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Artificial sweeteners Anonymous 16/02/21(Sun)10:07 No. 16288 ID: f705da
16288

File 14560456503.png - (28.70KB , 787x653 , s.png )

Supposing a given artificial sweetener -- say, saccharine or aspartame -- was a carcinogen, what kind of cancer would it produce and by what mechanism?
If this question is too hypothetical to answer, by what mechanism would ingesting a non-toxic chemical cause cancer?


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Anonymous 16/02/23(Tue)01:38 No. 16289 ID: 0500c2

Cancer is caused by some kind of mechanism damaging the DNA of cells on contact, producing a random mutation.

Since we're talking ingestion, it would have to be some kind of gastrointestinal cancer, of which there are several varieties. We can eliminate mouth or throat cancer if we assume the chemical is inert in its base state and only becomes carcinogenic once altered by the process of digestion. That pretty much leaves colon cancer. It could happen if this altered chemical irritated or otherwise physically damaged the lining of the colon. Continued ingestion of this chemical would cause chronic irritation of the colon, in much the same way smoking does for the lungs. That could lead to cancer.


Note: You can create em-dashes by holding the alt key, pressing 0151 on the numpad,and then releasing the alt key, as demonstrated here: — . This is a superior alternative to using two en-dashes.


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Anonymous 16/02/23(Tue)22:01 No. 16290 ID: d8da56

>>16289
Okay, sure, but do we get from irritated tissue to mutated genetic material? I can understand how something like electromagnetic radiation, which can pass through matter and damage the molecular structure of DNA, could cause it, but how would a chemical do it? Is DNA directly exposed to chemicals being metabolized by or otherwise passing through cells such that it can react with them?


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Anonymous 16/03/07(Mon)16:19 No. 16296 ID: cad79b

//are there even papers about knowledge of effects and constituents?

Earlier I asked for a suggestion for a question on the survey that would be important and policy reelvant in the immediate furutre. However, my interests have drifted as I'm getting more familiar with the general topic and the survye. I have found that many of the questions that do interest me onthe survey have been covered already in the literature,a nd the datanalsysies already done of the data from the sruvey(albeit in differnet years). My criterion for ideal project in impact, tractability and neglectness. I feel yes high impact and somewhat tractable (it has been hard to figure out a systematic review, since one relevant for the data often doesn't have papers enough to do, since if it ididn then it wouldn't be neglected enough to study interest me, which is the third criterion.

remember to check that I don't have to renaalse the data from toher papers if it doesn't already indicative something about knowledge --> politilca uspport..... maybe I shoulda.just pick like 3+ papers to search on


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Anonymous 18/11/19(Mon)08:45 No. 16722 ID: d40656

>>16288
Neither sweetener could even hypothetically act as carcinogen due to the mechanisms of how DNA is mutated.

The closest way would be if the metabolic path to break down either sweetener involved the production of a reactive oxygen species (like peroxide) but even then, metabolic degregation of fats normally results on this so our bodies have protiens to deal with this.

On a slightly related note, azo compounds, which we use to color some foods like starbucks drinks are carcinogenic due to the fact they're aromatic.


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Anonymous 18/11/21(Wed)16:41 No. 16723 ID: be6f8f

>>16722
>On a slightly related note, azo compounds, which we use to color some foods like starbucks drinks are carcinogenic due to the fact they're aromatic.
Great, so that's relevant to the second half of my question. How would ingesting such a compound cause cancer?


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Anonymous 18/11/23(Fri)09:26 No. 16724 ID: d40656

>>16723
Via intercalation, they're planer (flat) molocules and so they have the ability to fit themselves between DNA base pairs, which can lead to mutations (during replication) that, say affect the gene that encodes for the p53 protien, which can then lead to cancer.

