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Evidence of the body’s waste system in the human brain

nih.gov

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Re: Evidence of the body’s waste system in the human brain

#61

Post by autokad »

blubb-fish wrote: post #33
Boothroid wrote: post #31

Earlier quoted context omitted.

I wonder the same thing. Not to be snarky, but is there something faulty about medics or human biologists?! Why do I have a feeling that if we deployed computer scientists at medical research we would get a better result? I can accept that at the lower level things get fiendishly complex, but surely at a macro level like this it's just a case of diligent analysis?

Most professionals in the field of medicine were educated towards an elitist and dogmatic mindset. When I talk with a physician about the human body I always get the impression they really believe the body works as described in the books - exactly like that. Most of them didn't seem to have noticed or learned that what we know about medicine is just theory approximating reality and all of those theories had to be upd…

one time i got a sore throat and fevor, the fevor wouldnt break for 7 days. the entire time i could feel the spot where my sickness was coming from. i looked in a mirror and there were puss modules - classic strep throat. I go to the doctor, she does the strep test and it comes back negative, she refuses to prescribe me antibiotics and told me to just go home and rest.

luckily, i had a penicillin script that I didnt finish, and after the first pill the sore throat (and the fever) broke within hours.

later when talking to my brother (who is a doctor), he told me the problem, one that he had also. When he gave the step test, it came back negative even when he knew it was positive. an older attending told him that you have to really get it in there, rub it around for a long time in order for it to work, where most just do a quick swipe.

another such example was someone came to the ER with chest pain. they didnt detect anything in the blood test so they were going to send him home. my brother refused and ordered more tests. turns out he was in the middle of having a heart attack when they were going to send him home, because ... the test.

the moral to the story is, many doctors blindly rely on tests and whats in the book, and disregard contradicting evidence.

Re: Evidence of the body’s waste system in the human brain

#62

Post by zellyn »

etiam wrote: post #35
mysterypie wrote: post #29

> the team discovered lymphatic vessels in the dura, the leathery outer coating of the brain Can someone explain why these vessels were never discovered during autopsies until now? Are they too thin, or transparent, or thought to have been something else, or the tubes become squished after death and therefore difficult to separate from other tissue, or what?

Kipnis made a mention of this in an interview closer to the actual discovery: As to how the brain’s lymphatic vessels managed to escape notice all this time, Kipnis described them as “very well hidden” and noted that they follow a major blood vessel down into the sinuses, an area difficult to image. “It’s so close to the blood vessel, you just miss it,” he said. “If you don’t know what you’re after, you just miss it.…

The "they're really close to the blood vessels; you could easily miss them" answers don't make sense. Surely any time you do brain surgery in the area beside those blood vessels, you'd be studying the area minutely?

Re: Evidence of the body’s waste system in the human brain

#63

Post by efficax »

lr4444lr wrote: post #41
etiam wrote: post #35

Earlier quoted context omitted.

Kipnis made a mention of this in an interview closer to the actual discovery: As to how the brain’s lymphatic vessels managed to escape notice all this time, Kipnis described them as “very well hidden” and noted that they follow a major blood vessel down into the sinuses, an area difficult to image. “It’s so close to the blood vessel, you just miss it,” he said. “If you don’t know what you’re after, you just miss it.…

Then what of the Italian scientist who noted them 200 years ago? All of those dissections and attention to research in the modern age and it was actually taught in medical school that the brain had no lymphatic system? Seems a little far-fetched.

We still have a very poor understanding of the body. We're still discovering organs we didn't know we had: https://theoutline.com/post/851/scientists-identify-new-orga...

It's entirely plausible to me that this has gone unnoticed for 200 years.

