Readit Newspuzzlingcaptcha commented on RP2350 A4, RP2354, and a New Hacking Challenge raspberrypi.com/news/rp23... · Posted by u/geerlingguy
Raspberry Pi Foundation failing to communicate their development of this stepping will results in tens of thousands recently bought A2-stepping devices ending up in the landfill.
Do we have any studies that show this fast clearance? From what I understand at least one of them used a pseudo-uradine that there isn't an efficient direct metabolic pathway to process, which was kind of the whole point. The idea being it would circulate longer and be "more effective"
The uridine modification was intended to reduce immunogenicity of mRNA - some of our immune cells have pattern-seeking receptors in the TLR family that recognize ssRNA and dsRNA. The presence of modified uridines throws this pattern recognition off. (https://doi.org/10.1016/j.jconrel.2015.08.051)
The modifications to increase mRNA half-life concerned mostly the caps and poly(A) tail. But even with those the persistence was in the range of days (sort of depending on how sensitive a method you picked).
Interesting point there:
"The other problem is with viral vector based gene therapy is you can’t have it again. You develop antibodies which prevent it from working again, and it could cause a dangerous immune response."
Just wondering - would it make sense to immune-suppress the patient for a short period of administering of the viral-based therapy.
And as they describe that most gene therapies affect only extra-nuclear DNA, and thus have no permanent effect, wouldn't mRNA work better then in such cases - naturally the tech wasn't there 10+ years ago, yet today thanks to COVID it is here.
Edit (due to posting rate limit) in response to comment below:
I was thinking about mRNA coding dystrophin like it was coding COVID protein - should be cheap and easy (well, for some definition of easy in that context) doable, and it would be like a weekly self-injection - no toxicity, etc. Of course fixing the issue once for life would be better, once such cure becomes available, yet for now it would be similar like diabetics have with insulin - hassle for sure, yet it works.
AAV based therapies may have no permanent effect when the cells in question are actively proliferating (and the payload dilutes with each division) but muscle tissue is largely post-mitotic.
mRNA is in comparison very transient (in the range of days, and that's being charitable), even when modified (5' cap, uridine analogs, poly(A) tail) as it was in COVID vaccines. This is fine for vaccines, as you essentially want just a single exposure to the protein with each vaccine dose. You do need dystrophin continuously though (even though the cells are not dividing much, they are still recycling it).
You could argue for delivering gene therapy with mRNA/NLPs in multiple doses over the course of patient's life but that would likely 1) exacerbate toxicity and 2) be super-expensive
puzzlingcaptcha commented on What's going on with gene therapies? nehalslearnings.substack.... · Posted by u/nehal96
I am sorry you experience this disease. I have a question: You said "they do not change the nuclear DNA, they just insert copies of working genes into the cell ... The results aren’t carried through to new cells during division."
Isn't this a bit contradictory? I mean, if they insert copies of working genes into the cell, it is in nuclear DNA, so when the cells divide, the daughter cells carry the new gene?
I can imagine other cases, for example, progenitor cells were not infected, cells that do not divide, etc...
Thanks for any answer
AAV-based vectors are specifically non-integrating. Wild-type AAVs can integrate, but in the absence of rep protein they will instead persist in the cell nucleus in the form of episomal concatemers - long, circular DNA structures containing multiple copies of the virus DNA. These will not replicate when a cell proliferates - they will instead dilute with each division. This makes them desirable for treating diseases affecting post-mitotic tissue like muscle, less so for, say, bone marrow. Unless transient expression (but not as transient as with NLPs) is what you want.
Depending on what you’re doing, even for gpio. Just use a USB gpio board.
If you can do without SPI there's also https://www.adafruit.com/product/4471
You can also just get the chip (MCP2221A) in a DIP package and just pluck it in a breadboard. All you need is two bypass caps and two pullup resistors if you need I2C.
puzzlingcaptcha commented on The $25k car is going extinct? media.hubspot.com/why-the... · Posted by u/pseudolus
You can still buy a new subcompact car (like a Renault Clio or Skoda Fabia) in Europe for under 20k EUR.
The more interesting question is why these cars disappeared in the US. And while many of the factors discussed here are true for both EU and US (inflation, interest rates, manufacturer profit margins etc) I am surprised no one mentioned the 'SUV loophole' of US regulations that effectively boosted the SUVs (off-road vehicles are classified as non-passenger automobiles with everything that entails, notably much less stringent emission standards) and made the small cars unprofitable to make in comparison.
puzzlingcaptcha commented on The $25k car is going extinct? media.hubspot.com/why-the... · Posted by u/pseudolus
Almost all cars have turbos, all have abs/airbags/cameras... even counting the seat foam & covers, wheels, door cars... how cheap do you think a vehicle safe and comfortable for humans can be?
The average car has tons of moving parts that have to be weatherproof, shakeproof, pothole-ready... stuff consumer tech doesn't dream of. It also has to be repairable, be engineered to meet all the regulations in various countries so the manufacturer doesn't make 15 versions for different countries...
A lot of things are overpriced in the world; I'm not sure cars in general are high on this list. If you want a car similar to a high end 2015 car, the 2025 Jetta has more than anything you could have gotten in 2015 and I'd say with inflation the price is lower today when you account for inflation.
I had a Jetta as a service loaner recently and it drove great. $25k cars are still out there, you just can't get a $25k 4Runner.
Almost all cars have turbos since that's about the only way to get similar performance out a sub-1L three-cylinder engine that you could get from a cheap, naturally aspirated 1.6L iron block back in the 90's. Emission and safety standards are nice, but the customer pays for it.
200,000 revolutions per minute?
Boggles the mind that this is 3,333 revolutions per second.
I'm not saying you're wrong but a quick check of a few LLMs says that 90,000 RPM is widely cited as the practical upper limit for current operational centrifuges in facilities like those operated by Urenco, Rosatom, or Orano.
900m/s is approx Mach 1.5.
You can buy a lab centrifuge (such as Optima MAX from Coulter) that does 150 000 RPM, (or as a more useful measure, about a million g). These are often used for virus purification.
But isotope separation is usually done on UF6, which is a gas. These centrifuges work a bit differently, see https://en.wikipedia.org/wiki/Zippe-type_centrifuge
I remember last time I installed it, there was neither sudo nor doas preinstalled.
sudo was officially depreciated in 3.15 and moved to community in the next release https://gitlab.alpinelinux.org/alpine/tsc/-/issues/1