274 research outputs found
Barbara Hurd, 25th Annual ODU Literary Festival
No full textBarbara Hurd is author of Stirring the Mud: On Swamps, Bogs and Human Imagination, Objects in this Mirror, and the forthcoming Three Sources of Light. Her essays and poems have appeared in numerous journals including Best American Essays 1999, Best American Essays 2001, The Yale Review, The Georgia Review, Orion, Nimrod, Prairie Schooner, New Letters, Audubon, Painted Bride Quarterly, and Heliotrope. Hurd is the Wilson H. Elkins Professor at Frostburg State University in Maryland, where she teaches creative writing and co-edits Nightsun
Functional analysis of RP2 and ARL3 in X-linked retinitis pigmentosa
No full textRetinitis Pigmentosa (RP) is a disease of the retina, which causes progressive retinal
degeneration. X-linked RP is one of the most severe subtypes with an estimated 15%
of cases caused by mutations in RP2. RP2 functions as a GTPase Activating Protein
(GAP) for the small G protein ARL3, which is proposed to regulate the traffic of lipid-modified
proteins within photoreceptors. It is hypothesised that mutations in RP2
result in dysregulation of ARL3 and therefore protein mis-trafficking. In order to
elucidate the contribution of ARL3 dysregulation to the pathogenesis of RP, I have
established new mouse models by CRISPR-mediated genome editing. These include
an Rp2h knockout line and a line, which harbours a human pathogenic missense
mutation, E135G, which abolishes interaction with ARL3.
Furthermore, I have generated mice carrying a Q71L missense mutation in Arl3. This
mutation locks ARL3 in the active GTP-bound state, and hence is predicted to
phenocopy Rp2h knockout. Histological examination has revealed that Rp2h
knockout, Rp2h E135G and Arl3 Q71L/+ mutant animals display progressive retinal
degeneration evident from age 6 months. Arl3 Q71L/Q71L animals display retinal
degeneration at age 3 months demonstrating that elevated levels of ARL3-GTP is a
driver of retinal degeneration in mice. Immunofluorescence analysis has shown ARL3
Q71L mice, Rp2h knockout mice and Rp2h E135G/Y mice show mislocalisation of
lipid modified proteins likely driving retinal degeneration, however further analysis has
shown that these mice do not completely phenocopy each other suggesting that levels
of ARL3-GTP may not be the only mechanism contributing to retinal degeneration in
Rp2h mutant mice.
The mechanisms of RP2 regulation are not well understood; therefore to identify
potential interactors of RP2 a BIO-ID proximity labelling assay in RPE-1 cells was
performed. A top hit from this assay was palmitoyltransferase ZDHHC5. I confirmed
this interaction in cells and using a click chemistry based approach demonstrated that
it is unlikely that this enzyme functions to palmitoylate RP2. Using
immunofluorescence in HeLa cells I have shown that overexpression of ZDHHC5 can
rescue the localisation of human pathogenic RP2 mutants C3S and G2A, which are
normally mislocalised in vivo, independent of its catalytic activity. SiRNA knockdown
of ZDHHC5 in cells leads to mislocalisation of RP2 demonstrating ZDHHC5 has a role
in trafficking RP2. Results from these studies have provided new knowledge
regarding the mechanisms that cause retinal degeneration and new insights into the
potential mechanisms that regulate the trafficking of lipid-modified proteins in
photoreceptors
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The Early Letters of Bishop Richard Hurd, 1739 to 1762
