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Selected Works

2011

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Articles 31 - 60 of 1675

Full-Text Articles in Social and Behavioral Sciences

Fairmount Greenway - A Community Initative, Leah H. Bamberger, Liliana Carvajal, Mary F. Dehais, Yuanfang Gong, John E. Hulsey, Eric C. Kells, Kimberley Klosterman, Pamela Jo Landi, Adam G. Monroy, Seth A. Morrow, Bryan O'Bara, Jie Su, Arianna Thompson, Owen M. White Dec 2011

Fairmount Greenway - A Community Initative, Leah H. Bamberger, Liliana Carvajal, Mary F. Dehais, Yuanfang Gong, John E. Hulsey, Eric C. Kells, Kimberley Klosterman, Pamela Jo Landi, Adam G. Monroy, Seth A. Morrow, Bryan O'Bara, Jie Su, Arianna Thompson, Owen M. White

jie su

This studio was based on the Fairmount Greenway that was developed through a series of public meetings with the neighborhood community and with consultants from the firm Crosby, Schlessinger and Smallridge (CSS). The Fairmount Greenway, while drawing its identity from the traditional greenway model is in fact a reinterpretation of an urban greenway. The greenway path follows along both primary and secondary city streets because of the lack of space along the rail right-of-way. The Fairmount Greenway begins at what will be a new station stop at New Market South Bay near Upham’s Corner in northern Dorchester. The greenway follows …

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From The Quadrangle To The River: Revitalizing The Heart Of Downtown Springfield, Mary F. Dehais, Yuanfang Gong, John E. Hulsey, Pamela Jo Landi, Adam G. Monroy, Seth A. Morrow, Alexander G. Seib, Jie Su, Kate A. Tooke, Owen M. White, Emily S. Wright, Kuang Xin, Xiao Zhou Dec 2011

From The Quadrangle To The River: Revitalizing The Heart Of Downtown Springfield, Mary F. Dehais, Yuanfang Gong, John E. Hulsey, Pamela Jo Landi, Adam G. Monroy, Seth A. Morrow, Alexander G. Seib, Jie Su, Kate A. Tooke, Owen M. White, Emily S. Wright, Kuang Xin, Xiao Zhou

jie su

This studio report explores community service learning in the graduate urban design studio taught in the in Department of Landscape Architecture and Regional Planning at the University of Massachusetts Amherst and instructed by Professor Frank Sleegers. The project will began with a visioning workshop, conducted to engage community members in the shaping of project goals and objectives within the project area of downtown Springfield. These findings were brought to the studio and guided the design process and outcomes. Five design teams developed five alternative master plans for the core area of downtown Springfield with focus on the revitalization of open …

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International Relations Theory And Chinese Philosophy, Rosita Dellios Dec 2011

International Relations Theory And Chinese Philosophy, Rosita Dellios

Rosita Dellios

Extract:Insights drawn from a comparison between International Relations theory and Chinese philosophy provide a timely vantage point for ‘Chinese Engagements’ at this historical juncture of China’s emergence as a twenty-first century global power. In this chapter, after a brief historical background, three major International Relations theoretical perspectives are examined: neorealism, neoliberal institutionalism, and social constructivism. In addition, hegemonic stability theory and global governance are selected as concepts relevant to the globalised political world. The theory of correlativity is discussed as an introduction to Chinese philosophy and this is followed by Daoism, Confucianism and Buddhism as the tripartite philosophical foundations of …

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Inconstitucionalidade Da Abolição De Feriados, Paulo Ferreira Da Cunha Dec 2011

Inconstitucionalidade Da Abolição De Feriados, Paulo Ferreira Da Cunha

Paulo Ferreira da Cunha

Feriados celebrando datas essenciais do Estado ou da República são símbolos nacionais. Como tais, são matéria constitucional (materialmente constitucional) ainda que não constante do texto da Constituição. Abolir feriados destes, para mais sem sequer prévia discussão nacional, além de denotar um desprezo profundo pela cultura e pela História... é inconstitucional.

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Understanding The Legitimacy Of Both Dissension And Acceptance Of Accommodative Monetary Policy, Maximilian Bevan Dec 2011

Understanding The Legitimacy Of Both Dissension And Acceptance Of Accommodative Monetary Policy, Maximilian Bevan

Maximilian Bevan

No abstract provided.

