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Thursday, March 31, 2011

High Blood Pressure Causes

Understanding High Blood Pressure -- the Basics

High blood pressure, also known as hypertension, is the most common cardiovascular disease.
If you have high blood pressure, you'll probably find out about it during a routine checkup. Or, you may have noticed a problem while taking your own blood pressure. But be sure to see your doctor for a definite diagnosis, and take the opportunity to learn what you can do to bring your blood pressure under control.
Blood pressure refers to the force of blood pushing against artery walls as it courses through the body. Like air in a tire or water in a hose, blood fills arteries to a certain capacity. Just as too much air pressure can damage a tire or too much water pushing through a garden hose can damage the hose, high blood pressure can threaten healthy arteries and lead to life-threatening conditions such as heart disease and stroke.
From symptoms to treatment to prevention
Hypertension is the leading cause of stroke and a major cause of heart attack. In the U.S. alone, over 74 million people have high blood pressure.
How Is Blood Pressure Measured?
A blood pressure reading appears as two numbers. The first and higher of the two is a measure of systolic pressure, or the pressure in the arteries when the heart beats and fills them with blood. The second number measures diastolic pressure, or the pressure in the arteries when the heart rests between beats.
Normal blood pressure rises steadily from about 90/60 at birth to about 120/80 in a healthy adult. If someone were to take your blood pressure immediately after you'd delivered a speech or jogged five miles, the reading would undoubtedly seem high. This is not necessarily cause for alarm: It's natural for blood pressure to rise and fall with changes in activity or emotional state.
It's also normal for blood pressure to vary from person to person, even from one area of your body to another. But when blood pressure remains consistently high, talk with your doctor about treatment. Consistently high blood pressure forces the heart to work far beyond its capacity. Along with injuring blood vessels, hypertension can damage the brain, eyes, and kidneys.
People with blood pressure readings of 140/90 or higher, taken on at least two occasions, are said to have high blood pressure. If the pressure remains high, your doctor will probably begin treatment. People with blood pressure readings of 200/120 or higher need treatment immediately. People with diabetes are treated if their blood pressure rises above 130/80, since they already have a high risk of heart disease.
Researchers identified people with blood pressures slightly higher than 120/80 as a category at high risk for developing hypertension. This condition is called prehypertension and affects an estimated 50 million American men and women. Prehypertension is now known to increase the likelihood of damage to arteries and the heart, brain, and kidneys, so many doctors are now recommending early treatment, though there is no evidence that this helps in the long run.
Even so, many people with high blood pressure don't realize they have the condition. Indeed, hypertension is often called "the silent killer" because it rarely causes symptoms, even as it inflicts serious damage to the body. Left untreated, high blood pressure can lead to vision problems, as well as to heart attack, stroke, and other potentially fatal conditions, including kidney failure.
Hypertension may also lead to heart failure, a common but disabling condition that can cause breathing problems. Patients who have very high blood pressure are said to have malignant hypertension, with a diastolic pressure usually exceeding 130 or a systolic pressure above 200. Malignant hypertension is a dangerous condition that may develop rapidly and cause organ damage quickly -- it requires immediate medical attention.
Fortunately, high blood pressure can be controlled effectively. The first step is to have your blood pressure checked regularly.
Who Gets Hypertension?
High blood pressure is more likely in people who:
  • Have a family history of high blood pressure, heart disease, or diabetes
  • Are black
  • Are greater than age 55
  • Are overweight
  • Are not physically active
  • Drink excessively
  • Smoke
  • Eat foods high in saturated fats or salt
  • Use certain medications such as NSAIDs, decongestants, and illicit drugs such as cocaine

What Causes High Blood Pressure?

Essential Hypertension
In as many as 95% of reported high blood pressure cases in the U.S., the underlying cause cannot be determined. This type of high blood pressure is called essential hypertension.
Though essential hypertension remains somewhat mysterious, it has been linked to certain risk factors. High blood pressure tends to run in families and is more likely to affect men than women. Age and race also play a role. In the U.S., blacks are twice as likely as whites to have high blood pressure, although the gap begins to narrow around age 44. After age 65, black women have the highest incidence of high blood pressure.
Essential hypertension is also greatly influenced by diet and lifestyle. The link between salt and high blood pressure is especially compelling. People living on the northern islands of Japan eat more salt per capita than anyone else in the world and have the highest incidence of essential hypertension. By contrast, people who add no salt to their food show virtually no traces of essential hypertension.
Many people with high blood pressure are "salt sensitive," meaning that anything more than the minimal bodily need for salt is too much for them and increases their blood pressure. Other factors that have been associated with essential hypertension include obesity; diabetes; stress; insufficient intake of potassium, calcium, and magnesium; lack of physical activity; and chronic alcohol consumption.
Secondary Hypertension
When a direct cause for high blood pressure can be identified, the condition is described as secondary hypertension. Among the known causes of secondary hypertension, kidney disease ranks highest. Hypertension can also be triggered by tumors or other abnormalities that cause the adrenal glands (small glands that sit atop the kidneys) to secrete excess amounts of the hormones that elevate blood pressure. Birth control pills -- specifically those containing estrogen -- and pregnancy can boost blood pressure, as can medications that constrict blood vessels.

