Saturday, May 26, 2007

"Virtual Man-4D"

Virtual human puts doctors inside their patients
Last updated at 10:02am on 24th May 2007
Researchers say they have developed the most detailed model of a human yet, a movable "4D" image that doctors can use to plan complex surgery or show patients what ailments look like inside their bodies.
Called Caveman, the larger-than-life computer image encompasses more than 3,000 distinct body parts, all viewed in a booth that gives the image height, width and depth. It also plots the passage of time - the fourth 'dimension.'
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Mr Sensen with the groundbreaking '4D' model
Scientists can layer on the unique visuals of patients, such as magnetic resonance images, CAT scans and X-Rays, giving physicians high-resolution views of the inner workings of the body while it appears to float within arm's reach.
It will help researchers study the genetics of diseases such as cancer, diabetes, muscular sclerosis and Alzheimer's, said officials at the University of Calgary, which has worked on the system for six years.
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Doctors will be able to show patients what is going on inside their bodies Mr Sensen said
"Today, this kind of a model is unique in the world. It's the only one that is complete," said Director Christoph Sensen.
The model was started partly due to a desire among massage therapy teachers for a more intricate picture of muscles and bones.
Seen through 3D glasses in a booth, the model appears to stand in front of the viewer. As in a video game, the controller can manipulate it and focus on body parts - skin, bones, muscles, organs and veins.
"We say that killing monsters is fun, but curing cancer is more important," Andrei Turinsky, a mathematician and computer scientist, said as he moved the model around using a joystick.
The closer the image gets, the further into the body the viewer appears to travel. It is difficult to resist trying to touch it. The image can also be loaded on to regular computers, to be viewed off site.
The medical community will benefit by being able to merge patients' diagnostic results - such as computerized internal images and blood tests - in one place, allowing specialists to work together more closely, Mr Sensen said.
In addition, surgeons can use to plan surgeries before conducting them and use it as a teaching tool.
Patients will also gain much more understanding about their own conditions, he said.
"We want to do this so any patient can walk up to a machine with a surgeon in tow who says, 'This is what it looked like six weeks ago and this is what it looked like today. You better get surgery now'."
The next step is to develop versions to sell to hospitals around the world, and adding a touch element to the image.

Saturday, April 21, 2007

Radio Resistant Bacteria

Electron micrograph of a cross-section of a D. radiodurans tetracoccus (cluster of four cells).

Fifty years ago, scientists experimenting with gamma radiation to sterilize canned foods were surprised to find spoiled meat in cans zapped with what they thought were lethal levels of ionizing radiation (IR). Inside the bulging cans, they discovered a strain of bacteria now called Deinococcus radiodurans. This extremely resilient microbe can endure 100 times the IR levels that kill other bacteria and levels 2,000 times higher than the lethal human dose.

A 2004 study by Michael Daly et al. found that IR-resistant and IR-sensitive cells had significantly different mineral concentrations, lending support to a role of manganese and iron in recovery. The researchers showed that the most resistant cells contained about 300 times more manganese and three times less iron than the most sensitive cells. In a new study investigating the functional consequences of this disparity, Daly et al. show that high cytosolic manganese and low iron concentrations facilitate resistance by protecting proteins, but not DNA, from IR-induced oxidative damage. Their findings offer a novel perspective on the long-cryptic nature of D. radiodurans resistance, shifting the focus of toxicity and resistance away from DNA damage and repair toward a potent form of protein protection.

To understand the nature of manganese protection in cells, the researchers then irradiated IR-sensitive and IR-resistant bacteria and compared their levels of oxidative protein damage. The sensitive cells with the lowest manganese to iron concentration ratios, they found, sustained high levels of protein oxidation; the resistant cells with the highest ratios had no detectable protein oxidation. They showed that proteins purified from D. radiodurans are not inherently oxidation-resistant, and when cells were depleted of manganese, cells were rendered sensitive to IR and protein oxidation. This suggests that the microbe actively offsets the effects of IR by protecting proteins using manganese, specifically with divalent manganese (Mn(II)) ions.

