Operation Frankenweenie

Let's say that tomorrow, a heartbroken billionaire comes to me with a desperate problem. His beloved elephant, Jumbo, died just ten minutes ago. The massive team of the world's best biotechnology experts tell him that death is permanent, and he should accept this, but he'd given anything to get his elephant back. Sane science has denied him, so now he's turned to me to try something psychotic. And of course, I agree.

The process would be upsetting to watch, being a surgery and all, so we tell him to do his job, while I and his team do ours. I tell the biomedical team to separate Jumbo's various organ systems, and put them into vats of saline to halt the decay. I then review the situation.

All death is brain death primarily. Your body fails to provide the glucose and oxygen that your neurons need, which makes them fail, the way that a hammer strike to the motherboard takes out a computer. If my heart were to abruptly fail while I was in a hospital, the doctors could save my life by immediately hooking me to a cardiopulmonary bypass machine, and find some sort of replacement heart, such as one donated by a person who is too dead to need it anymore, or perhaps a mechanical replacement. Same for my lungs. My digestive system could be replaced by a nutrient IV drip, and my kidneys and bladder by dialysis. However, without a working brain, that's pretty much the end of me. So to fix the whole death situation, I'm going to repair Jumbo's brain. First, a review of the medical team's technology.

I order a cardiopulmonary bypass system and a saline-and-glucose IV for each of the organ systems, and a virtual reality system to keep the brain sane as I repair it. I then use the medical team's deep scanners to record the neuron patterns of which cell are connected to which cell, which is written to the massive RAID array. This takes countless exabytes of data, but I'm not footing the bill on this.

Next, a sample of Jumbo's DNA is taken from his muscle cells, and used to make a huge vat of stem cells. I write a program to check the brain records in the array, and one by one replace the dead neuron with a stem cell. The cell is influenced into becoming a neuron cell, and the program then tries to force it to make the connections that it's predecessor had. This automated process is replacing a hundred thousand cells per second, but will still take several months to complete. I have the VR system keep this growing brain in a delta-wave state -- deep sleep. The IV system is feeding it the nutrition that it needs to survive, the cardiopulmonary bypass system is keeping blood circulating, and the dialysis machine is purifying the waste. When the process is done, a disembodied Jumbo brain will be floating in the tank.

However, since our billionaire donor expects to be able to interact with his pet outside of VR, we will now have to repair the rest of the body as well. This is somewhat simpler. We dissolve the cells from each of Jumbo's organs, then leave the extracellular matrix in a vat of stem cells. These quickly repair into organs, which we keep alive in vats with a cardiopulmonary bypass and a dialysis machine keeping them individually alive and functional. It is here that I learn Jumbo's cause of death -- his heart developed a clot, starving the rest of his body of food and oxygen. Jumbo had died of a heart attack.

I have to periodically monitor the brain's progress. Three months in, the brain is 75% repaired. I adjust the VR system to move from delta, up to gamma, to nearly beta, then back down again, just as in real sleep. Jumbo's brain will now "dream," keeping it healthy.

We then work to recombine Jumbo's organs and muscle systems, minus the skull. This allows us to simplify the life support system, and sell off about half of the equipment. It will also give Jumbo a head start on healing, and at this point he's stitched together like Dr. Frankeinstein's monster. I can now report to our sponsor that Jumbo is alive, mostly. Cold hand of death, release him! However, he will need another six months before he can play with his master again. Our billionaire is tearfully grateful. A month later, I allow the VR system to bring the brain periodically to full beta, allowing Jumbo to "wake." I have programmed a virtual environment of a grassy field with fruit trees, and monitor how Jumbo navigates this environment. Mostly, I want to see that this experience has not rendered him insane or traumatized. So far so good.

Three months later, we need to reattach the brain. We slip the brain into the skull while still in the tank, then I have the surgeons reattach the skull to the rest of the elephant. The blood vessels and nerves are very carefully moved from the cardiopulmonary bypass and other life support machines to the elephant body.

Jumbo is now quite obviously alive, but paralyzed and sore. We keep up a medical treatment of intervenous feeding, and nerve repairing blue dye. It is now for the first time in seven months that our sponsor has seen his pet. At this time, I've done all I can do.

Five months later, I get a postcard from our sponsor. He's playing with Jumbo, who is now biologically a young adult. Jumbo has a renewed vigor, and a zest for life that our sponsor finds deeply inspiring. The biology team has him on a treatment for his blood condition, and Jumbo will easily outlive his master this time around. And I? My research paper on reversing death itself has led to a nomination for the Nobel prize in medicine. I must share credit for this with the biomedical team, but honestly, I'd rather that they take all the credit. Fame is not for me when mad science is on the line.

