Your dishwasher could be harboring dangerous 'super' fungi, says report
In many ways, modern home appliances have made life simpler by reducing the amount of time it takes to clean, cook, and perform other routine household activities. But some of these technological advances may be responsible for increasing the prevalence of harmful "super" pathogens that have grown resistant to stimuli that used to eliminate them, suggests a new report in the British Mycological Society journal Fungal Biology.
According to the report, household appliances that use water, which include dishwashers and washing machines, have become a new point of infestation for potentially deadly fungi like Exophiala dermatitidis and E. phaeomuriformis. These strains and others, which would normally be killed off by heat and detergents, have become tolerant to them, and are now being found in a majority of the household appliances tested. Read more...
Ayurtox for Body Detoxification
Selasa, 01 November 2011
Senin, 31 Oktober 2011
The need for collaborative definitions in neurodegenerative disease research
As the population ages, public concern regarding neurodegenerative diseases is rapidly accelerating. Alzheimer’s Disease (AD) is estimated to effect 5.3 million individuals in the United States alone [1], and treatment options for these patients remain limited. The cause of pathogenesis in AD has remained elusive, severely limiting therapeutic developments.
Alzheimer’s Disease, like many neurodegenerative diseases, is associated with accumulated clumps of protein in the brain, termed “inclusions” or “aggregates”. As a general rule, healthy individuals do not exhibit these inclusions. The protein inclusions associated with Alzheimer brains include amyloid β (Aβ) plaques and tau neurofibrillary tangles; however the extent to which these aggregated proteins contribute to disease, if any, is unknown. Due to the dearth of evidence linking aggregation to disease progression, it has been suggested that aggregates and plaques may actually exist as a protective mechanism to sequester away ‘toxic,’ soluble proteins rather than being toxic themselves [2]. In this theory, soluble protein in the cell somehow acquires a toxic function. In order to minimize interactions with that toxic protein, it is collected and sequestered away within protective ‘aggregates.’
However, identifying toxic, soluble precursors of aggregates in the laboratory has proven extraordinarily difficult. Part of the problem stems from a lack of standard methodology between laboratories – there are essentially as many definitions of ‘soluble’ and ‘aggregated’ protein as there are labs investigating protein solubility. This is further complicated by the variety of models used to re-create and identify these proteins (either from actual post-mortem AD patient brains, animal models, or from cells in a dish) and by attempts to identify the subspecies of proteins within these two solubility pools: as singular, individual (monomeric) proteins congregate, separate protein classes identified as oligomers, proto-fibrils, and fibrils are formed from accumulated protein. These protein classes are loosely defined both by their size and biochemical structure. Recent evidence has implicated the amorphously defined oligomers as being the culpable, ‘toxic’ protein species; however, there is no clear consensus on what exactly oligomers are or how to best isolate them in the laboratory. Indeed, this was the focus of a recent Alzheimer’s Research Forum Webinar in which neuroscientists “met” to discuss the issues surrounding a lack of common terminology and protocols in the field of Aβ oligomer research.
In order to effectively treat neurodegenerative diseases such as Alzheimer’s, it is imperative to identify the cause of degeneration. Until recently, aggregated protein was generally accepted as the toxic species and thus, therapeutic research focused largely on decreasing aggregation. However, if aggregation is actually a protective, compensatory response to toxic oligomers, then preventing the formation of (or breaking up) aggregates might actually be harmful! Instead, it may be more beneficial to the patient to stimulate aggregate formation, thereby decreasing the presence of noxious oligomers. The amorphous definitions applied to different aggregation states necessarily make it difficult for different labs to investigate this issue and build on each other’s findings. Evidence in the Alzheimer’s and larger neurodegenerative disease fields have increasingly implicated oligomeric protein as being toxic to the cell; however, until a clear consensus on how to isolate this protein in a physiologically relevant manner is reached, it will be difficult to empirically assess what role, if any, oligomers play in cell death within the brain. As scientists, we have an enormous obligation to the patient, and to future generations of researchers, to make our terminology and techniques as uniform and transparent as possible. Replicability, the basis of scientific progress, demands nothing less.
--
Terrell Brotherton
Neuroscience Graduate Student (Glass Laboratory)
Recommended Reading
1. Barnes, D.E. and K. Yaffe, The projected effect of risk factor reduction on Alzheimer's disease prevalence. Lancet Neurol, 2011. 10(9): p. 819-28.