Electron micrograph of a cross-section of a D. radiodurans tetracoccus (cluster of four cells).
Resistant bacteria, the researchers suspected, might use Mn(II) to transform superoxide radicals, which can’t easily cross the cell membrane, into hydrogen peroxide, which can. And that’s what they found: irradiated D. radiodurans and a second resistant bacteria with high manganese concentrations (Lactobacillus plantarum) released hydrogen peroxide (likely as a product of the “redox” reactions that neutralize superoxide radicals), while sensitive and non-irradiated resistant bacteria did not. The researchers went on to show that the resistance of normal D. radiodurans can be controlled externally by inhibiting manganese redox recycling.
In the context of previous studies, these results suggest that D. radiodurans relies not on a highly specialized DNA repair machinery, but on a detoxifying mechanism associated with the microbe’s unusual intracellular environment. Most organisms contain near-millimolar concentrations of iron, which under IR will contribute to the formation of hydroxyl radicals and superoxide radicals. In resistant bacteria, millimolar Mn(II) concentrations appear to protect proteins from oxidative damage by eliminating superoxide and its derivatives. This oxidative protection may in turn shield proteins involved in DNA repair, and subsequently allow them to quickly heal DNA lesions, which in sensitive bacteria turn lethal because their repair proteins are ravaged by radiation.

The Implications:

This new model of radiation toxicity opens up novel avenues for radioprotection in diverse settings. Individuals exposed to chronic or acute doses of radiation could potentially benefit from treatments that deliver purified D. radiodurans Mn complexes into their cells. Similarly, the toxic effects of radiation therapy in cancer patients might be ameliorated by antioxidant drugs based on such a protection paradigm. And given that many bacteria, such as S. oneidensis, with favorable bioremediation functions are extremely sensitive to radiation, the new insight on how D. radiodurans survives radiation might prove useful in efforts to contain the toxic runoff from the immense radioactive- and heavy-metal-contaminated waste sites left over from the Cold War.

These findings are reprinted from PLOS Biology Research Article Written by Liza Gross.

My Take:

I find it extremely significant to know that there are such viable bacteria on earth and this should not be at all new to us since we are already aware of the possibility of some forms of bacteria that can remain dormant and thus be totally capable of enduring space travel and the various and rigorous fluctuations in temperature and environments. Some forms of bacteria can survive in acids so is it even conceivable that life on this planet may have travelled vast distances in space to land on good old mother earth in the form of bacteria and viruses and/or are our bacteria and viruses for that matter leaving mother earth and heading for some distant home in our galaxy carrying their mutations from one planet to another. What we do here on earth, as we always seem to realize down the road, has far reaching implications to others and perhaps to others yet to exist.

Thursday, April 19, 2007

The Medical Arm Of Medicine

The Medical Arm of Medicine

Mechanical hands can now be used for neurosurgery of the brain. New technology researched and manufactured in Calgary, Alberta, allows Doctors to guide complex neurosurgery using MRI real time imagery.
Tumours can be removed from brain tissue for example, with surgical precision helping minimize human error from hand tremors. The robotic hands are operated remotely and mimic the movements of a surgeons hands with incredible precision. Sensors, lights, and microphones recreate the sights, sounds and touch of surgery. The cost of the robot that may see service as soon as the summer of 2007, is a mere 27 million dollars.
I believe the seed for this kind of technology decends from the Canada Arm technology used on the Space Shuttle as well as what was planted years ago with the advent of the internet and teleradiology. At a Nuclear Medicine trade show in Chicago in the late 80's there was a booth getting lots of attention. It was quite impressive looking lots of military and CIA personnel around displaying images of X-rays just taken at a base in Germany. The significance of this was being able to diagnose diagnostic tests remotely thousands of miles away utilizing powerful computers and digital technology at the time thus teleradiology was born. The military applications were seen as enhancing the ability to get injured soldiers back in the line of duty as soon as possible as well as enhancing timely decisions with regards to medical treatment in saving soldiers lives.
The war machine will be happy to know now that not only will they be able to see the wounded soldiers medical problems via computerized imagery transmission, but also will be able to operate on the soldier with robotic hands being controlled from a remote station somewhere in good ole' USA while the soldier lay wounded say, in the Middle East or anywhere in the world for that matter.
I guess the military medics will not only be concerned about the biological aspects of infection from bacteria and viruses that can reap havoc on the injured in the field but also concerned with the electronic viruses that will be able to reap havoc on computerized technology increasing the fronts on which battles can be fought thus adding another dimension to the medical arena of disease treatment.
One wouldn't want the robotic hands to fail (computer crash), in the middle of removing shrapnel from the heart muscle of a wounded soldier on the battle field.
A little bit of 10w30 for the lubrication of the Robotic Hands, a software antivirus for the computer hard drive and anti-viral/anti-bacterial medication for the wounded soldier and voila ......medicine for humans and medicine for machines. I guess we were headed that way anyhow. Don't forget to shut off the power button.

