The same mechanism that helps you detect bad-tasting and potentially poisonous foods may also play a role in protecting your airway from harmful substances, according to a study by scientists at the University of Iowa Roy J. and Lucille A. Carver College of Medicine. The findings could help explain why injured lungs are susceptible to further damage.  

The study, published online July 23 in Science Express, shows that receptors for bitter compounds that are found in taste buds on the tongue also are found in hair-like protrusions on airway cells. In addition, the scientists showed that, unlike taste cells on the tongue, these airway cells do not need help from the nervous system to translate detection of bitter taste into an action that expels the harmful substance. 

The hair-like protrusions, called motile cilia, were already known to beat in a wave-like motion to sweep away mucus, bacteria and other foreign particles from the lungs. 

The study is the first to show that motile cilia on airway cells not only have this “clearing” function, but also use the receptors to play a sensory role. The researchers also found that when the receptors detect bitter compounds, the cilia beat faster, suggesting that the sensing and the motion capabilities of these cellular structures are linked. 

“On the tongue, bitter substances trigger taste cells to stimulate neurons, which then evoke a response — the perception of a bitter taste. In contrast, the airway cells appear to use a different mechanism that does not require nerves,” said Alok Shah, a UI graduate student and co-first author of the study. “In the airways, bitter substances both activate the receptors and elicit a response — the increased beating of the cilia — designed to eliminate the offending material.”

Shah and co-first author Yehuda Ben-Shahar, Ph.D., an assistant professor of biology at Washington University who was a postdoctoral fellow at the UI when the study was conducted, worked in the lab of senior study author Michael Welsh, M.D. (photo, upper left), UI professor of internal medicine and molecular physiology and biophysics, who holds the Roy J. Carver Chair of Internal Medicine and Physiology and Biophysics. Welsh also is a Howard Hughes Medical Institute investigator. 

“These findings suggest that we have evolved sophisticated mechanisms to guard ourselves from harmful environmental stimuli,” Ben-Shahar said. “Our work also suggests that losing cilia in the lungs, due to smoking or disease, would result in a reduced general ability to detect harmful inhaled chemicals, increasing the likelihood of further damaging an injured lung.”

In addition to Ben-Shahar, Shah and Welsh, the UI team included Thomas Moninger, assistant director of the UI Central Microscopy Research Facility, and Joel Kline, M.D., UI professor of internal medicine. 

The study was funded by grants from the National Institutes of Health. 

Reference:   University of Iowa, Airway cells use ‘tasting’ mechanism to detect and clear harmful substances, July 24, 2009

A recent paper on sauna therapy by Dr. Martin L. Pall argues for a novel mechanism for its mode of action (1). Pall argues that sauna therapy acts primarily by increasing the availability of a compound called tetrahydrobiopterin (BH4) in the body. BH4 is reported or thought to be depleted in a number of medical conditions that are also reported to respond positively to sauna therapy, including multiple chemical sensitivity, fibromyalgia, chronic fatigue syndrome, hypertension, vascular endothelial dysfunction and heart failure. This pattern of action can be explained, therefore, if sauna therapy increases the availability in the body of BH4.

Pall argues for two distinct mechanisms by which sauna therapy is expected to increase availability of BH4. Both of these act by increasing the synthesis of an enzyme, known as GTP cyclohydolase I, the rate limiting enzyme in the biosynthesis of BH4.

Sauna therapy is known to produce large increases in blood flow in the outer heated parts of the body and the consequent increase in vascular shear stress has been shown to induce large increases in GTP cyclohydrolase I activity and consequent increases in BH4.

A second such mechanism is mediated through the action of the heat shock protein, Hsp90, a protein known to be induced by modest tissue heating and a protein that is recruited into a complex of proteins containing GTP cyclohydrolase I. The Hsp90 protein lowers the proteolytic degradation of GTP cyclohydrolase I protein, leading to increased BH4 synthesis and this has been shown to lower, in turn, the partial uncoupling of the eNOS nitric oxide synthase. Increases in BH4 synthesis in response to both of these two mechanisms may be expected to feed BH4 to various tissues in the body including those not directly impacted by sauna therapy.

The health benefits of vigorous exercise may also be mediated, in part, via these same mechanisms.

A number of additional diseases are reported to involved BH4 depletion including Alzheimer’s, Parkinson’s, asthma, schizophrenia, bipolar disorder, pulmonary hypertension and type 2 diabetes so that each of these may respond to sauna therapy, as well.

It has been commonly assumed that the response of MCS cases to sauna therapy is mediated by a detoxification process known as depuration. There is some published evidence that some increase in detoxification does occur in response to sauna therapy. However the main influence of sauna therapy on MCS cases and certainly in these other medical conditions may well be through increased BH4 availability.