Wednesday, March 30, 2011

new imaging technique to advance robotic surgery for patients

NYU Langone offers new imaging technique to advance robotic surgery for patients

First center in the world to use fluorescence imaging technology

NYU Langone Medical Center completed its first surgery this month using a new near-infrared fluorescence imaging guided system available on the da Vinci Si Surgical System ,the most advanced robotic surgical system in the world. The result is a greatly enhanced visual field, allowing finer assessment and more precise operations. NYU Langone is the first in the world to utilize the enhanced imaging guidance system for selective arterial clamping during kidney sparing surgery for patients with kidney cancer and is among small select group of hospitals in the country and the only one in the northeast to have this technology.

The specially designed camera and endoscopes allow surgeons at NYU Langone's Robotic Surgery Center to capture images of tissue and surrounding blood vessels by injecting a unique fluorescence dye that is activated by near-infrared light.

"Florescence imaging combined with the new 3-D HD camera scopes gives us clear anatomical landmarks to better map the patient's vascular anatomy – it's changing the way we perform surgery," said Michael Stifelman, MD, associate professor, Department of Urology and director, Robotic Surgery Center at NYU Langone Medical Center. "We can now perform complex kidney surgery in a more sparing manner using a minimally invasive approach. The imagery is so precise we can temporarily stop blood flow to only the part of the kidney needing dissection, allowing the rest of the kidney to remain perfused which prevents potential damage to the healthy tissue."

The new technique incorporates a redesigned 3-D HD camera that is mounted on one of the four arms of the da Vinci Si surgical robot. In addition to standard real-time images of the surgical field, the camera can switch to view the images of tissue and surrounding blood vessels illuminated by the special dye when exposed to the near-infrared light.

This technique further advances the benefits of robotic surgery for better patient outcomes. Surgeons utilize computerized, highly functional mechanics and miniaturized surgical instruments to replicate every movement of their hands. The flexibility and precise movements of the instruments at the ends of three robotic arms allow both simple and more complex procedures to be done through only a few small, one-quarter-inch long incisions. Because of this, the procedure is less traumatic to the body and results in minimal scarring and faster recovery times for patients.

In 2008, NYU Langone became the first medical center in New York and New Jersey to begin using the da Vinci Si, the world's most advanced computer-assisted surgical system. With advances in computer technology and digital imaging, robotic surgery allows surgeons to treat many surgical disorders. In addition to urologic procedures, gynecologic, cardiothoracic, and general surgical procedures are also available using the advanced technology. The robotic surgery team at NYU Langone is the only multi-specialty robotic surgery program in the New York metropolitan area with two da Vinci Si surgical robots. More information about the center may be found at

About NYU Langone Medical Center
NYU Langone Medical Center, a world-class patient-centered integrated academic medical center, is one of the nation's premier centers for excellence in health care, biomedical research, and medical education. Located in the heart of Manhattan, NYU Langone is comprised of three hospitals – Tisch Hospital, a 705-bed acute-care tertiary facility, Rusk Institute of Rehabilitation Medicine, the first rehabilitation hospital in the world, with 174 beds and extensive outpatient rehabilitation programs, and the 190-bed Hospital for Joint Diseases, one of only five hospitals in the world dedicated to orthopaedics and rheumatology – plus the NYU School of Medicine, one of the nation's preeminent academic institutions. For more information visit

Tuesday, March 29, 2011

Cord Blood Cures Baby’s Grapefruit-Sized Tumor

Courtesy of Jamie Page
Harlow as a baby, and today at the age of 3

Cord Blood Cures Baby’s Grapefruit-Sized Tumor

By Jessica Ryen Doyle

Jamie Page and her husband, Ben, discussed the issue of banking their newborn’s cord blood so frequently before the birth that they finally decided if they didn’t do it, it might be the biggest regret they ever had.

“Medical advances change so quickly. Who knows when this child is 10, 20 years old if she’ll need it,” Page said. “It’s a great medical backup to have.”