Curing AIDS

Since it first appeared in America in 1985, there has been an intensive amount of interest in a treatment of some sort of the Auto ImmunoDeficiency Syndrome, or AIDS.   Other countries may have been interested when first exposed as well.  And according to Slashdot, we may now have it.   Supposedly, 3 people have been completely cured of the disease, which was previously minimally treatable and guaranteed fatal.
This is still tentative and prone to additional testing, since case #1 apparently has some radical differences with cases #2 and 3, covered in the article.   The theory relies upon bone-marrow transfer immunity.   When you receive a bone-marrow transplant, you inherit with it the donors immune system capabilities, including all vaccinations.   In this case, one of the rare people who was completely immune to AIDS (for genetic reasons mostly) donated bone marrow to these two patients, who inherited the immunity. 
If this can be confirmed, this will mean a radical new hope for the world's suffering.  Still no cure for the common cold or herpes, though.

Heart Jellyfish

Via Slashdot, I have learned of the world's first artificial animal -- a jellyfish made of plastic and rat heart cells.   The benefits are surprising and unexpected.
This jellyfish like thing starts to "swim" when exposed to electric currents, just as hearts beat in time to electric currents.   Put this thing in a tank of sugar water and attach a pacemaker, and you have the perfect environment for testing heart drugs.
Traditionally, heart drugs had to be tested by breeding rats with sick hearts, injecting some rats with the drug and some with a placebo (saline solution to make sure that results aren't just some weird side effect of injections in general), and noting their recovery or death.  Then human clinical trials were required because rats don't respond quite the same as humans.  (Doing the original testing with humans would be condemning some humans to die, which people won't put up with.) All of this was expensive and took a lot of time.
So instead, we could make a human heart cell jellyfish, put it in the tank, and expose it to drugs dissolved in the water.   The effects of the drug become apparently relatively quickly, suggesting which drugs, if any, are good candidates for a successful clinical trial.
The rat version?  Proof of concept.

Bodyswaps

A common element in fiction is to have two characters exchange bodies. Guy A and Guy B swap, so now Guy A's body has Guy B's personality and mind, and Guy B's body has Guy A's personality and mind. How does this happen? It's hand waved away as inexplicable magic, usually, and the plot usually revolves around developing a greater respect for each other, with various comedic misunderstandings along the way, as no one seems to recognize the abrupt changes in behavior and knowledge, or any of the other clues that this has happened. Sometime before the end of the story, they get to swap back. The closest real life version of this is a brain transplant, or more pedantically, a body transplant. After millions of attempts, we finally succeeded with monkeys, transferring the brain of one monkey into another, and vice versa. This was significantly harder than it sounded, mostly due to the difficulties in reconnecting the nerves, and both monkeys were thereafter paralyzed below the neck for the rest of their lives due to the insufficient reconnection of nerves. But what if there was a cheap, reversible, reliable, consequence free means of completely seizing another person's body, which most realistically will be done by putting your brain in their skull and reconnecting every single nerve. (Again, way harder than it sounds. Especially because a living brain is about the consistency of a raw egg yolk, and every severed nerve is basically going to stay severed forever.) I'm imagining that this actually has commercial potential for a lot of people. A body builder and I go down to the transplant center, and we swap bodies. I am now a muscular 25 year old man, and he is now a 31 year old fat bespectacled nerdy man. We also have to register this for security and legal purposes, which I will get into later. Surprisingly, we can both get something out of this. My benefit is more obviously immediate. I'm no longer fat, I can run for miles at a time, I have huge muscles and the strength to lift small cars, or at least motorcycles. I can easily climb the stairs to the top of my workplace without breaking a sweat. However, on the downside, our bodybuilder has also heavily into steroids. This has taken a major toll on his body, and he can no longer work out, his favorite pastime, without breaking his arms. He also may have developed hormonal issues, which can lead to such strange issues and gynecomastia, in which he's developed a case of awkward, teen-esque breasts (likely misshapen) and will need to wear a bra. His body has bizarre pimples and random hair growth from a case of puberty that eternally mutates into a worse version. His genitals no longer function, much to the annoyance of him and anyone he's seeing romantically. Since I had neither the inclination to use steroids, nor the knowledge of where to find them, my body does not have these issues. For him, he regains the ability to work out, and while we should probably remain celibate for the duration lest we cause extremely awkward feelings with our respective loves, he can enjoy some alone time, if you know what I mean. I will also care similarly for his body, and while he'll lose muscle mass and probably gain weight, I won't do steroids, and his body will become more fit for exercise over time, and his hormonal issues will subside as his body, under my control, returns to equilibrium. Under my direction, his body will repair injured muscles as well. He will have significantly better gains when he regains it. With my body, he'll have to start over from scratch, exercise wise, but his exercise hobby will lead to him pushing it quite hard. I anticipate easily losing 10 to 20 pounds from his anaerobic exercise alone, and that's assuming that he doesn't also do cardio exercises such as bicycling, swimming, and other sports popular with weightlifters. We'll remain swapped for two weeks to a month. When we trade back, his body is weaker than before the swap, but still very muscular and strong, fully repaired, fed a balanced diet, and ready for some seriously awesome exercise. His hormonal issues are gone, which his girlfriend will surely appreciate. After just two weeks of exercise (which will be both fun and easy for him), he will be able to show off his body proudly, and people will be able to enjoy looking at it. For me, under his direction, my body has lost weight, and gained serious muscle mass. If he hasn't done steroids while using my body, then my body is now looking quite nice. If he has, then I can treat it the way I treated his body, and the issues will fade. I look quite nice, and my girlfriend will surely appreciate it. I imagine other people will also quite cheerfully swap bodies to handle mutual issues. A cancer patient who can't keep weight down can swap bodies with an obese gourmand. A person who loves a food they are allergic to swaps bodies with someone who has no allergies, but doesn't like that food. (or could live without it.) A person who's too ill to leave the house swaps bodies with a shut-in who didn't want to leave the house in the first place. All sorts of benefits could happen. However, on the security angle, this would have to be tightly controlled. Say I, in a fit of nefariousness, swap bodies with a hobo, and use the hobo's body to commit lots and lots of crime. After the end of my crime spree, I then swap back and leave the country. The police swiftly arrest the hobo, who was seen on camera robbing banks, breaking into houses and stealing from them, punching people that I didn't like, and other highly illegal things. If he's particularly illucid or incoherent, he'll find it quite impossible to defend himself, and spend years and years and years behind bars for my evil deeds. I meanwhile live off my ill gotten gains where they'll never find me. The only way I could be caught would be if there was a record of the body swaps, showing that I was the actual identity of the man on camera committing all that crime. They would also have to catch me before I left the jurisdiction in favor of one with no extradition treaty. There's also the issue of property. The hobo now looks like the man in my wallet, and unless my wallet is taken out of my pants and moved to the hobos at the time of the surgery, he could very easily take it and my credit cards to whatever store he felt like, and I'd have a real hard time arguing that it wasn't me. Of course, Neurology is currently way too primitive to pull this off yet, so this is all moot, at least within my lifetime. The possibilities are truly crazy.

