User talk:Sandy Harris/MoW: Difference between revisions
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Human [[basophil]]s are a rare [[granulocyte]] cell type accounting for 0.1–1% of white blood cells; these cells contain large numbers of "granules" which store inflammatory mediators, including in particular [[histamine]]. These cells can be cultured readily and studied ''in vitro''. In these cells, exposure to anti-human-IgE [[antibodies]] triggers a "degranulation" process in which the granules fuse with the plasma membrane to release their contents, including histamine, into the extracellular fluid. At high concentrations (>10<sup>−6</sup> M) histamine binds to H<sub>2</sub> receptors on the surface of the basophils, and regulates the basophil degranulation by feedback inhibition. Basophil activation can be measured in several different ways. First, degranulated cells can be stained and then counted; this is a subjective measurement and is prone to variable outcomes depending on the observer. Second, histamine release into the culture medium can be measured using fluorimetric assays. Third, the fusion of cytoplasmatic granules leads to the expression of the marker [[CD63]] on the surface of the basophils; the percentage of basophils that express CD63 can be determined with [[flow-cytometry]], and correlates well with histamine release. | Human [[basophil]]s are a rare [[granulocyte]] cell type accounting for 0.1–1% of white blood cells; these cells contain large numbers of "granules" which store inflammatory mediators, including in particular [[histamine]]. These cells can be cultured readily and studied ''in vitro''. In these cells, exposure to anti-human-IgE [[antibodies]] triggers a "degranulation" process in which the granules fuse with the plasma membrane to release their contents, including histamine, into the extracellular fluid. At high concentrations (>10<sup>−6</sup> M) histamine binds to H<sub>2</sub> receptors on the surface of the basophils, and regulates the basophil degranulation by feedback inhibition. Basophil activation can be measured in several different ways. First, degranulated cells can be stained and then counted; this is a subjective measurement and is prone to variable outcomes depending on the observer. Second, histamine release into the culture medium can be measured using fluorimetric assays. Third, the fusion of cytoplasmatic granules leads to the expression of the marker [[CD63]] on the surface of the basophils; the percentage of basophils that express CD63 can be determined with [[flow-cytometry]], and correlates well with histamine release. | ||
Benveniste and his colleagues found evidence that very high dilutions of anti-immunoglobulin E had an effect on the degranulation of human | Benveniste and his colleagues found evidence that very high dilutions of anti-immunoglobulin E had an effect on the degranulation of human basophils. At the dilutions used, the solutions should have contained only molecules of water, and no molecules of (anti-IgE) at all. Benveniste concluded that the configuration of molecules in water was biologically active. <ref name=Benveniste /> | ||
The French newspaper ''Le Monde'' covered this, referring to ''"la mémoire de la matière"'' (the memory of matter) and ''le souvenir de molécules biologiquement actives'' (recollection [by water] of biologically active molecules). In English, however, the phrase that became widespread was "memory of water". Le Monde considered the paper important, making it a front page story, and correctly pointing out that if this work were correct, it would overthrow many of the foundations of physics. | The French newspaper ''Le Monde'' covered this, referring to ''"la mémoire de la matière"'' (the memory of matter) and ''le souvenir de molécules biologiquement actives'' (recollection [by water] of biologically active molecules). In English, however, the phrase that became widespread was "memory of water". Le Monde considered the paper important, making it a front page story, and correctly pointing out that if this work were correct, it would overthrow many of the foundations of physics. |
Revision as of 06:38, 20 May 2010
Memory of water is a phrase used by homeopaths to explain how the aqueous (water) solutions they use as remedies might produce the results that they claim to see in their patients. Homeopathic remedies deliberately use extremely high dilutions, so it is unlikely that a therapeutic dose contains even a single molecule of substance other than pure water. This has led homeopaths to speculate that a possible explanation for the observed responses is "memory of water"; the water somehow "remembers" the biologically active molecules that it has once been in contact with, and that "memory" produces therapeutic effects.