The molecule you have pictured isn't flat by the way, the entire (penta? Should've paid more attention in ochem) ring sticks out of the page (or into depending on how you rotate it)


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Anonymous 18/11/23(Fri)09:26 No. 16725 ID: d40656

>>16723
Via intercalation, they're planer (flat) molocules and so they have the ability to fit themselves between DNA base pairs, which can lead to mutations (during replication) that, say affect the gene that encodes for the p53 protien, which can then lead to cancer.

The molecule you have pictured isn't flat by the way, the entire (penta? Should've paid more attention in ochem) ring sticks out of the page (or into depending on how you rotate it)


>>
Anonymous 18/11/23(Fri)09:28 No. 16726 ID: d40656

>>16723
Via intercalation, they're planer (flat) molocules and so they have the ability to fit themselves between DNA base pairs, which can lead to mutations (during replication) that, say affect the gene that encodes for the p53 protien, which can then lead to cancer. Agaent orange, or burnt BBQ are other fun examples for this.

The molecule you have pictured isn't flat by the way, the entire group attached to the benzene ring sticks out of the page (or into depending on how you rotate it)


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Anonymous 18/11/23(Fri)14:40 No. 16727 ID: be6f8f

>>16726
How does the molecule get there, though? I would have assumed DNA is separated from the rest of the rest of the cell by a barrier of some kind. Is the molecule tiny enough to pass through it?


>>
Anonymous 18/11/23(Fri)23:27 No. 16728 ID: d40656

>>16727
To enter the cell itself it depends, some are small enough to diffuse through the membrane, others may fit themselves between lipids (like chlostrol) then enter via endocytosis.

As for entering the nucleus, this is pretty much the limit of what I know (so take everything with a grain of salt), but general nuclear import requires a nuclear import signal to which a protein called importin will bind to and the resulting complex can freely pass through the nuclear pore complex. So as long as a nuclear import signal was attached your carcinogen can freely enter.


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Anonymous 18/11/24(Sat)22:19 No. 16729 ID: a132e4

>>16727
pores in a vertebrate's cell nucleus are approximately 120 nm


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Anonymous 18/11/26(Mon)17:09 No. 16731 ID: be6f8f

>>16728
>>16729
I see. Thanks.


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Anonymous 18/12/27(Thu)17:44 No. 16735 ID: 30e9be

>>16288
LOL!
Food can not cause cancer, this is a fantasy for morons!
Cancer is caused only by bacteria and viruses.


>>
Anonymous 18/12/28(Fri)17:15 No. 16736 ID: be6f8f

>>16735
>Food can not cause cancer
Well, artificial sweeteners are not food. They have no nutritional value.
On the other hand, heavy alcohol consumption can cause cirrhosis of the liver, which increases the risk of liver cancer.

>Cancer is caused only by bacteria and viruses.
What about things like ionizing radiation, or exposure to contaminants such as tobacco smoke, asbestos, etc.?
What about hereditary cancers?


>>
Anonymous 19/01/27(Sun)19:04 No. 16743 ID: c00a95

>>16736
Ionizing radiation does not cause cancer, but radiolysis, it is the accelerated decomposition of tissues, and not their degeneration in a structural form. Radiation can cause mutations in embryos, but it is not cancer.
Carcinogens and toxins are capable of causing cellular automaton breakdown, but for this, the body’s immunity must already be undermined by the introduction of viruses and bacteria, or by exposure to parasites.


>>
Anonymous 19/01/28(Mon)20:05 No. 16744 ID: be6f8f

>>16743
Radiolysis is the breakage of chemical bonds caused by exposure to high-energy particles. For example, such a breakage could happen inside an ADN molecule, causing its later copy to have an error. In other words, a mutation. Such a mutation can be cancerous.
Quoting Wikipedia:
>Exposure to ionizing radiation is known to increase the future incidence of cancer, particularly leukemia. The mechanism by which this occurs is well understood, but quantitative models predicting the level of risk remain controversial. The most widely accepted model posits that the incidence of cancers due to ionizing radiation increases linearly with effective radiation dose at a rate of 5.5% per sievert.[3] If the linear model is correct, then natural background radiation is the most hazardous source of radiation to general public health, followed by medical imaging as a close second.