Neurotransmitter Drugs

Caffeine is a commonly used substance in my workplace. It is a stimulant drug that works in humans by interfering with the neurotransmitter adenosine, as illustrated by The Oatmeal Plants that make caffeine do so to retaliate against the insects that eat them. The bugs get overstimulated and panic themselves to death. There are many other mechanisms that could be interfered with. For example, seratonin. Blocking seratonin would interfere with the pleasure of hobbies and activities, but also addiction. Under the influence of seratonin blocking drugs, a person would not be motivated to seek out their addictions. Maybe instead they'd have a nap. Four months later, the drugs are discontinued, and the patient is encouraged to take up a hobby, which is now fun. Other mechanisms could cure anxiety disorders, weight control issues, impulsivity, and a host of other quality-of-life problems.

Artificial Immune System

Many simple lifeforms see our body as a plentiful sack of resources -- bacteria desire our proteins, carbohydrates, and iron and viruses seek to turn our cells into viral factories. Since these thefts hurt us and can even kill us, we have developed immune systems that destroy these on "sight," along with malfunctioning cells a la cancer.
While our immune system is strong, we benefit from helping it out, especiallyin medical situations where all tools must be absolutely sterile. Our existing plans for this involve high pressure steam, which heats the tool to temperatures that denature the bacteria and virus's proteins so that they cannot survive. We also have chemical attacks such as alcohols that have the same effect. This is also required to a lesser degree in other fields like restaurants, in which it would be bad if a client caught a disease from another.
Suppose one made a nanobot that dismantles known bacteria and viral proteins and uses them as raw materials to make additional nanobots. If one kept tools in this environment, the tool would stay sterile for cheap. (Presumably there is a means to prevent the nanobots from escaping, such as requiring them to stay within a power field not provided outside the toolbox.) In addition, if these nanobots could be taught not to attack human cells, and could be powered in a human body, then this would restore immune function to the immunocompromised. This would greatly increase their quality of life. In addition, immunocompromising diseases attack immune cells through attachments to their cell membrane. These nano-immune system devices do not have one of those.

