Archive for January, 2011

HEPA FILTERS REDUCE CARDIOVASCULAR HEALTH RISKS ASSOCIATED WITH AIR POLLUTION

Friday, January 21st, 2011

Burnaby, British Columbia
Using inexpensive air filters may help reduce cardiovascular disease risk that results from exposure to air pollution, according to researchers from Canada, who studied healthy adultsliving in a small community in British Columbia where wood burning stoves are the main sources of pollution. The researchers found that high efficiency particle air (HEPA)filters reduced the amount of airborne particulate matter, resulting in improved blood vessel health and reductions in blood markers that are associated with an increased risk of cardiovascular disease.

Ryan Allen MS, PhD
Ryan Allen MS, PhD
Assistant Professor,
Health Sciences,
Simon Fraser University,
Burnaby, BC, Canada
Photo: soeh.ubc.ca

The findings were published online ahead of the print edition of the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.

“Our main objectives were to evaluate the potential for a simple intervention to improve indoor air quality and reduce pollution-related cardiovascular health risks and to better understand the mechanisms that contribute to air pollution related cardiovascular health problems” said Ryan Allen, PhD, assistant professor, Simon Fraser University, Burnaby, British Columbia. “Specifically, we were interested in learning more about the effects of residential wood smoke on the endothelium, the cells that line the inside of blood vessels, and on systemic inflammation, which is related to cardiovascular disease risk.”

Previous studies on the effects of air pollution on cardiovascular disease have been conducted primarily in urban areas and have focused largely on vehicle emissions,Dr. Allen noted. The results of those studies have indicatedpollution causes inflammation in the lungs and vessels and may also cause endothelial cells to function poorly, ultimately contributing to cardiovascular disease; however, few studies have been conducted in smaller communities or communities where woodsmoke is a main source of pollution, he added.

The researchers recruited 45 adults from 25 homes. Individuals from self reported tobacco smoking households were excluded from participating. Each participant’s home was monitored for two consecutive seven-day periods, during which time a HEPA filter (Honeywell model 50300) was operated in the main activity room and a quieter HEPA filter (Honeywell 18150) was operated in the participant’s bedroom. HEPA filters were operated normally during one seven-day period and without the internal filters in place during the other period. The order of filtration or non-filtration was random and participants did not know during which period the air was being filtered. Indoor pollution sampling equipment was placed in each home’s main activity room.Participants were asked to record their activities, locations and proximity to pollution sources every 60 minutes.Of the 25 homes enrolled in the study, 13 had woodstoves in use during the study period.

At the end of each 7 day period blood and urine samples were collected from each participant and markers of cellular injury, as well as the body’s response to that injury, were measured. Endothelial function also was evaluated using a fingertip device to evaluate blood volume in small blood vessels, and air samples were collected and analyzed.

Specifically, the researchers measured reactive hyperemia, a transient increase in blood flow which follows a period of ischemia, or blood flow shortage.A reduced reactive hyperemia index indicates blood vessels have an impaired response to changes in blood flow, and is an indicator of the earliest stages of atherosclerosis. Levels of a blood protein called C-reactive protein, which increase during inflammation, were also measured.

After analyzing their data, the researchers found portable HEPA filters reduced the average concentrations of fine particulates inside homes by 60% and woodsmoke by 75%, and their use was associated with improved endothelial function (a 9.4% increase in reactive hyperemia index) and decreased inflammation (a 32.6% decrease in C-reactive protein).

“Our results support the hypothesis that systemic inflammation and impaired endothelial function, both predictors of cardiovascular morbidity, can be favorably influenced by a reduction of particle concentration and add to a growing body of evidence linking short term exposure to particulate matter with a systemic inflammatory response,” Dr. Allen said.”Reducing air pollution appears to provide health benefits even if the pollution levels are already relatively low.”

HEPA filters offer an accessible option to help reduce the risks of cardiovascular disease that may be associated with inhaling wood smoke, especially as consumers turn more frequently to woodstoves as a source of heat, he added.

“HEPA filters are a potentially useful intervention since they are relatively inexpensive to purchase and operate and can effectively remove tiny particles that can be inhaled, to improve air quality inside homes where the majority of time is spent,” Dr. Allen noted. “The importance of residential wood smoke as a source of air pollution is likely to increase due to the rising costs of other fuels.”

