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Alfred001

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  1. I was shocked to find recently that there is apparently a lot of animal and some human data showing that antibiotics have a negative effect on male fertility. Given how serious this is, I couldn't believe this isn't more widely known and I was even more shocked at how little human data there is, again, given the seriousness. Does anyone know whether these effects are permanent? From the review I'm currently reading, it seems the effects usually last a long time post-treatment (weeks or months) and whether they are permanent or not is usually not answered due to how short the followup is. But certainly, the effects will usually still be present many weeks post-treatment.
  2. I see. Ok, let me ask a more specific question, and this is a really multifactorial one, so I know this might be tough to answer: I know that after a meal gastric pH rises due to buffering effect of food, now suppose you were to add dextrose on top of that, would you expect the addition of dextrose to affect the pH in either direction, bearing in mind the dextrose might be broken down by enzymes into, I think, maltose and fructose? And let's say no further gastric acid will be secreted, to simplify things.
  3. So a substance does not necessarily need to dissociate to affect the pH of a solution? But can lowering of pH happen only when dissociation happens (because the substance needs to donate a H)?
  4. Could you tell me whether my understanding here is correct: In order for something to affect the pH of a solution, it needs to dissociate. Non-electrolytes do not dissociate in water and would therefore not affect its pH. Would they, however, dissociate in gastric juice?
  5. But that's all we want to look at in this situation. Cancer. Not sure what you mean by this, but the experiment is set up to see whether people who take metro have more cancers than the people who don't, I don't see why that would be impossible to determine, provided an adequately large sample to factor out chance. I could have sworn that this is how it was explained in a number of youtube videos I watched on the topic! Ok, I definitely had a misconception about what a CI is. Nevertheless, that study still doesn't allow us to say whether there's an effect or not, right? The upper bounds of the CIs are 6+ and 2+, which means the effect could be of that magnitude.
  6. Ok, can you explain what you meant by that part? Doesn't the CI mean that the actual effect is somewhere in that range? If so, why is it then not more likely, since so much of the range is above 1 that there is an effect? In fact, the CI for the 12< year follow up group is 0.92-2.20 - almost entirely 1<. Can't we say there that an effect existing is significantly more likely than not existing, although it not existing (or a protective effect existing) is a possibility as well? Right, in other words, we cannot know from the study whether there's an effect. Why wouldn't it be if the effect is strong enough or the sample large enough? I mean the CI for the 12 year group is fairly narrow and almost entirely above 1. If you added some more pairs and narrowed the CI further maybe you'd get entirely above 1 and be sure that there's an effect. And to begin with, the CI could have been 2-3, if this were some other drug with a stronger effect.
  7. So it's actual incidence of cancer, divided by person years in the study and then multiplied by 100 000? I'm not sure what you mean by normalization. Why not just explain what you mean instead of getting petty? Ok, but the most we can say from this study, based on that CI, is that we don't know whether there is a greater risk in metro users, not that there isn't one, and in fact, given that the great majority of the interval lies above 1, it seems much more likely that there is one than that there isn't one, no?
  8. Yes, I understood that part. It's still the people getting the cancers. Doesn't change what's strange about it. I understood that as well, I'm not sure what you're getting at with this part. Yes, but that's what I'm asking, how is it possible to have as large a sample as they did and find as large an effect as they did and for it to be down to chance? 608 pairs in 15+ years and over twice as many cancers in the metro group, how could that be chance? Even if we accept their confidence interval, the value is 0.82-6.12. Most of the range of the interval covers a greater incidence of cancer by a factor of up to 6. At best, based on this, we can say it's unclear whether there is an effect and that the effect could be large (granted, also could be no effect), but we can't say there is no effect. Does anyone know how they would have calculated that CI and that p value? I mean in concrete terms, with these specific numbers. Point taken. When I said two papers, I was referring to what the Japanese study provided as references for their claim. However, the first study is talking about all ABs and different classes of ABs in aggregate. I would be interested in the safety data on the individual antibiotics that are used in H pylori therapy and therefore represent alternatives to metro for that indication. Those are clarithromycin, tetracycline, bismuth (I guess in some sense not an AB, but has the effect and used for the purpose), amoxicillin, levofloxacin and a few less commonly used ones such as moxifloxacin and doxycycline. The FDA issued a fairly stern warning for quinolones (levofloxacin, moxifloxacin...) in 2016. for some severe side effects, including potentially permanent ones, but I don't know how common those are. I don't know much about the safety profile of the other drugs, outside of penicillin allergy in connection with amoxicillin.
