(Press-News.org) Tall, thin women face a greater risk of infection with nontuberculous mycobacteria (NTM), cousins of the organism that causes tuberculosis, according to researchers at National Jewish Health. Women with NTM infections also showed a weakened immune response associated with their fat cells, in a paper published in the Jan. 15, 2013, issue of The American Journal of Respiratory and Critical Care.
"Nontuberculous mycobacteria are widespread in the environment, yet only some people develop infections," said Edward Chan, MD, senior author and professor of medicine at National Jewish Health. "These findings help us identify who is at greater risk for the disease, and may point to more effective therapies down the road."
There are dozens of NTM species. Although the organisms can infect skin and other body parts, they most commonly infect the lungs. Lung infections are very difficult to treat, often requiring surgery and years of therapy with powerful intravenous antibiotics. NTM infections can be fatal. Evidence suggests that infections have been rising in recent decades.
NTM species are widespread in water and soil, yet only about five to six people per 100,000 develop NTM infections each year; the incidence is higher in individuals older than 50. An estimated 30,000 to 120,000 people in the US currently have NTM infections. Researchers at National Jewish Health, which sees more NTM infections than any other medical center in the world, tried to figure out why only some exposed patients develop these difficult infections.
Elderly women represent the vast majority of NTM patients, accounting for 85 percent of the patients seen at National Jewish Health during the study, and averaging about 64 years of age. The researchers chose to compare the NTM patients with control subjects at an osteoporosis clinic because these individuals were similar age, race, and gender as the NTM patients.
When compared to the women visiting the osteoporosis clinic, the NTM patients were on average almost two inches taller, had body mass indices almost two points lower and 5.7 pounds less fat on their bodies. The NTM patients also more frequently had concave chests, a condition known as pectus excavatum, and scoliosis, or curvature of the spine.
"Tall, thin women definitely appear to be more susceptible to NTM infections," said Dr. Chan. "They share some characteristics of people with Marfan syndrome. Since Marfan syndrome is caused by a mutation in the fibrillin-1 gene, we plan to look at that gene as a potential source of NTM susceptibility."
In addition to body type, NTM patients also differed in their immune response. Fat cells produce hormones, leptin and adiponectin, known to regulate both weight and immune function. Leptin production generally increases as people grow fatter. It also helps stimulate the immune system to fight infections. Adiponectin, an immunosuppressive hormone, generally decreases as people grow fatter. While these standard relationships held for the control subjects, they broke down for NTM patients with levels of these fat-derived hormones varying only minimally with body fat in NTM patients.
"In addition to body type, NTM patients also appeared to have some dysregulation of their immune response, which could increase their susceptibility to NTM infections," said co-author Michael Iseman, MD, professor of medicine at National Jewish Health.
INFORMATION:
National Jewish Health is known worldwide for treatment of patients with respiratory, cardiac, immune and related disorders, and for groundbreaking medical research. Founded in 1899 as a nonprofit hospital, National Jewish Health remains the only facility in the world dedicated exclusively to these disorders. U.S. News & World Report has ranked National Jewish the #1 respiratory hospital in the nation for 15 consecutive years.
END
Researchers at Syracuse University's Department of Biomedical and Chemical Engineering at L.C. Smith College of Engineering and Computer Science are studying the toxicity of commonly used nanoparticles, particles up to one million times smaller than a millimeter that could potentially penetrate and damage cell membranes.
In a recent article published along with cover art in the leading journal Langmuir entitled "Effects of nanoparticle charge and shape anisotropy on translocation through cell membranes," researchers Shikha Nangia, assistant professor of biomedical and ...
What cancerous conditions lead to what kinds of bacterial infections? If doctors knew, they could predict which patients would likely benefit from pre-treatment with certain kinds of antibiotics. A University of Colorado Cancer Center study published in this month's issue of the International Journal of Infectious Diseases shows the answer: E. coli and Klebsiella pneumoniae are especially prevalent in patients with lung and GI cancers, more so for Klebsiella if these patients have been treated previously with aminopenicillins.
