flatfish
03-19-2007, 07:22 PM
----- Original Message -----
From: "Terry S. Singeltary Sr." <flounder9@verizon.net>
To: "Bovine Spongiform Encephalopathy" <BSE-L@aegee.org>
Cc: <cjdvoice@yahoogroups.com>; <madcow@lists.iatp.org>;
<SANET-MG@LISTS.IFAS.UFL.EDU>; "Jim Woodward" <jbw@frii.com>
Sent: Monday, March 19, 2007 11:30 AM
Subject: [CJDVoice] Adsorption of Pathogenic Prion Protein to Quartz Sand
Subject: Adsorption of Pathogenic Prion Protein to Quartz Sand
Date: March 19, 2007 at 9:09 am PST
Environ. Sci. Technol., ASAP Article 10.1021/es062122i S0013-936X(06)02122-5
Web Release Date: March 6, 2007 Copyright © 2007 American Chemical Society
Adsorption of Pathogenic Prion Protein to Quartz Sand
Xin Ma, Craig H. Benson, Debbie McKenzie, Judd M. Aiken, and Joel A.
Pedersen*
Department of Soil Science, University of Wisconsin, Madison, Wisconsin
53706, Department of Civil and Environmental Engineering, University of
Wisconsin, Madison, Wisconsin 53706, Department of Comparative Biosciences,
University of Wisconsin, Madison, Wisconsin 53706, and Molecular and
Environmental Toxicology Center, University of Wisconsin, Madison, Wisconsin
53706
Received for review September 6, 2006
Revised manuscript received January 12, 2007
Accepted January 29, 2007
Abstract:
Management responses to prion diseases of cattle, deer, and elk create a
significant need for safe and effective disposal of infected carcasses and
other materials. Furthermore, soil may contribute to the horizontal
transmission of sheep scrapie and cervid chronic wasting disease by serving
as an environmental reservoir for the infectious agent. As an initial step
toward understanding prion mobility in porous materials such as soil and
landfilled waste, the influence of pH and ionic strength (I) on pathogenic
prion protein (PrPSc) properties (viz. aggregation state and -potential) and
adsorption to quartz sand was investigated. The apparent average isoelectric
point of PrPSc aggregates was 4.6. PrPSc aggregate size was largest between
pH 4 and 6, and increased with increasing I at pH 7. Adsorption to quartz
sand was maximal near the apparent isoelectric point of PrPSc aggregates and
decreased as pH either declined or increased. PrPSc adsorption increased as
suspension I increased, and reached an apparent plateau at I ~ 0.1 M. While
trends with pH and I in PrPSc attachment to quartz surfaces were consistent
with predictions based on Born-DLVO theory, non-DLVO forces appeared to
contribute to adsorption at pH 7 and 9 (I = 10 mM). Our findings suggest
that disposal strategies that elevate pH (e.g., burial in lime or fly ash),
may increase PrPSc mobility. Similarly, PrPSc mobility may increase as a
landfill ages, due to increases in pH and decreases in I of the leachate.
http://pubs.acs.org/cgi-bin/abstract.cgi/esthag/asap/abs/es062122i.html
TSS
Study: Prions likely more mobile in alkaline soils
March 19, 2007
Prions, the rogue proteins that cause chronic wasting disease and similar
maladies, may be more mobile in soil that is more alkaline, suggests a new
study by University of Wisconsin-Madison researchers.
That finding has implications for the safe disposal of carcasses of animals
infected with chronic wasting disease, "mad cow" disease, scrapie and other
prion diseases. Prions from those carcasses can remain infectious in the
soil for at least three years. Soil alkalinity varies considerably but can
be relatively high in older landfills, especially if lime is spread on the
carcasses to speed decomposition.
The study is reported in the April 15 issue of the journal Environmental
Science and Technology.
The UW-Madison research team found that as alkalinity increases, prions are
less likely to adhere to particles of quartz, a common soil mineral, and are
therefore expected to be more mobile, explains Joel Pedersen, an assistant
professor of soil science.
Movement of prions in the soil could be a good or bad thing, depending on
the situation, Pedersen explains. For example, if they move away from the
surface, they're less likely to be ingested by animals.