Printing a brain

Printed organs offer a major step towards immortality. I could take one cell from each of my organs, and use it to grow a brand new spare. I would then be guaranteed a very long life indeed, because disease or damage could be repaired fairly quickly by swapping my organs. Arteriosclerosis? New heart, no problem. Lung virus? New lungs. Cirrhosis? New liver. There'd be no chance of rejection, because they're grown from my own cells, and the cost would rapidly reduce over time from an economy of scale. However, if I had a stroke, or brain damage due to concussion, or became demented, I couldn't exactly swap out my brain. Or could I?
While if my brain were directly swapped out entirely, I would definitely be a different person, suppose only a small amount were changed at any given time. Starting with the moment that my doctor suspects that I'm developing a brain condition, I have a small amount of my brain biopsied and replaced with a printed copy of that section. This is allowed to heal and integrate back into my brain. Then a section a few inches further is biopsied and replaced, and over the course of about five years or so, every single piece is replaced. During the healing time, the neurons reestablish their connections, so at no point do I lose psychological continuity. And when the replacing is done, I have the brain of a twenty year old. If this works, then printing will make everyone immortal eventually. Well, not totally immortal, as you could still die from injuries, or if you have a brain condition that kills you in less time than it takes to replace-and-heal. But unaging and generally free of disease.
Or would you slowly lose your memory and personality over the course of the replacement?

Printing Organs

An interesting innovation of modern times is deposition printers, which can produce any 3 dimensional object by laying it down layer by layer in melted plastic, which rapidly cools and solidifies into a layer of the final object. If an layer can't support itself structurally until complete, the system can also lay down a second type of plastic that washes away when exposed to water. Although the systems tend to be expensive (none cost less than $500), once you own one, you can have all the plastic parts you want for a few cents worth of thermoplastic.
Medical doctors have especially taken note. Human cells can be grown in a lab, but only in flat sheets about one cell thick. The cells know that they shouldn't endlessly grow upon each other, because when they do that, they're typically cancer. Cells in your body grow on a framework, an extracellular matrix. And here's where they have the idea.
Since the 3d printer can print any shape, have it print an extracellular matrix for an organ, wash it, and introduce it to a glucose-and-saline medium. Inject one human cell, and a short time later, you have a fully functional organ. Since extracellular matrix parts are regularly replaced, this new organ will, after being implanted, slowly replace its plastic extracellular matrix with a real one, at which point the organ will be indistinguishable from the original. Other than the new one is fresh and healthy and will last for years longer.
This is giving me an even crazier idea, which I will go into tomorrow.

Starving AIDS

A discovery from The University of Rochester is likely to make the whole fighting AIDS thing easier: We've been doing it wrong.
Viruses usually replicate by stealing a molecule from your cell, dNTP, and interfering with this process is the first means by which most anti-viral drugs work. AIDS, however, has taken to preying on immune cells that don't have this chemical. The university discovered that AIDS instead takes a similar molecule, rNTP, and works from there.
This could lead to whole new classes of AIDS fighting drugs, ones that do actual damage to the virus's metabolism. Not yet a cure, but AIDS is now officially on the run.
Curing viral disease tends to be more difficult. We have yet to develop any real cure for the common cold, a disease that we naturally recover from in a week or two. Part of the reason for this is that virus's aren't, in most senses of the word, alive. They are naked chunks of protein progammed to replicate endlessly, like some sort of zombie. And like zombies, they tend to keep going until totally destroyed.

Magnetic Double Blind

One of the hardest hypotheses to test today is the theory that magnets can cure a surprising range of diseases and disorders, and part of it is ruling out the placebo effect. The placebo effect occurs when any treatment at all, even one that clearly has no effect (like giving the patient a sugar pill) still cures their disease because the patient expected it to happen. "I got treatment because people care about me" is a powerful thought to a person who is ailing. To rule out the placebo effect, most clinical trials do a double blind study. Neither the patients nor the doctors administering it know which is the real treatment, and which are a fake chalk tablet that only gives the impression that you're getting powerful drugs. And here's where we have the problem.
Any American who graduated the fifth grade, basically all of them, know how to tell the difference between a magnet and an inert chunk of iron. If you press it against metal and the metal sticks, it's a magnet. If you bring it up to a TV and the picture distorts, it's a magnet. If it deflects a compass needle, it's a magnet. The double blind will be ruined, I guarantee. The people with the fake magnets will find it obvious.
If we can resort to some very totalitarian methods, and we can because this study will pay handsomely and "scientific firm reserves the right to dickishly control every aspect of your life for the duration of the study" will be in the contract, if not in those exact words. If you've ever seen the X-men movie, the scene where the villain Magneto is imprisoned in a plastic bubble suspended by fiberglass line, because of his ability to control basically any piece of metal anywhere near him makes imprisoning him in a tradition prison stupid, inspires the perfect impossible-to-detect-magnetism environment ever. You will live in an all plastic and ceramic environment with no metal or electricity. You are encouraged to bring books, writing materials like pencils and paper, and metal-free hobby things. All metal or electronic devices will be confiscated for the duration of the study. You will have a device with something heavy and metal-ish sewn into a cloth pocket strapped onto you. Half of these will contain an actual magnet. The other half, an inert piece of metal of the exact same size, shape, and weight. Participants will journal their recovery from disease over the course of two weeks to a month. We will also have to keep you isolated from each other, except for maybe a ceramic-can-on-a-string telephone. We can't run the risk that you'll "test" each other's "magnets."
After the study is over, we can then reveal who actually had a magnet, and who had just a chunk of metal. And we will finally have determined if magnet therapy offers any actual benefit, or is just another attractive woo-woo claim.

