bert wrote:I'm a capricorn and we capricorns are very sceptical about astrological claims.

Bert

Shrunk wrote:

kyrani99 wrote:when did I deny criticizing?

Right here:

kyrani99 wrote:Whether I had remembered things in a jumble or not the fact is I reacted to a paranormal experience of possible danger. I haven't criticized anyone for pointing out any inconsistencies. I haven't called anyone bad for their comments. So why the animosity?

kyrani99 wrote::lol: Speaking of untruths, I have taken a closer look at the Ames test. It is groundless. All the chemicals that they are naming mutagens do no cause mutations that lead to a beneficial change in the bacteria. And the funny thing is that all of the so called mutagens (including natural foods, which some are claiming are worse than additives and toxins) ALL bring about the same changes. That is thousands of substances, including normal natural foods like mushrooms and red meat... all do the same trick and all in just 24 hours! . Bruce Ames and others, who are saying this, need to prove the matter and I do not see that they have done this.

ScholasticSpastic wrote:

kyrani99 wrote::lol: Speaking of untruths, I have taken a closer look at the Ames test. It is groundless. All the chemicals that they are naming mutagens do no cause mutations that lead to a beneficial change in the bacteria. And the funny thing is that all of the so called mutagens (including natural foods, which some are claiming are worse than additives and toxins) ALL bring about the same changes. That is thousands of substances, including normal natural foods like mushrooms and red meat... all do the same trick and all in just 24 hours! . Bruce Ames and others, who are saying this, need to prove the matter and I do not see that they have done this.

What a laughably stupid paragraph this is!

I don't see how anyone can justify arguing against a theory when they haven't even begun to learn about some of the science behind it. You're not technically making an argument from incredulity, but also kind of you are, simply because you understand so little about what you're attempting to argue against that you cannot help but make all your arguments into arguments from incredulity.

kyrani99 wrote:
Easy to try an fob it off as incredulity. But you need to convince me that all of these thousands of different substances, including many natural foods, all give rise to spontaneous mutations (RANDOM), which become subject to natural selection and give rise to the SAME result AND in just 24 hours.

kyrani99 wrote::lol: Speaking of untruths, I have taken a closer look at the Ames test. It is groundless. All the chemicals that they are naming mutagens do no cause mutations that lead to a beneficial change in the bacteria. And the funny thing is that all of the so called mutagens (including natural foods, which some are claiming are worse than additives and toxins) ALL bring about the same changes. That is thousands of substances, including normal natural foods like mushrooms and red meat... all do the same trick and all in just 24 hours! . Bruce Ames and others, who are saying this, need to prove the matter and I do not see that they have done this.

There is a far simpler, far more realistic explanation. The bacteria revert back to His + when there is a threat to their survival. This is a characteristic that is seen in other species too. I saw this when I was in my late teens. My father had two olive trees in the back yard. When the olive trees bore a very low yield he would perform a superficial ring barking the next year before the trees were to bear olives. This caused the trees to bear a massive crop, three or four fold in some cases. It is a survival mechanism. The bacteria do the same thing.

If you add a substance that is harmful then they will move to make the changes they need to ensure their survival. So the test for mutagens is baloney. Now I'm going back to the mice and rats that I have been researching because I'll bet the same sort of false claims are made there too.

kyrani99 wrote::lol: Speaking of untruths, I have taken a closer look at the Ames test. It is groundless. All the chemicals that they are naming mutagens do no cause mutations that lead to a beneficial change in the bacteria.

And the funny thing is that all of the so called mutagens

(including natural foods, which some are claiming are worse than additives and toxins)

ALL bring about the same changes.

That is thousands of substances, including normal natural foods like mushrooms and red meat... all do the same trick and all in just 24 hours! .

General procedure[edit]
The Ames test uses several strains of the bacterium Salmonella typhimurium that carry mutations in genes involved in histidine synthesis. These strains are auxotrophic mutants, i.e. they require histidine for growth, but cannot produce it. The method tests the capability of the tested substance in creating mutations that result in a return to a "prototrophic" state, so that the cells can grow on a histidine-free medium.

