House dust mite reduction and avoidance measures for treating eczema.

PubMed

Nankervis, Helen; Pynn, Emma V; Boyle, Robert J; Rushton, Lesley; Williams, Hywel C; Hewson, Deanne M; Platts-Mills, Thomas

2015-01-19

Eczema is an inflammatory skin disease that tends to involve skin creases, such as the folds of the elbows or knees; it is an intensely itchy skin condition, which can relapse and remit over time. As many as a third of people with eczema who have a positive test for allergy to house dust mite have reported worsening of eczema or respiratory symptoms when exposed to dust. To assess the effects of all house dust mite reduction and avoidance measures for the treatment of eczema. We searched the following databases up to 14 August 2014: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library (2014, Issue 8), MEDLINE (from 1946), Embase (from 1974), LILACS (from 1982), and the GREAT database. We also searched five trials registers and checked the reference lists of included and excluded studies for further references to relevant studies. We handsearched abstracts from international eczema and allergy meetings. Randomised controlled trials (RCTs) of any of the house dust mite reduction and avoidance measures for the treatment of eczema, which included participants of any age diagnosed by a clinician with eczema as defined by the World Allergy Organization. We included all non-pharmacological and pharmacological interventions that sought to reduce or avoid exposure to house dust mite and their allergenic faeces. The comparators were any active treatment, no treatment, placebo, or standard care only. Two authors independently checked the titles and abstracts identified, and there were no disagreements. We contacted authors of included studies for additional information. We assessed the risk of bias using Cochrane methodology. We included seven studies of 324 adults and children with eczema. Overall, the included studies had a high risk of bias. Four of the seven trials tested interventions with multiple components, and three tested a single intervention. Two of the seven trials included only children, four included children and adults, and one

Early life rhinovirus infection exacerbates house-dust-mite induced lung disease more severely in female mice.

PubMed

Phan, Jennifer A; Kicic, Anthony; Berry, Luke J; Sly, Peter D; Larcombe, Alexander N

2016-01-01

Recent studies have employed animal models to investigate links between rhinovirus infection and allergic airways disease, however, most do not involve early life infection, and none consider the effects of sex on responses. Here, we infected male and female mice with human rhinovirus 1B (or control) on day 7 of life. Mice were then subjected to 7 weeks of exposure to house-dust-mite prior to assessment of bronchoalveolar inflammation, serum antibodies, lung function, and responsiveness to methacholine. There were significant differences in responses between males and females in most outcomes. In males, chronic house-dust-mite exposure increased bronchoalveolar inflammation, house-dust-mite specific IgG1 and responsiveness of the lung parenchyma, however, there was no additional impact of rhinovirus infection. Conversely, in females, there were additive and synergistic effects of rhinovirus infection and house-dust-mite exposure on neutrophilia, airway resistance, and responsiveness of the lung parenchyma. We conclude that early life rhinovirus infection influences the development of house-dust-mite induced lung disease in female, but not male mice.

A NEW HOUSE DUST COLLECTION SYSTEM AND ITS USE IN A STUDY OF ASTHMA IN DUST MITE SENSITIVE CHILDREN IN RALEIGH, NORTH CAROLINA

EPA Science Inventory

A prototype dust collection system, the House Dust Vacuum One (HDVI), was designed for use in a study to investigate the relationship between house dust mite antigen levels and the presence of asthma in dust mite sensitive children. The HDVI was designed for the collection of dus...

Effects of physical interventions on house dust mite allergen levels in carpet, bed, and upholstery dust in low-income, urban homes.

PubMed Central

Vojta, P J; Randels, S P; Stout, J; Muilenberg, M; Burge, H A; Lynn, H; Mitchell, H; O'Connor, G T; Zeldin, D C

2001-01-01

House dust mite allergen exposure is a postulated risk factor for allergic sensitization, asthma development, and asthma morbidity; however, practical and effective methods to mitigate these allergens from low-income, urban home environments remain elusive. The purpose of this study was to assess the feasibility and effectiveness of physical interventions to mitigate house dust mite allergens in this setting. Homes with high levels of house dust mite allergen (Der f 1 + Der p 1 > or = 10 microg/g dust by enzyme-linked immunosorbent assay) in the bed, bedroom carpet, and/or upholstered furniture were enrolled in the study. Carpets and upholstered furniture were subjected to a single treatment of either dry steam cleaning plus vacuuming (carpet only) or intensive vacuuming alone. Bed interventions consisted of complete encasement of the mattress, box spring, and pillows plus either weekly professional or in-home laundering of nonencased bedding. Dust samples were collected at baseline and again at 3 days (carpet and upholstery only) and 2, 4, and 8 weeks posttreatment. We compared pretreatment mean allergen concentrations and loads to posttreatment values and performed between-group analyses after adjusting for differences in the pretreatment means. Both dry steam cleaning plus vacuuming and vacuuming alone resulted in a significant reduction in carpet house dust mite allergen concentration and load (p < 0.05). Levels approached pretreatment values by 4 weeks posttreatment in the intensive vacuuming group, whereas steam cleaning plus vacuuming effected a decrease that persisted for up to 8 weeks. Significant decreases in bed house dust mite allergen concentration and load were obtained in response to encasement and either professional or in-home laundering (p < 0.001). Between-group analysis revealed significantly less postintervention house dust mite allergen load in professionally laundered compared to home-laundered beds (p < 0.05). Intensive vacuuming and dry

Inactivation of dust mites, dust mite allergen, and mold from carpet.

PubMed

Ong, Kee-Hean; Lewis, Roger D; Dixit, Anupma; MacDonald, Maureen; Yang, Mingan; Qian, Zhengmin

2014-01-01

Carpet is known to be a reservoir for biological contaminants, such as dust mites, dust mite allergen, and mold, if it is not kept clean. The accumulation of these contaminants in carpet might trigger allergies or asthma symptoms in both children and adults. The purpose of this study is to compare methods for removal of dust mites, dust mite allergens, and mold from carpet. Carpets were artificially worn to simulate 1 to 2 years of wear in a four-person household. The worn carpets were inoculated together with a common indoor mold (Cladosporium species) and house dust mites and incubated for 6 weeks to allow time for dust mite growth on the carpet. The carpets were randomly assigned to one of the four treatment groups. Available treatment regimens for controlling carpet contaminants were evaluated through a literature review and experimentation. Four moderately low-hazard, nondestructive methods were selected as treatments: vacuuming, steam-vapor, Neem oil (a natural tree extract), and benzalkonium chloride (a quaternary ammonium compound). Steam vapor treatment demonstrated the greatest dust mite population reduction (p < 0.05) when compared to other methods. The two physical methods, steam vapor and vacuuming, have no statistically significant efficacy in inactivating dust mite allergens (p = 0.084), but have higher efficacy when compared to the chemical method on dust mite allergens (p = 0.002). There is no statistically significant difference in the efficacy for reducing mold in carpet (p > 0.05) for both physical and chemical methods. The steam-vapor treatment effectively killed dust mites and denatured dust mite allergen in the laboratory environment.

Sublingual immunotherapy in patients with house dust mite allergic rhinitis: prospective study of clinical outcomes over a two-year period.

PubMed

Soh, J Y; Thalayasingam, M; Ong, S; Loo, E X L; Shek, L P; Chao, S S

2016-03-01

Sublingual immunotherapy in patients with allergic rhinitis sensitised to house dust mites is safe, but its efficacy is controversial and sublingual immunotherapy with Blomia tropicalis has not yet been studied. This study sought to evaluate the efficacy of sublingual immunotherapy with house dust mite extract in children and adults with house dust mite allergic rhinitis over a period of two years. A prospective observational study was conducted of children and adults diagnosed with house dust mite allergic rhinitis who were treated with sublingual immunotherapy from 2008 to 2012. Total Nasal Symptom Scores, Mini Rhinoconjunctivitis Quality of Life scores and medication usage scores were assessed prospectively. Thirty-nine patients, comprising 24 children and 15 adults, were studied. Total Nasal Symptom Scores and Mini Rhinoconjunctivitis Quality of Life scores dropped significantly at three months into therapy, and continued to improve. Medication usage scores improved at one year into immunotherapy. Sublingual immunotherapy with house dust mite extracts, including B tropicalis, is efficacious as a treatment for patients with house dust mite allergic rhinitis.

The effect of sub-floor heating on house-dust-mite populations on floors and in furniture.