No full textRichard Hurd is best known to ecclesiastical historians as one of George III's favourite bishops who was offered, and declined, the archbishopric of Canterbury. These letters, therefore, illuminate the early career of one of the most prominent clerics of the late eighteenth century. The letters begin in 1739, just after Hurd had graduated B.A. at Emmanuel College, Cambridge. They chart his gradual climb up the ladder of ecclesiastical preferment, through his time as Fellow at Emmanuel and end with him settled in the comfortable country rectory of Thurcaston in Leicestershire. Hurd had a wide circle of correspondents. He became a close friend of William Warburton, Bishop of Gloucester, perhaps the most prominent controverialist of the period. He was also a member of a literary circle which included the poets Thomas Gray and William Mason. Indeed, Hurd himself is well-known to students of English literature as the author of Letters on Chivalry and Romance and as a significant figure among the so-called `pre-romantics'. Hurd's letters reveal the full range of his interests, from theology and university politics, through literature, to painting and sculpture. This edition, therefore, not only tells us about Hurd's early life and career, but also provides a valuable insight into the social life of the Anglican clergy in the eighteenth century
Molecular mechanisms underlying Retinitis pigmentosa type 2
No full textThe term “Retinitis pigmentosa” (RP) represents a group of inherited, late-onset
diseases characterised by progressive retinal degeneration due to photoreceptor
death. Mutations in the RP2 gene are found in 7-18% of patients with X-linked RP,
one of the most severe forms. The RP2 gene product is a membrane-associated
protein which encompasses two distinct domains. The N-terminal domain is well
characterised as possessing GTPase-activating protein (GAP) activity towards the
small GTPase ARL3 and thus regulate the transport of lipid-modified proteins within
the photoreceptor cell. However, it is not known if the loss of this particular function
of RP2 is the sole reason that causes the disease, while the role of the protein’s C-terminus
remains unknown. This thesis focuses on the characterisation of two novel
protein-protein interactions of RP2 with the aim to investigate novel roles of the
protein. Firstly, evidence is provided that a highly-conserved cluster of RP2 residues
that span both the N- and C-terminus participate in direct interaction with Osteoclast-stimulating
factor 1 (OSTF1). Two hypotheses are explored about the potential role
of the complex in SRC-mediated RP2 phosphorylation and the regulation of cell
motility. Secondly, the catalytic subunit of DNA-dependent protein kinase (DNA
PK) is identified as a novel interaction partner of RP2 in cultured cells. The two
proteins are shown to co-localise in the nuclear and membrane compartments of a
retinal-derived cell line and might engage in a kinase-substrate relationship. So far,
no evidence was found that RP2 participates in the canonical function of DNA PK
which is the regulation of DNA double-stranded breaks. Finally, the CRISPR/Cas9
genome editing method was applied on zebrafish embryos to generate a novel
vertebrate animal model for the loss of RP2 function. One out of three different
zebrafish lines with rp2 mutations was shown by histology to have mild late-onset
thinning of the photoreceptor outer segments. The present thesis reports previously
unexplored aspects of RP2’s function and will, therefore, contribute to understanding
the molecular mechanisms that underlie RP. Moreover, this thesis will contribute to
the discussion about the usefulness of zebrafish as an RP model
Retinitis Pigmentosa GTPase Regulator (RPGR) protein isoforms in mammalian retina:insights into X-linked Retinitis Pigmentosa and associated ciliopathies
No full textMutations in the cilia-centrosomal protein Retinitis Pigmentosa GTPase Regulator (RPGR) are a frequent cause of retinal degeneration. The RPGR gene undergoes complex alternative splicing and encodes multiple protein isoforms. To elucidate the function of major RPGR isoforms (RPGR 1-19 and RPGR ORF15), we have generated isoform-specific antibodies and examined their expression and localization in the retina. Using sucrose-gradient centrifugation, immunofluorescence and co-immunoprecipitation methods, we show that RPGR isoforms localize to distinct sub-cellular compartments in mammalian photoreceptors and associate with a number of cilia-centrosomal proteins. The RCC1-like domain of RPGR, which is present in all major RPGR isoforms, is sufficient to target it to the cilia and centrosomes in cultured cells. Our findings indicate that multiple isotypes of RPGR may perform overlapping yet somewhat distinct transport-related functions in photoreceptors
