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Comment: Re:4-8 LITERS?! (Score 3, Insightful) 90

by quantumghost (#48020815) Attached to: Blood For Extra Credit Points Offer Raises Eyebrows In Test-Mad China

... 16.5 liters, or a bit over 4 gallons.

I got you beat. Last year I made my 80th donation, and was admitted into the ten gallon club. the Red Cross gave me a FREE T-SHIRT to prove it. Anyway, China has a big problem recruiting blood donors. There is a strong cultural taboo about losing blood. Even in America, where hospitals try to match patients with donors by ethnicity, there is a big shortage of Asian blood. My wife is Chinese, and she objected to me donating blood, insisting it would shorten my life, until I showed her that there was plenty of evidence that donating blood is good for you and may lengthen your life.

Ummm.... I work in a hospital and order blood fairly regularly for my patient population. There is no way to specify the "ethnicity" of blood. Blood is "typed" for major antigen (A,B,O) and "crossed" for minor antigen or factors (Rh, Duffy, Lewis, Kell, MNS, P, Hh, XK, Etc). Now, different "ethnicities" have different distributions of antigens which may make it more likely that someone of the same ethnicity matches, but no-one transfuses "ethnic-specific" blood.

And for the record the typical human has about 80 cc/kg of blood (e.g. the "mythical" 70 kg (154 lb) adult has about 5600mL (5.9qts ~1.5 gal) of blood).

Comment: Re:Wellcome to the common sense... (Score 1) 294

by quantumghost (#47937053) Attached to: Study Finds Link Between Artificial Sweeteners and Glucose Intolerance

Ever heard of emergent behavior? After "magical thinking" got debunked, it was failure to recognize that complex systems are not intuitively obvious in their behavior that needed to be overcome for medicine to progress to where it is now. This is also why data-mining is not sufficient evidence for medical journals....research should (almost has to be) double blinded, randomized clinical trials to sort through the noise and empirically test the complex system under study. Otherwise we would have developed a computer model long ago. This is also why we still have medical mysteries in this day and age.

I suspect, although can not prove it, that the artificial sweeteners trigger the pancreas to release insulin which will drop blood sugar (hypoglycemia) and increase the desire for sugar. I am drawing an analogy to the cephalic phase of gastric acid secretion

Comment: Re:Nerve control (Score 1) 26

by quantumghost (#47855205) Attached to: Scientists Regenerate Rat Muscle Tissue

That seems to be less than 1/2 of a solution. Nerve ending working in sync to create useful motion would be needed, no?

Partially correct. I was going to post saying that this was only half the solution for another reason.

A nerve needs to contact the muscle body which would allow control of the muscle, as a denervated muscle is mostly useless as it will atrophy away.

The other shoe that needs to drop is the fascial layer of the muscle. Without it the muscle is also useless. (Fascia is the tough fiberous out layer of the muscle that provides structural integrity and allows the muscle to function - think tendons. Without fascia a muscle is like a car without a frame - the muscle can contract, but has nothing to pull against). In traumtic injury, muscles can be damaged, but they have a pretty good regenerative ability, the fascia, which is much less cellular, is much tougher to fix....this, in a sense, why hernias are such a problem, its not a defect in the muscle, it's the fascia.

This may however be great for some musculodegenerative diseases like muscular dystrophy, but using the pt's own stem cells would not work...they're inherently defective. If you have a suitable donor, that was disease free, that might be a cure.

Regardless, this is a great accomplishment, hope they can build upon and improve this!

Comment: Re:No. (Score 1) 448

The story is a little deeper (at least some unofficial accounts):

The US sold Iran the F-14 (which in and of itself is supposed to be an interesting story), and after the fall of the Shah, the departing techs "bricked" the F-14 by disabling some of the physical avionics for fire control under the guise of a "software upgrade". The current F-14s are apparently resurrected by grafting some form of Soviet/Middle Eastern brand of missile that they had to reverse engineer. This did not happen overnight, and I'll bet the missiles they use today are still inferior to/barely equivalent the 1970/80s US tech they lost access to.

All I can find is this:

Was looking for a little more verbose description of the events that I read a few years ago. Still makes me crack up thinking about that story.

Comment: But is it even usable? (Score 5, Interesting) 208

So at 185TB per tape with the write speed of LTO6 "at speeds up to 400MB/s (1.4TB/hr)" [optimal]....~132 hrs per tape. But in reality 300 MB/s or 1 TB/hr so about 176 hr/tape. 168 hours in a week.....Next weekly back up starts before the first one finished.....

Yeah, I know, they're not all level 0 get the idea....sometimes it might be better to have 2 smaller tapes, than 1 large.