PubMed

de Boer, Rob

2003-01-01

It is well known that dehydrating conditions for house dust mites can be created by simply raising the temperature, causing loss of body water and eventually death. Thus, it can be expected that conditions for dust mites are less favourable on floors supplied with sub-floor heating. This was examined in a study of 16 houses with sub-floor heating and 21 without. The pattern of changes in air humidity and temperature on the floors was investigated and compared to known data of the tolerance of dust mites. Also the resident mite populations were compared. Floors with sub-floor heating had, on average, fewer mites, but the difference with unheated floors was small. It was remarkable that mite numbers were also lower in upholstered furniture. Another important observation was that some houses with sub-floor heating had high mite numbers, indicating that this type of heating is compatible with a thriving mite population. Temperature and humidity conditions of heated floors may allow mites not only to survive, but also to remain active in winter. A moderate increase in temperature, a moderate decrease in (absolute) air humidity, or a combination of both, will suffice to keep the humidity all winter below the Critical Equilibrium Humidity, the level of air humidity that is critical for mite growth and reproduction, hence for allergen production. However, it is argued that measures to suppress allergen production by house dust mites are likely to be far more effective if taken in summer rather than in winter.

House dust and storage mite contamination of dry dog food stored in open bags and sealed boxes in 10 domestic households.

PubMed

Gill, Christina; McEwan, Neil; McGarry, John; Nuttall, Tim

2011-04-01

Dry pet food is a potential source of exposure to house dust and storage mite allergens in canine atopic dermatitis. This study evaluated contamination of house dust and dry dog food stored in paper bags, sealable plastic bags and sealable plastic boxes in 10 households for 90 days using Acarex(®) tests for guanine, a Der p 1 ELISA and mite flotation. Acarex(®) tests were negative in all the food samples but positive in all the house dust samples. The Der p 1 levels and mite numbers significantly increased in food from paper bags (P = 0.0073 and P = 0.02, respectively), but not plastic bags or boxes. Mite numbers and Der p 1 levels were 10-1000 times higher in house dust than the corresponding food samples (P < 0.0001). There were significant correlations between Der p 1 in house dust and food from the paper (P < 0.0001) and plastic bags (P = 0.003), and mite numbers in house dust and food from the paper bags (P = 0.0007). Bedding and carpets were significantly associated with Der p 1 levels in house dust (P = 0.015 and P = 0.01, respectively), and food from the paper (both P = 0.02) and plastic bags (P = 0.03 and P = 0.04, respectively). Mites were identified in six of 10 paper bag, three of 10 plastic bag, one of 10 plastic box and nine of 10 house dust samples. These comprised Dermatophagoides (54%), Tyrophagus (10%; all from food) and unidentified mites (36%). Storage of food in sealable plastic boxes largely prevented contamination for 3 months. Exposure to mites and mite proteins in all the stored food, however, appeared to be trivial compared with house dust. © 2010 The Authors. Journal compilation © 2010 ESVD and ACVD.

Assessment of cross-reactivity among five species of house dust and storage mites.

PubMed

Saridomichelakis, Manolis N; Marsella, Rosanna; Lee, Kenneth W; Esch, Robert E; Farmaki, Rania; Koutinas, Alexander F

2008-04-01

In vitro cross-reactivity among two house dust (Dermatophagoides farinae, D. pteronyssinus) and three storage (Acarus siro, Tyrophagus putrescentiae, Lepidoglyphus destructor) mites was examined in 20 mite-sensitive dogs with natural occurring atopic dermatitis (group A), 13 high-IgE beagles experimentally sensitized to D. farinae (group B), and five healthy beagles (group C). Intradermal testing (IDT) and serology for allergen-specific IgE demonstrated that co-sensitization for all possible pairs of the five mites was generally 45% or higher among group A dogs. In the same dogs, enzyme-linked immunosorbent assay cross-inhibition results indicated that each one of D. farinae, A. siro and T. putrescentiae was a strong inhibitor of all the remaining mites, whereas D. pteronyssinus was a strong inhibitor of L. destructor. A high number of positive IDT and serology test results for D. pteronyssinus, A. siro, T. putrescentiae and L. destructor were recorded among group B dogs. No conclusive evidence of exposure to these mites was found upon analysis of dust samples from their environment and their food for the presence of mites and guanine. Also, the number of positive test results was generally higher among group B than among group C dogs. Enzyme-linked immunosorbent assay cross-inhibition revealed that D. farinae was a strong inhibitor of D. pteronyssinus, A. siro and T. putrescentiae. Collectively, these results demonstrated extensive in vitro cross-reactivity among house dust and/or storage mites that can explain false-positive results upon testing of dust mite-sensitive dogs with atopic dermatitis.

House-Dust Allergy

PubMed Central

Johnson, C. A.

1982-01-01

House-dust allergy is a common cause of perennial allergic rhinitis and extrinsic asthma. Symptoms tend to be worse when the patient is in bed. A positive skin test properly performed and interpreted confirms the diagnosis. The house-dust mite is the most important antigenic component of house-dust. Treatment consists of environmental control directed at reducing the mite content of bedroom dust, plus control of symptoms with drugs. Immunotherapy is controversial. ImagesFig. 1 PMID:21286201

Assessing the efficacy of a novel temperature and humidity control machine to minimize house dust mite allergen exposure and clinical symptoms in allergic rhinitis children sensitized to dust mites: a pilot study.

PubMed

Manuyakorn, Wiparat; Padungpak, Savitree; Luecha, Orawin; Kamchaisatian, Wasu; Sasisakulporn, Cherapat; Vilaiyuk, Soamarat; Monyakul, Veerapol; Benjaponpitak, Suwat

2015-06-01

House dust mite avoidance is advised in dust mite sensitized patients to decrease the risk to develop allergic symptoms. Maintaining a relative humidity (RH) of less than 50% in households is recommended to prevent dust mite proliferation. To investigate the efficacy of a novel temperature and humidity machine to control the level of dust mite allergens and total nasal symptom score (TNSS) in dust mite sensitized allergic rhinitis children. Children (8-15 years) with dust mite sensitized persistent allergic rhinitis (AR) were enrolled. The temperature and humidity control machine was installed in the bedroom where the enrolled children stayed for 6 months. TNSS was assessed before and every month after machine set up and the level of dust mite allergen (Der p 1 and Der f 1) from the mattress were measured before and every 2 months after machine set up using enzyme-linked immunosorbent assay (ELISA). A total of 7 children were enrolled. Noticeable reduction of Der f 1 was observed as early as 2 months after installing the machine, but proper significant differences appeared 4 months after and remained low until the end of the experiment (p <0.05). Although no correlation was observed between TNSS and the level of dust mite allergens, there was a significant reduction in TNSS at 2 and 4 months (p <0.05) and 70% of the patients were able to stop using their intranasal corticosteroids by the end of the experiment. The level of house dust mite in mattresses was significantly reduced after using the temperature and humidity control machine. This machine may be used as an effective tool to control clinical symptoms of dust mite sensitized AR children.

Levels of house dust mite allergen in cars.

PubMed

Mason, Howard J; Smith, Ian; Anua, Siti Marwanis; Tagiyeva, Nargiz; Semple, Sean; Devereux, Graham

2015-09-01

This small study investigated house dust mite (HDM) allergen levels in cars and their owners' homes in north-east Scotland. Dust samples from twelve households and cars were collected in a standardised manner. The dust samples were extracted and measured for the Dermatophagoides group 2 allergens (Der p 2 and Der f 2) and total soluble protein. Allergen levels at homes tended to be higher than in the cars, but not significantly. However, they significantly correlated with paired car dust samples expressed either per unit weight of dust or soluble protein (rho=0.657; p=0.02 and 0.769; p=0.003, respectively). This points to house-to-car allergen transfer, with the car allergen levels largely reflecting levels in the owner's home. Car HDM allergen levels were lower than those reported in Brazil and the USA. Twenty-five percent of the houses and none of the cars had allergen levels in dust greater than 2000 ng g(-1). This value is often quoted as a threshold for the risk of sensitisation, although a number of studies report increased risk of sensitisation at lower levels. This small study does not allow for characterisation of the distribution of HDM allergen in vehicles in this geographic area, or of the likely levels in other warmer and more humid areas of the UK. Cars and other vehicles are an under-investigated micro-environment for exposure to allergenic material.

Comparative efficacy of house dust mite extermination products.