Re: Evidence of the body’s waste system in the human brain

#65

Post by dom0 »

adaml_623 wrote: post #60
etiam wrote: post #17

At first I was incredulous that they would make this claim, since it makes it appear they either failed to follow the literature enough to notice other researchers made the remarkable discovery of this system three years ago, or are trying history revisionism to claim that discovery as their own. But I guess the operative word here is "human". The original research actually gets a small mention in the text body. Anot…

I would be helpful to supply a link to the research from 3 years ago that you are mentioning.

https://en.wikipedia.org/wiki/Meningeal_lymphatic_vessels

> While it was initially believed that both the brain and meninges were devoid of lymphatic vasculature, a recent study by Antoine Louveau and Jonathan Kipnis at the University of Virginia, submitted in October 2014, and another confirming the discovery, by Aleksanteri Aspelund and Kari Alitalo at the University of Helsinki submitted in December 2014, identified and described the basic biology of the meningeal lymphatics using a combination of histological, live-imaging, and genetic tools.

I'm not sure whether these are the same entities?

Re: Evidence of the body’s waste system in the human brain

#66

Post by efficax »

wiz21c wrote: post #19

Can this mean that if one has a lot of stress, then its brain makes a lot of waste which pollute the lymph and thus affects the immune system ? ('cos it's well known that stressed people get sick quicker)

One thing this does seem to suggest is an explanation of why exercise encourages brain health. The lymphatic system only circulates well when the body is in movement, so exercise would help the lymphatic fluid circulate through the brain and thus help "clean" it.

Re: Evidence of the body’s waste system in the human brain

#67

Post by jerf »

lr4444lr wrote: post #41
etiam wrote: post #35

Earlier quoted context omitted.

Kipnis made a mention of this in an interview closer to the actual discovery: As to how the brain’s lymphatic vessels managed to escape notice all this time, Kipnis described them as “very well hidden” and noted that they follow a major blood vessel down into the sinuses, an area difficult to image. “It’s so close to the blood vessel, you just miss it,” he said. “If you don’t know what you’re after, you just miss it.…

Then what of the Italian scientist who noted them 200 years ago? All of those dissections and attention to research in the modern age and it was actually taught in medical school that the brain had no lymphatic system? Seems a little far-fetched.

"Then what of the Italian scientist who noted them 200 years ago?"

Two possibilities come to mind. First, he may have been studying a rare brain that had an enlarged system, and since he did not have preconceptions that what he found couldn't possibly be a component of the lymphatic system, he called it like he saw it. (It is also possible such brains were less rare back then or something. Many things have changed in our body's environments in the last 200 years. Random correlations abound.)

The other is that perhaps he was simply wrong. He saw something that he identified as a lymphatic component but was in fact something else. Future people didn't make the same mistake so the observation sank without a trace. 200 years later, the real and much-more-subtle lymphatic system was found.

Re: Evidence of the body’s waste system in the human brain

#68

Post by NamTaf »

zellyn wrote: post #62
etiam wrote: post #35

Earlier quoted context omitted.

Kipnis made a mention of this in an interview closer to the actual discovery: As to how the brain’s lymphatic vessels managed to escape notice all this time, Kipnis described them as “very well hidden” and noted that they follow a major blood vessel down into the sinuses, an area difficult to image. “It’s so close to the blood vessel, you just miss it,” he said. “If you don’t know what you’re after, you just miss it.…

The "they're really close to the blood vessels; you could easily miss them" answers don't make sense. Surely any time you do brain surgery in the area beside those blood vessels, you'd be studying the area minutely?

Anatomy textbooks aren't anything like real life. They're all colourful, clearly distinguished and clearly labelled, yet any autopsy will reveal a mess of reddish brown that tangles and squishes together. Also remember that human bodies aren't constructed, they're grown, so the idealised version of the textbook isn't what you end up seeing when you cut something open, and what you see when you do that changes each time you do that. It's why cadavers are still used to teach medical students.

Re: Evidence of the body’s waste system in the human brain

#69

Post by amelius »

kensai wrote: post #24

This one, together with the original rodent observation in 2015, is one of the few "macroscopic" observations in anatomy the last decades. Since most of the details of human and higher mammal anatomy have already been described, it is rather rare and outstanding to make such new, remarkable observations. PS: I work in an Anatomy Department.

I'm not a biologist, but can't this type of discovery be made by doing e.g. RNA-Seq analysis of cells in different parts of the body? I can imagine that every type of cell has a unique fingerprint, and lymphatic cells would be easily identified when sampled in the brain this way.
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