It turns out the Pages, who live in Schaumburg, Ill., were absolutely right to save the cord blood.

Page had a normal pregnancy and her daughter, Harlow, was born seemingly healthy on March 19, 2008. But after two weeks, the Pages noticed she was crying a lot and seemed uncomfortable – and it just got worse.

“We were told it was probably just colic, to try different formulas, different ways of putting her to bed,” Page said. “At first I thought they were right. We must have tried six or seven different types of formula and we put gas drops in it, but she was pulling at her stomach . . . I just couldn’t put my finger on what it was.”

When Harlow was just 3 months old, her stomach became distended and she stopped having wet diapers. The Pages ended up in the emergency room, and tests revealed every parent’s worst nightmare: A grapefruit-sized mass was blocking Harlow’s kidney. Doctors quickly inserted a catheter and did a biopsy, which was sent out to several pathologists across the country.

“We were in the hospital for five or six days, letting her kidneys recover, and it was the craziest thing,” Jamie Page said. “In two days, we got four different pathologies – they all had different diagnoses. It resembled different cancers, but nothing they had ever seen before.”

There were no answers for the Pages – doctors didn’t know how to treat Harlow’s cancers, or what her prognosis was. A few pediatric oncologists in nearby Chicago decided it resembled a rare brain cancer, and it should be treated as such – so chemotherapy was the best protocol.

“We were so scared,” Page said. “My dad went through chemo for lung cancer, and it made him much more sick than helping him, we didn’t want to torture her. We just wanted her to be comfortable. At the time, doctors said she only had a few weeks to a few months to live.”

Ultimately, it was Harlow who decided for her parents. Her smile, despite how sick she was, made her parents think, ‘How can we not give this little girl a chance to fight?’

That’s when the Pages asked their doctors about a stem cell transplant. But the doctors were surprised – few families have their own supply of cord blood, they said, and it’s hard to find a match.

That’s when things started looking up for Harlow Page.

The Future of Medicine

After three rounds of chemotherapy, the doctors decided the tumor had shrunk enough for them to go in and remove it surgically, but when they cut Harlow’s abdomen open, the tumor was completely gone.

“We went in thinking she might’ve needed a hysterectomy,” Page said. “All she had left was scar tissue. They called in more surgeons to make sure they were looking in the right place. We were thrilled.”

Because the tumor was so aggressive, a stem cell transplant made sense – it was Harlow’s best option of ensuring that the tumor did not grow back. Still, she would need a double transplant.

The Pages met with the hospital's stem cell transplant team, which included Alexis Baby, a pediatric nurse practitioner.

“As of right now, there is a good prognosis,” Baby said about Harlow. “As each year passes, there is a big step toward relapse-free survival.”

So after five days of intense chemo – at higher rates than previously given – Harlow’s current cells were killed off. On the sixth day, she rested in an isolation room and on the seventh, they started the infusion. By this time, Harlow was 9 months old.

She spent 25 days in isolation to avoid any germs, but got to go home for two weeks before coming back to the hospital for her second round. Because she didn’t have enough of her own stem cells for that round, doctors had harvested her blood earlier and used that.

“As grueling as it was, she was getting her own stem cells,” Page said. “She didn’t need to be on anti-rejection pills like other kids. Some families had to worry about host vs. graft disease. We had enough concerns without worrying about her fighting her own body.”

Cord blood stem cells that are saved at birth are collected from the baby’s umbilical cord with a syringe – and the child does not feel a thing, unlike painful bone marrow extractions. Parents send the cells to a cord blood bank of their choice, where the cells can be stored indefinitely.

The price for banking cord blood varies depending on the company, but the procedure costs around $2,000 to $3,000 (this depends on whether or not you've saved the baby's cord blood tissue), plus an annual storage fee of about $125.

However, if you feel cord blood banking is too expensive an option for you, Baby urges parents to donate their newborn’s cord blood to a public bank, so it can be available for someone else who might need it.

“Otherwise, it's medical waste, and it’s just thrown away,” Baby said. “There is an option to donate it, but a lot of people don’t know about that, so it’s really unfortunate.”

Science has shown that cord blood stem cells are smarter than average cells: Once they are reinfused into the body, the cells migrate to the injured spot and immediately start the healing process.

Other advantages to using cord blood cells – besides not worrying about rejection – include the fact that the cells are younger and have not yet been exposed to any chemical or environmental factors, Baby said.

Doctors are constantly researching how cord blood can treat patients. Studies are being conducted on cord blood stem cells and their effects on brain injuries, Type I diabetes, neurology and cardiology – and that’s just the tipping point. Doctors think cord blood could be the future of medicine.