PubMed

Schober, G; Kniest, F M; Kort, H S; De Saint Georges Gridelet, D M; Van Bronswijk, J E

1992-06-01

The acaricidal efficacy of nine marketed products, i.e. Acardust, Acarosan (foam and powder), Actelic 50, Artilin 3A (spirit and water base), liquid nitrogen, Paragerm AK, and Tymasil, and of intensive vacuum-cleaning have been compared on four different test surfaces: mattress, tufted carpet, gypsum board and rough wooden board, all covered with artificial house dust. They were inoculated with the house dust mite, Dermatophagoides pteronyssinus or the house-dust fungus Aspergillus repens for evaluation of the fungistatic claims of some products. The acaricidal activity of Tymasil did not surpass that of vacuuming; its fungistatic effect was not apparent. The other products showed complete to almost complete eradication on at least one of the substrates tested. Taking into account the results of acaricidal efficacy as well as the data on safety and practicality acquired earlier, Acarosan powder was considered first choice for carpet treatment. Acarosan and liquid nitrogen, were found to be effective in the treatment of mattress, pillow, upholstered furniture and heavy curtains. On wooden surfaces Acarosan was found to be both effective and safe, while Acardust, Actelic 50, Artilin 3A (both fungistatic as well as acaricidal), liquid nitrogen and Paragerm also passed the efficiency test.

House dust and forage mite allergens and their role in human and canine atopic dermatitis.

PubMed

Nuttall, T J; Hill, Peter B; Bensignor, E; Willemse, T

2006-08-01

This article reviews the literature regarding the role of house dust and forage mite allergens in canine atopic dermatitis. The presence of immunoglobulin E (IgE) to these mites, especially to Dermatophagoides farinae, is common in both normal and atopic dogs. Exposure of dogs to the different mites is described both in the direct environment and in the coat of animals for house dust mites and in the food for forage mites. Allergens causing allergic disease in dogs seem to be different from those in humans. Dogs seem to react to high molecular weight allergens, compared to the low molecular weight group 1 and group 2 proteases that are commonly implicated in humans with atopic diseases. Despite numerous published studies dealing with this subject, a number of questions still need to be addressed to better understand the exact role of these mites in the pathogenesis of canine atopic dermatitis and to improve the quality of the allergens used in practice.

Indoor factors associated with concentrations of house dust mite allergen, Der p 1, in a random sample of houses in Norwich, UK.

PubMed

Luczynska, C; Sterne, J; Bond, J; Azima, H; Burney, P

1998-10-01

Studies of house dust mite allergen concentrations suggest large variations both within and between homes. It is likely that different household characteristics influence allergen levels in different locations within the house. To investigate household characteristics associated with higher concentrations of house dust mite allergen in a random sample of houses. Information on indoor environment was obtained from 158 adults aged 20-44. Dust samples were collected from their living room floor, bedroom floor and mattress. Concentrations of Der p 1, the major allergen from the house dust mite Dermatophagoides pteronyssinus, were measured by monoclonal antibody immunoassay. Associations between mite allergen concentrations and household characteristics were examined using censored-normal regression models. Factors that were related to Der p 1 (P houses. Geometric mean concentrations of Der p 1 were 1.9 microg/g in living room floor dust, 1.7 microg/g in bedroom floor dust and 2.0 microg/g in mattress dust. Approximately 25% of living room floor and mattress, and over 30% of bedroom floor samples had Der p 1 concentrations greater than 10 microg/g. Household characteristics associated with Der p 1 concentrations in both living room and bedroom were floor level, extractor fan in the kitchen, and age of carpet. Living room Der p 1 concentrations were also associated with gas oven/hob, window condensation, open fires, vacuum cleaner type, smokers in the house and age of house. Bedroom Der p 1 concentrations were also associated with use of blankets and wash temperature of bedding. Mattress Der p 1 concentrations were associated with window condensation, concrete bedroom floor and age of mattress. Different household characteristics were associated with high Der p 1 concentrations in different parts of the house. These findings are relevant

Ventilation in homes infested by house-dust mites.

PubMed

Sundell, J; Wickman, M; Pershagen, G; Nordvall, S L

1995-02-01

Thirty single-family homes with either high (> or = 2000 ng/g) or low (< or = 1000 ng/g) house-dust mite (HDM) allergen levels in mattress dust were examined for ventilation, thermal climate, and air quality (formaldehyde and total volatile organic compounds (TVOC). Elevated concentrations of HDM allergen in mattress and floor dust were associated with the difference in absolute humidity between indoor and outdoor air, as well as with low air-change rates of the home, particularly the bedroom. No correlation was found between concentration of TVOC or formaldehyde in bedroom air and HDM allergen concentration. In regions with a cold winter climate, the air-change rate of the home and the infiltration of outdoor air into the bedroom appear to be important for the infestation of HDM.

Early-life house dust mite allergens, childhood mite sensitization, and respiratory outcomes.

PubMed

Casas, L; Sunyer, J; Tischer, C; Gehring, U; Wickman, M; Garcia-Esteban, R; Lehmann, I; Kull, I; Reich, A; Lau, S; Wijga, A; Antó, J M; Nawrot, T S; Heinrich, J; Keil, T; Torrent, M

2015-07-01

Exposure to indoor allergens during early life may play a role in the development of the immune system and inception of asthma. To describe the house dust mite (HDM) allergen concentrations in bedroom dust during early life and to evaluate its associations with HDM sensitization, wheezing, and asthma, from birth to school age, in 5 geographically spread European birth cohorts. We included 4334 children from INMA-Menorca (Spain), BAMSE (Sweden), LISAplus and MAS (Germany), and PIAMA-NHS (the Netherlands). Dust samples were collected from bedrooms during early life and analyzed for Dermatophagoides pteronyssinus (Der p1) and Dermatophagoides farinae (Der f1). HDM concentrations were divided into four categories. Sensitization was determined by specific IgE. Wheezing and asthma information up to 8/10 years was collected through questionnaires. We performed mixed-effects logistic regression models and expressed associations as odds ratios with 95% confidence intervals. House dust mite concentrations varied across cohorts. Mean allergen concentrations were highest in INMA-Menorca (geometric mean (GM) Der p1 = 3.3 μg/g) and LISAplus (GM Der f1 = 2.1 μg/g) and lowest in BAMSE (GM Der p1 = 0.1 μg/g, Der f1 = 0.3 μg/g). Moderate and high HDM concentrations were significantly (P-values < 0.05) associated with 50-90% higher prevalence of HDM sensitization. No significant associations were observed with respiratory outcomes. Our study based on geographically spread regions, a large sample size, and a wide range of allergen concentration shows that HDM allergen concentrations vary across regions and that exposure during early life plays a role in the development of allergic sensitization but not in the development of respiratory outcomes. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Clinical investigation of basophil activation test as a complementary test for house dust mite allergen].

PubMed

Ren, H L; Li, J D; Miao, Y H; Xu, T

2018-03-01

Objective: To investigate the clinical application of glass micro fiber basophil activation test (BAT) used as a complementary test for house dust mite allergen. Method: Forty patients with clinical diagnosed allergic rhinitis was test by three methods for house dust mite allergen, skin prick test(SPT),Immuno CAP sIgE, and BAT in vitro. The sensitivity and specificity of glass micro fiber were accessed, and the consistency between BAT, SPT, and Immuno sIgE was analyzed. As in vivo provocation was not performed, gold standard is regarded as the combination of medical history and positive reports of SPT and/or ImmunoCAP sIgE test. Result: Twentythree patients are diagnosed as house dust mite allergic rhinitis by gold standard. The sensitivity and specificity of glass micro fiber BAT were 60.9% and 88.2%, the sensitivity of SPT and sIgE was 87.0% and sIgE 73.9%. The correlation rates between BAT with SPT is 0.67( P <0.05), and sIgE 0.55( P <0.05). The accuracy, predictive value of positive and negative of BAT are 0.47,60.9%,88.2%.The Kappa values of BAT, SPT and sIgE with gold standard are 0.47,0.86,0.71. Conclusion: As a complementary test for house dust mite allergic rhinitis, BAT have a good consistency with SPT and sIgE, while as it has only moderate consistency with "gold standard", further studies are needed to prove its clinical significance. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

Effect of asthma management education program on stress and compliance of patients with allergic asthma to house dust mite.