Chemists and physicists generally see this notion as nonsense. The consensus of scientists working in the field is that liquid water exists as a continuously rearranging hydrogen-bonded network with motions on the picosecond (10−12 s) time scale.[1]. A picture of a quickly rearranging network is very difficult to reconcile with liquid water structures that are sustained for more than a few picoseconds. Accordingly there is no room for a water "memory" in the current scientific view on the liquid.
The Benveniste study
In 1988, a French immunologist, Jacques Benveniste, and a group of colleagues published a paper [2] in the prestigious English journal Nature. Their data indicated that diluted water, ethanol or propanol might retain some qualities of various materials that had once been dissolved in it. In particular, they claimed to have measured effects on human immune response.
Human basophils are a rare granulocyte cell type accounting for 0.1–1% of white blood cells; these cells contain large numbers of "granules" which store inflammatory mediators, including in particular histamine. These cells can be cultured readily and studied in vitro. In these cells, exposure to anti-human-IgE antibodies triggers a "degranulation" process in which the granules fuse with the plasma membrane to release their contents, including histamine, into the extracellular fluid. At high concentrations (>10−6 M) histamine binds to H2 receptors on the surface of the basophils, and regulates the basophil degranulation by feedback inhibition. Basophil activation can be measured in several different ways. First, degranulated cells can be stained and then counted; this is a subjective measurement and is prone to variable outcomes depending on the observer. Second, histamine release into the culture medium can be measured using fluorimetric assays. Third, the fusion of cytoplasmatic granules leads to the expression of the marker CD63 on the surface of the basophils; the percentage of basophils that express CD63 can be determined with flow-cytometry, and correlates well with histamine release.
Benveniste and his colleagues found evidence that very high dilutions of anti-immunoglobulin E had an effect on the degranulation of human basophils. At the dilutions used, the solutions should have contained only molecules of water, and no molecules of (anti-IgE) at all. Benveniste concluded that the configuration of molecules in water was biologically active. [2]
The French newspaper Le Monde covered this, referring to "la mémoire de la matière" (the memory of matter) and le souvenir de molécules biologiquement actives (recollection [by water] of biologically active molecules). In English, however, the phrase that became widespread was "memory of water". Le Monde considered the paper important, making it a front page story, and correctly pointing out that if this work were correct, it would overthrow many of the foundations of physics.
Nature published the article with two unprecedented conditions: first, that the results must first be confirmed by other laboratories; second, that a team selected by Nature be allowed to investigate his laboratory following publication. Benveniste accepted these conditions; the results were replicated in Milan, Italy; in Toronto, Canada; in Tel-Aviv, Israel and in Marseille, France, and the article was accompanied by an editorial titled "When to believe the unbelievable." After publication, the follow-up investigation was conducted by a team including the editor of Nature, Dr John Maddox, American scientific fraud investigator and chemist Walter Stewart, and "professional pseudoscience debunker" James Randi. With the cooperation of Benveniste's team, under double-blind conditions, they failed to replicate the results. Benveniste refused to withdraw his claims, and the team published in the July 1988 a detailed critique of Benveniste’s study. [3] They claimed that the experiments were badly controlled statistically, that measurements that conflicted with the claim had been excluded, that there was insufficient avoidance of contamination, and that there were questions of undisclosed conflict of interest, as the salaries of two coauthors of the published article were paid for under a contract with the French company Boiron et Cie.[3].
Subsequent attempts by other labs to reproduce Benveniste's results have failed to reproduce the effects. [4] [5]
Benveniste has never retracted his claims. In the same issue of Nature that carried the critique, Benveniste vigorously attacked the Nature team’s "mockery of scientific inquiry." [6]. He has maintained his position in later publications as well.