Mouse Fountain of Youth

Discovery news says that a group of mice genetically engineered to age rapidly and grow telemerase when exposed to estrogen tend to recover their youth when exposed to estrogen. Already visions of a technological fountain of youth dance in many a journalist's head. Especially because telemerase is something easily obtainable that you could probably inject yourself with as early as tomorrow if you ordered it this morning.
Ah, but not so fast cowboy. The article also points out that this may be a quirk of the rapid aging genes. So maybe it might help someone with a rapid aging condition, but not provide boundless youth to whoever wants it. Even so, this is a remarkable piece of medicine going on here.

Kidney Cloning

Organ donation is an interesting thing. You can donate some things while you're still alive. A large portion of your liver, which will grow back. One of your two kidneys. One of your two lungs. (Those don't typically grow back.) Other things, you can donate when you die. Your heart. Other things, you'll probably want to wait until your death to donate, like your skin or your corneas.
I was reading earlier this week about how scientists have rebuilt lungs to improve compatibility. Essentially, your own diseased lung is rebuilt from scratch using your own stem cells, then reimplanted. They reported that this will save hundreds of lives every year, because hundreds die while waiting on donor lungs. You can also use a donor who would otherwise be incompatible, which saves even more lives.
And I was thinking, you know what other organ could benefit from this? Kidneys. Millions worldwide depend on dialysis, because their kidneys have totally failed. There's a limited number of machines, and we can't seem to build more fast enough. But if we rebuilt the patient's own kidneys, they would no longer need dialysis. It would be merely a stopgap measure to get them through the failed period, which is no longer "the rest of your short life." In fact, the more organs we could apply this to, the better the organ donation works out. Incompatibility would cease to exist, making every donated organ more useful.
But the best aspect of all was suggested by a reader of the original article who called himself "dancupid." He suggests using 3d printing techniques to lay out an artificial extracellular matrix. If that could be done, then we never need organ donation again. Each person could have an organ bank of 5 or so of their own organs, grown from a printed extracellular matrix and their own stem cells, and kept alive in life support machines. If I get stabbed in the kidneys, I can have my loved ones take a kidney from my organ bank to the hospital, where they implant it. The stabbed one can be donated to someone who couldn't afford the printed organs (and will have its cells replaced with their own), and when I get home, I print a new one in case this happens again. If my lungs should develop cancer from all the air pollution, I have a printed replacement ready to go. If my heart should give out, as happened to many of my ancestors, I have spares. In all cases, I'd cheerfully donate the old one.
....dear God, we'd be nearly immortal. We'd last as long as our brains. (You could print a new one, I suppose, but would it still be you?)

Curing ALS

Amyotrophic lateral sclerosis, known as ALS in most of the world, and "Lou Gehrig's disease" in the United States, (after a famous baseball player who died of it), is a motor neuron disease that slowly kills off the part of your brain that tells your body how to move. The result being that a person suffering from it slowly becomes more and more paralyzed until they can't breathe anymore, at which point they die. The rest of the brain is unaffected. A similar condition is Locked-in Syndrome, in which a person abruptly becomes paralyzed, usually after a stroke. (In which case the motor-control cortex of the brain probably died in the stroke.)
Motor-cortex conditions are rather baffling to treat. The muscles are technically fine, but the person can't move them. The muscles then deteriorate from a lack of moving. The problem lies in the brain, which we know the least about and are the most afraid of messing around with, lest we make it worse.
I think, in the circumstances, I would want to try to invent a cybernetic motor-cortex replacement. This would take 100 years of neurology research, and the best electronic-communication experts known to man. And having done so, no one would ever be paralyzed for brain-reasons again. If this research also found a good way to reconnect severed nerves, then all paralysis would thereafter be treatable.