PubMed

Yoo, Yang Sook; Cho, Ok Hee; Kim, Eun Sin; Jeong, Hye Sun

2005-06-01

This study was designed to examine the effect of asthma management education program applied to allergic asthma patients receiving immunotherapy due to house dust mite on their stress and compliance with health care regimens. A quasi experimental design with non-equivalent control group and non-synchronized design was used. The subjects of this study were 61 patients who were receiving immunotherapy at intervals of a week after their symptoms were diagnosed as house dust mite allergic asthma at the pulmonary department of a university hospital in Seoul. They were divided into an experimental group of 29 patients who received asthma management education and a control group of 32 patients. The asthma management education program was composed of group education (once) and reinforcement education (three times) with environmental therapy and immunotherapy to house dust mite. Stress significantly decreased in the experimental group compared to that in the control group. Compliance with health care regimens significantly increased in the experimental group compared to that in the control group. The results suggested that the asthma management education program is effective for the management of stress and the improvement of compliance in patients with allergic asthma to house dust mite.

House Dust Mite Prevalence in the House of Patients with Atopic Dermatitis in Mashhad, Iran.

PubMed

Ziyaei, Toktam; Berenji, Fariba; Jabbari-Azad, Farahzad; Fata, Abdolmajid; Jarahi, Lida; Fereidouni, Mohammad

2017-06-01

Being exposed to house dust mites intensifies atopic dermatitis. This study has investigated the contamination rate with Dermatophagoides mites in patient's residential home with atopic dermatitis. In this cross-sectional study, 40 patients took part with atopic dermatitis (positive or negative for mites by prick Dermal Test). Samples were collected from 3 locations (living room, bedroom and bed) by vacuum cleaner. Dust samples (transferred to freezer -20 °C) were examined by direct method and flotation. The data were analyzed using statistical SPSS vr.20 software. Twenty patients of positive prick test included 8 (40%) male and 12 (60%) female. The results of direct observation of mites: 7 cases (35%) in bedding sheets, 6 cases (30%) bedrooms' carpet, 3 cases (15%) living room's carpet. Twenty patients of negative prick test included 8 (40%) male and 12 (60%) female. Only mites were found (5%) in living room's carpets of negative prick test patients. Dermatophagoides pteronyssinus was more frequent than Dermatophagoides farina e. (98% vs 83%). Fifty-five percent of residential homes of prick test positive patients and only 5% of residential homes of prick test negative patients were positive for mite. Sunshine provided home had fewer mites than home where sunshine is not provided. Prick test positive patients used handmade carpets more than machine made ones. In positive prick test patients, mites were found in bed sheet and bedroom's carpet more than negative prick test patient's sheets and carpets.

Specific immunotherapy for rhinitis and asthma with a subcutaneous hypoallergenic high-dose house dust mite extract: results of a 9-month therapy.

PubMed

El-Qutob, David; Moreno, Francisco; Subtil-Rodríguez, Alicia

2016-07-01

Effectiveness of a 9-month specific immunotherapy with a subcutaneous hypoallergenic high-dose house dust mite extract to reduce allergic symptoms as perceived by patients and physicians was assessed. An observational, retrospective, multicenter study was carried out in patients diagnosed with asthma and/or rhinitis caused by house dust mites having started specific immunotherapy with Acaroid(®). Primary end point was perceived effectiveness. A total of 409 patients were included. According to physician-completed visual analogue scale, a 58.1% clinical improvement was observed. Patient-completed visual analogue scale showed a 69.8% clinical improvement. The need for unscheduled/emergency healthcare, as an indication of poor quality of life, showed a significant reduction. Our results confirm in a real-world setting the findings from randomized clinical trials of high-dose house dust mites allergoid immunotherapy with a subcutaneous hypoallergenic high-dose house dust mite extract.

A Three-Year Course of House Dust Mite Sublingual Immunotherapy Appears Effective in Controlling the Symptoms of Allergic Rhinitis.

PubMed

Novakova, Silviya M; Novakova, Plamena I; Yakovliev, Plamen H; Staevska, Maria T; Mateva, Nonka G; Dimcheva, Teodora D; Peichev, Jivko L

2018-05-01

Background Allergic rhinitis is the most common allergic disorder. Although the management of the disease is successful in many patients, based on guidelines, some of them remain with symptoms uncontrolled with pharmacotherapy. Presently, there is no substantiated information on the control of allergic rhinitis in patients who underwent sublingual immunotherapy. Objective The purpose of this prospective follow-up study was to assess the control of allergic rhinitis in adults after a three-year course of house dust mite sublingual immunotherapy. Methods This prospective real-life study was designed to include adults with moderate to severe allergic rhinitis sensitized to house dust mite who underwent a three-year course of sublingual immunotherapy. Control of symptoms was assessed by Rhinitis Control Assessment Test (RCAT) after three years of house dust mite sublingual immunotherapy. Additionally, patients assessed their symptoms by utilizing a visual analog scale. Results A total number of 86 consecutively enrolled patients (46 (53.49%) men; mean age 26.10 years (SD = 5.85)) with moderate to severe allergic rhinitis and clinically relevant sensitization to house dust mite were evaluated. When assessed by RCAT on the third year, 74 (86.05%) had well-controlled symptoms and 20 (27.03%) of them were completely controlled. A significant reduction in visual analog scale scores-from 7.52 cm at baseline to 2.31 cm-was established ( P < 0.0001). There was a strong negative correlation between RCAT scores and visual analog scale (r = -0.65; P < 0.01). Conclusion This study provided evidence that a three-year course of house dust mite sublingual immunotherapy appears effective in controlling the symptoms of allergic rhinitis.

House Dust Mite Prevalence in the House of Patients with Atopic Dermatitis in Mashhad, Iran

PubMed Central

Ziyaei, Toktam; Berenji, Fariba; Jabbari-Azad, Farahzad; Fata, Abdolmajid; Jarahi, Lida; Fereidouni, Mohammad

2017-01-01

Background: Being exposed to house dust mites intensifies atopic dermatitis. This study has investigated the contamination rate with Dermatophagoides mites in patient’s residential home with atopic dermatitis. Methods: In this cross-sectional study, 40 patients took part with atopic dermatitis (positive or negative for mites by prick Dermal Test). Samples were collected from 3 locations (living room, bedroom and bed) by vacuum cleaner. Dust samples (transferred to freezer −20 °C) were examined by direct method and flotation. The data were analyzed using statistical SPSS vr.20 software. Results: Twenty patients of positive prick test included 8 (40%) male and 12 (60%) female. The results of direct observation of mites: 7 cases (35%) in bedding sheets, 6 cases (30%) bedrooms’ carpet, 3 cases (15%) living room’s carpet. Twenty patients of negative prick test included 8 (40%) male and 12 (60%) female. Only mites were found (5%) in living room’s carpets of negative prick test patients. Dermatophagoides pteronyssinus was more frequent than Dermatophagoides farinae. (98% vs 83%). Conclusion: Fifty-five percent of residential homes of prick test positive patients and only 5% of residential homes of prick test negative patients were positive for mite. Sunshine provided home had fewer mites than home where sunshine is not provided. Prick test positive patients used handmade carpets more than machine made ones. In positive prick test patients, mites were found in bed sheet and bedroom’s carpet more than negative prick test patient’s sheets and carpets. PMID:29062855

Occurrence of Respiratory Symptoms Resulting from Exposure to House Dust Mites in Early Childhood

ERIC Educational Resources Information Center

Jedrychowski, Wieslaw; Maugeri, Umberto; Zembala, Marek; Hajto, Barbara; Flak, Elzbieta; Mroz, Elzbieta; Jacek, Ryszard; Sowa, Agata; Perera, Frederica P.

2009-01-01

The aim of the study was to describe the distribution of house dust mite (HDM) allergens within homes of three-year-old children, to identify factors responsible for its variation and to test the hypothesis whether the content of HDM allergens exceeding 2 [mu]g/g dust may be regarded as a risk level of sensitization possibly affecting respiratory…

The role of water temperature and laundry procedures in reducing house dust mite populations and allergen content of bedding.

PubMed

McDonald, L G; Tovey, E

1992-10-01

The effects of various laundry procedures on house dust mites and their allergens have been established. All mites were killed by water temperatures 55 degrees C or greater. Killing at lower temperatures was not enhanced by any of the pure detergents or laundry products tested. A cold cycle of laundry washing with or without laundry powder did not remove most live mites from bedding, however, the allergen concentration (Der p I/gm fine dust) was reduced by more than 90%. Dry cleaning did not reduce the allergen concentration of the dust, although most, if not all, mites were killed.

