Week of June 10, 2011
This week we look at bacteria resistant to antibiotics and how you can protect yourself, AIDS at 30 years, changing brain cells into heart cells and why athletes may need more Vitamin D.
WHO has identified antimicrobial resistance to antibiotics as one of the three greatest threats to human health.
The bacteria in your intestines are your immune system's first line of defense. Antibiotics affect not only the bacteria we wish to eliminate, but destroy the beneficial flora, which maintain the internal balance of bacterial growth. A bacterium such as Staphylococcus is normally maintained in balance, but can overgrow and become pathological under antibiotic treatment. When we take antibiotics much of the ecosystem of the bacteria is disrupted, so there can be overgrowth of bacteria which can lead to disease. A healthy intestinal bacterial flora prevents foreign bacteria from entering your bloodstream through the gut.
While the development of specific antibiotics for pathological agents profoundly improved success in treating infectious disease, a hidden cost has emerged. The overuse of antibiotics to treat common ailments has led to a disruption of the internal microbiological ecosystems in our bodies.
The problems with the overuse of antibiotics are much the same as problems with pesticides and fungicides. When we destroy the natural balance of bacteria in the soil, the natural defenses against pests are compromised. When we eliminate all other plants (or weeds) to grow just one species, that species is more susceptible to disease.
Think of a field or a meadow. In its natural state many plants coexist in the natural development of an ecosystem. When man decides to remove certain unsightly plants that are seen as weeds, suddenly greater and greater energy is required to maintain this new unintegrated system. Look at our lawns, how much pesticides, weed killers, water and fertilizer are required. Biological systems thrive on diversity.
The weaker the system becomes the more resistant bacteria can overgrow and require more use of antibiotics. This is called antimicrobial resistance.
The World Health Organization has identified antimicrobial resistance to antibiotics as one of the three greatest threats to human health. Antimicrobial resistance is the outgrowth of overuse and misuse of antibiotics in human health and in animals, among other practices.
According to the Infectious Diseases Society of America, methicillin-resistant Staphylococcus aureus, or MRSA, which is the result of a staph infection that becomes resistant to antibiotics, kills more Americans every year than emphysema, HIV/AIDS, Parkinson's disease and homicides combined. Tuberculosis, which kills 2 million people worldwide every year, more than any other infectious disease, is becoming increasingly resistant to antibiotics.
The issue is of such growing concern that the World Health Organization dedicated World Health Day, April 7, to the topic, calling for increased attention to antibiotic-resistant bacteria worldwide.
The financial costs are great as well, according to the Infectious Diseases Society of America. Two common hospital-acquired infections, pneumonia and sepsis, which are generally the result of antibacterial-resistant pathogens, killed 50,000 Americans and cost the U.S. health care system $8 billion in 2006. The total cost to the health care system of antibiotic-resistant infections is thought to be $21 billion to $34 billion each year.
How do we counteract these negative effects of antibiotics? One method is to increase our consumption of healthy bacteria or probiotics. The World Health Organization defines probiotics as "live microorganisms, which when administered in adequate amounts confer a health benefit on the host." The most common types of these beneficial bacteria are Lactobacilli and Bifidobacteria. These are found in fermented foods such as yogurt and sauerkraut. Probiotics are also sold as dietary supplements in therapeutic doses. Previous studies indicate that probiotics may have a role in treating gastrointestinal illnesses, boosting immunity, and preventing or slowing the development of certain types of cancer.
Tucker, C. New Measures, Legislation Aimed at Antibiotic Resistance. Nations Health. 2011;41(5):1-2. American Public Health Association.
Lange, Andrew. Getting at the Root Treating the Deepest Source of Disease. North Atlantic Books.
Iyer C, Kosters A, Sethi G, et al. Probiotic Lactobacillus reuteri promotes TNF-induced apoptosis in human myeloid leukemia-derived cells by modulation of NF-kB and MAPK signaling. Cellular Microbiology. 2008;10(7):1442-1452.
Zhang W, Azevedo MSP, Wen K, et al. Probiotic Lactobacillus acidophilus enhances the immunogenicity of an oral rotavirus vaccine in gnotobiotic pigs. Vaccine. 2008;26(29-30):3655-3661.