Harlow was released from the hospital in February 2009 – almost one year after she was born. Her parents had to literally teach her to swallow and eat again, because she had been nauseous for so long and had skipped solid foods. But by June 2009, she stopped taking all medications, and in September of that year, she was allowed to start attending day care.

Harlow has no recollection of being sick, and is a typical 3-year-old: She loves dancing, singing, gymnastics and watching her favorite movie, “101 Dalmatians.”

“I want to encourage other parents to save their child’s cord blood,” Page said. “I tell all our families and friends it’s the cheapest life insurance you’ll ever buy, and it’s an amazing opportunity for your child. To look at her, you’d never know, which is the best part of all.”

Monday, March 28, 2011

Strong Link Between Nicotine And Diabetes Complications

Strong Link Between Nicotine And Diabetes Complications

Scientists have reported the first strong evidence implicating nicotine as the main culprit responsible for persistently elevated blood sugar levels - and the resulting increased risk of serious health complications - in people who have diabetes and smoke. In a presentation at the 241st National Meeting & Exposition of the American Chemical Society (ACS), they said the discovery also may have implications for people with diabetes who are using nicotine-replacement therapy for extended periods in an attempt to stop smoking.

"This is an important study," said Xiao-Chuan Liu, Ph.D., who presented the results. "It is the first study to establish a strong link between nicotine and diabetes complications. If you're a smoker and have diabetes, you should be concerned and make every effort to quit smoking."

Nearly 26 million people in the United States and 260 million more worldwide have diabetes. Those complications - which include heart attacks, stroke, kidney failure, and nerve damage - are why diabetes is the sixth leading cause of death in the United States, and the third leading cause in some minority groups, according to the National Institutes of Health. Treating those complications takes $1 out of every $10 spent on health care each year.

Liu cited past research showing that good control of blood sugar levels is the key to preventing complications. The gold standard for monitoring long-term blood sugar levels in people with diabetes is the hemoglobin A1c (HbA1c) blood test. Used in conjunction with daily home blood sugar monitoring, the HbA1c test reveals the average amount of sugar in the blood during the last several weeks. High test results mean that diabetes is not well controlled and there is an increased risk of complications.

Doctors have known for years that smoking increases the risk of developing complications. Studies also show that smokers with diabetes have higher levels of HbA1c than nonsmokers with diabetes. However, nobody knew the exact substance in cigarette smoke responsible for the elevation in HbA1c. Liu and colleagues suspected it may be nicotine and set out to check nicotine's effects on HbA1c. Using human blood samples, they showed that concentrations of nicotine similar to those found in the blood of smokers did, indeed, raise levels of HbA1c.

"Nicotine caused levels of HbA1c to rise by as much as 34 percent," said Liu, who is with California State Polytechnic University in Pomona, Calif. "No one knew this before. The higher the nicotine levels, the more HbA1c is produced."

Doctors could use data from this study as a new basis for encouraging patients with diabetes to quit smoking, Liu said. What about nicotine patches, electronic cigarettes, and other stop-smoking products? Liu pointed out that people tend to use those products for only brief periods, and that the benefits of permanently stopping smoking may outweigh any risk from temporary elevations in HbA1c. However, the study may raise concern over the long term use of such products, he added.