Dr. Allen said future studies may help determine the health benefits of programs that promote the replacement of older, highly-polluting woodstoves with cleaner burning alternatives.

“Ultimately, the best safeguard against these health risks is to minimize the amount of air pollution that is created,” he said.

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ENGINEERING TEAM INVENTS “LAB ON A CHIP” FOR FAST, INEXPENSIVE BLOOD TESTS

Monday, January 10th, 2011

KINGSTON, R.I
While most blood tests require shipping a vial of blood to a laboratory for analysis and waiting several days for the results, a new device invented by a team of engineers and students at the University of Rhode Island uses just a pinprick of blood in a portable device that provides results in less than 30 minutes.

Mohammad Faghri, URI professor
Mohammad Faghri
URI professor of
mechanical engineering
Photo: mcise.uri.edu

“This development is a big step in point of care diagnostics, where testing can be performed in a clinic, in a doctor’s office, or right at home,” said Mohammad Faghri, URI professor of mechanical engineering and the lead researcher on the project. “No longer will patients have to wait anxiously for several days for their test results. They can have their blood tested when they walk into the doctor’s office and the results will be ready before they leave.”

With the new lab on a chip technology, a drop of blood is placed on a plastic polymer cartridge smaller than a credit card and inserted into a shoebox sized biosensor containing a miniature spectrometer and piezoelectric micro pump. The blood travels through the cartridge in tiny channels 500 microns wide to a detection site where it reacts with preloaded reagents enabling the sensor to detect certain biomarkers of disease.

Several patents are pending on the invention.

Compared to similar devices in development elsewhere, the URI system is much smaller, more portable, requires a smaller blood sample, and is less expensive. While the sensor costs about $3,200, each test costs just $1.50, which is the cost for the plastic cartridge and reagents.

The first cartridges the researchers developed focus on the detection of C-reactive proteins (CRP) in the blood, a preferred method for helping doctors assess the risk of cardiovascular and peripheral vascular diseases. From 2002 to 2004 (the only years for which data are available), the number of CRP tests paid for by Medicare tripled from 145,000 to 454,000, and it is estimated that those numbers have quadrupled since then.

Faghri said that additional cartridges can be designed to detect biomarkers of other diseases. The researchers are already working to engineer the device to detect levels of the beta amyloid protein that can be used as a predictor of Alzheimer’s disease. The device can also be engineered to detect virulent pathogens, including HIV, hepatitis B and H1N1 (swine) flu.

The next generation of the device will incorporate a hand-held sensor that will reduce manufacturing costs. Faghri also envisions a further miniaturization of the invention that can be adapted as a smartphone application. By embedding the biosensor in the cartridge and using the computer power of the phone, as well as its wireless communication capabilities, Faghri believes that patients may be able to conduct the tests themselves and have the results transmitted immediately to their doctor’s office via their phone. Among many other benefits, this should help to significantly reduce health care costs.

“We are already making progress on many of the steps toward the next generation of the system, and it won’t be long before we can begin to commercialize it,” Faghri said.

>>>>>Read all the latest in our HeartVigor.com News Page.

A NEW DRUG TARGET IN ATHEROSCLEROSIS: THE ANAPHYLATOXIN C5a

Tuesday, January 4th, 2011

For decades, doctors have looked at fitness levels, weight, and overall health risk factors for heart disease and stroke. Now, they may soon add a new risk factor to the list: activation of the complement system. The complement system is usually implicated in immune responses, but now there’s a role for it in cardiovascular disease. In a new research report appearing in the January 2011 print issue of the FASEB Journal (http://www.fasebj.org), scientists from Europe and the United States show that anaphylatoxin C5a, a protein released when complement is activated, contributes to atherosclerotic disease. C5a causes plaques to break free from where they would be anchored to ultimately cause blockages elsewhere in the body. This new discovery not only shows that C5a is a new marker for identifying risk for heart attack and stroke, but it also establishes C5a as a new therapeutic target for preventing these problems.