News Summary

NPR says that the best way to survive in a falling elevator is not to jump at the last second, as is popularly believed, (as you could not possibly jump fast enough), but you should instead lie on the floor, and try to wedge yourself between the two walls at the last second. You'd take a beating, but you'd live. After all, it's not the fall that kills you, so much as the sudden stop at the end. Hopefully my readers will never need to know this information, but better to have and not need, then to need and not have.
Discovery News reports what female friends of mine have said to me all along: If you're female, your own body hates you with the ferocity of a thousand suns. Estogen clusters in ovulating women make it hard for them to think straight, brain scanning studies of American women showed that they want to be thinner, sometimes thinner than is biologically possible for them. Confrontation with the idea that they might be fat, even if demonstrably false, sent part of their brains into existential crisis.
There was also reported to be a crisis in groundwater, in that at the rate it is being used faster than it can be replaced (by rain, underground water flow, etc). Complete depletion would result in a massive and disastrous desertification of the area. (I do not believe their claim that this is connected to sea level rise. Groundwater has always gone towards the sea since there was a sea to begin with. Groundwater didn't come about by magic, but by rain from evaporated seawater.)
They also report that before airplanes, there were still intercontinental exchanges of disease causing viruses and bacteria, carried by duststorm. Bacteria and viruses would travel with the dust, blown by the wind, until deposited on a new land, with new hosts to infect. The disease would arrive in a weakened state, having to survive both a dry wind storm and a large amount of UV radiation, which was only partially blocked by the supply of dust.
Fark leads me to a story by ABC news, which says that a mall in St. Louis, Missouri, banned groups of unaccompanied teenagers, to the immense annoyance of said teenagers. The mall also discovered that said teenagers were not their primary patrons: the policy made all store's profits go up, even the ones catering to teenagers. The large groups hanging out tended not to spend money, preferring instead to horse around and irritate others around them.
Tomorrow I return to the mad science.

Cybernetic Replacement Parts

Sometimes we lose parts of our body from accidents, or worse, intentional mayhem. In the earliest of times, we'd make a crude prosthesis to allow the person to function, at least marginally, again. A peg leg wasn't as good as a real one, but at least one could hobble about without falling over. A hook for a hand allowed you to at least grab a sandwich, and operate a few tools. A patch, or a glass eye, allowed people to not vomit from seeing your empty eye socket. You still couldn't see, but you didn't look like a freak anymore, which helped immensely.
In modern times, prosthesis technology is way better. You can get a leg that resembles a real leg so strongly that most people won't notice the difference. (Well, when you're wearing shoes and pants. Take off the shoes and there's an obvious mechanical joint at the ankle, and if you wear shorts, the knee is also obviously mechanical.) You can get a rubber and metal hand that allows you to handle objects as well as your flesh one originally did. The hand can even "feel" heat, though is otherwise deficient in the sense of touch.
I think a team of prosthesis crafters and neurologists should team of for a next generation of prosthetics that tie into the nervous system. We could have artificial hands that have a true sense of touch, one that works as well as our flesh hands. We could have "eyes" made of camera that allow true vision. (We currently have cameras that are on the sides of dark glasses, that have an inductive tie into the nervous system, allowing a very low resolution greyscale vision. It's enough to walk around and not walk face first into a wall. Most sightless people who've received it describe it as more distracting than useful.) Neurologists would be part of the team because the prosthesis would have to receive its operating signals from the nervous system, and send data back, and using the part would be not any different than using the part you had before.
I'd suggest having the prosthesis surgically grafted to remaining bone and muscle, making it a replacement for what was lost. It should have integrated blood vessels, with "vampire" power support, a system that powers itself by extracting glucose from blood and burning that for energy, as your body does now. This technology exists now, but is rarely used.
And ultimately, I'd like to see a cyberbrain developed. A part that attaches to my nervous system and extends the ability of my brain. I know that this is possible from experiments in which mice brain cells were grafted onto electronic chips, and they integrated into each other. The resulting system was then taught to operate a flight simulator. Immediately, I would expect to achieve sharper senses. Vision uses a huge amount of our neural processing ability, but if one loses it, the brain concentrates on the other four senses, which become significantly sharper. It would also, as a mechanical part, be able to interface with non-brain objects as well. Perhaps it could connect to a computer, which I could now operate by thinking commands.
At some point in this process, I think we could develop prosthetics that are superior to our original parts. Imagine having the arms of a body builder, but not needing to exercise. Camera-based cybernetic eyes will never develop Glaucoma, cataracts, presbyopia, or macular degeneration, and would also lack the "blind spot" that our eyes have from the retina being on the wrong side of the back of our eye. Cybernetic ears could be made that respond to frequencies higher or lower than current human hearing allows, and could be made arbitrarily more or less sensitive according to the needs of the situation. (Or could even be turned off for meditation or sleeping. No more being bothered at 4am by some obnoxious guy with his stereo up way too loud.) Even obesity becomes a thing of the past. If you eat too much, you could plug yourself into the wall and power your house for a bit. (Your power bill promptly becomes replaced with your grocery bill.)
I'd also like to see cybernetic replacements for organs, which could save millions of lives worldwide. If I had an artificial heart as good (or better) as my current biological one, I'd cheerfully replace it, and my original biological one could keep alive a person who would otherwise die. (This assuming that the dying person opposes cybernetic replacements as "unnatural" or something. More likely, those dying of heart disease are the ones who wind up with artificial hearts.) Artificial kidneys would make the expensive and difficult process of dialysis a thing of the past. Artificial livers would make hepatitis a thing of the past, as its mechanical nature proves impossible to infect. Also, cirrosis as caused by alcoholism no longer need kill you. Quality of life worldwide would massively improve, and organ banks would always be able to fall back on the cybernetic versions.
The research to invent these things would be very expensive. Perhaps a corporation could be persuaded to invest for the royalties, which would assuredly be massive. Expenses would be recouped, one invention at a time.
I'd like to thank the Chinese Guy for inspiring this post.