Prevalence of house dust mite allergens in low-income homes with evaporative coolers in a semiarid climate.

PubMed

Johnston, James D; Barney, Taylor P; Crandall, Justin H; Brown, Marinn A; Westover, Tarah R; Paulson, Sterling M; Smith, Madeleine S; Weber, K Scott

2018-01-02

House dust mites are typically absent in homes in arid and semiarid climates due to low humidity. Evaporative "swamp" cooling significantly increases indoor humidity in dry climates and is suspected of promoting dust mite survival in these regions. We investigated the prevalence and concentration of mite allergens in dust from low-income homes (N = 22) with evaporative coolers in Utah County, Utah. Overall, 15 homes (68.2%) were positive for either Der p 1 or Der f 1 in at least 1 location. Geometric mean allergen levels in mattresses were 0.107 and 0.087 ug/g dust for Der p 1 and Der f 1, respectively. In furniture, levels were 0.143 and 0.165 ug/g dust for Der p1 and Der f 1, respectively. The percentage of positive homes in this study was much higher than previously reported in larger homes with swamp coolers in the same community. These results suggest socioeconomic factors may play a role in dust mite allergen prevalence in homes with evaporative coolers in dry climates.

Effect on quality of life of the mixed house dust mite/weed pollen extract immunotherapy.

PubMed

Li, Lisha; Guan, Kai

2016-07-01

Although many patients with allergic rhinitis have symptoms due to sensitization to more than one kind of allergens, and mixed allergen extracts are widely used for immunotherapy, there are few published trials. Our study aimed to evaluate the effect of multiple-allergen immunotherapy on improving the symptoms and quality of life of allergic rhinitis patients. We performed a 1-year single-center observation study of subcutaneous immunotherapy using house dust mite extract (n = 12), weed pollen extract (n = 21), or mixed house dust mite/weed pollen extract (n = 11) in 44 allergic rhinitis patients. All the allergens responsible for the symptom of each patient were included in his immunotherapy. Symptom score, medication score, and quality of life of the patients were evaluated before and after 1-year immunotherapy. Quality of life was evaluated with the Rhinoconjunctivitis Quality of Life Questionnaire. In all 3 groups receiving subcutaneous immunotherapy, significant improvement of symptom score, medication score, and quality of life was found vs. baseline at 1 year, irrespective of the allergen used. In the weed pollen season, the changes of quality of life questionnaire score after 1-year treatment were not significantly different between the weed pollen group (1.55 ± 1.24) and the mixed house dust mite/weed pollen group (1.14 ± 1.01). The same happened in the nonpollen seasons, during which dust mite immunotherapy (1.23 ± 1.63) and mixed immunotherapy (0.60 ± 0.47) did not show significantly different effect on the quality of life. The multiple-allergen immunotherapy might be effective in polysensitized allergic rhinitis patients, and could improve their quality of life. Our result did not show significant difference between the effects of multiple-allergen immunotherapy and mono-allergen immunotherapy.

The Allergen Der p3 from House Dust Mite Stimulates Store-Operated Ca2+ Channels and Mast Cell Migration through PAR4 Receptors.

PubMed

Lin, Yu-Ping; Nelson, Charmaine; Kramer, Holger; Parekh, Anant B

2018-04-19

The house dust mite is the principal source of perennial aeroallergens in man. How these allergens activate innate and adaptive immunity is unclear, and therefore, there are no therapies targeting mite allergens. Here, we show that house dust mite extract activates store-operated Ca 2+ channels, a common signaling module in numerous cell types in the lung. Activation of channel pore-forming Orai1 subunits by mite extract requires gating by STIM1 proteins. Although mite extract stimulates both protease-activated receptor type 2 (PAR2) and PAR4 receptors, Ca 2+ influx is more tightly coupled to the PAR4 pathway. We identify a major role for the serine protease allergen Der p3 in stimulating Orai1 channels and show that a therapy involving sub-maximal inhibition of both Der p3 and Orai1 channels suppresses mast cell activation to house dust mite. Our results reveal Der p3 as an important aeroallergen that activates Ca 2+ channels and suggest a therapeutic strategy for treating mite-induced asthma. Copyright © 2018 Elsevier Inc. All rights reserved.

Acaricidal activities of some essential oils and their monoterpenoidal constituents against house dust mite, Dermatophagoides pteronyssinus (Acari: Pyroglyphidae)

PubMed Central

Saad, El-Zemity; Hussien, Rezk; Saher, Farok; Ahmed, Zaitoon

2006-01-01

The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different time intervals 24 and 48 h under laboratory conditions. In general, it was noticed that the acaricidal effect based on LC 50 of either essential oils or monoterpenoids against the mite was time dependant. The LC 50 values were decreased by increasing of exposure time. Clove, matrecary, chenopodium, rosemary, eucalyptus and caraway oils were shown to have high activity. As for the monoterpenoids, cinnamaldehyde and chlorothymol were found to be the most effective followed by citronellol. This study suggests the use of the essential oils and their major constituents as ecofriendly biodegradable agents for the control of house dust mite, D. pteronyssinus. PMID:17111463

Acaricidal activities of some essential oils and their monoterpenoidal constituents against house dust mite, Dermatophagoides pteronyssinus (Acari: Pyroglyphidae).

PubMed

Saad, El-Zemity; Hussien, Rezk; Saher, Farok; Ahmed, Zaitoon

2006-12-01

The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different time intervals 24 and 48 h under laboratory conditions. In general, it was noticed that the acaricidal effect based on LC(50) of either essential oils or monoterpenoids against the mite was time dependant. The LC(50) values were decreased by increasing of exposure time. Clove, matrecary, chenopodium, rosemary, eucalyptus and caraway oils were shown to have high activity. As for the monoterpenoids, cinnamaldehyde and chlorothymol were found to be the most effective followed by citronellol. This study suggests the use of the essential oils and their major constituents as ecofriendly biodegradable agents for the control of house dust mite, D. pteronyssinus.

Group 1 and 2 Dermatophagoides house dust mite allergens in the microenvironment of cats.

PubMed

Loft, Klaus Earl; Rosser, Edmund J

2010-04-01

House dust mite allergens (HDMAs) are some of the most common allergens associated with allergic diseases in humans and dogs. The purpose of this study was to determine whether HDMAs could be detected in cat-associated household microenvironments. From 50 cat-only households with 95 cats, dust samples were collected by vacuuming for 2 min m(-2) from three areas where cats slept or rested regularly from September to October 2006. Relative humidity and temperature were measured in each household using a data logger. Each owner completed a questionnaire on potential factors that might influence the prevalence of house dust mites (HDMs). Dust samples were analysed utilizing an ELISA for Der p 1, Der f 1 and HDM group 2 allergens. In 38 of 50 households there was greater than 2 microg g(-1) of dust for at least one HDMA. Using stepwise logistic regression, factors associated with increased HDMA levels included: free-standing houses, number of humans in household, longhaired cats and age of the cat. Factors associated with decreased HDMA concentrations included: forced air heating and central air conditioning, less than 50% carpeting of the home, use of flea control, cats suffering from dermatological disease and the average temperature of the household. Many sleeping/resting areas utilized by cats contain sufficiently high levels of HDMAs to be potential sources of sensitization. This finding should lead to further determination of the role of HDMs in cats suffering from putative allergic conditions such as atopic dermatitis or asthma.

Molecular identification of house dust mites and storage mites.

PubMed

Wong, Shew Fung; Chong, Ai Ling; Mak, Joon Wah; Tan, Jessie; Ling, Suk Jiun; Ho, Tze Ming

2011-10-01

Mites are known causes of allergic diseases. Currently, identification of mites based on morphology is difficult if only one mite is isolated from a (dust) sample, or when only one gender is found, or when the specimen is not intact especially with the loss of the legs. The purpose of this study was to use polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of the ITS2 gene, to complement the morphological data for the identification of mites to the species level. For this, six species were cultured: Dermatophagoides pteronyssinus, D. farinae, Blomia tropicalis, Tyrophagus putrescentiae, Aleuroglyphus ovatus and Glycycometus malaysiensis. Genomic DNA of the mites was extracted, quantified, amplified and digested individually with restriction enzymes. Hinf I and Ple I differentiated the restriction patterns of D. pteronyssinus and D. farinae. Bfa I and Alu I enzymes differentiated B. tropicalis and G. malaysiensis. Ple I enzyme was useful for the differentiation between T. putrescentiae and A. ovatus. Bfa I was useful for the differentiation of G. malaysiensis from the rest of the species. In conclusion, different species of mites can be differentiated using PCR-RFLP of ITS2 region. With the established PCR-RFLP method in this study, identification of these mites to the species level is possible even if complete and intact adult specimens of both sexes are not available. As no study to date has reported PCR-RFLP method for the identification of domestic mites, the established method should be validated for the identification of other species of mites that were not included in this study.