Comment: Re:Sucky Surgeon (Score 1) 56

by quantumghost (#46819255) Attached to: Closing Surgical Incisions With a Paintbrush and Nanoparticles

FWIW, silica nanoparticles have a GRAS certificate from the FDA and can be used in food products. Also, silica is chemically pretty stable at our body temperature and the only thing it can do is adsorb water.

Enteral (oral/GI administration) ingestion of a chemical is radically different then parenteral administration (through the skin or means other than through the GI tract). There are drugs that are safe one way, and deadly the other, and vice-versa. The human body is very fickle in that regards. Silica is very dangerous if inhaled.

In fact, I'm surprised that it even had the effect of binding the tissue together (maybe provided a porous network for the blood to come in through by capillary forces and coagulate? Your guess is probably better than mine).

It may initiate a wild, but localize inflammatory reaction. A concern then would be is it really _limited_? Widespread inflammation can be deadly.

That being said, the toxicity needs to be evaluated, but we can be optimistic.


The particles used in the experiment were super fine (only 50 nm in diameter) and synthesized using wet chemistry. Sigma Aldrich sells the LUDOX TM-50 that was used in the experiment readily in dispersion form at 28.30 EUR/L. This looks pretty scalable. If somewhat larger silica particles also exhibit the desired effects (i.e. if the glue effect is due to the high specific surface area, rather than the small particle size), then fumed silica can also be used which can be produced by the ton. The high temperatures of silica synthesis will also guarantee that the environment is pretty sterile (at least in the reactor, the engineers will "only" have to make sure that it stays that way until packaging, but it should be viable).

My problem is not with sterility. My problem is that most industrial chemical processes use heavy metals and other toxic substances as catalysts or intermediates....or that the intermediate steps that are difficult to eliminate may be toxic. This is why a pharmaceutical plant is vastly different from an industrial plant. The tolerance level is _much_ lower for pharmaceuticals. I tried looking up their analysis of LUDOX, but couldn't find it, the MSDS sheet did not list any minor components, but did list the silica as "chemically produced". I think you get my point.

Comment: Re:Sucky Surgeon (Score 5, Interesting) 56

by quantumghost (#46799211) Attached to: Closing Surgical Incisions With a Paintbrush and Nanoparticles

Is it just me, or does that guy really suck at suturing? I'm not a physician (never even played one), but I've watched instructional videos, and that didn't look like how the pros do it. The pros can suture and tie a knot way faster. If you suture like that then obviously glue would be better!

I felt really bad for whatever mammal that was (dog? rabbit?), especially because of the suturing job..

FWIW, the animal did appear to be adequately anesthetized as it did not flinch with the incision or suturing, and, no, he was not good, he barely knew what he was doing:
- wrong scalpel. That was a 10 blade used for long linear incision (e.g. > 10-40 mm). He should have used an 11 or 15 blade which are smaller and better suited to precision cuts, which these were not - he hacked at the skin instead if cleanly incising (so the technique was bad, the blade was dull, and he used the wrong blade).
- he did not use a pair of forceps to grasp the skin putting him self at risk of a needle-stick injury.
- needle entry was not perpendicular to the skin
- he used PDS suture (it looked purple) , which is _never_ used on skin (especially externalized). Prolene is used for an external knot, or vicryl or monocryl for a subcuticular suture
- the suture looks to be a 3-0 or 4-0....that's what I would use to close an adult human (5-0,which is smaller, for the face). Should probably be using 5-0 or 6-0 here. Then again, this guy would probably break that suture since he doesn't have the manual dexterity or technique. - he should have used a horizontal or 2 vertical mattress sutures to close the defect, not a single simple suture
- he didn't tie square knots and his tying was worse than a medical student's (who don't know how to suture either)
So I may just be nitpicking but, then again, that's what I do as an academic surgeon who trains upcoming surgeons.

But to actually address the article: It looks promising. I have questions about:
A) potential toxicity (nanoparticles can behave in less predictable way in-vivo) [large volumes of iron can be toxic to the body hemosiderin leading to iron overload], also silica is sometimes not well tolerated by the body
B) I would like to see this applied in a larger model (porcine would be good), with a large volume hemorrhage (analogous to a human GSW or stabbing wound) to see if the tensile strength of this seal scales up and to see if a large volume of blood will wash it away rendering it useless.
C) Does it withstand the detergent like properties of bile?
D) What percentage of normal tensile strength does this technique afford? Sutures physically hold tissue together to prevent separation under shear stress - how much strength does this stuff afford?
E) Does the substance affect normal wound healing (scar tissue is a normal, appropriate response, in an adult, to tissue injury; less scar may mean abnormal or poorer wound healing)
F) Will it be scalable (yes you can produce it in a lab easily enough, but can you make medical grade easily?)
G) Can it cause injury to adjoining tissue? The edge of the wound is hypoxic (low oxygen concentration), will this be toxic to these at risk tissues?