Tide Gauge Records, Hurd Point 1996
No full textProgress Code: completedStatement: These data have at least been partially cleaned up as part of a reorganisation of tide gauge data at the Australian Antarctic Division. See the download file for more information. Note, little information is available about this tide gauge.Tide gauge data collected from pressure tide gauge at Hurd Point, Macquarie Island. Data were collected between 1996-03-07 and 1996-10-27.<br/><br/>A temporary tide gauge was installed at Hurd Point as it was suspected that there was a 6 minute wave around the island.<br/>The installation was made to determine whether this is correct.<br/> <br/>Photo<br/>Oblique aerial photos showing location of tide gauge, bench mark AUS188 and Hurd Point trig and photo mof GPS set up.<br/>Gravity meter set up adjacent tide gauge Temporary Bench Mark<br/><br/>Survey<br/><br/>Scans of survey field notes showing location of tide gauge in relation to Hurd Point huts, AUS188 and old Auroral Camera stand,<br/>vertical differences between AUS188, tide gauge temporary mark and tide gauge housing
Investigating the role of eef1a2 in zebrafish as a potential disease model
No full textEukaryotic elongation factor (eEF1A) plays a vital role in protein synthesis. It recruits
amino-acylated tRNAs and delivers them to the ribosome during protein translation.
eEF1A is conserved throughout evolution and exists as independently encoded
isoforms in many species. In mammals, there are two isoforms: eEF1A1 and eEF1A2.
Unlike eEF1A1 which is widely expressed, expression of eEF1A2 is restricted to the
brain, heart and skeletal muscle and is upregulated during development. In mice,
homozygote deletion in Eef1a2 gene resulting in the complete loss of function of
eEF1A2 causes severe neurodegeneration, loss of muscle bulk and death by 28 days.
Recently, de novo heterozygous missense mutation in EEF1A2 has been identified in
humans which cause epilepsy, autism and intellectual disability. The main aim of this
project was to investigate the use of zebrafish as a model to better understand the role
of eEF1A2 in neurological disorders. In addition to its many advantages, the zebrafish
has been shown to be an excellent tool for in vivo drug screening. This is an attractive
attribute for our studies as regards developing treatment strategies for these disorders.
Zebrafish possess four eef1a genes: eef1a1l1, eef1a1a, eef1a1b and eef1a2 which
encodes separate highly similar proteins: eEF1A1L1, eEF1A1A, eEF1A1B and
eEF1A2 respectively. The zebrafish eEF1A2 shares a 94% sequence identity with the
mouse and human eEF1A2 at the amino acid level. In this work, characterisation of
zebrafish eEF1A genes was first carried out, as there is currently little information
available. Using conventional reverse transcriptase polymerase chain reaction (RTPCR)
and real time quantitative PCR (qPCR), I analysed the expression pattern of
eef1a genes at different embryonic stages and adult tissues. These genes were
differentially expressed with only eef1a1l1 detected at earlier developmental stages,
followed by eef1a1a and eef1a1b. Similar to mammals, eef1a2 is detected much later
(48 hpf) during development. Co-expression of eef1a mRNA was observed in the adult
tissues analysed except in liver where eef1a2 was not detected. An attempt to knock-in
one of the epilepsy causing variant, G70S into the zebrafish genome using
CRISPR/Cas9 technology was unsuccessful. However, I established two null eef1a2
mutant lines using this technology. Homozygotes from these null lines showed no
obvious phenotype and in contrast to null Eef1a2 mice, they are fertile and viable
through adulthood. No evidence of neurodegeneration was observed. These results
suggest the possibility of compensatory mechanisms activated by the other eef1a genes
to buffer the loss of eef1a2 in the mutants. However, preliminary findings suggest that
eef1a null mutation might cause zebrafish to be susceptible to PTZ-induced seizures.