ScanBed

Now I'm imagining a medical bed, for hospitals, that has a multitude of sensors. Thermocouples embedded in the bed notice the heat output, and hence, body temperature, of the patient. (Calculated with some complex math and physics.) Motion sensors notice the turning of the patient, and suggest moving them when this grows insufficient to prevent bedsores. Ideally, I would even like it to find a way to determine pulse rate and breathing.
All of this is logged to a small computer at the bottom, for extraction and analysis by a doctor. (Or even medical computer. The doctor should be able to retrieve a well-laid-out chart rather than seeing a table of raw numbers.) Also, alarms if certain conditions occur, like a body temperature above or below a certain point, pulse above or below a certain point. High body temperature would suggest fever, or perhaps foreign object resulting in fire danger. Low body temperature suggests hypothermia. (Or death, but I think one of the other sensors would have noticed first.) High pulse suggests distress, or imminent heart failure, whereas low pulse suggests imminent brain damage.

Combating AIDS

Acquired Immune Deficiency Syndrome, or "AIDS," is a disease that throws entire populations into panic. It's sexually transmitted, assuredly fatal, and rather miserable to have. I had to endure many public services about it in school, because it wigged people out so severely that the department of education felt compelled to step in to inform us that no, you cannot get it from toilet seats, or handshakes, or really anything that doesn't involve other people's bodily fluids going into you.
AIDS is caused by a retrovirus, HIV. (Human Immunodeficiency Virus.) I know people who deny this, but they have no evidence for that belief. Retroviruses are one of the hardest to fight, because of how they work. I had to go into a bit of biology to explain this.
Our cells are made of protein, which are controlled by our DNA. To operate DNA, it's copied into RNA, which arranges proteins into complex structures, and folds them into their final shape. Most viruses are RNA-only, because they exist to endlessly replicate themselves, and try to convert your cells into virus factories. Retroviruses, however, know how to convert their RNA back into DNA, and replace chunks of your cell's DNA with its DNA, so the next time you copy that cell, you copy that virus too. Even if you purge all the viruses out of your body, the virus can reemerge from that cell, which is the scary thing about retroviruses. However, they can also be used for good. Genetic therapies exist in which a benign retrovirus is modified to inject beneficial genes into yours, and then the virus malfunctions and "dies" afterwards. (Well, it's debatable if viruses count as "alive," as they are just chunks of RNA and protein, but it malfunctions such as to be nonfunctional.)
So, AIDS is quite prevalent in some parts of the world, and immensely terrifying even in places were infection is rare. And yet, no part of the world is totally free of infection. Is there any surprise that there's an immense demand for a cure?
We've made a lot of progress, but aren't there yet. HIV has proven quite polymorphic, responding to all attempts to fight it by rearranging itself until it is immune to what we throw at it. And yet this strength is also now its biggest weakness. One can literally mutate it to death. Unfortunately this doesn't help medically, because the virus tends to reemerge from older, more effective forms, stashed away in a random cell's DNA.
Another discovery is that a small percentage of the population is immune to bubonic plague, which ravaged Europe in the 1300s. These people are also immune to AIDS, for reasons that we don't readily understand. (This mutation assuredly developed from the plague, in which the non-immune population of Europe was devastated, leaving only those unexposed or immune to reproduce.) I see no possible connection: bubonic plague is caused by a bacteria, and AIDS by a virus. There must be some sort of third-party connection, in that some aspect of the bubonic plague immunity also makes it harder, or impossible, for HIV to gain a foothold. More research is required.
So if a person with AIDS asked me for a treatment, I think I would start with a bubonic plague innoculation, and extremely agressive genetic therapy. Along with the traditional anti-viral drugs like AZT. I would hope to reconfigure their genes until the existence of retroviruses in their body is impossible. This would also mean that any children they had would not resemble them in the slightest, but it's a small price to pay in the face of miserable death.
Also, AIDS does not kill you directly. It just destroys your immune system so that the first other disease to come along rages through your body unopposed until you die.