Johann Wojta, Ph.D.
Johann Wojta, Ph.D.
Photo: meduniwien.ac

“Given the huge impact of cardiovascular disease in general, and atherosclerosis in particular, on public health, we feel that unraveling mechanisms involved in the development and progression of the disease are of utmost importance,” said Johann Wojta, Ph.D., a researcher involved in the work from the University of Vienna in Austria. “Our findings have identified a particular component possibly involved in the development of atherosclerosis as a target for future therapies.”

To make this discovery, Wojta and colleagues treated white blood cells with the C5a. In turn, these cells responded with the production of specific enzymes capable of dissolving the inner wall of atherosclerotic plaques in coronary or brain vessels. This causes the plaques to rupture, break free from where they are anchored, and ultimately create a blockage of the vessels, leading to the development of more serious problems such as heart attacks or strokes. The researchers also showed that C5a was present in blood vessels of patients with myocardial infarction, but not in cardiac patients without infarct. This suggests that inhibiting C5a might provide a therapeutic tool in the prevention or treatment of atherosclerosis, as well as other diseases with immune system participation such as arthritis.

“Up to now, anaphylatoxin C5a has been mainly implicated in immunologic diseases such as asthma, rheumatoid arthritis or lupus,” said Gerald Weissmann, M.D., Editor in Chief of the FASEB Journal. “But now, this study shows that C5a, a product of an activated complement system may be responsible for the devastating effects of atherosclerosis.”

>>>>>Read all the latest in our HeartVigor.com News Page.

CALL FOR TRUTH IN TRANS FATS LABELING BY THE FDA

Monday, January 3rd, 2011

Case Western Reserve study shows how deceptive food labels lead to increased risk of deadly diseases.

Eric Brand
Eric Brand
Photo: inkedin.com

Did you know that when you pick up a product promoted as trans fat free, you may still be ingesting a significant amount of this potentially harmful substance? An article by Case Western Reserve University School of Medicine student Eric Brandt, published in the January/February 2011 issue of the American Journal of Health Promotion, reveals that misleading labeling practices can result in medically significant intake of harmful trans fat, despite what you read on Food and Drug Administration (FDA) approved labels. Indeed, consumers’ inability to identify high-risk foods may cause individuals to exceed the daily recommended value of 1.11 grams of trans fat from processed foods and lead to adverse long-term health side effects.

Ingestion of trans fat is a known public health concern. Top national health organizations, such as the U.S. Department of Health and Human Services and American Heart Association, suggest trans fats be ingested in limited quantities. However, current FDA labeling protocol and policy prevents the public from accessing the true amount of trans fat contained in their food products.

Current law requires that fat content of greater than five grams be listed in one gram increments, less than five grams be listed in .5 gram increments, and lower than .5 grams as containing zero grams of fat. Meaning, if a product has .49 grams of trans fat, the label can list the trans fat content as zero, thus masking a significant amount of trans fat that can exceed recommended limits and potentially lead to various adverse health effects.

Trans fat consumption has been linked to increased risk of coronary artery disease, diabetes, and sudden cardiac death. Because the daily recommended amount of trans fat from processed foods is only 1.11 grams, one would only need to consume a few deceptively labeled trans fat foods to exceed the healthy recommended intake. As few as three deceptively labeled trans fat items would exceed the healthy recommended intake; for example, consuming three serving sizes each with .49 grams of trans fat, totaling 1.47 grams. Despite what seems to be a small amount of trans fat to ingest, research shows that increasing daily trans fat consumption from .9% to 2.1%, or from two grams to 4.67 grams, will increase one’s risk of cardiovascular disease by 30%.

In an effort to adhere to its mission and responsibility in “helping the public get the accurate, science-based information they need to use medicines and foods to maintain and improve their health,” Brandt recommends the FDA revise its labeling protocol in order to prevent misleading the public about the amount of trans fat they are consuming. He recommends the FDA require food labels to report trans fat content in smaller increments, enabling consumers to recognize significant levels of trans fat in food products and allow one to properly manage their consumption. The suggested change will increase awareness of accurate food trans fat content, empower informed food choices, and improve public health outcomes.

>>>>>Read all the latest in our HeartVigor.com News Page.