  9. I will respond to this as soon as I have the time to read the studies, but in the meantime, does anyone have the answer to these questions? I really want to understand that study.
  10. The claim about other ABs causing cancer is based on two studies alone. The nurse study and the clarithromycin study. The CLA study looked at all cause mortality, not cancer and median followup was 3 years, so you're not gonna detect any cancers with that. The epidemiological studies they reference lack data on dose and duration, so I don't know what the basis is for the claim about the safety of a short course of metro. EDIT: This is in response to Charon's post form the previous page.
  11. This paper critiques some of the studies used to arrive at the "no significant effect" conclusion in the earlier review: https://onlinelibrary.wiley.com/doi/abs/10.1111/hel.12575
  12. Prospects for clinical introduction of nitroimidazole antibiotics for the treatment of tuberculosis This paper provides an excellent review of the evidence. EDIT: Ok, they say later on in the paper that they think there is good evidence that it doesn't have a significant carcinogenic effect in man. Which isn't not to say there isn't one:
  13. That's almost exactly what I said in the VERY POST you were responding to. At this point I'm beginning to think you're trolling me. There's no way anyone can be this... I can't say what else I might get another warning. Like literally in the paragraph you're correcting me on I said virtually the exact same thing as your correction. And we would know about it, how? Again IN THE VERY POST YOU WERE RESPONDING TO I quoted what the paper said. Is there some way to make the font bigger? I'm afraid in the next post John will tell me, YEAH, BUT IF THE EFFECT WAS BIG WE WOULD KNOW ABOUT IT. Anyone wanna bet that's gonna be his next post? Yeah, if the effect was 100% we would know about it, great argument! Anyway, I'm done engaging with you. If anyone has an intelligent point to make on the topic or can bring actual evidence to the table like TheVat, I'm happy to continue this discussion. Hmm... why am I getting warned and not the guy who started the incivility? (literally his only contribution to the thread) Anyway, doesn't matter... Great find! This is, for a stark break from the norm, a valuable contribution to the thread. However, can someone explain what I'm not getting in this part: 1,336 and 564 cancers among users and non-users in at least 15 years of followup? Doesn't that mean there were 1900 cancers in 1219 people??? More cancers than people? I mean I know a person can get cancer multiple times, but THAT many multiple times? I doubt they counted recurrences as individual cancers and even if they did... Or am I completely misinterpreting things? Also, incidence of cancer in 15 years of CANCER-FREE followup... what? What am I not getting here? And then thirdly, 2.38x more cancer among metro users, how is that not significant? Ok, I see that the CI ranges from sub-1 to 6.12, but isn't that CI so wide as to be meaningless? And how likely is it that a 2.38x difference in 15 years is just down to chance??? Also, the limitations here are a bit worrisome, especially the absence of data on dose, duration and compliance.
  14. Seriously guys, is there a single person on this forum who can reason well? This point has been made ad nauseum by Charon alone, let alone all the other people who've brought it up. Like AD NAUSEUM. Yes, it's a cost benefit analysis. To make that cost benefit analysis, we need this: Understand? In other to make the cost benefit analysis you need to know what the cost is and what the benefit is. We know what the benefit is, but we don't know what the cost is. So I've asked Charon for a reference for his claim about the benefit being greater than the cost at least twice on this page alone and notice how he's ducked it both times, because he doesn't have it and he was just making a claim with no evidence for it. (love it when people debate in good faith!) Also, you're reprimanding me for name calling? Who started the uncivli behavior here? Me or the guy who jumps in with snarky comments, never contributes anything to the debate and then behaves immaturely when asked to back his snarky remarks up.
  15. If you're gonna talk shit then you should have the balls to debate and back it up, otherwise stfu punk. EDIT: Yeah, downvote my post, but UNDER NO CONDITIONS engage, pussy 😄 You know it wouldn't go well for you.
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