It is a long way from the lab to clinical use, but this appears promising. Look forward to seeing how the technology plays out. And won't put me out of a job, but if it works out it may make my job easier and give better outcomes.

Comment: Re:Scary (Score 1) 30

by quantumghost (#46446743) Attached to: LABONFOIL: A Portable Bond-Style Lab

If you'd ever had a colonoscopy, you'd really appreciate the non-invasive method of detecting colon cancer. It was mentioned in TFA, BTW.

Sorry, but this device ain't gonna fix that. As per their webpage they use a test for CEA as a marker for recurrence of cancer. This is not even an effective screening test, and nothing that isn't already available. Better get your prep ready, you're gonna get probed again!

Comment: Re:'Radiation Free' (Score 5, Interesting) 35

With tumors surely more traditional X-rays could only help matters (radiotherapy-lite)

Lol....nice try. External beam radiation therapy (XRT) ....varies depending on the type and stage of cancer being treated. For curative cases, the typical dose for a solid epithelial tumor ranges from 60 to 80 Gy, while lymphomas are treated with 20 to 40 Gy. Whereas a CT scan (the cardiac one being the highest dosing) tops out at 40-100 mGy or 2-3 orders of magnitude less.

In reference to the article, it is an interesting concept. Will need some work to improve its general applicability. By this the SFRP2 is only specific for colorectal and myelomas, so the technique is very limited. Also, please note that ultrasound is horrible to use around bowel, especially colon...the gas in the colon very effectively blocks the sound waves and you get very poor/incomplete images. Besides, colonoscopy is the gold standard for screening and has the advantage of being therapeutic or allowing tissue biopsies which can seal the diagnosis. Granted most need at least some sedation, but at 10 year intervals for most, this is a pretty acceptable tradeoff.

The only other question I have is the applicability....again, even if they can increase the scope of the detection, a full scan of the body for mets would be very unsatisfactory using if we start talking about sarcomas, renal cell, breast cancer, yeah, I could see this working out. Lung, brain, ENT cancers, not so much.

Comment: Re:not useless at all... (Score 1) 351

by quantumghost (#46037709) Attached to: Fighting the Flu May Hurt Those Around You

so since you have spread the infection for one day, before you were showing symptoms, you might as well go ahead and spread it for several more days afterwards?

horsehockey. one day worth of germs 3 days worth of germs.

stay at home when you are sick.

Didn't say that, reread it....

therefore you will not be able to ever stop the flu, at least not without a better vaccine (no, don't go pulling that Jenny McCarthy shit [] or I'll have to slap you); we can just mitigate some of the spread

I'm saying that you have already started passing the flu on, before you feel it. You can still mitigate it, but you won't ever get rid of it. The original poster does not know/understand the concepts of latency and incubation:

When you're sick enough to (feel you) need medication, stay at home.

My point was, it is already too late. Your best defense in not getting sick is to practice good hygiene, not relying on other people to stay home.

Comment: Re:So... (Score 4, Interesting) 351

by quantumghost (#46036355) Attached to: Fighting the Flu May Hurt Those Around You
I'll say that the outcome is hardly surprising. Nice to see some numbers attached, though.

When you're sick enough to (feel you) need medication, stay at home. Don't spread germs all over the workplace / auditorium / public mass transport.

Nice idea, but almost useless....

What this basically means is that you are infectious the day before you show symptoms.....therefore you will not be able to ever stop the flu, at least not without a better vaccine (no, don't go pulling that Jenny McCarthy shit or I'll have to slap you); we can just mitigate some of the spread. It is incumbent upon the uninfected to keep from getting infected, as those who are will not know they are until its too late.

The science is that fever is an adaptive response to an infection. Yes, fever is what makes you feel like crap, but it changes the kinetics of viral (and bacterial replication). Ever notice that microbiological (especially bacterial) incubators are set to 37 deg C? That's the sweet spot for replication....change it and you put the invader at a disadvantage. Modern medicine unfortunately has taken on the dogma that: "If it ain't right, it needs to be fixed", a few (and growing) are starting to learn that not all that is wrong is bad....I continually rally against treating fevers less than 40 deg C (above that is concern for brain injury), but I have an uphill fight against an entrenched culture.

My personal strategy? I take the anti-pyretics so i can sleep or function, but reintroduce the elevated temperature by bundling up and keeping my core above 37 deg C. This is not scientific, just what works for me, YMMV and I won't be held responsible if you up and die from the flu as this is not my official advice.