Tuesday, March 20, 2007

"Medicine and Laughter"

A woman told the vet that something was wrong with her dog. He examined the animal and told her the dog was dead."I don't believe you", she said, "I'd like a second opinion"The vet said that would be fine. He went into the other room and got a cat. He put the cat up on the table with the dog. The cat sniffed the dog and jumped down. The vet then got a golden lab, put him on the table and the lab sniffed and jumped down.The vet tells the lady again, "I'm sorry, but your dog is definitely dead. That will be $600 for the exam.""$600 is ridiculous, what are the charges for?" she exclaimed."$600 is a bargain," the vet explained. "$50 for me and only $550 for the cat scan and lab work."

Saturday, March 17, 2007

How Medical Is Death?

How Medical Is Death?
I guess the “medical-ness” of death depends on your attachment to the deceased and perhaps if you have any familiarity with medicine at all in any form. So perhaps my view of a recent funeral experience allowed me to view death as both medical and emotional, and the funeral if not fun, enlightening, maybe because I am both a medical professional and had minimal attachment to the deceased.

Now having assisted on three autopsies in my lifetime and all three in 1989-1990, I have gained an appreciation of viewing humans from the inside out rather than of course our two dimensional mirror view of ourselves from the outside in. The first two autopsies were both from the same accident. Actually six tree planters were killed in a van rollover on the way to their planting site. The pathologist I was helping at the time was filling in for our regular guy and was an older gentleman sixty or seventy years young and just was not moving with the finesse, grace or speed that I am sure he exhibited in earlier years. This equates to the body being exposed to air for longer than what would normally occur. It took some four hours. It got smelly.

The mask did not or could not hide the stench that emanated from the decaying body. There was no suction or refrigeration in our post mortem room so time was of the essence. After I was taught the typical “Y” incision on the chest I was instructed on how to cut the ribs to remove the rib cage and the sternum, as well as the technique of using a “Dixie cup” to scoop out blood that had pooled in the abdomen from a major abdominal bleed that had leaked into the cavity of the deceased, had pooled there and had to be measured. I felt like I was in some macabre movie, very uncomfortable I remember but determined to learn my part in this procedure.
What struck me the most during my gruesome tasks was how compact we are inside and how nicely and snugly everything fits together. The frog dissection in biology 101 did not prepare me for this. Having studied anatomy in 2 dimensions from text books definitely is not the same emotional feel you have from hands on, so to speak.
As we continued to saw a skull, remove a brain, a heart, and other organs my detachment to the human experience became all too clear. We are merely tissue and will no doubt one day be dust again. There was no personality to excise, to save in a bottle or to examine on a slide. There were no memories to collect from the deceased and label with his belongings. There was no internal meter declaring how many times that heart had beat or skipped a beat for that matter. All declaration of self and psyche were vacant, from a medical point of view anyway.

My first exposure to death came in the form of a pigeon named after my oldest sister Gail. Now one day Gail took it upon herself to land on the back of our Dalmatian, figuring all is well, since she had ridden on the back of our Collie cross old Smokey numerous times. I heard a bit of commotion outside this day and opened the door to see Sparky, the Dalmatian, sitting erect and innocent with one small feather protruding from her mouth and no Gail was ever seen again. I made my own conclusions.

