Medical breakthroughs 2003
July 29, 2003 | 12:00am
It’s now mid-2003 a good time to consult with medical experts in various disciplines to get a line on the hot topics in the world of health this year. From the many health advances that my specialist friends discussed with me and the various references they provided, I narrowed the list to four breakthroughs which I think will make the biggest impact on your life and that of your family today and in the future. So here are the current breakthroughs that can help you live longer and better.
A new three-dimensional scan lets doctors see the inner workings of your body in precise detail, enabling earlier and more accurate diagnosis. The new imaging system combines two tests you have probably heard of — computerized tomography (CT) and the scans of positron-emission tomography (PET).
CT scans detect tiny anatomical abnormalities by generating cross-section pictures of the body, like pieces of bread sliced from a loaf. PET measures concentrations of subatomic particles called positrons in living tissue to create images that highlight areas of increased metabolic activity. Individually, each procedure only catches some early tumors, so patients often must have both scans separately.
The combined technologies use a single new machine to produce state-of-the-art PET and CT scans simultaneously, then fuse them into a single 3-D image using a built-in computer. "Combining PET and CT represents an entirely new dimension in imaging," says PET pioneer James Mountz, MD, PhD, professor of radiology at the University of Alabama. "It can detect cancer, heart disease, and brain disorders earlier and better than ever."
PET-CT scans especially hold potential for detecting cancers of the breast, lung, colon, and lymph nodes. "With the PET alone, you can see the abnormality, but you can’t tell where it is located," Mountz explains. "With PET-CT, you can see the lesion and determine its position with great accuracy. It can also provide more accurate staging and aid in the planning of radiation or surgery. Since PET-CT scans can help doctors determine whether a particular tumor is malignant or benign, they could greatly reduce the number of unnecessary biopsies. That’s a major advance."
A protein that acts like Miracle-Gro for bone promises to speed healing for back-surgery patients and almost guarantees success. Bone morphogenic protein (BMP) is a natural compound that stimulates bone growth. Twenty-four types of BMP have been identified; one of them can now be produced in bulk using genetic engineering.
The US FDA approved recombinant BMP#2 (rBMP-2) in July last year for connecting vertebrae when a disk is removed during spinal fusion surgery. Usually, doctors must use bone graft harvested from the patient’s pelvis, which requires painful surgery and prolonged recovery time. The protein offers a quick alternative. "It’s pretty amazing stuff," says Daveed Frazier, MD, professor of orthopedic surgery at Columbia University in New York. "New bone grows completely within three months, which is a lot faster than even the best bone graft, and there’s virtually no non-union risk." Depending on the patient’s health, bone regeneration with the new process takes about half as long as before.
Soon, doctors could also be using rBMP-2 to speed the healing of bone fractures. "Now, when an elderly woman breaks a hip, it’s very serious," says Randall Hendricks, MD, an orthopedic surgeon at Central States Orthopedic Specialists in Tulsa, Oklahoma. "But with BMP, she might be back on her feet in as little as three weeks." It also has potential as a treatment for osteoporosis. "In the not-too-distant future, we might inject it into women’s bones and see strong new bone develop," Frazier says.
Orthopedic surgeons are just beginning to perform spinal fusions using rBMP-2. In follow-up studies over five years, the new bone has stayed strong without causing any significant problems. "I’ll feel a lot better when we have a 20-year data," Frazier says, "but so far, so good."
Blood substitutes are making tentative strides toward acceptance in the emergency and operating rooms — especially in conditions where the patient may be bleeding profusely and near death and there is no time for blood typing or running to the refrigerator for whole blood, if available. PolyHeme and another sub, Hemopure, are currently awaiting US FDA approval; a third, Hemolink, is undergoing clinical trials.
They all contain hemoglobin (the molecule that carries oxygen) extracted from whole blood and chemically modified to maintain its effectiveness. "It’s elegant," says Ernest E. Moore, MD, a trauma surgeon at the Denver Heart Medical Center. "The proteins for blood type are on the cell membrane. By using just hemoglobin, there is no cell membrane," meaning the patient’s type doesn’t matter.