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Patriotic Protest, Racist Revolt, Or Just Another Event: Television News Framing Of The Tea Party Movement, Malaena Taylor Dec 2011

Patriotic Protest, Racist Revolt, Or Just Another Event: Television News Framing Of The Tea Party Movement, Malaena Taylor

Malaena J Taylor

Research on the relationships between mass media and social movements has focused largely on the ways in which newspapers and mainstream television networks represent leftist movements. The conservative, pro-capitalist Tea Party movement, which began to receive national news coverage in February 2009, provides an opportunity to examine the same types of relationships on the other end of the political spectrum, in order to test generalizability of existing models. The Tea Party has received extensive media coverage by 24-hour cable news networks; these networks have not been included in prior studies on media framings of social movements. Using both qualitative and …

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De Keynes Aos Desafios Futuros, Paulo Ferreira Da Cunha Dec 2011

De Keynes Aos Desafios Futuros, Paulo Ferreira Da Cunha

Paulo Ferreira da Cunha

Keynes anda esquecido pelos economistas da moda. É pena, porque o resultado, catastrófico, das políticas neoliberais está à vista. Entretanto, reflecte-se sobre como a velha esquerda moderada se deixou contaminar pelo vírus do neoliberalismo (e a velha direita social também, e mais ainda), havendo porém novas teorias e propostas no horizonte, como o capitalismo humanista, no Brasil e em Espanha, e a "next left", no Reino Unido. Será possível uma confluência coerente e frutuosa dos que não querem, de uns e de outros lados, um mundo só baseado na ganância e na aniquilação do mais fraco? É o grande desafio …

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Massachusetts’ Clean Energy Cluster, David Levy, David Terkla Dec 2011

Massachusetts’ Clean Energy Cluster, David Levy, David Terkla

David G. Terkla

The renewable energy industry in Massachusetts is identified through a “top-down” and “bottom-up” processes to determine the total employment and boundaries of this sector. Related sectors are also identified that are linked to the core renewable energy sector in the state and policies for enhancing this cluster are suggested.

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Older Workers: An Essential Resource For Massachusetts, Peter B. Doeringer, Andrew Sum, David Terkla Dec 2011

Older Workers: An Essential Resource For Massachusetts, Peter B. Doeringer, Andrew Sum, David Terkla

David G. Terkla

The Massachusetts Jobs Council, the Governor’s principal advisory board on workforce development, established the Blue Ribbon Commission on Older Workers in 1997 to analyze the labor market for older workers in the Commonwealth and to recommend policies to improve the economic status of the older labor force. The Commission held numerous hearings, town meetings, and focus groups to solicit the views of older workers, employers, labor organizations, and training professionals, and it reviewed the findings of extensive research on older workers in Massachusetts.

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The Boston Mpo Planning Process And Low-Income Suburban-To-Suburban Transportation Needs, Phillip Granberry, Michael Landon, David Terkla Dec 2011

The Boston Mpo Planning Process And Low-Income Suburban-To-Suburban Transportation Needs, Phillip Granberry, Michael Landon, David Terkla

David G. Terkla

The rapid evolution in the Boston MPO transportation planning process is discussed as well as its particular application to the suburban-suburban transportation needs of low income individuals. The results of two experiments designed to improve access to transportation for low income suburban individuals are discussed and policy suggestions are made for improving such access.

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2010 Massachusetts Recreational Boater Survey: Final Report Submitted To The Massachusetts Ocean Partnership, Dan Hellin, Jack Wiggin, Kristin Uiterwyk, Kim Starbuck, Nicholas Napoli, David Terkla, Chris Watson, Anthony Roman, Leona Roach, Tim Welch Dec 2011

2010 Massachusetts Recreational Boater Survey: Final Report Submitted To The Massachusetts Ocean Partnership, Dan Hellin, Jack Wiggin, Kristin Uiterwyk, Kim Starbuck, Nicholas Napoli, David Terkla, Chris Watson, Anthony Roman, Leona Roach, Tim Welch

