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CLINICAL NEWS |
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A Friendly Reminder for HIV Patients
A pocket-size device giving electronic-voice reminders to "take your medicine" proves to be a success for people living with HIV whose memory is slightly impaired by the virus.
Researchers at Johns Hopkins report that the device, dubbed "Jerry" by most users, is a portable gadget programmed to ease the task of taking medicines in multiple doses every day on time. HIV-infected patients, particularly those
suffering from mild memory loss from the disease, benefit highly from Jerry's friendly reminders, according to a study published in the Sept. 15 issue of the journal Clinical Infectious Diseases.
Like an alarm clock, Jerry, more properly known as Disease Management Assistance System (DMAS), flashes a light and verbally tells the patient the exact dosage and medication to take at the correct time. DMAS is rechargeable and weighs
about as much as a cell phone. Its computer programming keeps track of the patient's compliance, allowing the doctor to download and print a report for monitoring the patient's adherence to the medication schedule.
"One of the biggest reasons HIV patients cite for not taking their medication is just plain forgetfulness," says Adriana Andrade, M.D., M.P.H., assistant professor at Division of Infectious Diseases. "We thought a verbal reminder would be
the best possible solution."
"On average, HIV-infected, treatment-naïve patients today take roughly two pills once a day, a significant decrease from a few years ago, when patients had to juggle dozens of medications per week," says Andrade. "But with all the
regimens, patients must adhere to their medication faithfully because the virus easily develops a resistance, more so than most infectious diseases."
Fifty-eight of 64 patients completed the four-month study. Half of the patients were given a Jerry device and attended adherence counseling sessions, while the other half received only counseling. Those with Jerry took their medication 80
percent of the time, while those without did so only 65 percent of the time.
"Hopefully, other devices like the DMAS will be further evaluated in similar studies, while incorporating the recent technologies of the two-way pager, cell phones or special alarm clocks," says Andrade.
The DMAS used in this study was manufactured by Adherence Technologies.
Funding was provided by grants from the National Institutes of Health, the Johns Hopkins Hospital General Clinical Research Center and Merck Laboratories.
On the web:
www.hopkins-aids.edu
Modified Collagen Could Yield Important Medical Applications
Collagen often pops up in beauty products and supermodel lips. But by mating collagen with a molecular hitchhiker, materials scientists at Johns Hopkins hope to create some important medical advances. The researchers have found a simple
new way to modify collagen, paving the way for better infection-fighting bandages and a treatment to block the formation of unwanted scar tissue. In addition, tissue engineers may be able to use modified collagen in the lab to help control
the formation of tiny new blood vessels that can be used to promote the integration of tissue implants in patients.
The research focuses on the human body's most common protein. Collagen promotes blood clotting and provides the sponge-like scaffold upon which cells build nerves, bones and skin. Because it is non-toxic, dissolves naturally over time and
rarely triggers rejection, collagen is commonly used in cosmetics, drug delivery systems and biocompatible coatings.
"This new modified collagen opens the door to new medical treatments, because it is easy to attach bioactive agents to certain peptides," says Michael (Seungju) Yu, an assistant professor in the Department of Materials Science and
Engineering of Johns Hopkins University.
"When the peptides bind with collagen, these attached agents can dramatically change the way collagen behaves in the body. For example, collagen normally attracts cells to close up a wound and form scar tissue, which can lead to dangerous
clots inside a blood vessel or at certain injury sites, where scar tissue can interfere with the formation of new nerve connections. However, in our lab experiments, the modified collagen followed a different course. It actually repelled
cells instead of attracting them. When we added human cells to a lab dish, the cells migrated toward an untreated collagen film but avoided the modified collagen sample. This form of collagen could stop the formation of blood clots and
scar tissue", Yu explains.
Still other medical uses are possible. A growth factor joined to collagen could encourage new cells to multiply. An antibiotic attached to collagen could help a collagen-based bandage fight infections over a long period of time. Modified
collagen could also release helpful medications while serving as a coating for surgical tools and implants.
"With this process," Yu said, "we can make the collagen that's already found in the human body behave in new ways, including some ways that are not found in nature. Modified collagen can give us great new tool for treating injuries and
illnesses."
Yu's research is supported by grants from the National Science Foundation and the National Institutes of Health. |
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RESEARCH NEWS |
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Dual-Drug Therapy Targets Colon Cancer Gene
Johns Hopkins Kimmel Cancer Center scientists have found that interferon, used for 30 years to treat blood cancers, multiple sclerosis and hepatitis, selectively kills colon cancer cells when combined with another standard chemotherapy
agent. New studies suggest that the combination tactic, which targets a common gene pathway in colon cancer cells, could be more potent than either drug alone, and has fewer side effects.