Sensitivity to House Dust Mites Allergens with Atopic Asthma and Its Relationship with CD14 C(-159T) Polymorphism in Patients of West Bengal, India.

PubMed

Ghosh, Amlan; Dutta, Shampa; Podder, Sanjoy; Mondal, Priti; Laha, Arghya; Saha, Nimai Chandra; Moitra, Saibal; Saha, Goutam Kumar

2018-01-10

India is the home to around 15-20 million asthmatics, and asthma prevalence is increasing in Indian metropolitan area, including Kolkata, West Bengal. Complex interactions of genetic and environmental factors are involved in asthma. Genome-wide search for susceptible loci regulating IgE response (atopy) have identified a candidate gene CD14 which is most important in the context of allergic responses of respiratory system. This study was aimed to investigate the role of house dust and house dust mites in development of bronchial asthma and to explore the possible association of candidate gene CD14 with disease manifestation among Kolkata patient population. Skin-prick test was done among 950 asthmatic patients against 8 aeroallergens, including house dust and house dust mites and total serum IgE and allergen-specific IgE were measured. Polymerase chain reaction-restriction fragment length polymorphism was done in patients and nonasthmatic control (n = 255 in each) to characterize a functional polymorphism, C(-159)T, of CD14, a positional candidate gene for allergy. We identified house dust as the most common aeroallergen sensitizer among atopic patients in Kolkata followed by Dermatophagoides pteronyssinus and Dermatophagoides farinae Hughes (Acari: Pyroglyphidae) mites. Patient's sera contain significantly higher IgE level than that of control. Allergen-specific IgE antibody test revealed that 76.36% patients had specific IgE antibody against D. pteronyssinus mite. There was a significant difference in the distribution of alleles and genotypes for CD14 polymorphism with an increase in disease severity. So, in Kolkata, house dust mite is a common aeroallergen and D. pteronyssinus is predominant among mites. The present study revealed that bronchial asthma has a genetic background. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The descriptive epidemiology of house dust mite-specific and total immunoglobin E in England using a nationally representative sample.

PubMed

Court, C S; Cook, D G; Strachan, D P

2002-07-01

Previous studies have shown that IgE levels vary according to factors such as age, gender and smoking but most studies have been small and none have been based on a nationally representative sample. To investigate the influence of epidemiological factors on serum total IgE and house dust mite-specific IgE levels. An interviewer-led questionnaire was carried out and blood samples taken from 24 952 people aged 11 and over as part of the 1995 and 1996 Health Surveys for England. Serum total IgE and house dust mite-specific IgE were measured. Both total and house dust mite-specific IgE were more frequently raised in men and in younger age groups. After adjusting for age and sex, raised total IgE was more common in current smokers and non-white ethnic groups and was not related to social class. The higher levels in non-white ethnic groups was not explained by smoking, urban living or being born outside the UK. Whilst total IgE levels declined in older age groups in non-smokers, among smokers they increased across successive age groups from 50 years onwards. In contrast, following adjustment for age and sex, raised house dust mite IgE was more common in non-manual workers and in some non-white ethnic groups but was not related to smoking. This large nationwide study provides further confirmation of differing epidemiological patterns for total serum IgE and allergen-specific sensitization. Indicative ranges for 'usual' values for a wide range of ages among men and women in England are given.

The Role of Dust Mites in Allergy.

PubMed

Miller, Jeffrey D

2018-06-23

House dust mites are an unsurpassed cause of atopic sensitization and allergic illness throughout the world. The major allergenic dust mites Dermatophagoides pteronyssinus, Dermatophagoides farinae, Euroglyphus maynei, and Blomia tropicalis are eight-legged members of the Arachnid class. Their approximately 3-month lifespan comprises egg, larval, protonymph, tritonymph, and adult stages, with adults, about one fourth to one third of a millimeter in size, being at the threshold of visibility. The geographic and seasonal distributions of dust mites are determined by their need for adequate humidity, while their distribution within substrates is further determined by their avoidance of light. By contacting the epithelium of the eyes, nose, lower airways, skin, and gut, the allergen-containing particles of dust mites can induce sensitization and atopic symptoms in those organs. Various mite allergens, contained primarily in mite fecal particles but also in shed mite exoskeletons and decaying mite body fragments, have properties that include proteolytic activity, homology with the lipopolysaccharide-binding component of Toll-like receptor 4, homology with other invertebrate tropomyosins, and chitin-cleaving and chitin-binding activity. Mite proteases have direct epithelial effects including the breaching of tight junctions and the stimulation of protease-activated receptors, the latter inducing pruritus, epithelial dysfunction, and cytokine release. Other components, including chitin, unmethylated mite and bacterial DNA, and endotoxin, activate pattern recognition receptors of the innate immune system and act as adjuvants promoting sensitization to mite and other allergens. Clinical conditions resulting from mite sensitization and exposure include rhinitis, sinusitis, conjunctivitis, asthma, and atopic dermatitis. Systemic allergy symptoms can also occur from the ingestion of cross-reacting invertebrates, such as shrimp or snail, or from the accidental ingestion of mite

Gene-by-environment effect of house dust mite on purinergic receptor P2Y12 (P2RY12) and lung function in children with asthma.

PubMed

Bunyavanich, S; Boyce, J A; Raby, B A; Weiss, S T

2012-02-01

Distinct receptors likely exist for leukotriene (LT)E(4), a potent mediator of airway inflammation. Purinergic receptor P2Y12 is needed for LTE(4)-induced airways inflammation, and P2Y12 antagonism attenuates house dust mite-induced pulmonary eosinophilia in mice. Although experimental data support a role for P2Y12 in airway inflammation, its role in human asthma has never been studied. To test for association between variants in the P2Y12 gene (P2RY12) and lung function in human subjects with asthma, and to examine for gene-by-environment interaction with house dust mite exposure. Nineteen single nucleotide polymorphisms (SNPs) in P2RY12 were genotyped in 422 children with asthma and their parents (n = 1266). Using family based methods, we tested for associations between these SNPs and five lung function measures. We performed haplotype association analyses and tested for gene-by-environment interactions using house dust mite exposure. We used the false discovery rate to account for multiple comparisons. Five SNPs in P2RY12 were associated with multiple lung function measures (P-values 0.006–0.025). Haplotypes in P2RY12 were also associated with lung function (P-values 0.0055–0.046). House dust mite exposure modulated associations between P2RY12 and lung function, with minor allele homozygotes exposed to house dust mite demonstrating worse lung function than those unexposed (significant interaction P-values 0.0028–0.040). The P2RY12 variants were associated with lung function in a large family-based asthma cohort. House dust mite exposure caused significant gene-by-environment effects. Our findings add the first human evidence to experimental data supporting a role for P2Y12 in lung function. P2Y12 could represent a novel target for asthma treatment.

The relative allergenicity of Stachybotrys chartarum compared to house dust mite extracts in a mouse model

EPA Science Inventory

A report by the Institute of Medicine suggested that more research is needed to better understand mold effects on allergic disease, particularly asthma development. The authors compared the ability of the fungus Stachybotrys chartarum (SCE) and house dust mite (HDM) extracts to i...

DIESEL AND CARBON PARTICLES ENHANCE HOUSE DUST MITE-INDUCED PULMONARY HYPERSENSITIVITY IN BROWN NORWAY RATS

EPA Science Inventory

Diesel and Carbon Particles Enhance House Dust Mite-Induced Pulmonary Hypersensitivity in Brown Norway Rats. P. Singh1, M.J. Daniels2, D. Winsett2, J. Richards2, K. Crissman2, M. Madden2 and M.I. Gilmour2. 1NCSU, Raleigh, NC and 2 USEPA, Research Triangle Park, NC.

Ep...

Ecological relationships between xerophilic fungi and house-dust mites (Acarida: Pyroglyphidae).