A pigeon death, however it met it, is no comparison to that which extols emotional wrath in the human arena of death and coping. I thought during this funeral, of all I could remember who had died that I had been close to; My uncle when I was 14 years old, my brother, my best friend, my nephew, my daughter, and my mother. All who exacted different emotions in different ways? I actually saw my brother take his last breath and wondered years later if I should have saved it, for what purpose I cannot be sure but it might have been nice to have that last bit of life, when everything else was gone.

My medical experience with death happened when I first started working in Nuclear Medicine. I was at the Isaac Walton Killam Hospital for Children in Halifax in the mid 1980’s. Lots of cancer patients came and went thru the doors of our department. On one such occasion I had injected a 7 month old with a tumour imaging agent called 67 Gallium Citrate on a Tuesday and would image two days later on Thursday. I called for my patient on Thursday anticipating what may or may not show on the scan. After all I was 6 months new to this job, just graduated and wanted to be keen. There was a knock on the door and in walked a nurse carrying a red tool box, you know the kind I mean, the ones from Canadian Tire, red tin with the black handles. I asked how I could help her and she opened the tool box to reveal my patient. The tube from the respirator was still inserted in her little mouth and I was shocked and horrified. I was angered at the coldness of how she was delivered to me and dumbfounded by the emerging events. I was going to have to pick up this little dead body and scan it. They wanted the procedure done to see where her tumour was. I understood about that. It may help in understanding disease in others. I also understood the means of delivery to us, a most inconspicuous way to move a dead little body about the hallways of an extremely busy facility with wondering eyes everywhere, its human nature. This would be my first experience in touching someone dead. I was struck by the coldness of the skin but the experience would not be my last.

At a recent wake and funeral, I became detached from my surroundings and began to drift in thought to past experiences with death and of all things autopsies. Most of what I reminisced has been written above. I used to observe funerals as an altar boy. I remembered we got $5.00 for serving at one. I never quite understood however, why people spent time coming together during death but so often did not spend time with the deceased in life. Respect and courtesy to the survivors and deceased I guess. Since I am here at the wake and the deceased has brought us all here with her untimely death, as most seem to be, no matter what the age, I decided to learn more about her through those around who had come to share in her passing. It was sad of course but not overwrought with bursts of emotions as some times is the case during tragic losses, but a much more understanding and accepting departure with intersperses of laughter which at times allowed me to think on autopsies, deaths of bygone years, finger foods and where all guests would be gathering for a post luncheon after the funeral tomorrow. Haemostat.

Tuesday, March 13, 2007

I love this quote by Mary Wollstonecraft,the mother of Mary Shelley, author of Frankenstein:

"It appears to me impossible that I should cease to exist, or that this active, restless spirit, equally alive to joy and sorrow, should only be organized dust-- ready to fly abroad the moment the spring snaps, or the spark goes out, which kept it together. Surely something resides in this heart that is not perishable--and life is more than a dream."

Nuclear Medicine Imaging......what is it?

This is a Gamma Camera. It is Gamma rays as opposed to X-rays that we detect. The only difference between the two is where they originate. X-rays come form orbiting electrons of an atom that are knocked out of orbit or moving to a different orbital level. Gamma rays come from the nucleus of and atom during radioactive decay. Radioactive decay is simply a physical process whereby an atom has too many protons or neutrons and is very unstable and in an attempt to become stable emits radiation. Nuclear medicine likes the Gamma rays which we use for imaging and the Beta particles which we use for therapies. The radiation that we use is 99mTechnetium usually attached to a drug to deliever it to the organ we want to scan. Once the drug radiation-combination is incorporated into the organ of interest, we image. Sometimes we image as the radiation is being delievered and sometimes there are delays of up to two or three days for some studies. Our studies are functional which allows us to get an indication of organ function over a period of time. This is where I will hemostat. If you want more info you can always google. If you would like to ask me a question concerning nuclear medicine drop me an email. I am sure that this discipline will come up again in topics once we get going.