capacities. Unfortunately, previously published hiPSC chondrogenesis protocols were time consuming, difficult to reproduce, and resulted in off-target differentiation. Here, we used two methods to enhance hiPSC chondrogenesis using our previously published stepwise chondrogenic differentiation protocol. Next, we used the improved protocol to perform in vitro disease modeling of brachyolmia and metatropic dysplasia resulting from mutations in mechanosensor TRPV4.
To enhance chondrogenesis, we used a CRISPR-Cas9-edited hiPSC cell line with a GFP reporter to determine surface markers co-expressed with early chondrogenic marker and cartilage matrix protein COL2A1. We found that chondroprogenitors that were positive for PDGFRβ, CD146, and CD166 and negative for CD45 had enhanced chondrogenic potential. In fact, sorted chondroprogenitors from the reporter line and an unedited line had significantly improved homogeneity compared to unsorted as determined by single-cell RNA sequencing. Furthermore, the derived chondrocytes synthesized more homogenous and robust matrix proteins and had higher chondrogenic gene expression. In a continued effort to improve the chondrogenesis protocol, we used bulk and single-cell RNA sequencing to determine where the off-target differentiation occurred. We found that Wnt and melanocyte inducing transcription factor (MITF) signaling were driving the two primary off-target populations: neurogenic and melanogenic, respectively. Single-cell RNA sequencing, histology, and quantification of matrix production confirmed pan-Wnt and MITF inhibition during chondrogenesis improved homogeneity of the cells throughout differentiation and increased chondrogenic potential.
Using the findings from these studies, we created an hiPSC chondrogenesis protocol that follows the developmental mesodermal lineage and uses chemically defined medium. We also provide instructions for digesting the chondrogenic tissue to isolate hiPSC-derived chondrocytes at the single cell level. This protocol has applications for a variety of tissue engineering uses including regenerative therapies, gene editing, drug screening, and disease modeling.
In fact, we applied this protocol for disease modeling of TRPV4 mutations that result in skeletal dysplasias. Using CRISPR-Cas9 gene editing technology, we created two hiPSC lines harboring either the brachyolmia-causing V620I substitution or the metatropic dysplasia-causing T89I substitution. The hiPSCs were chondrogenically differentiated and then were treated with BMP4 to stimulate hypertrophic differentiation. We determined that TRPV4 mutations increased basal signaling but decreased sensitivity to chemical agonist GSK1016790A using electrophysiology techniques and confocal imaging. Furthermore, using bulk RNA sequencing, we found the mutations suppressed chondrocyte maturation and hypertrophy, likely preventing endochondral ossification and long bone formation leading to the disease phenotype.
We also used these cell lines to study the effects of the mutations on mechanotransduction. The hiPSC-derived chondrocytes were physiologically loaded in agarose constructs for 3 hours and then sequenced to elucidate the temporal response to loading. We found the mutant TRPV4 increased gene expression in response to loading compared to wildtype. Gene expression patterns indicated increased proliferation in mutant cells, which could prevent chondrocyte hypertrophic differentiation and endochondral ossification.
Overall, we have developed an improved chondrogenic hiPSC protocol. The resulting tissue-engineered cartilage has many uses including in vitro disease modeling of genetic, developmental conditions, as shown here. Our findings provide target genes for future drug development to treat brachyolmia and metatropic dysplasia. Furthermore, we have increased the understanding of TRPV4 function in chondrocytes, which can be applied to cartilage tissue engineering and other cartilage disease studies
Statistics (ABAC)
This Grants Collection for Statistics was created under a Round Ten ALG Textbook Transformation Grant.
Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.
Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1037/thumbnail.jp
College Algebra (ABAC)
This Grants Collection for College Algebra was created under a Round Ten ALG Textbook Transformation Grant.
Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.
Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/mathematics-collections/1036/thumbnail.jp
Ethnography and data re-use: issues of context and hypertext
This paper seeks to open up debate around context and the re-analysis of stored qualitative data. How to ensure that
subsequent users of deposited datasets can appreciate and be guided by the context of the original study? The paper
introduces the idea of hypertext as one way of facilitating this. We discuss how „context‟ might be thought through in
particular relation to ethnography, where it is frequently difficult to distinguish between data and context, and highlight
some of the inherent problems in the notion of archiving ethnographic context. In a discussion focusing in on multimedia,
we draw attention to the different kinds of contextual information that are necessary to interpret data in different media
forms. The paper‟s starting position is that originators of data and re-users have in front of then a qualitatively different
kind of knowledge-base, due to the fact that data and data-records are not the same thing. This doesn‟t rule out re-use but
does imply that quite full and careful kinds of documentation are necessary to try and make it sufficiently rigorous, a
demand which also, however, has to be balanced against the dangers of information overload. These challenges lead us to
question whether the traditional archiving model is the most suitable way of communicating context to re-users; we
present some of our insights from work on hypertext to explore the potential of the hyperlink as a key contextualising
tool
Skeletal dysplasia-causing TRPV4 mutations suppress the hypertrophic differentiation of human iPSC-derived chondrocytes
Mutations in the TRPV4 ion channel can lead to a range of skeletal dysplasias. However, the mechanisms by which TRPV4 mutations lead to distinct disease severity remain unknown. Here, we use CRISPR-Cas9-edited human-induced pluripotent stem cells (hiPSCs) harboring either the mild V620I or lethal T89I mutations to elucidate the differential effects on channel function and chondrogenic differentiation. We found that hiPSC-derived chondrocytes with the V620I mutation exhibited increased basal currents through TRPV4. However, both mutations showed more rapid calcium signaling with a reduced overall magnitude in response to TRPV4 agonist GSK1016790A compared to wildtype (WT). There were no differences in overall cartilaginous matrix production, but the V620I mutation resulted in reduced mechanical properties of cartilage matrix later in chondrogenesis. mRNA sequencing revealed that both mutations up-regulated several anterio
Fine-mapping identifies multiple prostate cancer risk loci at 5p15, one of which associates with TERT expression
Associations between single nucleotide polymorphisms (SNPs) at 5p15 and multiple cancer types have been reported. We have previously shown evidence for a strong association between prostate cancer (PrCa) risk and rs2242652 at 5p15, intronic in the telomerase reverse transcriptase (TERT) gene that encodes TERT. To comprehensively evaluate the association between genetic variation across this region and PrCa, we performed a fine-mapping analysis by genotyping 134 SNPs using a custom Illumina iSelect array or Sequenom MassArray iPlex, followed by imputation of 1094 SNPs in 22 301 PrCa cases and 22 320 controls in The PRACTICAL consortium. Multiple stepwise logistic regression analysis identified four signals in the promoter or intronic regions of TERT that independently associated with PrCa risk. Gene expression analysis of normal prostate tissue showed evidence that SNPs within one of these regions also associated with TERT expression, providing a potential mechanism for predisposition to disease
The 2014 BFA Graduating Class Department of Visual Arts
Congratulations on the opening of this, your graduate
exhibition. Your presence in this catalogue not only celebrates your achievements while you’ve been with us, but also serves to signal your transition to the next chapter of your life and career.
Whatever your goals, whatever your desire in life, it is my hope that your studies with the visual arts program serve you well, that you continue to explore, search, question, and, it is also my hope that you keep making art.
The Division of Fine Arts is extremely proud of all its graduates and this catalogue, and your presence in it, will serve as a reminder over the years that you were here, and that you made a contribution and a difference to the visual arts program.
All the very best and please keep in touch
Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans
Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio
Evidence that breast cancer risk at the 2q35 locus is mediated through IGFBP5 regulation.
GWAS have identified a breast cancer susceptibility locus on 2q35. Here we report the fine mapping of this locus using data from 101,943 subjects from 50 case-control studies. We genotype 276 SNPs using the 'iCOGS' genotyping array and impute genotypes for a further 1,284 using 1000 Genomes Project data. All but two, strongly correlated SNPs (rs4442975 G/T and rs6721996 G/A) are excluded as candidate causal variants at odds against >100:1. The best functional candidate, rs4442975, is associated with oestrogen receptor positive (ER+) disease with an odds ratio (OR) in Europeans of 0.85 (95% confidence interval=0.84-0.87; P=1.7 × 10(-43)) per t-allele. This SNP flanks a transcriptional enhancer that physically interacts with the promoter of IGFBP5 (encoding insulin-like growth factor-binding protein 5) and displays allele-specific gene expression, FOXA1 binding and chromatin looping. Evidence suggests that the g-allele confers increased breast cancer susceptibility through relative downregulation of IGFBP5, a gene with known roles in breast cell biology
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