"Those that remain near the surface would more accessible to animals and
might therefore lead to the spread of chronic wasting," he points out.
On the other hand, prions that are more mobile might be more likely to
migrate through a landfill, he adds.
"In a landfill, if prions are mobile, they could be transported down through
the waste, where they could enter the landfill's leachate collection system,
and from there be directed to wastewater treatment plants. If prions survive
wastewater treatment, they would be released back into the environment in
treated water or in the sludge," Pedersen says.
However, Pedersen cautions that his findings are from a highly simplified
experimental system, and that any assessments about the safety of
landfilling carcasses would have to be based on studies of how prions behave
in municipal solid waste and the soils used in landfills. The research team
is now undertaking such studies.
He also says that the findings don't necessarily mean that it's a bad idea
to bury carcasses with lime.
"The lime treatment could destroy some prions," he says. "We don't know yet.
It's only the prions that might survive that might be more mobile."
The experiment that generated these findings involved mixing a solution that
included prions and pure quartz sand, letting it stand for a specific period
of time and then measuring how many prions remained free in the solution. In
a real-world setting the prions would in be a mix of landfill materials, not
just quartz, and the soil solution would be percolating downward.
For the next set of experiments, the researchers are flowing water through
columns of materials like those found in carcass disposal sites, including
both soil and solid waste, Pedersen explains.
Other members of the research team include Xin Ma, a postdoctoral researcher
in the UW-Madison's Department of Soil Science; Craig Bensen in the
Department of Civil and Environmental Engineering; and Judd Aiken and Debbie
McKenzie in the Department of Comparative Biosciences.
http://www.news.wisc.edu/13583.html
Evidence For CWD/Mad Cow/TSEs In The Environment
http://www.rense.com/general34/evide.htm
Subject: Infectious Prions in the Saliva and Blood of Deer with Chronic
Wasting Disease
Date: October 5, 2006 at 1:45 pm PST
http://www.microbes.info/forums/index.php?showtopic=384&pid=484&st=0&#entry484
TSS
From: "Terry S. Singeltary Sr." <flounder9@verizon.net>
To: "Bovine Spongiform Encephalopathy" <BSE-L@aegee.org>
Cc: <cjdvoice@yahoogroups.com>; <madcow@lists.iatp.org>;
<SANET-MG@LISTS.IFAS.UFL.EDU>; "Jim Woodward" <jbw@frii.com>
Sent: Monday, March 19, 2007 11:30 AM
Subject: [CJDVoice] Adsorption of Pathogenic Prion Protein to Quartz Sand
Subject: Adsorption of Pathogenic Prion Protein to Quartz Sand
Date: March 19, 2007 at 9:09 am PST
Environ. Sci. Technol., ASAP Article 10.1021/es062122i S0013-936X(06)02122-5
Web Release Date: March 6, 2007 Copyright © 2007 American Chemical Society
Adsorption of Pathogenic Prion Protein to Quartz Sand
Xin Ma, Craig H. Benson, Debbie McKenzie, Judd M. Aiken, and Joel A.
Pedersen*
Department of Soil Science, University of Wisconsin, Madison, Wisconsin
53706, Department of Civil and Environmental Engineering, University of
Wisconsin, Madison, Wisconsin 53706, Department of Comparative Biosciences,
University of Wisconsin, Madison, Wisconsin 53706, and Molecular and
Environmental Toxicology Center, University of Wisconsin, Madison, Wisconsin
53706
Received for review September 6, 2006
Revised manuscript received January 12, 2007
Accepted January 29, 2007
Abstract:
Management responses to prion diseases of cattle, deer, and elk create a
significant need for safe and effective disposal of infected carcasses and
other materials. Furthermore, soil may contribute to the horizontal
transmission of sheep scrapie and cervid chronic wasting disease by serving
as an environmental reservoir for the infectious agent. As an initial step
toward understanding prion mobility in porous materials such as soil and
landfilled waste, the influence of pH and ionic strength (I) on pathogenic
prion protein (PrPSc) properties (viz. aggregation state and -potential) and
adsorption to quartz sand was investigated. The apparent average isoelectric
point of PrPSc aggregates was 4.6. PrPSc aggregate size was largest between
pH 4 and 6, and increased with increasing I at pH 7. Adsorption to quartz
sand was maximal near the apparent isoelectric point of PrPSc aggregates and
decreased as pH either declined or increased. PrPSc adsorption increased as
suspension I increased, and reached an apparent plateau at I ~ 0.1 M. While
trends with pH and I in PrPSc attachment to quartz surfaces were consistent
with predictions based on Born-DLVO theory, non-DLVO forces appeared to
contribute to adsorption at pH 7 and 9 (I = 10 mM). Our findings suggest
that disposal strategies that elevate pH (e.g., burial in lime or fly ash),
may increase PrPSc mobility. Similarly, PrPSc mobility may increase as a
landfill ages, due to increases in pH and decreases in I of the leachate.