When someone says "X causes cancer" or "X is a carcinogen", they're not saying "if you do X once you'll get cancer the following week". What they're saying is "X can increase the rate of mutations in your DNA, and a higher rate of mutations is a higher risk of cancer over time".

>Carcinogens and toxins are capable of causing cellular automaton breakdown, but for this, the body’s immunity must already be undermined by the introduction of viruses and bacteria, or by exposure to parasites.
That's not true. The immune system is capable of killing some mutated cells, but not necessarily every possible mutation. A typical infection can last what, a few weeks at most? Cancer lasts for months or years. If not having cancer was just a matter of having your immune system up to snuff, practically no one would ever get cancer.

Also, what a silly argument. If I see you wearing a helmet and then take it off, and while your head is uncovered I smack with a club, would you say that the cause of your headache is that you took your helmet off, and not that I hit you with a club?


>>
Anonymous 19/07/15(Mon)04:18 No. 16800 ID: 844136

>>16744
>If I see you wearing a helmet and then take it off, and while your head is uncovered I smack with a club, would you say that the cause of your headache is that you took your helmet off, and not that I hit you with a club?
If the helmet is a part of agreed protective uniform, such as in an ice hockey or cricket match, then yes, being hit in the head and dying would make the cause of death a failure to wear protective equipment. It's about what increases the danger/risk the most, not about which direct action was performed last.


>>
Anonymous 19/07/16(Tue)22:31 No. 16803 ID: be6f8f

>>16800
Firstly, cause of death in a medical sense (e.g. what gets put in a coroner's report) is the event that directly caused death. In the previous example, a coroner may write something like "cephalic hemorrhage caused by blunt trauma to the head".

Secondly, no. Protective equipment reduces your chances of injury, but doesn't eliminate them. If I hit you hard enough you can still die while wearing your helmet.
If you weren't wearing your helmet then we can't know if you would have lived by wearing it. All we know is that I hit and you died as a direct result.

Likewise, when people die while having cancer they died because they had cancer. Their immune systems may or may not have been compromised, but all we can say for sure is that whatever defenses they did have weren't capable of detecting and/or destroying the mutated cells.


>>
Anonymous 19/07/17(Wed)03:48 No. 16804 ID: 764277

>>16803
>Secondly, no. Protective equipment reduces your chances of injury, but doesn't eliminate them. If I hit you hard enough you can still die while wearing your helmet.
If you weren't wearing your helmet then we can't know if you would have lived by wearing it. All we know is that I hit and you died as a direct result.

Your an idiot. >>16800 is right. All those people who died in the 737 MAX crashes would have been fine if they had kept their seatbelts on and their trays in the upright and locked position.


>>
Anonymous 19/07/17(Wed)20:32 No. 16805 ID: be6f8f

>>16804
I can't tell if you're being sarcastic at me or at >>16800. Do we know that they weren't wearing their seatbelts and they died anyway?


>>
Anonymous 19/07/18(Thu)12:33 No. 16808 ID: 037764

>>16805
no idea what's going on with that post either.

anyway, the way I see it, assuming one is aware of the potentially fatal risks associated with the particular situation one is willing to put themselves in, as well as the available precautions/protections to greatly reduce the potential risk/damage, there's three stages to it:

1. the situation - you being present
2. the precaution - evaluating and minimising potential risk/damage
3. the result - clinical cause of death

assuming death occurs, one can say the cause of death is "carotid artery dissection caused by a blunt blah blah". focusing only on the direct cause of death dismisses the situation entirely and doesn't help in establishing the reason it may have happened in the first place.

being present in the situation can also be seen as the cause of death, although it is generally seen as a fallacy - "if being outside increases your chance of dying, why go outside?"

the main point i'm trying to get across, is in between the "situation" and the "death" stages. if i'm aware of the potential risk and through my own direct actions, or a lack thereof, i increase the risk/danger significantly or fail to minimise risk/danger significantly, then it is my fault i died.