David G. Terkla

The Massachusetts Ocean Management Plan (Plan) completed in 2009 recognized recreational boating as an activity with “significant actual and prospective conflicts among multiple waterway uses in Massachusetts” and included the economic value of recreational boating as a key socio-economic indicator that will be used to inform coastal management. At the time of Plan completion, statistically robust recreational boating data were identified as an important need for comprehensive ocean planning. To fill this data gap, the 2010 Massachusetts Recreational Boater Survey gathered information on boating activity in Massachusetts’ coastal and ocean waters directly from recreational boaters. Researchers sent 10,000 surveys to …

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Uncertainty, Technical Change, And Policy Models, Erin Baker, Leon Clarke, Jeffrey Keisler, Ekundayo Shittu Dec 2011

Uncertainty, Technical Change, And Policy Models, Erin Baker, Leon Clarke, Jeffrey Keisler, Ekundayo Shittu

Jeffrey Keisler

Both climate change and technical change are uncertain. In this paper we show the importance of including both uncertainties when modeling for policy analysis. We then develop an approach for incorporating uncertainty of technical change into climate change policy analysis. We define and demonstrate a protocol for bottom-up expert assessments about prospects for technologies. We then describe a method for using such assessments to derive a probability distribution over future abatement curves, and to estimate random return functions for technological investment in different areas. Finally, we show how these analytic results could be used in a variety of energy-economic models …

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Model For Amorphous Aggregation Processes, Samual Stranks, Heath Ecroyd, Steve Van Sluyter, Elizabeth J. Waters, John A. Carver, Lorenz Von Smekal Dec 2011

Model For Amorphous Aggregation Processes, Samual Stranks, Heath Ecroyd, Steve Van Sluyter, Elizabeth J. Waters, John A. Carver, Lorenz Von Smekal

Heath Ecroyd

The amorphous aggregation of proteins is associated with many phenomena, ranging from the formation of protein wine haze to the development of cataract in the eye lens and the precipitation of recombinant proteins during their expression and purification. While much literature exists describing models for linear protein aggregation, such as amyloid fibril formation, there are few reports of models which address amorphous aggregation. Here, we propose a model to describe the amorphous aggregation of proteins which is also more widely applicable to other situations where a similar process occurs, such as in the formation of colloids and nanoclusters. As first …

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Endogenous Redox Activity In Mouse Spermatozoa And Its Role In Regulating The Tyrosine Phosphorylation Events Associated With Sperm Capacitation, Heath W. Ecroyd, Russell C. Jones, Robert J. Aitken Dec 2011

Endogenous Redox Activity In Mouse Spermatozoa And Its Role In Regulating The Tyrosine Phosphorylation Events Associated With Sperm Capacitation, Heath W. Ecroyd, Russell C. Jones, Robert J. Aitken

Heath Ecroyd

We investigated the role of endogenous redox activity in regulating the signal transduction pathway leading to tyrosine phosphorylation in mouse spermatozoa. Endogenous redox activity was monitored using a luminol-peroxidase chemiluminescent probe. Chemiluminescence increased in spermatozoa that were actively undergoing cAMP-mediated tyrosine phosphorylation events associated with capacitation and was inhibited in a dose-dependent manner by addition of catalase or diphenylene iodonium, both of which also inhibited tyrosine phosphorylation within the cell at points downstream of cAMP. Excluding bicarbonate from the incubation medium reduced the redox activity of sperm by 80-90% and dramatically reduced tyrosine phosphorylation. This study provides the first evidence …

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Carboxymethylated-K-Casein: A Convenient Tool For The Identification Of Polyphenolic Inhibitors Of Amyloid Fibril Formation, John A. Carver, Peter J. Duggan, Heath Ecroyd, Yanqin Liu, Adam G. Meyer, C E. Tranberg Dec 2011

Carboxymethylated-K-Casein: A Convenient Tool For The Identification Of Polyphenolic Inhibitors Of Amyloid Fibril Formation, John A. Carver, Peter J. Duggan, Heath Ecroyd, Yanqin Liu, Adam G. Meyer, C E. Tranberg