Comment: Re:Brought to you by (Score 2) 124

by quantumghost (#45478175) Attached to: New Smart Glasses Allow Nurses To See Veins Through Skin
This is not quite new....I've seen IR based devices over 8 years ago, I first saw this tech in 2005 and it was pretty mature at the time. I can't recall which company it was, but a quick google serarch shows this company has been doing something similar for 4 years. The article is grabbing headlines because they packaged it into a eye-glass format.

Comment: Re:Does the glasses pose any danger to the eyes ? (Score 3, Informative) 124

by quantumghost (#45478027) Attached to: New Smart Glasses Allow Nurses To See Veins Through Skin

From TFA:

That technology from Epson when applied to game, users do not put on those wearable display for hours and hours every single day, they only put them on when they play games.

On the other hand, nurses working in the hospitals may end up wearing the glasses which projects infrared lights many hours each days.

My question being --- Would prolonged exposure to infrared light poses any danger on the eyes of the wearer ?

Unlikely. IR light has a longer wavelength and thus less energy than normal "visible" light, this is why we can't see in the infrared - the photons are not energetic enough to cause a conformal change in one of the double bonds in rhodopsin. This also partial explains why we can't see in the UV spectrum. The only variable will be the intensity of the light potentially causing thermal damage, but I doubt this would be that powerful enough for that. In addition, starting IVs is not the only thing nurses do....I'd guestimate that it is only about 5% of their daily work load on the general med-surg floors (where most patients have an IV already) and probably no more than 10-15% of the ED RNs.

Comment: Re:I wish I could say this stage was unnecessary (Score 2) 99

by quantumghost (#45337365) Attached to: Robotic Surgery Complications Going Underreported

Now here's the robotic surgery any better, or offer benefit above, laparoscopic surgery?

Ultimately it will be since the entire purpose of inserting the robot in the process is to provide finer control and filter out accidental motions that could cause mistakes and complications with traditional, hands-on-the ends-of-sticks laparoscopy.

You would think that that might be the case. An engineer would think that way...I know I did when I was an engineer.

However, you are wrong. You don't understand how surgery is performed. For starters, this is more biology class than chemistry or physics....this is not a photoelectric cell where light above X wavelength will fail to excite the atom out its orbital to produce a current. This is 2 kg of fertilizer (plus or minus 200 g) will produce more robust flowers then 1 kg will. You are dealing with inherently unstable organisms that are extremely fault tolerant because the have to exist in a fault filled world.

The "finer control" is useless (I've seen older surgeons with a horrible tremor perform the most masterful procedures). We're not dividing cell layers, we're dividing tissue planes which usually start to tease apart with gentle traction. We rarely measure things out, and exacting measurements are never used (at least in abdominal surgery which is the vast majority of robotic cases are, cardiac cases usually use blanks to measure the fit of valves and neurosurgeons and ophthalmologists who arguably require the finest motor control do well without a robot and will likely never use one anyway). Say I find a tumor in the colon. I am required to resect back 5 cm on either side...but I will get equally good results at 6 cm, or 7cm. Hell, as long and I leave some of the colon, the patient will do well. A lot of what I do is dictated by where I see the many cases I have to remove the problem area, plus an extra margin. This is not a 2x4 where it has to fit in precisely, this is a piece of tissue with potentially unseen disease that requires an adequate margin of resection and a good blood supply to heal. In addition, I think you underrate the level of precision a bare surgeon's hands have, and overrate the about of tolerance the human body has.

Most complications are acts of omission not commission. Meaning, you did something without knowing it (using the electrocautery too long or not realizing that it was too close to another structure resulting in transfer of thermal injury). This type of problem will not - can not - be overcome with the robot. Other causes of complications include equipment malfunction or mis-use (such as a stapler failing), and ultimately poor surgical judgement. So basically, a robot adds nothing to reducing the complication rate, and rather adds a new level of complexity to the problem. Is that an improvement?

I spent two years looking into ways to use the precision of the robot to improve general surgery. Came up blank. We designed a few new attachments for it....but they mostly mimicked things that already existed for open surgery, or were needed to overcome some constraint imposed by the robot.

Right now it's use is limited by the number of approved procedures and the pack of wolves salivating at the prospect for waves of lawsuits against the manufacturer and operators. This limits the amount of data being produced to evaluate its effectiveness.

The only real future applications will be for tele-surgery, which with global travel being what it is, still hasn't reached any level of significance other than: "Hey we can do this!"

FORTRAN is a good example of a language which is easier to parse using ad hoc techniques. -- D. Gries [What's good about it? Ed.]