PubMed

Lustgraaf, B V D

1978-01-01

At. 75 and 80% relative humidity (RH), on a wheat germ flake medium, Aspergillus penicilloides grew abundantly and suppressed the population growth of Dermatophagoides pteronyssiunus. At 71% RH, A. penicilloides grew moderately and was only antagonistic to D. pteronyssinus when the fungus was previously incubated on the medium.On a human dander medium and on mattress dust, A. penicilloides grew moderately at 71% and 75% RH and stimulated the development of D. pteronyssinus populations. Also a moderate growth of Eurotium repens on human dander positively influenced D. pteronyssinus. Wallemia sebi and Penicillium brevicompactum grew slightly or did not grow at all at 75% RH. No effect was observed on D. pteronyssinus.It appears that xerophilic fungi may stimulate, and occasionally may reduce, the growth of house-dust mite populations in the natural environment.

Molecular, Structural and Immunological Characterization of Der p 18, a Chitinase-Like House Dust Mite Allergen.

PubMed

Resch, Yvonne; Blatt, Katharina; Malkus, Ursula; Fercher, Christian; Swoboda, Ines; Focke-Tejkl, Margit; Chen, Kuan-Wei; Seiberler, Susanne; Mittermann, Irene; Lupinek, Christian; Rodriguez-Dominguez, Azahara; Zieglmayer, Petra; Zieglmayer, René; Keller, Walter; Krzyzanek, Vladislav; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

2016-01-01

The house dust mite (HDM) allergen Der p 18 belongs to the glycoside hydrolase family 18 chitinases. The relevance of Der p 18 for house dust mite allergic patients has only been partly investigated. To perform a detailed characterization of Der p 18 on a molecular, structural and immunological level. Der p 18 was expressed in E. coli, purified to homogeneity, tested for chitin-binding activity and its secondary structure was analyzed by circular dichroism. Der p 18-specific IgG antibodies were produced in rabbits to localize the allergen in mites using immunogold electron microscopy and to search for cross-reactive allergens in other allergen sources (i.e. mites, crustacea, mollusca and insects). IgE reactivity of rDer p 18 was tested with sera from clinically well characterized HDM-allergic patients (n = 98) and its allergenic activity was analyzed in basophil activation experiments. Recombinant Der p 18 was expressed and purified as a folded, biologically active protein. It shows weak chitin-binding activity and partial cross-reactivity with Der f 18 from D. farinae but not with proteins from the other tested allergen sources. The allergen was mainly localized in the peritrophic matrix of the HDM gut and to a lower extent in fecal pellets. Der p 18 reacted with IgE from 10% of mite allergic patients from Austria and showed allergenic activity when tested for basophil activation in Der p 18-sensitized patients. Der p 18 is a rather genus-specific minor allergen with weak chitin-binding activity but exhibits allergenic activity and therefore should be included in diagnostic test panels for HDM allergy.

Molecular, Structural and Immunological Characterization of Der p 18, a Chitinase-Like House Dust Mite Allergen

PubMed Central

Resch, Yvonne; Blatt, Katharina; Malkus, Ursula; Fercher, Christian; Swoboda, Ines; Focke-Tejkl, Margit; Chen, Kuan-Wei; Seiberler, Susanne; Mittermann, Irene; Lupinek, Christian; Rodriguez-Dominguez, Azahara; Zieglmayer, Petra; Zieglmayer, René; Keller, Walter; Krzyzanek, Vladislav; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

2016-01-01

Background The house dust mite (HDM) allergen Der p 18 belongs to the glycoside hydrolase family 18 chitinases. The relevance of Der p 18 for house dust mite allergic patients has only been partly investigated. Objective To perform a detailed characterization of Der p 18 on a molecular, structural and immunological level. Methods Der p 18 was expressed in E. coli, purified to homogeneity, tested for chitin-binding activity and its secondary structure was analyzed by circular dichroism. Der p 18-specific IgG antibodies were produced in rabbits to localize the allergen in mites using immunogold electron microscopy and to search for cross-reactive allergens in other allergen sources (i.e. mites, crustacea, mollusca and insects). IgE reactivity of rDer p 18 was tested with sera from clinically well characterized HDM-allergic patients (n = 98) and its allergenic activity was analyzed in basophil activation experiments. Results Recombinant Der p 18 was expressed and purified as a folded, biologically active protein. It shows weak chitin-binding activity and partial cross-reactivity with Der f 18 from D. farinae but not with proteins from the other tested allergen sources. The allergen was mainly localized in the peritrophic matrix of the HDM gut and to a lower extent in fecal pellets. Der p 18 reacted with IgE from 10% of mite allergic patients from Austria and showed allergenic activity when tested for basophil activation in Der p 18-sensitized patients. Conclusion Der p 18 is a rather genus-specific minor allergen with weak chitin-binding activity but exhibits allergenic activity and therefore should be included in diagnostic test panels for HDM allergy. PMID:27548813

Molecular Determinants for Antibody Binding on Group 1 House Dust Mite Allergens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chruszcz, Maksymilian; Pomés, Anna; Glesner, Jill

2012-07-11

House dust mites produce potent allergens, Der p 1 and Der f 1, that cause allergic sensitization and asthma. Der p 1 and Der f 1 are cysteine proteases that elicit IgE responses in 80% of mite-allergic subjects and have proinflammatory properties. Their antigenic structure is unknown. Here, we present crystal structures of natural Der p 1 and Der f 1 in complex with a monoclonal antibody, 4C1, which binds to a unique cross-reactive epitope on both allergens associated with IgE recognition. The 4C1 epitope is formed by almost identical amino acid sequences and contact residues. Mutations of the contactmore » residues abrogate mAb 4C1 binding and reduce IgE antibody binding. These surface-exposed residues are molecular targets that can be exploited for development of recombinant allergen vaccines.« less

Repeated measurements of mite and pet allergen levels in house dust over a time period of 8 years.

PubMed

Antens, C J M; Oldenwening, M; Wolse, A; Gehring, U; Smit, H A; Aalberse, R C; Kerkhof, M; Gerritsen, J; de Jongste, J C; Brunekreef, B

2006-12-01

Studies of the association between indoor allergen exposure and the development of allergic diseases have often measured allergen exposure at one point in time. We investigated the variability of house dust mite (Der p 1, Der f 1) and cat (Fel d 1) allergen in Dutch homes over a period of 8 years. Data were obtained in the Dutch PIAMA birth cohort study. Dust from the child's mattress, the parents' mattress and the living room floor was collected at four points in time, when the child was 3 months, 4, 6 and 8 years old. Dust samples were analysed for Der p 1, Der f 1 and Fel d 1 by sandwich enzyme immuno assay. Mite allergen concentrations for the child's mattress, the parents' mattress and the living room floor were moderately correlated between time-points. Agreement was better for cat allergen. For Der p 1 and Der f 1 on the child's mattress, the within-home variance was close to or smaller than the between-home variance in most cases. For Fel d 1, the within-home variance was almost always smaller than the between-home variance. Results were similar for allergen levels expressed per gram of dust and allergen levels expressed per square metre of the sampled surface. Variance ratios were smaller when samples were taken at shorter time intervals than at longer time intervals. Over a period of 4 years, mite and cat allergens measured in house dust are sufficiently stable to use single measurements with confidence in epidemiological studies. The within-home variance was larger when samples were taken 8 years apart so that over such long periods, repetition of sampling is recommended.

Acaricidal activity of Cymbopogon citratus and Azadirachta indica against house dust mites.

PubMed

Hanifah, Azima Laili; Awang, Siti Hazar; Ming, Ho Tze; Abidin, Suhaili Zainal; Omar, Maizatul Hashima

2011-10-01

To examine the acaricidal effects of the essential oil of Cymbopogon citratus leaf extract (lemongrass) and ethanolic Azadirachta indica leaf extract (neem) against house dust mites Dermatophagoides farinae (D. farinae) and Dermatophagoides pteronyssinus (D. pteronyssinus). Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations (50.00%, 25.00%, 12.50%, 6.25% and 3.13%) and exposure times (24hrs, 48hrs, 72hrs and 96 hrs). All treatments were replicated 7 times, and the experiment repeated once. The topical and contact activities of the two herbs were investigated. Mortalities from lemongrass extract were higher than neem for both topical and contact activities. At 50 % concentration, both 24 hrs topical and contact exposures to lemongrass resulted in more than 91% mortalities for both species of mites. At the same concentration and exposure time, neem resulted in topical mortalities of 40.3% and 15.7% against D. pteronyssinus and D. farinae respectively; contact mortalities were 8.0% and 8.9% against the 2 mites, respectively. There was no difference in topical mortalities of D. pteronyssinus from exposure to concentrations of lemongrass and neem up to 12.50%; lemongrass was more effective than neem at the higher concentrations. Generally, topical mortalities of D. farinae due to lemongrass are higher than that due to neem. Contact mortalities of lemongrass are always higher that neem against both species of mites.