Reference: 1. Pall ML. 2009 Do sauna therapy and exercise act by raising the availability of tetrahydrobiopterin? Med Hypotheses. 2009 Jul 4.

The Federal Institute for Occupational Safety and Occupational Medicine has published an alphabetical and systematic Thesaurus “Safety and Health at Work”. The Thesaurus has been created in a long-standing cooperation between documentalists, librarians and scientists from the Federal Institute of Occupational Safety and Occupational Medicine.    

The disease MCS – Multiple Chemical Sensitivity (ICD-10 T78.4) is mentioned at the Thesaurus “Safety and Health at Work”, alphabetical Part, Status May 2009, as: 

Multiple Chemical Sensitivity (B02.19.00)     

At the systematic Part MCS – Multiple Chemical Sensitivity is found at the category B02:  

“Work related Disease and Occupational Disease/Disease”  

integrated in Part:  

• B02.19 Other Disease 
• B02.19.00 Multiple Chemical Sensitivity  

Chronic Fatigue Syndrome (CFS) is integrated analogue.  

MCS is not classified as a mental disease

To clear up occurring doubts, it is to point out that MCS – Multiple Chemical Sensitivity is not integrated into chapter B02.15: Mental diseases, Depression, Neurosis, Post traumatic Stress Disorder or psychosomatic diseases. 

Thesaurus “Safety and Health at Work”

The Thesaurus offers a quick overview on the broad group of themes “Safety and Health at Work”. It contains about 3 500 main keywords and is the joining of the keywords from the two previous Thesauri “Safety at Work” and “Occupational Medicine”. The Thesaurus is based on the practical work of the Library group, documentation at the content development and their research of technical literature. It is a tool for documentation.   

The Thesaurus is intended for all who search for literature about “Safety and Health at Work”. It is supportive for prearrangement of research inquiries at the data pool LITDOK and can be helpful for searching in topic related databases.  

Author: Silvia K. Müller, CSN – Chemical Sensitivity Network, July 23, 2009  

Reference:  Thesaurus „Sicherheit und Gesundheit bei der Arbeit“ Alphabetischer Teil, Systemischer Teil, Dortmund/Berlin/Dresden 2009. 

International Journal of Occupational and Environmental Health Features Discovery of Asbestos-Related Pain Origin from Scientists at the Karmanos Cancer Institute in Detroit 

Scientists at the Barbara Ann Karmanos Cancer Institute’s National Center for Vermiculite and Asbestos-Related Cancers (NCVAC) have discovered a probable reason for the unrelenting chest pain experienced in certain patients with asbestos-related diseases and cancers. The findings, featured in the July 20, 2009 edition of the International Journal of Occupational and Environmental Health, were published in an academic peer-reviewed manuscript by principal author Michael Harbut, M.D., MPH, co-director of the NCVAC and chief of the Center for Occupational and Environmental Medicine, affiliated with Wayne State University.  

Harbut reported the findings after studying a patient who was exposed to taconite dust as a child.  

Using a new radiography approach developed by Carmen Endress, M.D., FACR, associate professor of Radiology, Wayne State University School of Medicine and radiologist at the NCVAC, there was a documented increase in pleural plaques, causing erosion on the interior wall of the ribs. 

“This action of the pleural plaque against the covering of the bone and the bone itself is a biologically plausible and an anatomically logical explanation of the unrelenting pain which some patients experience,” said Dr. Harbut.

This new imaging approach involves enhancing images obtained on the 64-slice high resolution CT scan using the Vitrea(R) imaging software program by Vital Images. By using this imaging approach, Dr. Harbut was able to demonstrate that: 

Evidence based on the CT findings, the physical examination, pulmonary function studies, epidemiology and history of the patient’s intractable pleural pain meets the criteria for diagnosis of asbestosis. Combined with the known science of taconite dust, a link between the mine where the patient’s father worked and the patient’s disease was established.  

Due to the clarity and definition of this new imaging approach, it is more likely to detect asbestos-related diseases and cancer at an earlier stage.  

Earlier detection will allow the possibility for additional treatment options to manage the pain caused by pleural plaque beyond the narcotics often prescribed for patients with advanced stages of asbestos disease. This includes exploring other forms of traditional and nontraditional methods to control pain.  

The patient, studied since 2004 and currently 55 years of age, was exposed as a child to taconite dust unknowingly by her father, a taconite miner from 1962 – 1969, who carried the taconite dust on his work clothes. Taconite is used in the production of steel and road-patching material. It has been mined in Michigan and Minnesota. 

The patient has experienced increasing pain on her right side for the past 31 years, a persistent cough and wheezing. As the pain increased so did her medication. Using the new imaging approach, Dr. Harbut was able to show the progression of the patient’s pleural plaque over a three year period, from 2005 – 2008. The patient’s pleuritic pain, as well as the findings of her pulmonary function, physical exam and symptomology are consistent with those diagnosed with asbestosis and pleural plaques, as established by the American Thoracic Society.  