same can be applied to, say, a man dying of AIDS. one can stick to the medical cause of death and that's all it will be, one man dead because of AIDS. one can look at the man's situation and find out he was gay and had gay sex - a fallacy, since far from everyone who has gay sex dies of AIDS. one can take an even closer look and find that the man has had over 100 sexual partners and has not used protection at least 70% of the time. this is an example of someone putting themselves in a high-risk and potentially fatal situation, while not taking the precautions they are presumably aware of. do you see my point yet?

apologies if this isn't relevant to the discussion you were having previously, I only ever meant to directly respond to your club2head analogy/hypothetical. i probably should have responded more directly to it, i.e. if i take my helmet off during a cricket match, a situation in which both of us are aware of the risks, then yes, taking off the helmet is the reason the headache/concussion happened. if i take my helmet off after said match and you throw a cricket ball at my head, then the reason i have a concussion isn't me taking my helmet off, since the particular situation i was in did not have an obvious risk of cricket balls hitting me in the head.


>>
Anonymous 19/07/19(Fri)05:03 No. 16811 ID: 5ae55e

>>16808
Of course, the club/helmet hypothetical is not a perfect analogy for cancer. Like I said before, cancer is a situation that develops over a long period of time. Cells accumulate copy errors that the body is unable to detect and correct or eliminate. Eventually that leads to a cell that loses apoptosis but not its replication capability.
In order for a weakened immune system to significantly increase the chances of cancer, it would need to be weakened for a very long time. If at any point during the development of cancer the immune system is active *and* it can detect those mutations (which isn't a certainty), it will destroy them.

So, a more appropriate analogy would be that I'm hitting your with a club once over a period of five years, and if you don't wear you helmet at all during the entirety of those five years, then at the end you're dead. If at any point you put your helmet on, your chances of dying are not negatively affected.
So yeah, if someone has AIDS or takes immunosuppressents for a long time, that would increase their risk of cancer a bit.


>>
bo 19/08/01(Thu)12:24 No. 16814 ID: 20d722

I found out I had bowel cancer about 6 inches in from the bum. I'm 73 . No one in my family history that I am aware of has had cancer of any type. It was said it takes 8 to 10 years to develop so I contracted it in say 2010.

Now the only thing the doctors say is "oh don't worry its not contagious" . In the next breath they will tell you "we don't know how cancer is caused".

WTF I got it from somewhere ! Roundup is a possibility perhaps but the so is any of the say 10 odd other chemicals I have used in and around my farming activities.

Possums in Melbourne carry around a flesh eating disease . I found a dead Bandicoot on my farm , it would have had 50 ticks on it a few were as big as my small fingernail. WTF


>>
Cancer bo 19/08/01(Thu)12:37 No. 16815 ID: 20d722

Trying to see where this is placed.
Guess you can't edit or modify posts.

Wanted to say " Take the bloody Governments free test". Supposedly it looks for blood in the stool only but I figured it was the coppers wanting DNA records to save themselves a ton of work finding perps. Still not sure whether they do or don't but having 6 inches of lower bowel cut out and 17 lymph nodes is not pleasant . I'm 2 months past that and can't get away from the shitter. Cant tell whether its coming down or not yet ,get about 30 seconds to run so I have a couple of pieces of toilet paper folded and wedged up there . Butt plug might work better. Its a shitty life now!


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Anonymous 19/08/01(Thu)21:00 No. 16816 ID: be6f8f

>>16814
>>16815
Man, that sucks. Cancer in any part of the GI tract is terrible.

>Now the only thing the doctors say is "oh don't worry its not contagious" . In the next breath they will tell you "we don't know how cancer is caused".
There is such a thing as negative knowledge; knowledge about a negation. Just because we don't know the causes of certain cancers doesn't mean we can't know that certain things definitely don't cause cancer. For example, we know that breathing water definitely doesn't cause cancer (it causes drowning).