2. McLean, C.A., et al., Soluble pool of Abeta amyloid as a determinant of severity of neurodegeneration in Alzheimer's disease. Annals of Neurology, 1999. 46(6): p. 860-6.
 |
| http://www.sfn.org/index.aspx?pagename=brainBriefings_10_unravelingalzheimers |
Alzheimer’s Disease, like many neurodegenerative diseases, is associated with accumulated clumps of protein in the brain, termed “inclusions” or “aggregates”. As a general rule, healthy individuals do not exhibit these inclusions. The protein inclusions associated with Alzheimer brains include amyloid β (Aβ) plaques and tau neurofibrillary tangles; however the extent to which these aggregated proteins contribute to disease, if any, is unknown. Due to the dearth of evidence linking aggregation to disease progression, it has been suggested that aggregates and plaques may actually exist as a protective mechanism to sequester away ‘toxic,’ soluble proteins rather than being toxic themselves [2]. In this theory, soluble protein in the cell somehow acquires a toxic function. In order to minimize interactions with that toxic protein, it is collected and sequestered away within protective ‘aggregates.’
View more presentations from nicowef
However, identifying toxic, soluble precursors of aggregates in the laboratory has proven extraordinarily difficult. Part of the problem stems from a lack of standard methodology between laboratories – there are essentially as many definitions of ‘soluble’ and ‘aggregated’ protein as there are labs investigating protein solubility. This is further complicated by the variety of models used to re-create and identify these proteins (either from actual post-mortem AD patient brains, animal models, or from cells in a dish) and by attempts to identify the subspecies of proteins within these two solubility pools: as singular, individual (monomeric) proteins congregate, separate protein classes identified as oligomers, proto-fibrils, and fibrils are formed from accumulated protein. These protein classes are loosely defined both by their size and biochemical structure. Recent evidence has implicated the amorphously defined oligomers as being the culpable, ‘toxic’ protein species; however, there is no clear consensus on what exactly oligomers are or how to best isolate them in the laboratory. Indeed, this was the focus of a recent Alzheimer’s Research Forum Webinar in which neuroscientists “met” to discuss the issues surrounding a lack of common terminology and protocols in the field of Aβ oligomer research.
View more presentations from nicowef
In order to effectively treat neurodegenerative diseases such as Alzheimer’s, it is imperative to identify the cause of degeneration. Until recently, aggregated protein was generally accepted as the toxic species and thus, therapeutic research focused largely on decreasing aggregation. However, if aggregation is actually a protective, compensatory response to toxic oligomers, then preventing the formation of (or breaking up) aggregates might actually be harmful! Instead, it may be more beneficial to the patient to stimulate aggregate formation, thereby decreasing the presence of noxious oligomers. The amorphous definitions applied to different aggregation states necessarily make it difficult for different labs to investigate this issue and build on each other’s findings. Evidence in the Alzheimer’s and larger neurodegenerative disease fields have increasingly implicated oligomeric protein as being toxic to the cell; however, until a clear consensus on how to isolate this protein in a physiologically relevant manner is reached, it will be difficult to empirically assess what role, if any, oligomers play in cell death within the brain. As scientists, we have an enormous obligation to the patient, and to future generations of researchers, to make our terminology and techniques as uniform and transparent as possible. Replicability, the basis of scientific progress, demands nothing less.
--
Terrell Brotherton
Neuroscience Graduate Student (Glass Laboratory)
Recommended Reading
1. Barnes, D.E. and K. Yaffe, The projected effect of risk factor reduction on Alzheimer's disease prevalence. Lancet Neurol, 2011. 10(9): p. 819-28.
2. McLean, C.A., et al., Soluble pool of Abeta amyloid as a determinant of severity of neurodegeneration in Alzheimer's disease. Annals of Neurology, 1999. 46(6): p. 860-6.
Jumat, 28 Oktober 2011
Neuroethics journal club: Right-brained, wrongly reasoned
Who’d believe there’s a liberal professor (he freely acknowledges he belongs to this group) that’s willing to admit that conservatives might be right about something? Don't get too excited; he also thinks the reasoning that many conservatives use to decide what’s right is all wrong. What’s more, he thinks that neuroscience proves the way that many conservatives reason is wrong. The professor, Dr. John Banja, led a discussion of one of his articles last Wednesday at the second meeting of the Neuroethics Journal Club hosted by the Neuroethics Program at the Emory Center for Ethics.