The tester strains are specially constructed to detect either frameshift (e.g. strains TA-1537 and TA-1538) or point (e.g. strain TA-1531) mutations in the genes required to synthesize histidine, so that mutagens acting via different mechanisms may be identified. Some compounds are quite specific, causing reversions in just one or two strains.[4] The tester strains also carry mutations in the genes responsible for lipopolysaccharide synthesis, making the cell wall of the bacteria more permeable,[5] and in the excision repair system to make the test more sensitive.[6] Rat liver extract is optionally added to simulate the effect of metabolism, as some compounds, like benzo[a]pyrene, are not mutagenic themselves but their metabolic products are.[3]

The bacteria are spread on an agar plate with small amount of histidine. This small amount of histidine in the growth medium allows the bacteria to grow for an initial time and have the opportunity to mutate. When the histidine is depleted only bacteria that have mutated to gain the ability to produce its own histidine will survive. The plate is incubated for 48 hours. The mutagenicity of a substance is proportional to the number of colonies observed.

Rumraket wrote:

kyrani99 wrote::lol: Speaking of untruths, I have taken a closer look at the Ames test. It is groundless. All the chemicals that they are naming mutagens do no cause mutations that lead to a beneficial change in the bacteria.

[Citation Needed]

The Ames test http://www.biology-pages.info/A/AmesTest.html
The article says:
"The bacterium used in the test is a strain of Salmonella typhimurium have been altered so that they carry a defective (mutant) gene making it unable to synthesize the amino acid histidine (His) from the ingredients in its culture medium. However, some types of mutations (including this one) can be reversed, a back mutation, with the gene regaining its function. These revertants are able to grow on a medium lacking histidine."

That is at the end of a positive test the bacteria no longer need histidine to grow because they can make their own. So they have undergone a back mutation, which makes the gene functional again. A "gain of function" is a beneficial change in the bacteria.

However the bacteria can make the change spontaneously. In this case it is called a false positive. It differs from a positive in that the colonies of growing bacteria are sparse rather than crowded, large colonies.

A positive result in an Ames test suggests that a chemical can produce mutations.

And the funny thing is that all of the so called mutagens

[Citation Needed]
http://www.ncbi.nlm.nih.gov/books/NBK216630/
"The most widely used of the mutagenicity assays is the Salmonella plate incorporation test, commonly known as the Ames test. In this assay, a chemical is tested for its ability to induce mutations in different strains of a bacterium (Salmonella typhimurium). Most chemical carcinogens and mutagens do not interact directly with DNA. They require alteration by enzymes in order to become activated. This process of “metabolic activation” cannot usually be accomplished by enzymes present in bacteria. Therefore, in the Salmonella test, an extract of mammalian liver (usually from the rat) is added to provide the enzymes necessary for metabolic activation."

In their summary and conclusions they write:
"Considerable attention has recently been directed toward the presence of mutagenic activity in foods. Many vegetables contain mutagenic flavonoids such as quercetin, kaempferol, and their glycosides. Furthermore, some substances found in foods can enhance or inhibit the mutagenic activity of other compounds. Mutagens in charred meat and fish are produced during the pyrolysis of proteins that occurs when foods are cooked at very high temperatures. Normal cooking of meat at lower temperatures can also result in the production of mutagens. Smoking of foods as well as charcoal broiling results in the deposition of mutagenic and carcinogenic polynuclear aromatic compounds such as benzo[a]pyrene on the surface of the food."


Everything from asbestos and benzene (with a little mouse liver extract to get enzymatic metabolites) to processed foods, to natural foods have been tested.

(including natural foods, which some are claiming are worse than additives and toxins)

[Citation Needed]
http://news.heartland.org/newspaper-art ... -beverages

ALL bring about the same changes.

[Citation Needed]
see above.