Heath Ecroyd

Reduced and carboxymethylated-κ-casein (RCM-κ-CN) is a milk-derived amyloidogenic protein that readily undergoes nucleation-dependent aggregation and amyloid fibril formation via a similar pathway to disease-specific amyloidogenic peptides like amyloid beta (Aβ), which is associated with Alzheimer’s disease. In this study, a series of flavonoids, many known to be inhibitors of Aβ fibril formation, were screened for their ability to inhibit RCM-κ-CN fibrilisation, and the results were compared with literature data on Aβ inhibition. Flavonoids that had a high degree of hydroxylation and molecular planarity gave good inhibition of RCM-κ-CN fibril formation. IC50 values were between 10- and 200-fold higher with RCM-κ-CN …

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An Epididymal Form Of Cauxin, A Carboxylesterase-Like Enzyme, Is Present And Active In Mammalian Male Reproductive Fluids, Heath W. Ecroyd, Maya Belghazi, Jl Dacheux, M Miyazaki, T Yamashita, Jl Gatti Dec 2011

An Epididymal Form Of Cauxin, A Carboxylesterase-Like Enzyme, Is Present And Active In Mammalian Male Reproductive Fluids, Heath W. Ecroyd, Maya Belghazi, Jl Dacheux, M Miyazaki, T Yamashita, Jl Gatti

Heath Ecroyd

Mass spectrometric analysis of a prion protein (PrP)-containing complex isolated from ram cauda epididymal fluid revealed a protein that showed homology to a carboxylesterase-like protein previously identified in cat urine (cauxin). Using anticauxin antibodies, immunoreactive bands were detected in corpus and cauda epididymal fluid from all mammals tested (ram, boar, mouse, and cat). In the ram, the protein was also present in seminal fluid but not found to be associated with sperm. The bands reacting with the anti-cauxin antibody coincided with those having esterase activity in a zymographic assay and its levels paralleled the esterase activity of native epididymal fluids. …

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The Dissociated Form Of Kappa-Casein Is The Precursor To Its Amyloid Fibril Formation, Heath Ecroyd, David Thorn, Yanqin Liu, John Carver Dec 2011

The Dissociated Form Of Kappa-Casein Is The Precursor To Its Amyloid Fibril Formation, Heath Ecroyd, David Thorn, Yanqin Liu, John Carver

Heath Ecroyd

Bovine milk kappa-casein forms a self-associating oligomeric micelle-like species, in equilibrium with dissociated forms. In its native form, intra- and inter-molecular disulfide bonds lead to the formation of multimeric species ranging from monomers to decamers. When incubated under conditions of physiological pH and temperature, both reduced and non-reduced kappa-casein form highly structured beta-sheet amyloid fibrils. We investigated whether the precursor to kappa-casein fibril formation is a dissociated state of the protein or its oligomeric micelle-like form. We show that reduced kappa-casein is capable of forming fibrils well below its critical micelle concentration, i.e. at concentrations where only dissociated forms of …

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The Interaction Of Unfolding Α-Lactalbumin And Malate Dehydrogenase With The Molecular Chaperone Αb-Crystallin: A Light And X-Ray Scattering Investigation, J W. Regini, Heath Ecroyd, Sarah Meehan, Kristen Bremmell, Matthew J. Clarke, Donna Lammie, Tim Wess, John A. Carver Dec 2011

The Interaction Of Unfolding Α-Lactalbumin And Malate Dehydrogenase With The Molecular Chaperone Αb-Crystallin: A Light And X-Ray Scattering Investigation, J W. Regini, Heath Ecroyd, Sarah Meehan, Kristen Bremmell, Matthew J. Clarke, Donna Lammie, Tim Wess, John A. Carver

Heath Ecroyd

Purpose: The molecular chaperone αB-crystallin is found in high concentrations in the lens and is present in all major body tissues. Its structure and the mechanism by which it protects its target protein from aggregating and precipitating are not known. Methods: Dynamic light scattering and X-ray solution scattering techniques were used to investigate structural features of the αB-crystallin oligomer when complexed with target proteins under mild stress conditions, i.e., reduction of α- lactalbumin at 37 °C and malate dehydrogenase when heated at 42 °C. In this investigation, the size, shape and particle distribution of the complexes were determined in real-time …

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(-)-Epigallocatechin-3-Gallate (Egcg) Maintains K-Casein In Its Pre-Fibrillar State Without Redirecting Its Aggregation Pathway, Sean A. Hudson, Heath Ecroyd, Francis C. Dehle, Ian F. Musgrave, John Carver Dec 2011