I had this great idea to summarize Dr. Banja's message with music videos. It turned out to be harder than I thought (but I'm still peppering this post with pop)--there is not one song that has the words "virtue essentialism" in the title, although those words are in the title of Dr. Banja’s article: “Virtue Essentialism, Prototypes, and the Moral Conservative Opposition to Enhancement Technologies: A Neuroethical Critique”. Banja describes virtue essentialism as a type of argument often employed by scholars like Leon Kass, Gilbert Meilander, and Michael Sandel. According to Banja, there are three characteristics of “virtue essentialist” arguments: (1) they invoke concepts like “dignity” as if those concepts have an essence--i.e., definition--that everyone agrees upon, (2) they adopt absolutist positions, because their positions supposedly are based on clearly-defined concepts and, (3) they attack anything that smacks of moral relativism.
You might wonder why you should be worried about this virtue essentialism that Dr. Banja describes. Consider this: virtue essentialist arguments make up the backbone of many of the publications authored by President George W. Bush's President's Council on Bioethics (PCB). W announced he was creating the PCB back in 2001, during the same speech in which he announced he would only allow embryonic stem cell research to be carried out on cell lines already in existence. Bush promised that the council would "consider all of the medical and ethical ramifications of biomedical innovation," and appointed Leon Kass to be the head of the council.
You might still be wondering why this is relevant in today’s political atmosphere. We talked about that at the journal club, too. First I’ll explain how we got there. Banja is not alone in his concern about the arguments made by Kass and others. Ruth Macklin, writing in 2006, dissected just the sort of reasoning--or lack thereof--that Banja wants to attack, all neuroethics style. According to Macklin, issues in bioethics were not black nor white before these self-styled "conservatives" came along; she explicitly links their appearance to the polarized political climate of the Bush regime during which you were either one of us or one of them. Macklin also observes that Kass and others who call themselves "conservatives" in bioethics are characterized largely by being against anything "artificial: artifical reproduction, artificial life extension, artificial intelligence and artificial life, and, in general, making ourselves 'artificially better'."
Didn't I promise there would be rock? Here's David Byrne on "making ourselves 'artifically better'":
Byrne continues the tradition of rockers confounding us all by writing from a perspective that seems a little--gulp--conservative (cf., Graham Parker's You Can't Be Too Strong.)
What's wrong with virtue essentialism and why do we need neuroscience to figure it out? Banja began by discussing "essentialism," which as you might guess is the view that everything has an essence. There is something about Lady Gaga that is essentially Lady Gaga. You might say she was "born this way" (bad joke, sorry). Essentialism, explained Dr. Banja, has been around at least since the time of Plato, who captured it essence (again, sorry) in the Socratic dialogue with Euthyphro, in which Socrates asks what the essence of “holiness” or “piety” is. Socrates runs into Euthyphro down at the courthouse and, thinking that it might help him defend himself in his upcoming court case, asks Euthyphro for a definition of “piety”. As Dr. Banja emphasized, the best Euthyphro can do is come up with some examples. He fails to define it in a way that Socrates can’t deconstruct. Here’s the moral of the story: if it were true that concepts like "holy" had some essence, then we could somehow discern that essence and know when our actions were holy (or "fair" or "just", etc.).
Then Wittgenstein came along and dared to suggest that we might not classify things based on their essence that our god-given reason is supposed to somehow have access to. Instead, he suggested we categorize things based on "family resemblances"--things that they have in common. Wittgenstein's insights spelled the beginning of the end for essentialism. He was implying that there might not be any source of morals outside of humanity. Maybe there's no right or wrong outside of what we say is right or wrong.
Song time again! Perhaps Stereolab can use their perfect pop powers to help us understand the source of the morals that form the backbone of a society.