Source: American Chemical Society 

Sunday, March 27, 2011

7 Major Advances Predicted for Health & Medicine in 2011

7 Major Advances Predicted for Health & Medicine in 2011

In terms of advancement in the fields of science and medicine, 2010 was a stellar year. German doctors appeared to have cured a man of HIV. Doctors watched a drug called PLX4032 melt away the tumors of melanoma patients who otherwise were out of treatment options. And scientists created the first "synthetic life."
What significant advances can we expect in 2011? Here are seven predictions, provided by experts in these fields who gave MyHealthNewsDaily the lowdown on what might promote our health next year.
Prediction 1: Restaurant menus that list calories will help us cut our daily total.
This year the nation will follow New York City in requiring restaurant chains to post calorie counts next to standard menu items. The mandate comes as part of the Patient Protection and Affordable Care Act, and requires chains with 20 or more locations to list calories by spring 2011.
Physicians who specialize in weight loss say the move will help some who don't realize their latte has 300 calories, or that their favorite dish might pack more than 1,000 calories. But the doctors aren't predicting whether it will make a dent in the nation's obesity rate. [Related: 11 Surprising Things That Can Make Us Gain Weight]
"I don't think people care. If they did, they wouldn't be going to these stores, because they all know what they are," said Dr. George Fielding, of New York University's Langone Medical Center.
The mandate also requires the listing of calories in vending machines and "similar retail food establishments," according to the FDA.
"I think it might help," said Dr. Lee Kaplan, director of the Massachusetts General Hospital's Weight Center. But realistically, the effect "is going to be quite modest."
However, Kaplan added, "I think the risk of doing this is essentially zero, and the benefit is undetermined. But with so little risk, I think we ought to do it."
Prediction 2: Results of a promising HIV vaccine will be announced.
An American man made international headlines this month when German doctors announced he  had been cured of the virus that causes AIDS. The HIV-positive man had suffered from acute myeloid leukemia — a deadly blood cancer — so in 2007 the doctors performed a bone marrow transplant to treat the leukemia. They were lucky enough to find a bone marrow donor with a rare mutation, called Delta 32, that providesnatural resistance to the human immunodeficiency virus.
Three years after the transplant, the man continued to show no signs of HIV.
But for all the media attention to this case, another scientific advance is likely to help more people battle HIV and AIDS in 2011.
In 2009, studies in Thailand showed a vaccine could reduce the risk of contracting HIV by about 30 percent. Dr. Susan Zolla-Pazner, an HIV researcher at the New York University Langone Medical Center in New York City, said it was the first sign of real success for an HIV vaccine, and a guide to future research.
"It was the first and only light in a very dark tunnel that suggested that we were beginning to get off of home plate in terms of making any progress," Zolla-Pazner said.
Reflecting on the case of the German achievement, Zolla-Pazner pointed out that only a tiny fraction of HIV patients would be able to find matching bone marrow from a naturally resistant donor, and even then, those patients would risk dying from the bone marrow transplant procedure.
"It shows that, in theory, with bone marrow transplants, you can cure [HIV], which is interesting. But certainly it is not anything that could be applied even on a small scale, let alone on a vast scale with millions of people," Zolla-Pazner said.
So instead of bone marrow transplants, Zolla-Pazner is setting her hopes on HIV vaccine advancements.
"If there's a clear answer about what that vaccine did to provide protection, it provides a foundation to build another vaccine," she said.
Zolla-Pazner said more results based on the experimental vaccine are expected to be announced in mid-2011.
Prediction 3: Many broken hearts will be fixed by freezing them.
The 2.2 million people in the United States afflicted with atrial fibrillation will see another tool in the fight against their condition in 2011: a device that freezes heart tissue.
A healthy heart contracts under a timed pattern of electrical signals, but people with atrial fibrillation have irregular electrical signals, causing the upper chambers of their heart to quiver instead of beat, according to the American Heart Association. Atrial fibrillation can lead to fatigue, shortness of breath, and even stroke.
This month the Food and Drug Administration approved the Arctic Front cardiac cryoablation catheter system device, which freezes sections of heart tissue instead of burning them with radio-frequency energy. Doctors can use the device to purposefully scar certain sections of the heart, blocking the irregular signals that create atrial fibrillation.
"This treatment model has shown to cure this disease in 70 percent of patients," said Dr. Moussa Mansour, who used the device in clinical trials at Massachusetts General Hospital in Boston.
"The old way [radio-frequency ablation] had a similar range of success, but we believe it is easier to do it in the new way," Mansour said.  Now that the cryoablation technique has been approved, he added, more people will receive therapy.
Prediction 4: The lowered bar for lap-band surgery will have an impact on the decisions made by millions of obese Americans.
Surgery is one of the more controversial solutions to the nation's obesity problem, even though research shows stomach surgery for weight loss is sometimes the most effective treatment.
This coming year will open up the option of bariatric weight-loss surgery to millions more Americans. Until recently, only people with a body mass index (BMI) of at least 40, or those with BMIs of 35 and higher with another serious health problem related to their obesity, were candidates for lap-band surgery from Allergan, according to the FDA. In the lap-band procedure, a doctor places an inflatable silicon ring around the upper portion of the stomach and constricts it.