Because the substitutes last only about 24 hours inside the body, they’re strictly stopgap. "But with patients stabilized on a blood substitute, you have a day to either bring whole blood to them or transport them to it," Moore says. In rare cases, side effects such as high blood pressure, kidney failure, and allergic reactions can occur.
As red as the real thing but a little thinner, the substitutes appear to be just what the emergency doctor ordered for everything, from industrial explosions to terrorist attacks. But they will probably be most widely used during everyday surgery, Moore explains, saving precious whole blood for the conclusions of procedures. While the products await government approval, the US FDA has allowed their "compassionate use" in special cases – for example, with Jehovah’s Witnesses, whose religion prohibits whole-blood transfusions.
Despite their potential, blood substitutes won’t make the real thing obsolete. "Eventually, people would still need whole blood," says Peter Page, MD, senior medical officer of the American Red Cross.
Figuring out what kind of drug you need – and exactly how much – has been largely a matter of trial and error. But a new test is helping physicians zero in on the best medications and dosing based on your genetic makeup.
Haplotyping, or HAP technology, was developed by scientists at Genaissance Pharmaceuticals, a New Haven, Connecticut, biotechnology company. It allows doctors to screen patients’ blood or saliva for subtle genetic variations that affect reactions to common asthma medications and chemotherapy drugs used primarily to treat children with leukemia. Already, the technology is helping protect patients from dangerous, even fatal, drug overdoses.
"In the not-too-distant future," according to Richard Judson, PhD, senior vice president for medical affairs at Genaissance, "we envision physicians taking a swab of saliva, running it through a machine, and quickly learning which drug and dosage will work best for that person in treating a broad range of conditions."
While the machine may be a long way off, the process is already making a progress. At the University of Cincinnati, Stephen Liggett, M.D., a professor of medicine and molecular genetics, has used HAP technology to predict asthma patients’ reactions to albuterol, a drug that is commonly prescribed to treat this complex disease. Before haplotyping, people who did not experience relief from a standard dose of albuterol were often prescribed a higher one, but that can cause heart-rate spikes, tremors and even asthma attacks. "Now, we can predict who will and who won’t respond to albuterol," Liggett says. "Those who won’t can be given other medications immediately."
HAP technology is still experimental and is currently available only in clinical trials. But evidence is mounting that it has a wide range of possible applications. In April 2002, Genaissance scientists demonstrated the tests’ ability to predict which of three familiar cholesterol-lowering medications — Zocor, Lipitor, or Pravachol — works best in different individuals based on variations in 27 genes. Personalizing prescriptions according to a patient’s genetic profile, Liggett says, is "the future of drug therapy!"
A new three-dimensional scan lets doctors see the inner workings of your body in precise detail, enabling earlier and more accurate diagnosis. The new imaging system combines two tests you have probably heard of — computerized tomography (CT) and the scans of positron-emission tomography (PET).
CT scans detect tiny anatomical abnormalities by generating cross-section pictures of the body, like pieces of bread sliced from a loaf. PET measures concentrations of subatomic particles called positrons in living tissue to create images that highlight areas of increased metabolic activity. Individually, each procedure only catches some early tumors, so patients often must have both scans separately.
The combined technologies use a single new machine to produce state-of-the-art PET and CT scans simultaneously, then fuse them into a single 3-D image using a built-in computer. "Combining PET and CT represents an entirely new dimension in imaging," says PET pioneer James Mountz, MD, PhD, professor of radiology at the University of Alabama. "It can detect cancer, heart disease, and brain disorders earlier and better than ever."
PET-CT scans especially hold potential for detecting cancers of the breast, lung, colon, and lymph nodes. "With the PET alone, you can see the abnormality, but you can’t tell where it is located," Mountz explains. "With PET-CT, you can see the lesion and determine its position with great accuracy. It can also provide more accurate staging and aid in the planning of radiation or surgery. Since PET-CT scans can help doctors determine whether a particular tumor is malignant or benign, they could greatly reduce the number of unnecessary biopsies. That’s a major advance."