These findings also support earlier human and animal reports that dusts produced by taconite mining can evoke the same biological responses as do other fibers already defined as asbestos or asbestiform materials. 

Harbut added, “Patients often require a lifetime of narcotics to allow functioning, but we are hopeful that with this new imaging technology, more selective pain management approaches with fewer side effects can be instituted resulting in a better quality of life.”

Finally, the report supports the identification of taconite, which has not yet been categorized as asbestos but causes a disease consistent with asbestosis, and recommends a reevaluation of the definition of asbestos. This is especially important within the context of legislative efforts to prohibit the use of asbestos. 

Karmanos scientists are continuing their series of patient studies and will submit similar findings for peer review later this summer.  

In addition to Dr. Harbut, co-authors of the report include Carmen Endress, M.D., FACR; John J. Graff, Ph.D., MS, assistant professor, Wayne State University School of Medicine, and chief, Cancer Surveillance Research at the Barbara Ann Karmanos Cancer Institute; Christopher Weis, Ph.D., National Enforcement Investigations Center, United States Environmental Protection Agency; and Harvey Pass, M.D., director, New York University’s Division of Thoracic Surgery.  

About the National Center for Vermiculite and Asbestos-Related Cancers (NCVAC at Karmanos)  

In response to the United States Environmental Protection Agency’s (EPA) identification of major sources of public asbestos exposure in Michigan, and to address the need for early diagnosis and aggressive treatment of asbestos-related diseases, the Barbara Ann Karmanos Cancer Institute and the Center for Occupational and Environmental Medicine (COEM) affiliated with Wayne State University established Karmanos’ National Center for Vermiculite and Asbestos-Related Cancers. The NCVAC is co-directed by Michael Harbut, M.D., MPH, Karmanos Cancer Institute and Chief of the Center for Occupational and Environmental Medicine; and John J. Graff, Ph.D. MS, chief of Cancer Surveillance Research, Karmanos Cancer Institute and assistant professor, Department of Family Medicine and Public Health Sciences, Wayne State University School of Medicine. 

Reference: Barbara Ann Karmanos Cancer Institute, International Journal of Occupational and Environmental Health Features Discovery of Asbestos-Related Pain Origin from Scientists at the Karmanos Cancer Institute in Detroit , US Newswire, DETROIT, July 20, 2009.

A group of chemists from the University of Santiago de Compostela (USC) has developed a method to quantify the fragrance allergens found in baby bathwater. The researchers have analysed real samples and detected up to 15 allergen compounds in cosmetics and personal hygiene products. 

A team of scientists from the Department of Analytical Chemistry, Nutrition and Bromatology at the USC has developed a method to detect and quantify the 15 most common fragrance allergens included in soap, gel, cologne and other personal hygiene products.   

“Applying the method to eight real samples obtained from the daily baths of a series of babies aged between six months and two years old, we discovered the presence of all the compounds under study in at least one of the samples,” co-author of the study published this month in Analytical and Bioanalytical Chemistry, María Llompart, explained to SINC. 

The scientists found at least six of the 15 compounds in all the samples. In some cases, concentrations were “extremely high”, exceeding 100ppm (parts per million = nanograms/millilitre). Some of the substances that appeared were benzyl salicylate, linalol, coumarin and hydroxycitronellal. 

“The presence and levels of these chemical agents in bathwater should be cause for concern,” Llompart said, “bearing in mind that babies spend up to 15 minutes or more a day playing in the bath and that they can absorb these and other chemicals not only through their skin, but also by inhalation and often ingestion, intentional or not.”

New Method to Detect Fragrances

Allergens were able to be detected due to the high level of sensitivity of the method, which for the first time applies the Solid-Phase Micro Extraction (SPME) technique to determining the ingredients of cosmetics and child hygiene products. This technique makes it possible to concentrate and isolate chemical components from a sample by absorbing them into fibres with a certain coating. 

The researchers have also employed gas chromatography to separate compounds and mass spectrometry to identify and measure the abundance of each of the fragrances. 

European regulations stipulate that the presence of such substances should be indicated on the label of the product when levels exceed a certain limit (0.1 or 0.01%, depending on the type of compound), but some associations believe these limits are excessively tolerant, particularly where child hygiene and baby and child care products are concerned. 

References: J. Pablo Lamas, Lucia Sánchez-Prado, Carmen Garcia-Jares y María Llompart. “Solid-phase microextraction gas chromatography-mass spectrometry determination of fragrance allergens in baby bathwater”. Analytical and Bioanalytical Chemistry 394 (5): 1399-1411, julio de 2009.