In late 2010, the FDA voted to change the eligibility criteria for the Allergan procedure. Now, most people with a BMI of 35 or higher, and patients with a BMI of 30 or higher who also have another  serious medicalcondition, can undergo the operation.
"Only one in 50 people will keep 50 pounds off for one year using diet and exercise. It's just a profound waste of time for people who are obese," said Fielding, who is an advocate of the surgery.
"Surgery does work, it's just so well established," he said. "All around the world, no matter what method you use, you can see results."
Fielding noted that if a person with diabetes and a BMI of 30 loses 50 pounds and keeps it off, he has an 80 percent chance of coming off their diabetes medications. "There are millions of people, literally, with the BMI of 30 and 35 who have diabetes," he said.
But physicians who specialize in weight loss warn about the dangers of opening a patient’s body when there are other options.
"The issue with surgery, any kind of surgery — banding, bypass, etc. —  is they work, by far, better than anything else. The problem is that they are surgery, so they're invasive," Kaplan said. "They have risks associated with them."
Kaplan said only 2 percent of patients who meet the criteria for weight-loss surgery actually undergo the procedure, in part because of the risks. Because of this, he doesn't think dropping the criteria by 5 BMI points will drastically change the odds of an obese person submitting to the procedure.
Kaplan acknowledged that research on people who’ve had weight-loss surgery has contributed to the understanding of exactly how the body can lose weight — or keep it on.
"We're learning an enormous amount from surgery, even though surgery itself is used infrequently," Kaplan said. Doctors used to think weight-loss surgery worked by making the stomach smaller, but they have found evidence that the surgery actually changes physiological mechanisms in the body that eventually determine whether or not a person gains weight, he said.
Prediction 5: School lunches will get a makeover that will lower obesity in the next generation.
More than about any surgery, obesity experts are excited about the Healthy, Hunger-Free Kids Act, which takes effect in 2011.
The new legislation raises the federal reimbursement rate for school lunches by 6 cents per meal, according to the American Academy of Pediatrics. The bill will allot an additional $4.5 billion toward school lunch programs over 10 years, and it has tasked the U.S. Department of Agriculture with creating nutrition standards for food sold through vending machines in schools.
"If you can tell a kid at age 5 or 6, ‘Look, this food is really yummy — it just doesn't come from McDonald's, it's just fresh food,' then you've got a chance," Fielding said. "Once a kid is fat and 10 or 12 years old, it doesn't matter how much you're going to tell them, it's hot air."
"You can make the next generation have a chance by teaching them about healthy food," he said.
Kaplan called the legislation "terrific. "
"When the [school lunch] program was developed 50 years ago, the focus was not on obesity, it was on malnutrition," Kaplan said. "Now … we see obesity is an even bigger problem than malnutrition."
Prediction 6: Genomics will find medicines that work for you.
Sequencing an entire human genome cost about $3 billion a decade ago. Last year it cost around $10,000, according to Dr. Eric Topol, director of the Scripps Translational Science Institute in La Jolla, Calif.
Topol said he expects to see the price drop again in 2011, to about $4,000. And with lower financial barriers, he said, more medical advances from genomic research will come in the next year.
"This field is exploding," he said.
For example, Topol said, last year pharmacy benefit managers Medco and CVC/Caremark started examining the genes of patients on the widely used heart drug Plavix. The researchers identified two genes — called PON1 and CYP2C19 — that can determine how a person would respond to Plavix.
"These two genes explain why this drug, which is the second biggest drug in the world, is so inconsistent," Topol said. "Two-thirds of patients on Plavix do well, but the others either don't see the drugs’ effects and/or suffer from side effects."
Genotyping has already found mutations that would determine a person's response to malaria drugs, blood thinners, and breast cancer therapy, Topol said.
For the hepatitis C drug interferon, Topol said, researchers have identified genes that could save about half of all hepatitis C patients from side effects.
"Fifty percent of people don't respond [to interferon], and that drug costs $50,000 and it makes you sick," Topol said. "That is a really striking example.”
Genetic analysis “saves lots of money; it saves patients from being sick for years with a drug that doesn't help them."
Prediction 7: Genomics will help us understand cancer.
Topol predicted the low cost of genome sequencing will also bring good news in cancer research next year, "because the sequencing is becoming so much cheaper and fast, and because bioinformatics is getting more advanced," he said.
With faster technology, Topol said it's become increasingly feasible for cancer researchers to compare a person's genome — the "germ line" genome the patient was born with — with the mutated genome of his or her cancerous tumors, to find the genes that are driving the cancer. In other words, they’ll find the genes that are making cancerous cells act cancerous.
Topol said such research has already benefited melanoma patients taking the powerful drug PLX4032. Genomic research has showed melanoma patients with tumors that have what's known as a BRAF mutation will benefit from the drug, while patients whose tumors don't have that mutation will likely get worse with the drug.
Topol said similar research is "just going to get better" in 2011.