"Instead of killing a tree by chopping it down, this approach focuses on cutting off the diseased branch, leaving the rest of the tree relatively unscathed," says Betsy Barnes, Ph.D., assistant professor of oncology and lead
researcher.
By itself, interferon's cell-killing activity is non-specific in targeting a variety of cells and cell-based gene activity, causing serious side effects such as heart failure and low blood counts, in addition to killing cancer cells. But
scientists found one factor in interferon's makeup that could have cancer-killing qualities, but with fewer side effects since it activates fewer genes.
The team found that IRF5 (Interferon Regulatory Factor-5), which works as a tumor suppressor to halt cancer cell growth, is turned off by many cancers, but low levels of the suppressor protein are found in most colon cancers. To boost IRF5
levels, the investigators combined interferon with a chemotherapy drug called irinotecan (CPT-11), a drug that damages DNA in rapidly dividing cells, rendering them unable to divide.
To demonstrate their theory that IRF5 is a key ingredient in the dual-drug therapy, the scientists tested various combinations of the drugs in colon cancer cell lines, with or without IRF5. Irinotecan alone causes 65 percent cell death in
lines with IRF5 proteins present. Knock out IRF5 proteins and cell deaths drop to 37 percent. When the investigators combined irinotecan and interferon, more than 80 percent of colon cancer cells with IRF5 proteins died.
"Not only does the combination of these drugs involve fewer gene activations, it may allow use of smaller amounts of both drugs and limit side effects," says Betsy Barnes, Ph.D., assistant professor of oncology and lead researcher.
It is not clear whether the combination therapy would work in other cancers, since IRF5 is absent in a number of blood cancers. But since colon cancer is the third deadliest cancer in the United States, Barnes and her team will conduct
further tests in genetically modified mice and potentially create a new strategy to treat the disease.
Colon cancer strikes more than 100,000 people in the United States annually and kills more than 56,000.
Funding for this research was provided by the American Cancer Society and a Flight Attendant Medical Research Institute Young Clinical Scientist Award.
On the web:
www.hopkinskimmelcancercenter.org
MRI used to map "silent" heart changes that "remodel" the heart
Using MRI to tag the work of millions of individual strands of heart muscle fibers, researchers at Johns Hopkins have successfully mapped the smallest deformations inside the beating hearts of 441 middle-aged and elderly men and women who
have either silently developed heart disease or remained healthy. The novel use of the MRI allowed the researchers to create a gridlike, three-dimensional, computer image of each heart and track gradual deformations during each heartbeat.
"Making new use of magnetic resonance imaging technology, we have been able to gather the first visual clues of how heart disease develops regionally and possibly spreads to different parts of the heart and cardiovascular system," says
senior study investigator and cardiologist João Lima, M.D., associate professor of medicine and radiology at The Johns Hopkins University School of Medicine and its Heart Institute.
According to Lima, cardiologists are aware of many diseases that lead to deformations in the heart's shape, both big and small, but this is the first experiment to have traced or mapped these changes in great detail.
The results of the Hopkins-led study of adults 45 to 85 are among the first to emerge from the Multiethnic Study of Atherosclerosis, called MESA for short, which is monitoring nearly 7,000 men and women of different ethnic backgrounds and
with no existing signs of heart disease to determine who develops coronary artery disease and who does not. To minimize any bias in interpretation of results, some scans were analyzed twice and by any one of three cardiologists.
For every scan, calculations were made for more than a dozen parameters of heart function, including thickness of various heart walls, pumping volume, ejection fraction (the percentage of blood pumped from the left ventricle during a heart
beat), and shortening fraction (how much each muscle shortens during contraction), blood pressure (an indicator of the workload or stress on the heart), and body mass index.
To calculate total changes in heart shape, which is three-dimensional, the researchers relied on a previous model that used MRI scans to calculate a ratio of muscle mass to volume of pumped blood. The greater the ratio, the greater the
amount of concentric heart remodeling that has occurred.
When the researchers compared changes in heart shape to changes in heart function, statistical analysis showed that pumping function deteriorates as hearts increasingly change shape or remodel. Changes in heart shape often involved gains
in mass and wall thickening.
The results confirmed for both men and women that changes in one particular region of the heart, the anterior wall of the left ventricle, were linked to the greatest declines in heart function.
The Hopkins researchers also found that particular patterns of remodeling and related heart function differ between men and women. In men, increased remodeling and decreased heart function appear to be gradual and steady over time. In
women, initial results showed a temporary benefit to remodeling: Their heart function slightly improved during the heartbeat, before a steep decline in heart function ensued.
