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CarbonRobot CarbonRobot
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Posts: 393
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A year ago
Do we know for sure that cartilage doesn't regenerate in humans? I assume we don't encounter the "wear and tear" of our joints unless we're an athlete or we reach late 20s or early 30s? Is it not safe to assume scientists typically don't experiment on younger people to see if they could regenerate certain tissues until a certain level of maturity? I have read the eye's lens can regenerate from present stem cells at age 2 or so. This tells me it might be a matter or signaling and the mechanisms of regeneration may exist for just about anything?
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Educator
A year ago
Cartilage is composed of specialized cells called chondrocytes surrounded by a gelatinous matrix of collagen. Cartilage lacks a sufficient vascular system that would otherwise allow blood and nutrients to saturate and enter the tissue. This is generally the accepted reason it cannot repair itself after injury. Thus, it is determined to have zero potential in adulthood of repair, but studies tell a different story in children and adolescents, who appear to have a greater capacity to regenerate cartilage defects. 

For example, in one study, they detected differences in in vitro analyses of cartilage tissue samples designated for secondary autologous chondrocyte implantation. The expression rates of the chondrocyte surface marker CD44, collagen type II, and aggrecan were significantly higher in patients under 20 years of age than in patients between the age of 20 and 50 years. The study suggests that chondrocytes from younger patients possess a reparative/chondrogenic potential that could lead to improved cartilage healing. But again, this is just an implication.
Source  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5858627
CarbonRobot Author
wrote...
A year ago
Cartilage is composed of specialized cells called chondrocytes surrounded by a gelatinous matrix of collagen. Cartilage lacks a sufficient vascular system that would otherwise allow blood and nutrients to saturate and enter the tissue. This is generally the accepted reason it cannot repair itself after injury. Thus, it is determined to have zero potential in adulthood of repair, but studies tell a different story in children and adolescents, who appear to have a greater capacity to regenerate cartilage defects. For example, in one study, they detected differences in in vitro analyses of cartilage tissue samples designated for secondary autologous chondrocyte implantation. The expression rates of the chondrocyte surface marker CD44, collagen type II, and aggrecan were significantly higher in patients under 20 years of age than in patients between the age of 20 and 50 years. The study suggests that chondrocytes from younger patients possess a reparative/chondrogenic potential that could lead to improved cartilage healing. But again, this is just an implication.

Well it's something. My back hurts all the time. People weren't meant to live past 27. I am increasingly certain of it. Curt Cubain, Jesus, Bruce Lee. They all got out at the right times. I am nauseous all day everyday for the last year now, and an anticonvulsant is the only reason it is less violent. This hasn't been life.
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Educator
A year ago
I actually disagree with that idea, that people wouldn't live past 40. Jesus was crucified, he didn't die of natural causes, so that example is far from true.
CarbonRobot Author
wrote...
A year ago
I actually disagree with that idea, that people wouldn't live past 40. Jesus was crucified, he didn't die of natural causes, so that example is far from true.

None of them died of natural causes, but at least Jesus invited it.
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Educator
A year ago
What do you mean?
CarbonRobot Author
wrote...
A year ago
What do you mean?

He elected to be arrested. He had the option to leave town. Some have even said he instructed Juddas to turn on him.

In any event people are encouraged to write a will in their late 30s to 40s versus 80s.
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Educator
A year ago
I don't think Christ had a choice in his arrest. He was summoned to be arrested by the Jewish leaders of that time. Scripture tells us that Judas sold Christ's whereabouts for silver coins; they still would have found him otherwise. It wasn't in Christ's character to run away from legal orders.

Anyway, let's focus on this statement - I like the direction its heading.

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In any event people are encouraged to write a will in their late 30s to 40s versus 80s.

We can easily admit that life was a lot harder before modern day technology, sewer systems, electricity, etc. But, we must also consider that foods were arguably healthier, didn't contain additives, industrial sludge, or artificial fats. What was hunted needed to be preserved with salts, or eaten within days. From that standpoint, I'm certain nobody died of diabetes or heart disease.
CarbonRobot Author
wrote...
A year ago
I don't think Christ had a choice in his arrest. He was summoned to be arrested by the Jewish leaders of that time. Scripture tells us that Judas sold Christ's whereabouts for silver coins; they still would have found him otherwise. It wasn't in Christ's character to run away from legal orders. Anyway, let's focus on this statement - I like the direction its heading.
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In any event people are encouraged to write a will in their late 30s to 40s versus 80s.
We can easily admit that life was a lot harder before modern day technology, sewer systems, electricity, etc. But, we must also consider that foods were arguably healthier, didn't contain additives, industrial sludge, or artificial fats. What was hunted needed to be preserved with salts, or eaten within days. From that standpoint, I'm certain nobody died of diabetes or heart disease.

Certainly food quality has declined. I think Sadguru has said on the Rogan show (not a regular listener) that one major issue is farms that grow one crop that completely depletes the soil.

My argument is more to do with our development stopping at age 25 or so. So we're basically in free fall from there. Most people's eye lenses start hardening after 40 if not a little sooner. I read something like a factor of five in its change in flexibility for focusing. The changes can be very dramatic. And the term "dad body" referring to getting chubby after having kids. Technically our metabolism doesn't slow until after 60, but people certainly tend to lose firm shape after 30. I believe it's the body's decreases in feedback to the brain. We lose sense of hunger and the specific effect of the specific food items. This ability is important. I used to feel lots of energy from a strawberry. I feel just about nothing from a doughnut now. If we aren't advancing biological than we have to be declining.
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Educator
A year ago
Certainly food quality has declined. I think Sadguru has said on the Rogan show (not a regular listener) that one major issue is farms that grow one crop that completely depletes the soil.

How would a monoculture deplete soil nutrients? Wouldn't it be the same for any farm? That is, every year the soil needs replenishment regardless of what's grown.

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If we aren't advancing biological than we have to be declining.

Absolutely. Once I reached my 30s, I found doughnuts and fast food burgers less palatable. Heck, the beef patties found in Burger King and McDonald's sandwiches barely contain any meat. They're thin, full of fat, and cheap. Krispy Kreme doughnuts barely classify as food.



* For every real ingredient, there are 2 artificially manufactured ingredients. And we wonder why our eye health degenerates, and how the "dad bod" evolved.
CarbonRobot Author
wrote...
A year ago
I don't know much about farming, but I figured one crop may leave a byproduct of its production that may provide something another crop can use to grow? I know in the fridge different produce should be put together because one may release a gas that helps preserve the other. Different organisms can balance each other out?
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Educator
A year ago Edited: A year ago, bio_man
The most I ever got out of why monocultures are "bad" was in reference to biodiversity, in the sense that it decreases biodiversity. In addition, it increases the risk of disease and pest outbreaks because they lack other plant and animal species that limit the spread of disease and control pests through predation.

Most sources online will tell you:

Growing the same crop year after year reduces the availability of certain nutrients and degrades the soil. Monocultures may therefore also lead to soil exhaustion when the soil becomes depleted of these nutrients.

But I don't know how this conclusion was derived. Perhaps some crops require a lot more nutrients to grow each year than others. And thus by sharing the soil with other crops, fewer fertilizers are needed? Again, this logic doesn't sit well with me.
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