Saturday, March 26, 2011

Gene Therapy for Parkinson's Advances

Gene Therapy for Parkinson's Advances

Brain surgery to insert genetic cargo improves movement for some

Using brain surgery to insert replacement genes, doctors can alleviate some movement problems in people with Parkinson’s disease. While not all of the gene therapy recipients in a new study improved, the group on average registered tangible gains after getting a gene that revs up production of a much-needed neurotransmitter, researchers report in an upcoming issue ofLancet Neurology.
Click here to find out more!
Notably, none of the patients had significant side effects attributable to the therapy.
“The pendulum on gene therapy has really swung back and forth,” says study coauthor Matthew During, a physician and neuroscientist at Ohio State University in Columbus. “It was enormously hyped at first.” But the death of a patient in Philadelphia in 1999 and the appearance of leukemia in children in France getting gene therapy for an immune disorder—leading to a temporary suspension of trials in 2003—stalled the research. “The field languished for a while,” During says.
But he and his colleagues have continued to pursue the technology, using a disabled, nonpathogenic virus as the delivery vehicle for potentially useful genes. To treat Parkinson’s disease, the team has targeted a troublesome part of the brain where signaling gets obstructed in patients with the neurological disorder.
In the new study, the researchers randomly assigned 16 patients with advanced Parkinson’s to undergo an operation to install gene replacements; 21 similar patients got sham surgery and received no genes. Neither group was told which operation they were getting.
Doctors measured each patient’s physical movement before surgery, using a standard scoring formula for Parkinson’s patients. Six months after surgery, the patients given gene therapy showed an average improvement of 23.1 percent in their scores, compared with a 12.7 percent improvement among the sham surgery group. The formula measures problems such as freezing up, tremors and uncontrolled movements.
“This experiment was extremely well constructed and well designed,” says Michael Hutchinson, a neurologist at New York University who wasn’t involved in the trial. “This seems to be a positive effect, but not a clinically big effect.” Even so, he says, it clears the way for a larger study with more patients and possibly larger doses of the gene therapy.
The therapy zeroes in on a brain region called the subthalamic nucleus. While its normal role is poorly understood, this region becomes overactive in Parkinson’s patients, blocking signals that regulate muscle movement. Parkinson’s patients lack a brain-signaling molecule called dopamine, and that shortage results in the loss of another neurotransmitter called GABA in the subthalamic nucleus, triggering overactivity there.
The experimental therapy delivers a gene encoding an enzyme that boosts GABA production in the subthalamic nucleus. When it works, the gene therapy calms this region and smooths the flow of messages in the brain by allowing signals governing muscle movement to be shuttled through the nearby thalamus, Hutchinson says.
Another Parkinson’s treatment, called deep brain stimulation, uses an implanted electrode to quiet the subthalamic nucleus (SN: 1/31/09, p. 13).
The placebo effect seen in the people getting sham surgery is a curiosity not uncommon in Parkinson’s treatment, During says. Just getting the operation, in which “burr holes” are drilled into both sides of the skull under light sedation, stimulates optimism in the patient and results in a rise in dopamine production, alleviating some symptoms, he surmises.
During, who teamed with study coauthor and neurosurgeon Michael Kaplitt of Weill Cornell Medical College in New York City and others on the study, says a larger trial is planned. Meanwhile, people who got the sham surgery in this trial are now being offered the gene therapy.
Some patients from an earlier safety trial of this gene therapy are still showing sustained improvement; one is now seven years post-surgery. “It appears the clinical benefit persists,” says During, and that the transferred genes continue to help calm the overactive subthalamic nucleus. He and Kaplitt are cofounders of Neurologix, a biotechnology company based in Fort Lee, N.J., that financed this trial and makes portions of NLX-P101, the gene therapy medication.

Friday, March 25, 2011

Sex Increases Heart Attack Risk for Lazy People

Researchers at Tufts Medical Center in Boston say sedentary people who suddenly have sex or exercise have an increased chance of a heart attack.

Sex Increases Heart Attack Risk for Lazy People

If you sit on your butt most of the time, this news may make you break out in a sweat: Sporadic bursts of sex or exercise can increase the risk of a heart attack.

Dr. Issa Dahabreh and Dr. Jessica Paulus, researchers at Tufts Medical Center in Boston, made this discovery after reviewing 10 studies investigating physical activity, three involving sexual activity and one study that looked at both.

The study, which appears in the latest issue of theJournal of the American Medical Association, came to a painful conclusion: Acute cardiac events were significantly associated with episodic physical and sexual activity.

However, that was only in people who could be classified as "couch potatoes," "lard bottoms" and "lazy bones."

"We want to make that clear," Paulus told AOL News. "The point isn't that sex or exercise is bad, it's that you need to have a regular physical routine."

