The latest medical advances from Johns Hopkins Medicine


A Message to Older Adults: Don't Fear the Effects of Sensible Exercise
 
A Johns Hopkins study should ease the concerns held by many older adults with mild high blood pressure about the strain or harm exercise could cause their hearts. Results of the research on 104 men and women age 55 to 75 showed that a moderate program of physical exertion had no ill effects on the heart's ability to pump blood nor does it produce a harmful increase in heart size. In this study, "moderate" translated to sustained exercise for about an hour, three times a week.

The Johns Hopkins study is believed to be the first to evaluate the effects of exercise on the heart's ability to function, to pump and to fill up with blood.

"Exercise is a highly effective means of increasing the heart's efficiency and reducing body fat, factors that may ward off future health problems, such as heart disease and diabetes", says lead study investigator and exercise physiologist Kerry Stewart, Ed.D., a professor of medicine and director of clinical and research exercise physiology at The Johns Hopkins University School of Medicine and its Heart Institute.

Not only were there no ill effects sustained, despite periodic increases in blood pressure during the workout, Stewart and his team reported, but results also suggest that the exercise producing these effects benefited the hearts of those who made the most gains in physical fitness and for those who lost the most abdominal fat.

For a six-month period, the Johns Hopkins team assessed the benefits of a supervised program of exercise training in a group of 104 older men and women, measuring heart function, and body fitness and fat levels at the start and end of the study. All of the participants were in general good health except for untreated, mild hypertension.

The group that was not exercising had either no or significantly less improvement than the exercising group. Special scans, using an X-ray machine, were used to assess total body fat.

"Making gains in body fitness and losing abdominal fat are truly important to the long-term health of the heart," says study co-author and cardiologist Edward Shapiro, M.D., a professor at Johns Hopkins. "Our results confirm that moderate-intensity exercise can have many health benefits - including gains in heart function that are linked to increased fitness and reduced fatness.

"Our study also shows that the vast majority of older people with mildly elevated blood pressure can benefit from moderate exercise, and they should talk about it with their physician to determine an appropriate exercise and any other options for treatment", completes Shapiro.
 
Hopkins Scientists Use Stem Cells to "Build" Motor Neuron Circuits
 
In a dramatic display of stem cells' potential for healing, a team of Johns Hopkins scientists reports that it has engineered new, completed, fully working motor neuron circuits -- neurons stretching from spinal cord to target muscles -- in paralyzed adult animals.

"It's a remarkable advance that can help us understand how stem cells can begin to fulfill their great promise," says Douglas Kerr, M.D., Ph.D., a neurologist who led the Johns Hopkins team.

The researchers created what amounts to a cookbook recipe to restore lost nerve function, Kerr explains. The approach could one day repair damage from such diseases as ALS (Lou Gehrig's disease), multiple sclerosis or transverse myelitis or from traumatic spinal cord injury, the researchers say.

The Johns Hopkins team says 11 of the 15 treated rats gained significant, though partial, recovery from paralysis after losing motor neurons to an aggressive infection with Sindbis virus -- one that, in rodents, specifically targets motor neurons and kills them. The animals recovered enough muscle strength to bear weight and step with the previously paralyzed hind leg.

Kerr says: "Paralysis is like turning on a light switch and the light doesn't go on. The connectivity is messed up but you don't know where. We've asked stem cells to go where needed to fix the circuit."

Of some 4,100 new motor neurons created in the spinal cord, roughly 200 exited the cord and 120 reached skeletal muscle, forming typical nerve-muscle junctions, with appropriate, typical chemical markers. Microscopically, the neurons and their muscle associations appear identical to natural ones in healthy animals.

Research begins this summer to see how well the technique applies to human nerve recovery, using federally-approved human ES cells in larger mammals like pigs, Kerr says. There are still major questions to be answered regarding safety and effectiveness. Questions of tumor-formation, often a concern with ES cells, of the safety of surgery and of the ES cells' ability to form healthy motor circuits are major questions to answer. Several years of testing and thorough data evaluation would occur before applying to the FDA to approve human clinical trials.
 
Heat Therapy for Cancer May Be Key to "Lance Armstrong Effect"
 
Experts at Johns Hopkins have linked scientific evidence to suggest an explanation for why testicular cancer patients like seven-time Tour de France winner Lance Armstrong survive far better than patients with other advanced cancers.

Heat sensitivity may make testicular cancer cells more susceptible to standard treatments and die off more readily.
"The warmer the region of the pelvis, the more unstable the nuclear matrix is in the cells of that region, and prone to death," says Theodore DeWeese, M.D., professor and director of the Department of Radiation Oncology and Molecular Radiation Sciences. The nuclear matrix, found in the nucleus of all cells, was first discovered in the early 1980s by a team of Johns Hopkins scientists and shown to be heat-sensitive by researchers at the Washington University in St. Louis.

"Cancer cells already have unstable nuclear matrices. If we give a cancer cell more heat to completely disrupt its matrix, and then add toxic drugs and radiation, the cancer cell may be so disabled that it won't be able to replicate and will die."

Heat therapy is already used in a handful of cancer centers around the country, and has been applied for thousands of years as an ancient cure-all for ailments ranging from back pain to arthritis. Although people flock to hot baths and springs to immerse their entire body, the Hopkins trio believes that selectively heating cancer cells may not only be more effective, but also prevent matrix damage in normal tissues.

To direct heat only to cancer cells, the researchers are investigating the use of nanoparticles that have an affinity for surface proteins carried by cancer cells. Once the nanoparticle finds the correct "address" of the cancer cell, it slips through the cell's surface and heats the cell from the inside out after exposure to a magnetic field.