Bionic Animals

People care a lot for animals. What sucks the most for them is when they loose limbs. It further hinders their ability to survive.
However, bionics as a field has stepped up to the plate. I've heard of everything from a turtle being given new fins, to dolphin getting a new tail, to an eagle getting a new beak, to a cockatoo having its entire legs replaced.
Perhaps people feel that it's silly to expend so much effort on an animal, but it's good practice for us humans, who also lose body parts at a larger rate than we'd like.

Life Analysis Device

Once upon a time there was an artist/engineer who made a system he called the Narsci-system, after Narcissus, the greek legend of a man in love with himself, and system, as it was made of multiple sensors that communicated with a single point for concatenation and analysis. Also, because it was "Narcissistic" to pay so much attention to the goings on of his own body.
So I'm imagining a medical version of this. It would continuously scan and record the goings on of the user's body, and communicate back to a sophisticated computer for analysis. The computer, using the best advice medical doctors could give, would give advice about certain situations. If one hadn't gone to bed for 20 hours straight, it would suggest doing so. It would suggest morning jogs, and even tell you to speed up or slow down. (There is an ideal heart rate to achieve in aerobic exercise.) It would complain if you moved too little, as measured by the accelerometer, as this suggests laziness, or a lack of exercise, or too much, as this suggests the need for a day off. If it found a problem it didn't know about, it would suggest a medical checkup.
And in extreme situations, maybe it could even actively intervene. Heart rate dangerously low? Stimulant injection! EEG showing abnormality? Cortical stimulation! Dangerous level of vibration? Deploy airbag!

Cloning Blood

Ever since doctors have had the ability to transfuse blood, we've needed a basically unlimited supply of the stuff. There's nothing worse for a person than running out of blood, since it kind of starves your organs of the nutrients and oxygen that they need to survive, and there's a distinct risk of this in severe injuries and intensive surgery. Even a single donor can save several lives. Discovering blood-types and how they deal with combinations was a major breakthough here. In the absense of properly available blood, a saline solution can still keep the circulatory system's volume up, making the remaining available blood more useful to the body.
But the need for blood is tempered by the risk of blood-bourne disease. Severe diseases like Hepatitus and AIDS can be transmitted through blood transfusions. The ideal donor would be an O- virgin, 12 years old or younger, who subsisted on a pure vegan diet of sunshine, water, and unicorn farts, and was proven to be free of all known diseases. Since the pool would be extremely limited if doctors actually held out for this, compromises have been made to remove the most likely carriers of disease, and to categorize blood to make the most use of the available supply. Blood donors can give up to a pint at a time, which the donor will slowly re-grow over a period of about 56 days. Blood donors typically get a snack of punch and cookies to replenish lost fluid and blood sugars, minimizing any negative effect that losing blood could have on them. Though many milions of people worldiwde heroically donate, people still die from lack of access to blood, because the need is far bigger than the supply.
Discovery news reports today that a biotech firm is now cloning blood from umbilical cords, producing massive amounts of disease-free blood from even one. Even better, the process is extremely fast. The blood is produced in far less time than the natural version, so in case of a massive emergency, a large supply of blood could be quickly made available.
A better process still would be completely artificial blood, as that could be made without limit. Blood is made of things that aren't very expensive: Carbon, Oxygen, Hydrogen, and a small amount of Iron. Though the chemistry is complex, once a process could be set up, machines could crank out gallon after gallon after gallon of the stuff and rush it to hospitals worldwide. The volume would be so great that pipe-based transport would be a worthwhile investment. Unlimited transfusable blood would have all sorts of insane implications. For one, poisoning could be cured by blood flushing, in which your blood would be replaced until no trace of the poison remained. For another, hemodialysis would become a very different, and probably much cheaper, process. Bacterial or viral diseases could also probably be flushed away. The waste blood could be used to grow flowers or something.