Results from this work has provided vital information on functional redundancy of
eef1a genes in zebrafish and a foundation for further validation of the zebrafish as a
model system
Genetic analysis of urinary traits in Scottish and Croatian populations and a functional study of Arl15 in the kidneys
No full textMagnesium is the second most abundant bivalent cation in the body and is essential for many cellular processes. Electrolyte imbalance, including changes in magnesium concentration and other clinically relevant electrolyte ratios in the body, can result in dizziness and arrhythmia. If left untreated, this can result in serious illness or even death. Renal magnesium handling plays an important role in maintaining magnesium homeostasis, however the exact biological mechanisms remain unclear.
A recent genome-wide association study (GWAS) identified an association between the ratio of urinary magnesium concentration to creatinine and variants in the ARL15 gene on chromosome 5. I expanded these analyses by performing meta-analyses for 29 urinary traits in 11,617 individuals from Scottish and Croatian populations. This identified additional genes that may be involved in these traits and confirmed that ARL15 is associated with urinary magnesium (uMg) related traits. The SNP with the most significant P value associated with uMg in the meta-analyses, rs35931, lies within an EGR1 transcription factor binding site in an enhancer region of ARL15. Individuals homozygous for the non-reference allele of rs35931 had lower urinary magnesium levels compared to individuals with the homozygous reference allele. Since ARL15 encodes a GTP-binding protein that regulates the magnesium transporter channel TRPM6, and other proteins involved in magnesium homeostasis in physiologically relevant cell lines, the hypothesis was that genetic variation affects the expression of ARL15, which, in turn modulates magnesium transport by regulating magnesium transporters. Functional studies were performed in order to investigate this and to elucidate the role of ARL15 in magnesium homeostasis both in vitro and in vivo. This confirmed that Arl15 interacts with magnesium transporters within the distal convoluted tubule segment of the kidneys. In vitro knockout models of Arl15 established using CRISPR-Cas9 gene editing in a mouse distal convoluted tubule cell-line showed significantly impaired magnesium transport. Furthermore, homozygous deletion of Arl15 is lethal at the organismal level in the mouse, highlighting the crucial role of ARL15 in health and disease
Military Reserve at Queens Town, Niagara
No full textHistoric plan showing proposed alterations to the land located at the west side of the Niagara River. North is oriented to the top. Descriptive text above the title outlines the purpose of this plan: “Plan shewing the Ground reserved for Government at the Landing place on the West side of the Niagara River; and the proposed situation for Wharf, Stores & ca.” Rods and proposed roads are shown as are land boundaries. Some buildings are shown. Various notations about proposed alterations / additions are present.The plan is signed: “Surveryor General’s Office Toronto, Upper Canada 16th April, 1835. (Copy) Henry Lizars (signed) S. P. Hurd S. G.” It is also signed by the author: “Gother Mann Captn. Command Royl. Engineers.”Authorship indicated: Gother Mann, Henry Lizars, Samuel Proundfoot Hurd, and Thomas George William Eaststaff.Scale: No scale shown.Digital reproduction: Library and Archives Canada, National Map Collection: NMC-22752. Original map size 67 x 83 cm. Black and white copy available in the Map, Data and GIS Library at Call Number: G 3464 Q84 1835 M36.Georeferenced and modified by Map, Data and GIS Library, Brock University
Why You Should Be a Law-Abiding Anarchist (Except When You Shouldn\u27t)
No full textIn this Article, Professor Hurd emphasizes that the rationality of following any given rule resides in one\u27s confidence that one is acting on the balance of reasons for action - including the good reasons for following the rule - and not at all in the fact that there is a rule. This means that if there are are weightier reasons to break the rule than to abide by it, all reasons for rule-following considered, the fact that one is breaking a rule is no more significant than would be the breaking of a stick. The author lists some reasons that make clear that the anarchist\u27s fundamental refusal to substitute rules for her own judgment is fully compatible with, and indeed largely dictates, a life that rarely runs amok of the law
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