The Johns Hopkins scientists believe that, if injected through the bloodstream, magnetic nanoparticles may be able to reach tumors throughout most of the body. And as long as the nanoparticles penetrate most of the cells in the tumor, the temperature increase will spread to the entire mass.

Preliminary research is under way at Johns Hopkins to refine heat-delivery-systems and test them in prostate cancer animal models.
 
Antioxidants May Slow Vision Loss
 
Scientists at Johns Hopkins have successfully blocked the advance of retinal degeneration in mice with a form of retinitis pigmentosa (RP) by treating them with vitamin E, alpha-lipoic acid and other antioxidant chemicals.

"Much more work needs to be done to determine if what we did in mice will work in humans," said Peter Campochiaro, the Eccles Professor of Ophthalmology and Neuroscience at The Johns Hopkins University School of Medicine. "But these findings have helped to solve a mystery."

In patients with RP, rod photoreceptors die from a mutation, but it has not been known why cone photoreceptors die. After rods die, the level of oxygen in the retina goes up, and this work shows that it is the high oxygen that gradually kills the cones. Oxygen damage is also called "oxidative damage" and can be reduced by antioxidants. So for the first time, scientists have a treatment target in patients with RP, added Campochiaro.

Retinas in all mammals, from mouse to man, are made up of light-sensitive cells known as cones and rods, named for their shapes, which convert light into nerve signals that are then transmitted to the brain via the optic nerve. In diseases like RP and age-related macular degeneration (AMD), these cells die off and eventually lead to blindness (in the case of RP) or legal blindness (in the case of AMD).

Campochiaro and his team injected the mice with vitamin E, vitamin C, alpha-lipoic acid or an antioxidant similar to superoxide dismutase. In mice that received vitamin E or alpha-lipoic acid, 40 percent of the cones survived, about twice as many as in the control group or the groups treated with the other antioxidants, which had no identifiable effect.

"These experiments suggest that an optimized regimen of antioxidants may help to protect patients with retinitis pigmentosa", says Campochiaro. He emphasizes that even if found valuable, antioxidant treatment of RP, a group of inherited blinding diseases with complex genetic roots, would not cure the disease. But the salvaging of cones are critical to central vision, and the treatment could serve as a "maintenance therapy," he said. "That alone would be an enormous help."

Antioxidants naturally occur in some fruits and vegetables, and are available as supplements, but Campochiaro said it remains unclear whether the amounts of antioxidants consumed in foods provides any benefit to people with these types of vision impairments.
 

 
Johns Hopkins Hospital Ranked as #1 for 16 Consecutive Years
 
For the 16th year in a row, The Johns Hopkins Hospital has topped U.S. News & World Report's annual Rankings of American Hospitals. For a complete list and methodology of rankings, please visit www.usnews.com

Johns Hopkins Hospital ranked in the top 10 in 15 of the 16 speciality categories listed. In addition to landing at the top of the honor roll, The Johns Hopkins Hospital had the following rankings:

#1
Ear, Nose & Throat (Otolaryngology)
Gynecology
Kidney Disease
Rheumatology
Urology


#2
Neurology/Neurosurgery
Ophthalmology (Wilmer Eye Institute)
Psychiatry

#3
Cancer
Digestive Disorders
Heart/Heart Surgery
Hormonal Disorders (Endocrinology)
Pediatrics
Respiratory Disorders

#4
Orthopedics

#17
Rehabilitation
 
Maryland Supports Stem Cell Reseach
 
The members of a new state stem cell research commission were announced by Maryland's Governor, Robert Ehrlich, who promised science will dictate which research in the politically sensitive area will get funded.

Federal funding of embryonic stem cell research, which supporters say holds the promise of treating or curing a number of diseases, has been sharply restricted by President Bush. In response, Maryland and other states have approved funding for stem cell research, including embryonic stem cells.

Embryonic stem cells are master cells that can form every other cell in the body and because of that ability researchers say they may lead to cures and treatments for a number of diseases, conditions and injuries. While adult stem cells also exist, researchers say they are more limited.

Obtaining embryonic stem cells for research kills the embryo they are taken from, which is opposed by many conservative religious groups. Supporters say the stem cells can be obtained from unused embryos created for in vitro fertilization that would otherwise be destroyed.

Maryland is among a number of states that have voted to fund stem cell research on their own follow Bush's decision.

California has dedicated the most, with a $3 billion stem cell research institute, which is being challenged in court by opponents of embryonic stem cell research.
 
The Next Era for Johns Hopkins Medicine
 

Confetti rained down on the nearly 250 people gathered in The Johns Hopkins Hospital's Houck Courtyard as the centerpiece of the largest and most expensive hospital project in Maryland's history was officially unveiled. Two new clinical buildings will move Johns Hopkins Medicine, and American medicine, far into the future.

University President William R. Brody, Johns Hopkins Medicine CEO Edward D. Miller, JHH President Ronald Peterson and other top administrators were present to celebrate the groundbreaking of the Cardiovascular and Critical Care Tower and the Children's Tower, two buildings that will form the new face of the hospital.

The masters of ceremonies for the event were George Dover, the Given Foundation Professor of Pediatrics and director of the Department of Pediatrics at the School of Medicine, and William A. Baumgartner, the Vincent L. Gott Professor of Cardiac Surgery, cardiac surgeon in charge at the hospital and vice dean for clinical affairs at Johns Hopkins Medicine.

The new clinical towers are part of the comprehensive 10-year master plan that will transform the medical campus. Construction on that project is expected to get under way in early 2007, with a completion date scheduled for 2008-2009.
 

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