AIDS at 30 years
On June 5, 1981, Morbidity & Mortality Weekly Report published a report of Pneumocystis carinii pneumonia in five previously healthy young men in Los Angeles, California; two had died. This report later was acknowledged as the first published scientific account of what would become known as human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS). Thirty years after that first report, the most recent estimate is that 33.3 million persons were living with HIV infection worldwide at the end of 2009.
In the United States, the CDC estimates that 1,178,350 persons were living with HIV at the end of 2008, with 594,496 having died from AIDS since 1981. At this 30-year mark, efforts are being accelerated under the National HIV/AIDS Strategy of the United States, with goals of reducing the number of persons who become infected with HIV, increasing access to care and optimizing health outcomes for persons living with HIV, and reducing HIV-related health disparities.
1. CDC. Pneumocystis pneumonia--Los Angeles. MMWR 1981;30:250-2.
2. Joint United Nations Programme on HIV/AIDS. Global report: UNAIDS report on the global AIDS epidemic 2010. Geneva, Switzerland: UNAIDS; 2010. Available at http://www.unaids.org/globalreport/global_report.htm. Accessed May 26, 2011.
3. CDC. HIV surveillance--United States, 1981-2008. MMWR 2011;60:689-93.
4. CDC. Diagnoses of HIV infection and AIDS in the United States and dependent areas, 2009. HIV surveillance report, vol. 21. Atlanta, GA: US Department of Health and Human Services, CDC; 2010. Available at http://www.cdc.gov/hiv/surveillance/resources/reports/2009report/index.htm. Accessed May 26, 2011.
5. Office of National AIDS Policy. National HIV/AIDS strategy. Washington, DC: Office of National AIDS Policy; 2010. Available at http://www.whitehouse.gov/administration/eop/onap/nhas. Accessed May 26, 2011.
Researchers Reprogram Brain Cells to Become Heart Cells
The Chinese character for the mind is also the same character for the heart. The association with the heart as the center for feelings has remained in our language for human emotion.
For the past decade, researchers have tried to reprogram the identity of all kinds of cell types. Heart cells are one of the most sought-after cells in regenerative medicine because researchers anticipate that they may help to repair injured hearts by replacing lost tissue. Now, researchers at the Perelman School of Medicine at the University of Pennsylvania are the first to demonstrate the direct conversion of a non-heart cell type into a heart cell by RNA transfer.
Working on the idea that the signature of a cell is defined by molecules called messenger RNAs (mRNAs), which contain the chemical blueprint for how to make a protein, the investigators changed two different cell types, an astrocyte (a star-shaped brain cell) and a fibroblast (a skin cell), into a heart cell -- using mRNAs.
James Eberwine, Ph.D., the Elmer Holmes Bobst Professor of Pharmacology, Tae Kyung Kim, Ph.D., post-doctoral fellow, and colleagues report their findings online in the Proceedings of the National Academy of Sciences. This approach offers the possibility for cell-based therapy for cardiovascular diseases.
University of Pennsylvania School of Medicine (2011, July 9). A Change of Heart: Researchers reprogram brain cells to become heart cells. ScienceDaily. Retrieved July 11, 2011, from http://www.sciencedaily.com/releases/2011/07/110708160346.htm
T. K. Kim, J.-Y. Sul, N. B. Peternko, J. H. Lee, M. Lee, V. V. Patel, J. Kim, J. H. Eberwine. Transcriptome transfer provides a model for understanding the phenotype of cardiomyocytes. Proceedings of the National Academy of Sciences, 2011; DOI: 10.1073/pnas.1101223108
Vitamin D Lower in NFL Football Players Who Suffered Muscled Injuries.
ScienceDaily (July 10, 2011) -- Vitamin D deficiency has been known to cause an assortment of health problems. Now, a recent study -- being presented at the American Orthopaedic Society for Sports Medicine's (AOSSM) Annual Meeting in San Diego -- suggests that lack of the vitamin might also increase the chance of muscle injuries in athletes, specifically NFL football players.
"Eighty percent of the football team we studied had vitamin D insufficiency. African American players and players who suffered muscle injuries had significantly lower levels," said Michael Shindle, MD, lead researcher and member of Summit Medical Group.
American Orthopaedic Society for Sports Medicine (2011, July 10). Vitamin D lower in NFL football players who suffer muscled injuries, study suggests. ScienceDaily. Retrieved July 11, 2011, from http://www.sciencedaily.com/releases/2011/07/110710132807.htm