The US FDA approved recombinant BMP#2 (rBMP-2) in July last year for connecting vertebrae when a disk is removed during spinal fusion surgery. Usually, doctors must use bone graft harvested from the patient’s pelvis, which requires painful surgery and prolonged recovery time. The protein offers a quick alternative. "It’s pretty amazing stuff," says Daveed Frazier, MD, professor of orthopedic surgery at Columbia University in New York. "New bone grows completely within three months, which is a lot faster than even the best bone graft, and there’s virtually no non-union risk." Depending on the patient’s health, bone regeneration with the new process takes about half as long as before.
Soon, doctors could also be using rBMP-2 to speed the healing of bone fractures. "Now, when an elderly woman breaks a hip, it’s very serious," says Randall Hendricks, MD, an orthopedic surgeon at Central States Orthopedic Specialists in Tulsa, Oklahoma. "But with BMP, she might be back on her feet in as little as three weeks." It also has potential as a treatment for osteoporosis. "In the not-too-distant future, we might inject it into women’s bones and see strong new bone develop," Frazier says.
Orthopedic surgeons are just beginning to perform spinal fusions using rBMP-2. In follow-up studies over five years, the new bone has stayed strong without causing any significant problems. "I’ll feel a lot better when we have a 20-year data," Frazier says, "but so far, so good."
They all contain hemoglobin (the molecule that carries oxygen) extracted from whole blood and chemically modified to maintain its effectiveness. "It’s elegant," says Ernest E. Moore, MD, a trauma surgeon at the Denver Heart Medical Center. "The proteins for blood type are on the cell membrane. By using just hemoglobin, there is no cell membrane," meaning the patient’s type doesn’t matter.
Because the substitutes last only about 24 hours inside the body, they’re strictly stopgap. "But with patients stabilized on a blood substitute, you have a day to either bring whole blood to them or transport them to it," Moore says. In rare cases, side effects such as high blood pressure, kidney failure, and allergic reactions can occur.
As red as the real thing but a little thinner, the substitutes appear to be just what the emergency doctor ordered for everything, from industrial explosions to terrorist attacks. But they will probably be most widely used during everyday surgery, Moore explains, saving precious whole blood for the conclusions of procedures. While the products await government approval, the US FDA has allowed their "compassionate use" in special cases – for example, with Jehovah’s Witnesses, whose religion prohibits whole-blood transfusions.
Despite their potential, blood substitutes won’t make the real thing obsolete. "Eventually, people would still need whole blood," says Peter Page, MD, senior medical officer of the American Red Cross.
Haplotyping, or HAP technology, was developed by scientists at Genaissance Pharmaceuticals, a New Haven, Connecticut, biotechnology company. It allows doctors to screen patients’ blood or saliva for subtle genetic variations that affect reactions to common asthma medications and chemotherapy drugs used primarily to treat children with leukemia. Already, the technology is helping protect patients from dangerous, even fatal, drug overdoses.
"In the not-too-distant future," according to Richard Judson, PhD, senior vice president for medical affairs at Genaissance, "we envision physicians taking a swab of saliva, running it through a machine, and quickly learning which drug and dosage will work best for that person in treating a broad range of conditions."
While the machine may be a long way off, the process is already making a progress. At the University of Cincinnati, Stephen Liggett, M.D., a professor of medicine and molecular genetics, has used HAP technology to predict asthma patients’ reactions to albuterol, a drug that is commonly prescribed to treat this complex disease. Before haplotyping, people who did not experience relief from a standard dose of albuterol were often prescribed a higher one, but that can cause heart-rate spikes, tremors and even asthma attacks. "Now, we can predict who will and who won’t respond to albuterol," Liggett says. "Those who won’t can be given other medications immediately."
HAP technology is still experimental and is currently available only in clinical trials. But evidence is mounting that it has a wide range of possible applications. In April 2002, Genaissance scientists demonstrated the tests’ ability to predict which of three familiar cholesterol-lowering medications — Zocor, Lipitor, or Pravachol — works best in different individuals based on variations in 27 genes. Personalizing prescriptions according to a patient’s genetic profile, Liggett says, is "the future of drug therapy!"
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