The reason we know cancer is not transmissible is that the rate of cancer is uncorrelated with the amount of exposure to people with cancer, even when no special prophilactic measures are taken.
So, unless you've received an organ transplant from someone who had a genetic predisposition to cancer, no, cancer is not transmissible.


>>
Transmissible Cancer bo 19/08/03(Sat)07:33 No. 16817 ID: 679002

"The reason we know cancer is not transmissible is that the rate of cancer is uncorrelated with the amount of exposure to people with cancer, even when no special prophilactic measures are taken."
I have difficulty with that.
I used to be in Public Practice and shook probably 10 hands at least a day for 20 odd years. Now if just 1% of those people had a form of cancer I would never have known and certainly any statistical gatherers would never get the data to compare to anything.Repeat that in the world today with chemical exposures and microwave etc. and there is no valid data to back up a "not contageous" assumption


>>
Anonymous 19/08/04(Sun)10:55 No. 16821 ID: 5ae55e

>>16817
Oncologists are in unusually high contact with people who definitely have cancer, yet the rate of cancer among oncologists is not statistically significantly higher than among the general population.
Compare with cigarette smoke, where the rate of lung cancer is directly correlated to amount of exposure. Or ultraviolet radiation and skin cancer.

>there is no valid data to back up a "not contageous" assumption
How could you possibly prove that cancer is not contagious? We could rub someone with tumors all day, and if he doesn't get that type of cancer we could go "oh, maybe he didn't get it for such-and-such reason".
Instead, we need to find evidence that cancer is contagious. Well, people have tried to do that and they've failed.

I don't see why you lumped in contagiousness with chemicals. Some substances *have* been shown to increase the incidence of cancer. Smoke (particularly tobacco smoke), asbestos, benzene, etc.
Some forms of electromagnetic radiation have been shown to be carcinogenic, while others haven. In particular, shorter wavelengths than UV are ionizing, so they carry enough energy to break chemical bonds. Visible light and longer wavelengths (infrared, radio, microwaves, etc.) have not been shown to be carcinogenic.


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Anonymous 19/08/05(Mon)15:02 No. 16822 ID: 91237d

>>16289
>Cancer is caused by some kind of mechanism damaging the DNA of cells on contact, producing a random mutation.
That's like saying wounds are caused by insults.

It isn't even half of the actual story of what's going on, and leads to stupid statements like this >>16722
>Neither sweetener could even hypothetically act as carcinogen due to the mechanisms of how DNA is mutated.
Asbestos is silicate fibers, it has no chemical interaction with your body whatsoever, it causes cancer by purely MECHANICAL damage.

Cancer isn't just caused by mutagens for fucks sake, if that was the cause we would have cured cancer long ago.


>>
Anonymous 19/08/06(Tue)01:43 No. 16823 ID: 051d67

Cervical cancer turned out to be virus?
Stomach ulcers turned out to be a virus
Hepatitus C turned out to be a virus .
I'll guess it is all virus and transmissable we just hav'nt found out how yet.


>>
sage sage 20/05/07(Thu)04:04 No. 16916 ID: 628398

>>16822
> > Cancer is caused by some kind of mechanism damaging the DNA of cells on contact, producing a random mutation.
> That's like saying wounds are caused by insults.
No, it's more akin to saying wounds are caused by being clubbed.

> Cancer isn't just caused by mutagens for fucks sake, if that was the cause we would have cured cancer long ago.

Interesting conclusion, I was unaware we found a way to eliminate any possibility of mutations occurring.


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Anonymous 22/02/03(Thu)03:16 No. 18094 ID: a5935d

>>16823
Being caused by a virus isn't the same thing as being a virus.

The virus introduced mutations in the cells which - later - caused the cancer.

By inoculating against the virus you can prevent the mutations and therefore the cancer.


>>
Anonymous 22/02/10(Thu)20:11 No. 18105 ID: be6f8f

>>18094
I don't know if it's a virus, but some people's stupidity is definitely a disease, and we need some sterilization.



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