"These are really dangerous infections. You ...
COLLEGE PARK, Md. – Filipinos have been an invisible minority in Annapolis, Maryland for more than a century. Now, researchers at the University of Maryland are using oral histories as a way to flesh out their life and times – documenting the incredible challenges they faced – and successes they celebrated.
After the Spanish-American War, the Philippines became a U.S. territory. Filipinos were brought to Annapolis – home of the Naval Academy – to serve as desk interns, fire fighters, construction laborers, messmen and stewards. In many cases, the Naval Academy replaced ...
VIDEO:
This is a NASA TRMM satellite flyby of Tropical Cyclone Peta in the South Indian Ocean. TRMM revealed that rain was falling at a rate of up to 94 mm...
Click here for more information.
Infrared data from NASA's Aqua satellite has shown that soon after a low pressure system in northwestern West Australia became Tropical Storm Peta, it made landfall and started to fall apart.
Early on Jan. 22, the Joint Typhoon Warning Center (JTWC) gave System 93S a high chance for ...
OAK RIDGE, Tenn., Jan. 23, 2013 -- Looking toward improved batteries for charging electric cars and storing energy from renewable but intermittent solar and wind, scientists at Oak Ridge National Laboratory have developed the first high-performance, nanostructured solid electrolyte for more energy-dense lithium ion batteries.
Today's lithium-ion batteries rely on a liquid electrolyte, the material that conducts ions between the negatively charged anode and positive cathode. But liquid electrolytes often entail safety issues because of their flammability, especially as ...
Tropical Storm Oswald's heavy rains have caused flooding in Queensland, Australia and NASA's TRMM satellite measured almost two feet of rain fell in certain areas.
Tropical cyclone Oswald's sustained winds have never been greater than 35 knots (~40.2 mph) but the storm's extreme rainfall has resulted in widespread flooding in Australia over northern Queensland. Many roads have been reported flooded resulting in some communities being cut off.
NASA's Tropical Rainfall Measuring Mission (TRMM) is a satellite that can measure rainfall from space. TRMM-based satellite precipitation ...
The longstanding ethical framework for protecting human volunteers in medical research needs to be replaced because it is outdated and can impede efforts to improve health care quality, assert leaders in bioethics, medicine, and health policy in two companion articles in a Hastings Center Report special report, "Ethical Oversight of Learning Health Care Systems." One of the authors calling for a new approach is the main architect of the current ethical framework.
Seven commentaries in the publication, written by leaders with national responsibility for ethical oversight ...
[EMBARGOED FOR JAN. 24, 2013] Pediatric rotavirus vaccination also indirectly protects unvaccinated adults from the highly contagious cause of severe diarrhea and vomiting, suggests a new study published in Clinical Infectious Diseases and available online. The findings suggest pediatric immunization against the virus may be more cost effective than previously thought, given rotavirus-related health care costs among adults.
Before the vaccine, rotavirus caused an estimated 24 million outpatient visits, 2.4 million hospitalizations, and 453,000 deaths in infants and young ...
A Phase 3 clinical trial demonstrates that tofacitinib improves disease activity and inhibits progression of joint damage in rheumatoid arthritis (RA) patients who did not respond to methotrexate (MTX). Results of the 12-month interim analysis of the efficacy of tofacitinib appear in Arthritis & Rheumatism, a journal published by Wiley on behalf of the American College of Rheumatology (ACR).
RA is a chronic, autoimmune disease that causes inflammation, pain and swelling of the joints. Over time, RA may destroy joints, impair daily function, and lead to significant disability. ...
The first ever review of abuse cases related to child death or serious injury in Northern Ireland will be launched at Queen's University today (24 January 2013). The review, Translating Learning into Action, was commissioned by the Department of Health, Social Services and Public Safety (DHSSPS) and was carried out by researchers at Queen's University and the NSPCC.
The Case Management Review (CMR) report – the first to be produced in Northern Ireland - analysed 24 case reviews relating to 45 children which resulted in death or serious injury in the period between 2003 ...