(-)-Epigallocatechin-3-Gallate (Egcg) Maintains K-Casein In Its Pre-Fibrillar State Without Redirecting Its Aggregation Pathway, Sean A. Hudson, Heath Ecroyd, Francis C. Dehle, Ian F. Musgrave, John Carver

Heath Ecroyd

The polyphenol (-)-epigallocatechin-3-gallate (EGCG) has recently attracted much research interest in the field of protein-misfolding diseases because of its potent anti-amyloid activity against amyloid-beta, alpha-synuclein and huntingtin, the amyloid-fibril-forming proteins involved in Alzheimer's, Parkinson's and Huntington's diseases, respectively. EGCG redirects the aggregation of these polypeptides to a disordered off-folding pathway that results in the formation of non-toxic amorphous aggregates. whether this anti-fibril activity is specific to these disease-related target proteins or ismore generic remains to be established. In addition, the mechanism by which EGCG exerts its effects, as with all anti-amyloidogenic polyphenols, remains unclear. To address these aspects, we have …

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New Proteins Identified In Epididymal Fluid From The Platypus (Ornithorhynchus Anatinus), Jean-Louis Dacheux, Francoise Dacheux, Valerie Labas, Heath Ecroyd, Brett Nixon, Russell C. Jones Dec 2011

New Proteins Identified In Epididymal Fluid From The Platypus (Ornithorhynchus Anatinus), Jean-Louis Dacheux, Francoise Dacheux, Valerie Labas, Heath Ecroyd, Brett Nixon, Russell C. Jones

Heath Ecroyd

The platypus epididymal proteome is being studied because epididymal proteins are essential for male fertility in mammals and it is considered that knowledge of the epididymal proteome in an early mammal would be informative in assessing the convergence and divergence of proteins that are important in the function of the mammalian epididymis. Few of the epididymal proteins that have been identified in eutherian mammals were found in platypus caudal epididymal fluid, and the major epididymal proteins in the platypus (PXN-FBPL, SPARC and E-OR20) have never been identified in the epididymis of any other mammal.

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Mimicking Phosphorylation Of Alphab-Crystallin Affects Its Chaperone Activity, Heath W. Ecroyd, Sarah Meehan, J Horwitz, Andrew Aquilina, J L Benesch, C V Robinson, Cait Macphee, John Carver Dec 2011

Mimicking Phosphorylation Of Alphab-Crystallin Affects Its Chaperone Activity, Heath W. Ecroyd, Sarah Meehan, J Horwitz, Andrew Aquilina, J L Benesch, C V Robinson, Cait Macphee, John Carver

Heath Ecroyd

No abstract provided.

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The Thioflavin T Fluorescence Assay For Amyloid Fibril Detection Can Be Biased By The Presence Of Exogenous Compounds, Sean A. Hudson, Heath Ecroyd, Tak W. Kee, John A. Carver Dec 2011

The Thioflavin T Fluorescence Assay For Amyloid Fibril Detection Can Be Biased By The Presence Of Exogenous Compounds, Sean A. Hudson, Heath Ecroyd, Tak W. Kee, John A. Carver

Heath Ecroyd

Thioflavin T (ThT) dye fluorescence is used regularly to quantify the formation and inhibition of amyloid fibrils in the presence of anti-amyloidogenic compounds such as polyphenols. However, in this study, it was shown, using three polyphenolics (curcumin, quercetin and resveratrol), that ThT fluorescence should be used with caution in the presence of such exogenous compounds. The strong absorptive and fluorescent properties of quercetin and curcumin were found to significantly bias the ThT fluorescence readings in both in situ real-time ThT assays and single time-point dilution ThT-type assays. The presence of curcumin at concentrations as low as 0.01 and 1 uM …

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Unraveling The Mysteries Of Protein Folding And Misfolding, Heath Ecroyd, John A. Carver Dec 2011

Unraveling The Mysteries Of Protein Folding And Misfolding, Heath Ecroyd, John A. Carver