Homeopathic coverage
Despite the general skepticism of scientists, and the failure of others to replicate Benveniste's results, the notion of "memory of water" is still taken seriously among homeopaths. An overview of the issues surrounding the memory of water and its relationship to homeopathic medicine was the subject of a special issue of the leading journal on homeopathy.[7] The articles in this issue propose widely varying mechanisms for water memory, such as: electromagnetic exchange of information between molecules, breaking of temporal symmetry, thermoluminescence, entanglement described by a new quantum theory, formation of hydrogen peroxide, clathrate formation, etc. without any mechanism singularly standing out as the definitive explanation. Some of the proposed mechanisms require revolutionary new physical principles overthrowing much of 20th century physics. Remarkably, all explanations concentrate on water and its alleged special properties, the fact that—according to Benveniste et al.—ethanol and propanol also have memory is completely ignored.
Digtal biology
Benveniste never retracted his claims. On the contrary, later he founded the field of "Digital Biology",[8] which is based on the assumption that molecules emit electromagnetic radiation in the frequency range 20 Hz to 20 kHz,[9] the same range as sound waves audible by humans.[10] By means of an amplifier, electromagnetic coils and a PC sound card Benveniste claimed that he was able to digitize and store the molecular signals. The digital information (possibly after sending it over the internet) could be replayed to a biological system making it believe that it is in the presence of its "favorite molecule". Since Benveniste's description of his experiments is too vague to even begin thinking about trying to reproduce them, and since his theory is not only primitive and underdeveloped, but also in complete contradiction to the well-established principles of molecular spectroscopy, it is fair to call Digital Biology a pseudoscience.
References
- ↑ F. N. Keutsch, J. D. Cruzan, and R. J. Saykally, Chemical Reviews, Vol.103, pp. 2533-2577 (2003)
- ↑ 2.0 2.1 E. Davenas, F. Beauvais, J. Arnara, M. Oberbaum, B. Robinzon, A. Miadonna, A. Tedeschi, B. Pomeranz, P. Fortner, P. Belon, J. Sainte-Laudy, B. Poitevin and J. Benveniste, Human basophil degranulation triggered by very dilute antiserum against IgE, Nature, Vol. 333, pp. 816-818, 30th June, 1988.Free text on DigiBio site. Non-free text on Nature site
- ↑ 3.0 3.1 Maddox, John; James Randi and Walter W. Stewart (28 July 1988). "‘High-dilution’ experiments a delusion" (PDF). Nature 334: 287–290. DOI:10.1038/334287a0. Research Blogging.
- ↑ S. J. Hirst, N. A. Hayes, J. Burridge, F. L. Pearce, J. C. Foreman, Human basophil degranulation is not triggered by very dilute antiserum against human IgE, Nature vol. 366, pp. 525–527 (1993) doi
- ↑ Guggisberg AG, Baumgartner SM, Tschopp CM, and Heusser P (2005) Replication study concerning the effects of homeopathic dilutions of histamine on human basophil degranulation in vitro. Complement Ther Med 13:91-100.
- ↑ J. Benveniste, Dr Jacques Benveniste replies, News and views, Nature, vol. 334 p. 291 (1988) doi
- ↑ Martin Chaplin, ed. (2007), The Memory of Water Homeopathy. 96:141-230
- Copies of the articles in this special issue are freely available on a private website, along with discussion. Homeopathy Journal Club hosted by Bad Science, a blog by Ben Goldacre
- ↑ Overview of DigiBio Website retrieved May 7, 2009
- ↑ What is Digital Biology? Website retrieved May 7, 2009
- ↑ To avoid misunderstanding: electromagnetic (EM) waves have no relationship to sound waves. Sound waves are propagated by material particles and hence cannot propagate in vacuum, while EM waves can. Furthermore, neither theoretical nor experimental molecular spectroscopy can explain the existence of molecular EM waves in this region of extremely low frequencies. Moreover, unless it is shown what feeds them, Benveniste's EM waves seem to contradict the principle of conservation of energy