Progression of Alzheimer's disease linked to the heart
Alzheimer's disease (AD) may progress more rapidly in people with high blood pressure or a form of irregular heartbeat, atrial fibrillation, according to results of a Johns Hopkins study published in the Nov. 6, 2007, issue of Neurology. The findings suggest that treating these conditions may also slow memory loss in people with AD.
The study examined 135 men and women over 65 who were newly diagnosed with AD. All had undergone annual memory tests for an average of three years.Results showed that 10 with high blood pressure (systolic pressure over 160) at the time of AD diagnosis showed a rate of memory loss roughly 100 percent faster than those with normal blood pressure. In addition, 10 with atrial fibrillation at the time of the diagnosis showed a rate of memory decline that was 75 percent faster than those with normal heartbeats.
Defibrillators save lives
Findings from experts at Johns Hopkins as well as elsewhere support the widespread placement of automated external defibrillators, the paddle-fitted, electrical devices used to shock and revive people whose hearts have suddenly stopped beating. The team's study results were presented on November 5, 2007, at the American Heart Association's annual Scientific Sessions in Orlando and were among the first conclusions to emerge from a landmark series of studies,known as the Resuscitation Outcomes Consortium, designed to reveal thebest life-saving techniques for cardiac emergencies.
Every year, experts say, more than 300,000 Americans of all ages die from sudden cardiac death. A good many of them are seniors. In the latest work, researchers found - in real-life, emergencysituations - that use of the laptop-size devices by random bystanders more than doubled survival rates among victims felled by a sudden heart stoppage due to a heart attack or errant heart rhythm. Each device, which costs, on average, more than $2,000, is equipped with a digital instruction screen that provides simple, step-by-step directions.
[It might be noted that the Northpark Mall in Joplin provides two AED defibrillators, one is located on a pillar between Yankee Candle and the former Victoria's Secret location near the Food Court; the other is located between Select Comfort and B. Dalton. According to Lori Jones, marketing director, the mall staff has been trained fully in their use.]
Effects of the aging heart
Researchers at Johns Hopkins have evidence to explain why the supposedly natural act of aging is by itself a very potent risk factor for life threatening heart failure. In a study presented November 4, 2007, at the American Heart Association's (AHA) annual Scientific Sessions in Orlando, the Hopkins teamanalyzed more than a half dozen measurements of heart structure and pumping function to assess minute changes in the hearts of 5,004 men and women, age 45 to 84, of different ethnic backgrounds and with noexisting symptoms of heart disease.
Researchers found that each year as people age, the time it takes for their heart muscles to squeeze and relax grows longer, by 2 percent to 5 percent.
Health insurance for Mexicans
The results of a study by the Johns Hopkins University Bloomberg School of Public Health conclude that Seguro Popular, Mexico's new health insurance program intended to reach the nation's 50 million uninsured by 2010, is having a positive effect on coverage of antihypertensive treatment in the country. The study was published in the October 27, 2007 issue of the British Medical Journal.
"Lack of health insurance has been consistently identified as a key obstacle to hypertension treatment and Mexico is among the last of the Organization for Economic Co-operation and Development countries to guarantee health insurance for all of its citizens," said Sara N. Bleich, PhD, lead author of the study.
Broccoli, eat it or spread it
A team of Johns Hopkins scientists reports in the October 22, 2007 issue of the Proceedings of the National Academy of Sciences that humans can be protected against the damaging effects of ultraviolet (UV) radiation--the most abundant cancer-causing agent in our environment --by topical application of an extract of broccoli sprouts.
The results in human volunteers, backed by parallel evidence obtained in mice, show that the degree of skin redness (erythema) caused by UV rays, which is an accurate index of the inflammation and cell damage caused by UV radiation, is markedly reduced in extract-treated skin.