Heath Ecroyd

This mini-review focuses on the processes and consequences of protein folding and misfolding. The latter process often leads to protein aggregation and precipitation with the aggregates adopting either highly ordered (amyloid fibril) or disordered (amorphous) forms. In particular, the amyloid fibril is discussed because this form has gained considerable notoriety due to its close links to a variety of debilitating diseases including Alzheimer's, Parkinson's, Huntington's, and Creutzfeldt-Jakob diseases, and type-II diabetes. In each of these diseases a different protein forms fibrils, yet the fibrils formed have a very similar structure. The mechanism by which fibrils form, fibril structure, and the …

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Crystallin Proteins And Amyloid Fibrils, Heath Ecroyd, John A. Carver Dec 2011

Crystallin Proteins And Amyloid Fibrils, Heath Ecroyd, John A. Carver

Heath Ecroyd

Improper protein folding (misfolding) can lead to the formation of disordered (amorphous) or ordered (amyloid fibril) aggregates. The major lens protein, alpha-crystallin, is a member of the small heat-shock protein (sHsp) family of intracellular molecular chaperone proteins that prevent protein aggregation. Whilst the chaperone activity of sHsps against amorphously aggregating proteins has been well studied, its action against fibril-forming proteins has received less attention despite the presence of sHsps in deposits found in fibril-associated diseases (e.g. Alzheimer's and Parkinson's). In this review, the literature on the interaction of alpha B-crystallin and other sHsps with fibril-forming proteins is summarized. In particular, …

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Alphab-Crystallin Inhibits The Cell Toxicity Associated With Amyloid Fibril Formation By Kappa-Casein And The Amyloid-Beta Peptide, Francis C. Dehle, Heath Ecroyd, Ian F. Musgrave, John A. Carver Dec 2011

Alphab-Crystallin Inhibits The Cell Toxicity Associated With Amyloid Fibril Formation By Kappa-Casein And The Amyloid-Beta Peptide, Francis C. Dehle, Heath Ecroyd, Ian F. Musgrave, John A. Carver

Heath Ecroyd

Amyloid fibril formation is associated with diseases such as Alzheimer’s, Parkinson’s, and prion diseases. Inhibition of amyloid fibril formation by molecular chaperone proteins, such as the small heat-shock protein αB-crystallin, may play a protective role in preventing the toxicity associated with this form of protein misfolding. Reduced and carboxymethylated κ-casein (RCMκ-CN), a protein derived from milk, readily and reproducibly forms fibrils at physiological temperature and pH. We investigated the toxicity of fibril formation by RCMκ-CN using neuronal model PC12 cells and determined whether the inhibition of fibril formation altered its cell toxicity. To resolve ambiguities in the literature, we also …

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The Epididymal Soluble Prion Protein Forms A High-Molecular-Mass Complex In Association With Hydrophobic Proteins, Heath W. Ecroyd, Maya Belghazi, Jean-Louis Dacheux, Jean-Luc Gatti Dec 2011

The Epididymal Soluble Prion Protein Forms A High-Molecular-Mass Complex In Association With Hydrophobic Proteins, Heath W. Ecroyd, Maya Belghazi, Jean-Louis Dacheux, Jean-Luc Gatti

Heath Ecroyd

We have shown previously that a 'soluble' form of PrP (prion protein), not associated with membranous vesicles, exists in the male reproductive fluid [Ecroyd, Sarradin, Dacheux and Gatti (2004) Biol. Reprod. 71, 993-1001]. Attempts to purify this 'soluble' PrP indicated that it behaves like a high-molecular-mass complex of more than 350 kDa and always co-purified with the same set of proteins. The main associated proteins were sequenced by MS and were found to match to clusterin (apolipoprotein J), BPI (bacterial permeability-increasing protein), carboxylesterase-like urinary excreted protein (cauxin), beta-mannosidase and beta-galactosidase. Immunoblotting and enzymatic assay confirmed the presence of clusterin and …

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Compartmentalization Of Prion Isoforms Within The Reproductive Tract Of The Ram, Heath W. Ecroyd, Pierre Sarradin, Jean-Louis Dacheux, Jean-Luc Gatti Dec 2011

Compartmentalization Of Prion Isoforms Within The Reproductive Tract Of The Ram, Heath W. Ecroyd, Pierre Sarradin, Jean-Louis Dacheux, Jean-Luc Gatti