"Our results raise the possibility that early treatments for regional heart problems could eventually be used to prevent or suppress larger problems from developing, which could affect the entire cardiovascular system," says lead study
author and cardiologist Boaz Rosen, M.D., a senior research fellow at Hopkins. "We have also shown that it is now possible to map changes of the heart in an early stage of their development, increasing the diagnostic and predictive
applications of MRI as a key tool in combating cardiovascular disease."
The specific MRI technique used in this study was developed at Hopkins by radiologist Elias Zerhouni, M.D., and further improved by radiology engineer Nael Osman, Ph.D. Because of the large size of an MRI machine, taking pictures requires
that patients lie down on a platform that is moved within the magnets' coils.
Funding for this six-center trial, which will study patients for six to eight years, comes from the National Heart, Lung and Blood Institute, a member of the National Institutes of Health. |
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HOPKINS ABROAD |
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Hopkins Physicians Conduct Study in Sahara Desert
Brian Krabak, M.D., and Brandee Waite, M.D., sports medicine and rehabilitation specialists from the Johns Hopkins Department of Orthopedics will once more lead the medical team of a race across the desert.
Chosen in March of this year to lead the medical team at the Gobi Desert race organized by RacingThePlanet®, the physicians will now face a new challenge. They not only will lead an international team of volunteers and medical doctors, but
also use the opportunity to conduct a study on how highly demanded athletes behave during the race.
"We will measure from heart rate to perspiration and determine the limits of these elite athletes," says Dr. Krabak.
Again, as Dr. Waite says, one of the biggest challenges will be to make the tough decision of whether an injured athlete should compete and risk further injury; not a simple decision in the face of athletes' "burning desire to continue".
Part of the 4 Deserts™ race (Atacama in Chile, Gobi in China, Sahara in Egypt and Artarctica) the race now shifts to Egypt with a 250 kilometer race planned across the hottest place on Earth. The third leg of the 4 Deserts™ series, will
take place September 25th – October 1st in the great Sahara Desert of Egypt.
The race will feature 100 competitors from more than 20 nations around the world with equal numbers coming from Asia, North America and Europe. The Sahara Race is a seven-day competition, divided into six-stages. Beginning on the morning
of September 25th, competitors will have to make their way through multiple checkpoints until reaching five campsites established daily. Each stage is roughly a marathon (42 kilometers in length) but there is also one 80 kilometer stage
held over two days during which competitors race through the night guided by bright green glow sticks. Only a ration of water and a place in a tent is provided daily. Competitors must carry all their own food and gear for the duration of
the race which adds to the immense effort of making it to the finishing line.
The race will be in a pristine and little traveled area of the secluded Sahara Desert in Egypt. Competitors will follow a course from the Farafra Oasis to the Bahariya Oasis crossing the spectacular Black and White Deserts. In the White
Desert, often referred to as the "ghost town," natural chalk sculptures formed over thousands of years by wind erosion rise up out of the desert to provide spectacular scenery. The terrain throughout the race will vary from sand dunes to
dried river beds to rocky plateaus. Competitors will also be treated to several natural sulfur springs along the way before making their way back to Cairo to finish at the ancient Giza Pyramids.
The field will be exceptionally diverse with individuals ranging in age from 21-year-old Han Jang of Korea to 73-year-old Laurie Brophy of Wales in the United Kingdom. Also among the competitors will be Kyung Tae Song from Korea, who is
blind and will enter the race aided by his guide. Competitors represent many professions including investment banking, law, venture capital, medicine and academia, among others.
Johns Hopkins Medicine International will keep a journal at the
www.jhintl.net website, as well as in the Korean (
www.hopkinskorea.com) and Spanish (
www.saludhopkins.com) websites.
There's also the possibility of a video journal, as the Johns Hopkins Office of Telemedicine will make satellite transmission available from the different checkpoints of the race.
CME COURSES
October 15, 2005
CT Angiography: Principles, Techniques and Clinical Applications-MI
Detroit Marriott at the Renaissance Center
Detroit, MI
October 19, 2005
CME Grand Rounds/RSC Workshop
Johns Hopkins Broadway Research Building
Baltimore, MD
October 28, 2005
What's New in Diabetic Retinopathy and Venous Occlusive Disease
Johns Hopkins University School of Medicine, Turner Building
Baltimore, MD
October 29, 2005
11th Annual Update in Hematologic Malignancies
Johns Hopkins School of Medicine, Turner Auditorium
Baltimore, MD |
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