http://pubs.acs.org/cgi-bin/abstract.cgi/esthag/asap/abs/es062122i.html
TSS
Study: Prions likely more mobile in alkaline soils
March 19, 2007
Prions, the rogue proteins that cause chronic wasting disease and similar
maladies, may be more mobile in soil that is more alkaline, suggests a new
study by University of Wisconsin-Madison researchers.
That finding has implications for the safe disposal of carcasses of animals
infected with chronic wasting disease, "mad cow" disease, scrapie and other
prion diseases. Prions from those carcasses can remain infectious in the
soil for at least three years. Soil alkalinity varies considerably but can
be relatively high in older landfills, especially if lime is spread on the
carcasses to speed decomposition.
The study is reported in the April 15 issue of the journal Environmental
Science and Technology.
The UW-Madison research team found that as alkalinity increases, prions are
less likely to adhere to particles of quartz, a common soil mineral, and are
therefore expected to be more mobile, explains Joel Pedersen, an assistant
professor of soil science.
Movement of prions in the soil could be a good or bad thing, depending on
the situation, Pedersen explains. For example, if they move away from the
surface, they're less likely to be ingested by animals.
"Those that remain near the surface would more accessible to animals and
might therefore lead to the spread of chronic wasting," he points out.
On the other hand, prions that are more mobile might be more likely to
migrate through a landfill, he adds.
"In a landfill, if prions are mobile, they could be transported down through
the waste, where they could enter the landfill's leachate collection system,
and from there be directed to wastewater treatment plants. If prions survive
wastewater treatment, they would be released back into the environment in
treated water or in the sludge," Pedersen says.
However, Pedersen cautions that his findings are from a highly simplified
experimental system, and that any assessments about the safety of
landfilling carcasses would have to be based on studies of how prions behave
in municipal solid waste and the soils used in landfills. The research team
is now undertaking such studies.
He also says that the findings don't necessarily mean that it's a bad idea
to bury carcasses with lime.
"The lime treatment could destroy some prions," he says. "We don't know yet.
It's only the prions that might survive that might be more mobile."
The experiment that generated these findings involved mixing a solution that
included prions and pure quartz sand, letting it stand for a specific period
of time and then measuring how many prions remained free in the solution. In
a real-world setting the prions would in be a mix of landfill materials, not
just quartz, and the soil solution would be percolating downward.
For the next set of experiments, the researchers are flowing water through
columns of materials like those found in carcass disposal sites, including
both soil and solid waste, Pedersen explains.
Other members of the research team include Xin Ma, a postdoctoral researcher
in the UW-Madison's Department of Soil Science; Craig Bensen in the
Department of Civil and Environmental Engineering; and Judd Aiken and Debbie
McKenzie in the Department of Comparative Biosciences.
http://www.news.wisc.edu/13583.html
Evidence For CWD/Mad Cow/TSEs In The Environment
http://www.rense.com/general34/evide.htm
Subject: Infectious Prions in the Saliva and Blood of Deer with Chronic
Wasting Disease
Date: October 5, 2006 at 1:45 pm PST
http://www.microbes.info/forums/index.php?showtopic=384&pid=484&st=0&#entry484
TSS