Heath Ecroyd

Cellular prion protein (Prp(C)) is a glycoprotein usually associated with membranes via its glycosylphosphatidylinositol (GPI) anchor. The trans-conformational form of this protein (Prp(SC)) is the suggested agent responsible for transmissible neurodegenerative spongiform encephalopathies. This protein has been shown on sperm and in the reproductive fluids of males. Antibodies directed against the C-terminal sequence near the GPI-anchor site, an N-terminal sequence, and against the whole protein showed that the Prp isoforms were compartmentalized within the reproductive tract of the ram. Immunoblotting with the three antibodies showed that the complete protein and both N- and C-terminally truncated and glycosylated isoforms are present …

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Site-Directed Mutations In The C-Terminal Extension Of Human Αb-Crystallin Affect Chaperone Function And Block Amyloid Fibril Formation, T. M. Treweek, Heath Ecroyd, D. M. Williams, S. Meehan, J. A. Carver, M. J. Walker Dec 2011

Site-Directed Mutations In The C-Terminal Extension Of Human Αb-Crystallin Affect Chaperone Function And Block Amyloid Fibril Formation, T. M. Treweek, Heath Ecroyd, D. M. Williams, S. Meehan, J. A. Carver, M. J. Walker

Heath Ecroyd

Alzheimer’s, Parkinson’s and Creutzfeldt-Jakob disease are associated with inappropriate protein deposition and ordered amyloid fibril assembly. Molecular chaperones, including αBcrystallin, play a role in the prevention of protein deposition. A series of site-directed mutants of the human molecular chaperone, αB-crystallin, were constructed which focused on the flexible C-terminal extension of the protein. We investigated the structural role of this region as well as its role in the chaperone function of αB-crystallin under different types of protein aggregation, i.e. disordered amorphous aggregation and ordered amyloid fibril assembly. It was found that mutation of lysine and glutamic acid residues in the C-terminal …

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Small Heat-Shock Proteins Interact With A Flanking Domain To Suppress Polyglutamine Aggregation, Amy L. Roberston, Stephen J. Headey, Helen M. Saunders, Heath Ecroyd, Martin J. Scanlon, John A. Carver, Stephen P. Bottomley Dec 2011

Small Heat-Shock Proteins Interact With A Flanking Domain To Suppress Polyglutamine Aggregation, Amy L. Roberston, Stephen J. Headey, Helen M. Saunders, Heath Ecroyd, Martin J. Scanlon, John A. Carver, Stephen P. Bottomley

Heath Ecroyd

Small heat-shock proteins (sHsps) are molecular chaperones that play an important protective role against cellular protein misfolding by interacting with partially unfolded proteins on their off-folding pathway, preventing their aggregation. Polyglutamine (polyQ) repeat expansion leads to the formation of fibrillar protein aggregates and neuronal cell death in nine diseases, including Huntington disease and the spinocerebellar ataxias (SCAs). There is evidence that sHsps have a role in suppression of polyQ-induced neurodegeneration; for example, the sHsp alphaB-crystallin (αB-c) has been identified as a suppressor of SCA3 toxicity in a Drosophila model. However, the molecular mechanism for this suppression is unknown. In this …

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The Development Of Signal Transduction Pathways During Epididymal Maturation Is Calcium Dependent, Heath W. Ecroyd, Kelly Asquith, Russell C. Jones, Robert J. Aitken Dec 2011

The Development Of Signal Transduction Pathways During Epididymal Maturation Is Calcium Dependent, Heath W. Ecroyd, Kelly Asquith, Russell C. Jones, Robert J. Aitken

Heath Ecroyd

Capacitation has been correlated with the activation of a cAMP-PKA-dependent signaling pathway leading to protein tyrosine phosphorylation. The ability to exhibit this response to cAMP matures during epididymal maturation in concert with the ability of the sperrnatozoa to capacitate. In this study, we have addressed the mechanisms by which spermatozoa gain the potential to activate this signaling pathway during epididymal maturation. In a modified Tyrode's medium containing 1.7 mM calcium, caput spermatozoa had significantly higher [Ca2+](i) than caudal cells and could not tyrosine phosphorylate in response to cAMP. However, in calcium-depleted medium both caput and caudal cells could exhibit a …

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