The once-firm moral foundation that Wittgenstein started to undermine really crumbled once neuroscience and psychology came into the picture, said Dr. Banja. In the 70s, psychologists like Eleanor Rosch began to test how people categorize. These experiments gave rise to prototype theory, a theory that holds that we are able to classify things not because our reason has access to their essence, but because our brains build prototypes. Such prototypes are the “statistical central tendency of a body of concrete exemplars,” to recycle Dr. Banja’s quote from philosopher Andy Clark. In other words, we supposedly classify things by keeping a running average for every category and by measuring the distance of any item we are classifying from the average. I would show you an image from a study Dr. Banja described so that we could understand prototype theory, but in the spirit of this semi-musical post, I think I have to link to songs that neuroscience grad student Laura Mariani mentioned at the journal club. This music, composed by Komar & Molamid and David Soldier, is based on the results of an on-line survey. Click on the links to hear the “prototypes” of what people consider to be the "most wanted song" and "most unwanted song".
Prototype theory, concluded Dr.Banja, presents some problems for virtue essentialist arguments as defined above. It holds that there can be no completely objective definition of concepts like "dignity". Hence, anyone who argues against something like cognitive enhancement because they feel it degrades dignity will have to accept that their idea of what dignity means might not be agreed upon by everyone. This is a good result. It replaces the moral majority with a democratic process of ethics.
In closing, we discussed why virtue essentialism seems to work, even if it is flawed. Dr. Banja recalled the points he made at the end of his article: it works because it appeals to people. It plays their heartstrings. The excesses of the Bush administration showed that Republicans had learned how to hit the right notes to get all the votes, according to Dr. Banja. My labmate Lukas Hoffman countered that you could say the same thing about the Democrats. With the Tea Party on one hand and Occupy Wall Street on the other, it’s certain that people are feeling like something is wrong more and more, and believing that they know what that is. How can they be reminded that everything might not be what it seems? Education is key, offered MD/PhD student Orion Kiefer. And he's right. Anyone who has a sound grasp of science will understand that theories can sometimes be overturned, even theories about right and wrong, and that there’s always room for debate.
Next month's meeting of the journal club will take place November 16th from 1-2pm. You can RSVP by sending an e-mail to neuroethics@emory.edu. Dr. Paul Root Wolpe, director of Emory's Center for Ethics, will facilitate a discussion on emerging technologies and lie detection.
-- David Nicholson
Neuroscience Graduate Student (Sober Lab)
I leave you with one last tune to inculcate you against the siren song of anybody that would make appeals to your gut feelings about what’s right and what’s wrong.
I had this great idea to summarize Dr. Banja's message with music videos. It turned out to be harder than I thought (but I'm still peppering this post with pop)--there is not one song that has the words "virtue essentialism" in the title, although those words are in the title of Dr. Banja’s article: “Virtue Essentialism, Prototypes, and the Moral Conservative Opposition to Enhancement Technologies: A Neuroethical Critique”. Banja describes virtue essentialism as a type of argument often employed by scholars like Leon Kass, Gilbert Meilander, and Michael Sandel. According to Banja, there are three characteristics of “virtue essentialist” arguments: (1) they invoke concepts like “dignity” as if those concepts have an essence--i.e., definition--that everyone agrees upon, (2) they adopt absolutist positions, because their positions supposedly are based on clearly-defined concepts and, (3) they attack anything that smacks of moral relativism.
You might wonder why you should be worried about this virtue essentialism that Dr. Banja describes. Consider this: virtue essentialist arguments make up the backbone of many of the publications authored by President George W. Bush's President's Council on Bioethics (PCB). W announced he was creating the PCB back in 2001, during the same speech in which he announced he would only allow embryonic stem cell research to be carried out on cell lines already in existence. Bush promised that the council would "consider all of the medical and ethical ramifications of biomedical innovation," and appointed Leon Kass to be the head of the council.
You might still be wondering why this is relevant in today’s political atmosphere. We talked about that at the journal club, too. First I’ll explain how we got there. Banja is not alone in his concern about the arguments made by Kass and others. Ruth Macklin, writing in 2006, dissected just the sort of reasoning--or lack thereof--that Banja wants to attack, all neuroethics style. According to Macklin, issues in bioethics were not black nor white before these self-styled "conservatives" came along; she explicitly links their appearance to the polarized political climate of the Bush regime during which you were either one of us or one of them. Macklin also observes that Kass and others who call themselves "conservatives" in bioethics are characterized largely by being against anything "artificial: artifical reproduction, artificial life extension, artificial intelligence and artificial life, and, in general, making ourselves 'artificially better'."