She emphasized that even among the most sedentary people, the increased risk of cardiac arrest after exercise or sex only lasts one to two hours.

One frustrating aspect of the study: The research didn't go into detail as to what kind of sexual activities are most likely to increase the risk.

One person not surprised by the results is porn actress Nina Hartley, who also is a registered nurse (although her license is currently inactive).

"This lets us know that sex is great exercise, so people should get their heart checked out and start having more sex," she said.

Thursday, March 24, 2011

Medical students to get hands on experience with new FAKE breast

Test: Dr Pugh hopes the simulator breast will be able to pick up how accurately medical students examine women

Medical students to get hands on experience with new FAKE breast that can simulate tumours

Student doctors are set to get a more hands-on experience when learning how to conduct breast examinations.

That’s because a new synthetic bust has been developed by scientists with sensors that can measure the accuracy of the examination, as well as simulating tumours.

In time doctors hope it will become a standard part of a medical students’ learning, something which they are not currently tested on.

Dr. Carla Pugh of Northwestern University who is developing the technology said: ‘What if there were a test and you had to meet a minimum level of proficiency before you could do breast exams and say you're competent?’

She added that doctors don't want to talk about breast examinations, but they all know a colleague who's missed a cancer during a check-up.
Getting to grips: Dr. Carla Pugh demonstrates one of the sensor-enabled breast models she's developed
Getting to grips: Dr. Carla Pugh demonstrates one of the sensor-enabled breast models she's developed
Working with a group of experts in mechanical engineering, computer science, statistics and medical education – with a $1.8million federal grant – she hopes to replicate the success of a prosthetic pelvis they developed.

But, while the technology may be expensive, some of the ‘fake tumours’ are made from nothing more than beans glued together, glass beads and hardened clay.
Lentils embedded in rubber mimic the feel of fibrocystic breast changes, a noncancerous condition.

Dr Pugh said: ‘Any material I encounter on a daily basis is fair game to help me build a patient.’

In 2009, the U.S. Preventive Services Task Force recommended against teaching women how to do breast self-exams, finding little evidence they reduce breast cancer death rates.

The task force added that techniques used in breast exams are not standardised enough, but can detect a large proportion of cancers if done well.

Many groups, including the American Cancer Society, still recommend women get regular breast exams from their doctors.
Testing medical students' breast exam skills with a sophisticated simulator would be an important advance, says Dr. James Gordon, who directs the Gilbert Program in Medical Simulation at Harvard Medical School. He's not involved in Pugh's research.

Lumps: The fake breasts are filled with 'tumours' and lumps made from lentils, beans and clay
Lumps: The fake breasts are filled with 'tumours' and lumps made from lentils, 
beans and clay

Simulators used in medical education have been rapidly evolving over the past decade but working with real human beings will continue to be at the core of medical education, Dr Gordon says.

The newest models are fitted with sensors that can give students feedback on whether they are doing an exam properly or not.
    Familiar with another Pugh device, a pelvic exam simulator, Gordon says Pugh's work is at the forefront of the field.
    ‘She's at the cutting edge and does some of best work in the world in creating and validating simulators that students and medical professionals could use,’ Gordon says.
    The current prototype, a disembodied plastic breast hooked by wires to a computer, modestly wears a blue cloth covering when not being examined.
    Despite a $1.8million federal grant to develop the prosthetic breasts, doctors find the most realistic way to recreate tumours is with household products
    Despite a $1.8million federal grant to develop the prosthetic breasts, 
    doctors find the most realistic way to recreate tumours is with household products

    ‘Because it's a human being,’ Pugh explains when asked about the covering. ‘She's sitting there on the table with her breast exposed, so when we're not examining her we cover her. It's a habit that we've formed.’

    Breast exam skills aren't tested in the current U.S. medical licensing exam, says Dr. Stephen Clyman of the National Board of Medical Examiners, a co-sponsor of the test that's the entryway to the medical profession.

    Clyman directs the board's Center for Innovation, which investigates how new technology might be used in future licensing exams.
    He is a consultant on Pugh's breast exam simulator research.

    Deciding how to score a breast exam using a simulator in the high-stakes licensing exam would be challenging, Clyman says.
    ‘Is it just a matter of finding a lump?’ he asks. ‘Or are you concerned about whether somebody palpates by accepted protocol when you know that many doctors don't follow the accepted protocol?’

    Pugh's project will attempt to answer those questions by recording the movements, pressure and patterns of experienced doctors as they palpate simulator breasts with various masses and cysts hidden inside.

    The next step is testing the mock-up on experienced doctors. A meeting of cancer doctors in Chicago in June is the next test run.