Importantly, notes investigator Paul Talalay, M.D., professor of pharmacology, this chemical extract is not simply a sunscreen. Unlike sunscreens, it does not absorb UV light and prevent its entry into the skin. Rather, the extract works inside cells by boosting the production of a network of protective enzymes that defend cells against many aspects of UV damage. Consequently, the effects are long-lasting; the protection lasts for several days, even after the extract is no longer present on or in the skin.
As skin cancer incidence is rising dramatically due to the escalating exposure of aging populations to the UV rays of the sun, Talalay says that "treatment with this broccoli sprout extract might be another protective measure that alleviates the skin damage caused by UV radiation and thereby decreases our long-term risk of developing cancer."
The protective chemical agent in the broccoli sprout extracts is sulforaphane. It was first identified by Talalay and his colleagues more than 15 years ago and has been shown to prevent tumor development in a number of animals treated with cancer-causing chemicals.
Bum heart? Better to be insured
Emergency departments across the nation are failing to meet national goals in treating many heart attack and pneumonia patients, according to a study by Johns Hopkins researchers published in the October 2007 issue of Academic Emergency Medicine.
The investigators studied records of 1,492 heart attack patients and 3,955 pneumonia patients seen at 544 emergency departments between 1998 and 2004 and found that care levels were dependent on race, geography and type of health insurance. Results showed only 40 percent ED compliance with recommended aspirin therapy and 17 percent with recommended beta blocker treatment of heart attack patients.
Only 69 percent of patients with pneumonia got recommended antibiotics, and fewer than half (46 percent) had blood oxygen levels assessed as recommended by the American Thoracic Society. The Joint Commission regulating hospitals and the Centers for Medicare and Medicaid Services say all eligible heart attack and pneumonia patients presenting to EDs should receive aspirin/beta blocker therapy, or antibiotic and oxygen assessment, respectively.
"If these numbers are applied nationwide, we estimate that as many as 22,000 deaths a year could be prevented in the U.S. if ED caregivers followed practice standards," said Julius Pham, M.D., principal investigator for the study and assistant professor of medicine in the Johns Hopkins departments of Emergency Medicine and Anesthesiology and Critical Care Medicine. "More resources should be directed at studying why this is happening and developing strategies to ensure that 100 percent of patients get the recommended treatments."
Why one E. coli bacterium becomes two...and so on
In process that is shrouded in mystery, rod-shaped bacteria reproduce by splitting themselves in two. By applying advanced mathematics to
laboratory data, a team led by Johns Hopkins researchers has solved a small but important part of this reproductive puzzle. Their bacteria research was reported in the October 9, 2007 edition of Proceedings of the National Academy of Sciences.
The findings apply to highly common rod-shaped bacteria such as E. coli, found in the human digestive tract. When these single-celled
microbes set out to multiply, a signal from an unknown source causes a little-understood structure called a Z-ring to tighten like a rubber band around each bacterium's midsection. The Z-ring pinches the rod-like body into two microbial sausages that finally split apart. To shed light on this process, the Johns Hopkins-led team developed a mathematical tool that computed the mechanical force exerted by the Z-ring when it helps these cells split.
The calculation will aid scientists who are trying to learn more about how these microbes live and reproduce. The work also may hasten the development of a new type of antibiotic that could disable the Z-ring to keep harmful bacteria in check.
Attacking colorectal cancer
Johns Hopkins scientists have developed a potentially novel way to fight colorectal cancer using tiny molecules to deliver potent barrages of radiation inside cancer cells, unlike current treatments that bind to the surface of cells and attack from the outside and cause unwanted side effects.
In laboratory studies with normal and cancer cells, the new radiation delivery system proved able to specifically target colon cancer cells, and what's left over is likely to be easily filtered out by the kidneys because the delivery system's molecules are so small.
As reported online in PLoS One on October 3, 2007, Johns Hopkins colorectal cancer specialists John Abraham, Ph.D., and Stephen Meltzer, M.D. -- working with the notion that small molecules generally make better treatment packages -- designed small bits of protein only 10 amino acids long as the foundation for their drugs. By contrast, antibodies used to deliver radiation or chemicals can be over 1,000 amino acids long.
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