Didn't I promise there would be rock? Here's David Byrne on "making ourselves 'artifically better'":
Byrne continues the tradition of rockers confounding us all by writing from a perspective that seems a little--gulp--conservative (cf., Graham Parker's You Can't Be Too Strong.)
What's wrong with virtue essentialism and why do we need neuroscience to figure it out? Banja began by discussing "essentialism," which as you might guess is the view that everything has an essence. There is something about Lady Gaga that is essentially Lady Gaga. You might say she was "born this way" (bad joke, sorry). Essentialism, explained Dr. Banja, has been around at least since the time of Plato, who captured it essence (again, sorry) in the Socratic dialogue with Euthyphro, in which Socrates asks what the essence of “holiness” or “piety” is. Socrates runs into Euthyphro down at the courthouse and, thinking that it might help him defend himself in his upcoming court case, asks Euthyphro for a definition of “piety”. As Dr. Banja emphasized, the best Euthyphro can do is come up with some examples. He fails to define it in a way that Socrates can’t deconstruct. Here’s the moral of the story: if it were true that concepts like "holy" had some essence, then we could somehow discern that essence and know when our actions were holy (or "fair" or "just", etc.).
Then Wittgenstein came along and dared to suggest that we might not classify things based on their essence that our god-given reason is supposed to somehow have access to. Instead, he suggested we categorize things based on "family resemblances"--things that they have in common. Wittgenstein's insights spelled the beginning of the end for essentialism. He was implying that there might not be any source of morals outside of humanity. Maybe there's no right or wrong outside of what we say is right or wrong.
Song time again! Perhaps Stereolab can use their perfect pop powers to help us understand the source of the morals that form the backbone of a society.
The once-firm moral foundation that Wittgenstein started to undermine really crumbled once neuroscience and psychology came into the picture, said Dr. Banja. In the 70s, psychologists like Eleanor Rosch began to test how people categorize. These experiments gave rise to prototype theory, a theory that holds that we are able to classify things not because our reason has access to their essence, but because our brains build prototypes. Such prototypes are the “statistical central tendency of a body of concrete exemplars,” to recycle Dr. Banja’s quote from philosopher Andy Clark. In other words, we supposedly classify things by keeping a running average for every category and by measuring the distance of any item we are classifying from the average. I would show you an image from a study Dr. Banja described so that we could understand prototype theory, but in the spirit of this semi-musical post, I think I have to link to songs that neuroscience grad student Laura Mariani mentioned at the journal club. This music, composed by Komar & Molamid and David Soldier, is based on the results of an on-line survey. Click on the links to hear the “prototypes” of what people consider to be the "most wanted song" and "most unwanted song".
Prototype theory, concluded Dr.Banja, presents some problems for virtue essentialist arguments as defined above. It holds that there can be no completely objective definition of concepts like "dignity". Hence, anyone who argues against something like cognitive enhancement because they feel it degrades dignity will have to accept that their idea of what dignity means might not be agreed upon by everyone. This is a good result. It replaces the moral majority with a democratic process of ethics.
In closing, we discussed why virtue essentialism seems to work, even if it is flawed. Dr. Banja recalled the points he made at the end of his article: it works because it appeals to people. It plays their heartstrings. The excesses of the Bush administration showed that Republicans had learned how to hit the right notes to get all the votes, according to Dr. Banja. My labmate Lukas Hoffman countered that you could say the same thing about the Democrats. With the Tea Party on one hand and Occupy Wall Street on the other, it’s certain that people are feeling like something is wrong more and more, and believing that they know what that is. How can they be reminded that everything might not be what it seems? Education is key, offered MD/PhD student Orion Kiefer. And he's right. Anyone who has a sound grasp of science will understand that theories can sometimes be overturned, even theories about right and wrong, and that there’s always room for debate.
Next month's meeting of the journal club will take place November 16th from 1-2pm. You can RSVP by sending an e-mail to neuroethics@emory.edu. Dr. Paul Root Wolpe, director of Emory's Center for Ethics, will facilitate a discussion on emerging technologies and lie detection.
-- David Nicholson
Neuroscience Graduate Student (Sober Lab)
I leave you with one last tune to inculcate you against the siren song of anybody that would make appeals to your gut feelings about what’s right and what’s wrong.
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