If they did tests and then did genome sequencing and found all the different mutations then that is a bit different. But the Ames test, which is widely used as a preliminary test for mutagens and thus possible carcinogens (which IMO are a joke anyway), relies entirely on the bacteria reverting back to making their own histidine and that requires a change in the histidine operon. And of course a permanent change is called a mutation. So all the substances have to somehow help make that change, maybe not in the same way but at least with the same effect.

also http://www.the-scientist.com/?articles. ... ivitamins/

http://ntp.niehs.nih.gov/testing/types/ ... index.html
"Spontaneous mutations (those that occur by chance, not by chemical treatment) will appear as colonies on the control petri dishes. If the test chemical was mutagenic to any particular strain of bacterium, the number of histidine-independent colonies arising on those plates will be significantly greater than the corresponding control plates for that strain of bacteria. The positive control plates are also counted, and the number of mutant colonies appearing on them must be significantly increased over the spontaneous control number for the test to be considered valid. "

The fact that the bacteria can spontaneous revert back makes me wonder what the alteration to the genome is all about. It seems that these alterations have to do with how the histidine operon works. In the presence of histidine in the media/bacterial environment, the bacteria doesn't need to make their own histidine and hence turns off the gene sequence through one or more of its regulatory elements. That is that the alterations made are really regulatory mutations.
https://cshmonographs.org/index.php/mon ... /view/4128

That is thousands of substances, including normal natural foods like mushrooms and red meat... all do the same trick and all in just 24 hours! .

[Citation Needed]

kyrani99 wrote:

Rumraket wrote:

kyrani99 wrote::lol: Speaking of untruths, I have taken a closer look at the Ames test. It is groundless. All the chemicals that they are naming mutagens do no cause mutations that lead to a beneficial change in the bacteria.

[Citation Needed]

The Ames test http://www.biology-pages.info/A/AmesTest.html
The article says:
"The bacterium used in the test is a strain of Salmonella typhimurium have been altered so that they carry a defective (mutant) gene making it unable to synthesize the amino acid histidine (His) from the ingredients in its culture medium. However, some types of mutations (including this one) can be reversed, a back mutation, with the gene regaining its function. These revertants are able to grow on a medium lacking histidine."

kyrani99 wrote:That is at the end of a positive test the bacteria no longer need histidine to grow because they can make their own. So they have undergone a back mutation, which makes the gene functional again. A "gain of function" is a beneficial change in the bacteria.

kyrani99 wrote:However the bacteria can make the change spontaneously.

kyrani99 wrote:In this case it is called a false positive.

kyrani99 wrote:

Shrunk wrote:

kyrani99 wrote:when did I deny criticizing?

Right here:

kyrani99 wrote:Whether I had remembered things in a jumble or not the fact is I reacted to a paranormal experience of possible danger. I haven't criticized anyone for pointing out any inconsistencies. I haven't called anyone bad for their comments. So why the animosity?

You show me where have I criticized anyone for inconsistencies and called them bad!

If I was a real liar then I could run for the American presidency and you'd vote for me!

Rumraket wrote:

kyrani99 wrote:

Rumraket wrote:

kyrani99 wrote::lol: Speaking of untruths, I have taken a closer look at the Ames test. It is groundless. All the chemicals that they are naming mutagens do no cause mutations that lead to a beneficial change in the bacteria.

[Citation Needed]

The Ames test http://www.biology-pages.info/A/AmesTest.html
The article says:
"The bacterium used in the test is a strain of Salmonella typhimurium have been altered so that they carry a defective (mutant) gene making it unable to synthesize the amino acid histidine (His) from the ingredients in its culture medium. However, some types of mutations (including this one) can be reversed, a back mutation, with the gene regaining its function. These revertants are able to grow on a medium lacking histidine."

This citation fails to prove evidence of the claim that none of the changes are beneficial.

bert wrote:"then it would be astronomical odds that this particular type of mutation is reversed"

The number of nucleotides in the DNA of a bacterial cell is a few million. I couldn't find how many bacteria there are in a colony forming unit on a Petri dish

kyrani99 wrote:And notice they don't talk about "gene repair", which is what you would expect if it was a random change. Instead they talk about "mutation reversal". The truth here is that the change.. i.e., mutation.. is an action that the gene undergoes when there are either low levels of histidine or no histidine present in the bacterial environment, the broth if it is in the lab. The reason is that this is part of the way the his operon works.

kyrani99 wrote: The biosynthesis of histidine is very costly for the bacterium, at 41 ATPs. So it will make sure it does not make histidine if it has it available. The mechanism is an attenuation mechanism but in any case the "mutation" is a deliberate change and not some accident.

kyrani99 wrote:So it is the BACTERIA that cause the mutation as part of the his operon function

Rumraket wrote:Sorry, everything you say is wrong.