Acaricidal activity of Cymbopogon citratus and Azadirachta indica against house dust mites

PubMed Central

Hanifah, Azima Laili; Awang, Siti Hazar; Ming, Ho Tze; Abidin, Suhaili Zainal; Omar, Maizatul Hashima

2011-01-01

Objective To examine the acaricidal effects of the essential oil of Cymbopogon citratus leaf extract (lemongrass) and ethanolic Azadirachta indica leaf extract (neem) against house dust mites Dermatophagoides farinae (D. farinae) and Dermatophagoides pteronyssinus (D. pteronyssinus). Methods Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations (50.00%, 25.00%, 12.50%, 6.25% and 3.13%) and exposure times (24hrs, 48hrs, 72hrs and 96 hrs). All treatments were replicated 7 times, and the experiment repeated once. The topical and contact activities of the two herbs were investigated. Results Mortalities from lemongrass extract were higher than neem for both topical and contact activities. At 50 % concentration, both 24 hrs topical and contact exposures to lemongrass resulted in more than 91% mortalities for both species of mites. At the same concentration and exposure time, neem resulted in topical mortalities of 40.3% and 15.7% against D. pteronyssinus and D. farinae respectively; contact mortalities were 8.0% and 8.9% against the 2 mites, respectively. There was no difference in topical mortalities of D. pteronyssinus from exposure to concentrations of lemongrass and neem up to 12.50%; lemongrass was more effective than neem at the higher concentrations. Conclusions Generally, topical mortalities of D. farinae due to lemongrass are higher than that due to neem. Contact mortalities of lemongrass are always higher that neem against both species of mites. PMID:23569794

Comparison of the Allergic Responses Induced by PeniciIlium chrysogenum and House Dust Mite Extracts in a Mouse Model

EPA Science Inventory

A report by the Institute of Medicine suggested that more research is needed to better understand mold effects on allergic disease, particularly asthma development. We compared the ability of the fungal Penicillium chrysogenum (PCE) and house dust mite (HDM) extracts to induce al...

Prevalence of house dust mites and dermatophagoides group 1 antigens collected from bedding, skin and hair coat of dogs in south-west England.

PubMed

Jackson, Anna P; Foster, Aiden P; Hart, Barbara J; Helps, Chris R; Shaw, Susan E

2005-02-01

The house dust mites Dermatophagoides farinae (Df) and D. pteronyssinus (Dpt) are commonly implicated as allergens causing canine atopic dermatitis in the UK. However, there are few studies that characterize the exposure of UK pet dogs to these mites. The objectives of this study were to determine the prevalence of the mite species on the skin, hair coat and bedding of a population of pet dogs. Dust samples (n = 68) were collected from both dogs and their beds using a standardized vacuuming technique and stored at -20 degrees C. Mites were identified using accepted morphological criteria. House dust mite allergen concentrations were assayed using standardized ELISA for Dpt and Df group 1 allergens (Der p 1 and Der f 1). Mites were identified in 15/68 samples (22%) and Dpt was the most common. Df mites were not present. Der p 1 allergens were detected in 60% of samples, and Der f 1 in 6% of samples. There were no significant differences between the number of Der p 1 positive samples from dogs and the number of those from their bedding, or between the average Der p 1 concentrations from dogs and the number of those from their bedding. Contrary to studies elsewhere in Europe and the USA, these findings support studies of human asthma patients in the UK, where exposure to Df is rare, but to Dpt is common. As the prevalence of positive intradermal and serological reactions to Df in atopic dogs is high, further investigations are warranted to clarify true Df hypersensitivity or potential immunological cross-reactivity between mite allergens.

Different sensitization to storage mites depending on the co-exposure to house dust mites.

PubMed

Morales, María; Iraola, Victor; Leonor, José Ramón; Bartra, Joan; Rodríguez, Fernando; Boquete, Manuel; Huertas, Ángel Julio; Paniagua, María Josefa; Pinto, Helder; Carnés, Jerónimo

2015-01-01

Co-sensitization to house dust mites (HDMs) and storage mites (SMs) is very frequent, although the clinical relevance is not well established. To describe the pattern of sensitization and immunologic characterization of patients with positive skin prick test reactions to HDMs and SMs in 4 areas of Spain, selected according to high exposure to HDMs and variable exposure to SMs. One hundred sixty-nine individuals with positive skin prick test reactions to HDMs and SMs were included. Specific IgE levels to different mite species and to Der p 1, Der p 2, and Der p 10 were determined. Immunoblots to Dermatophagoides pteronyssinus, Lepidoglyphus destructor, and Tyrophagus putrescentiae extracts were carried out, and allergograms were obtained. Results of different areas were compared. A high rate of polysensitization to SMs was observed, although 12% of participants did not have specific IgE to any SM species. Sensitization to Dermatophagoides species, Der p 2, and L destructor were predominant, although significant differences were observed among areas depending on the grade of exposure to SMs. In areas with high exposure, the SM allergogram showed greater recognition of group 2 allergen. Sensitization patterns to SMs in patients sensitized to HDMs and SMs differ depending on the exposure to SMs. Sensitization, mainly to L destructor, seems to exist in areas with high exposure, possibly with group 2 allergens mainly involved. However, in areas with low SM populations, sensitizations observed by skin prick testing appear to be related to HDM exposure. Copyright © 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Effects of microwave radiation on house dust mites, Dermatophagoides pteronyssinus and Dermatophagoides farinae (Astigmata: Pyroglyphidae).

PubMed

Ernieenor, F C L; Ho, T M

2010-11-01

Dermatophagoides pteronyssinus and Dermatophagoides farinae mites are commonly found in house dust, and are important sources of allergens affecting humans. Various approaches to killing the mites have been examined. This study investigated the mortalities of adult mites exposed to 2,450 MHz microwave radiation produced by 3 ovens at various exposure times and power settings. The ovens all had 3 power settings. The average maximum water temperatures generated at high, medium and low power settings were 99.4 +/- 0.2, 84.1 +/- 0.4 and 44.8 +/- 0.9 degrees C, respectively. At high and medium settings, there was 100.0% mortality in both species when exposed for 300 seconds. The mean mortality rates at low power were 10.8 +/- 0.7% for D. pteronyssinus and 9.7 +/- 2.6% for D. farinae. When mites were exposed in the presence of culture media, the mortality rates decreased with increasing weight of media. The mean mortality with the largest amount of media tested at high power setting was 61.4%.

A 12-week DBPC dose-finding study with sublingual monomeric allergoid tablets in house dust mite-allergic patients.

PubMed

Hüser, C; Dieterich, P; Singh, J; Shah-Hosseini, K; Allekotte, S; Lehmacher, W; Compalati, E; Mösges, R

2017-01-01

In sublingual immunotherapy, optimal doses are a key factor for therapeutic outcomes. The aim of this study with tablets containing carbamylated monomeric house dust mite allergoids was to determine the most effective and safe dose. In this double-blind, placebo-controlled dose-finding study, 131 patients with house dust mite-induced allergic rhinoconjunctivitis were randomized to 12-week treatments with 300 UA/day, 1000 UA/day, 2000 UA/day, 3000 UA/day or placebo. Conjunctival provocation tests (CPT) were performed before, during and after treatment. The change in mean allergic severity (primary endpoint), calculated from the severity of the CPT reaction, and the proportion of patients with an improved CPT threshold (secondary endpoint) determined the treatment effect. The mean allergic severity decreased in all groups, including the placebo group. It was lower in all active treatment groups (300 UA/day: 0.14, 1000 UA/day: 0.15, 2000 UA/day: 0.10, 3000 UA/day: 0.15) than in the placebo group (0.30). However, this difference was not statistically significant (P < 0.1). The percentage of patients with an improved CPT threshold was higher in the active treatment groups (300 UA/day: 73.9%; 1000 UA/day: 76.0%; 2000 UA/day: 88.5%; 3000 UA/day: 76.0%) than in the placebo group (64.3%). The difference between placebo and 2000 UA/day was statistically significant (P = 0.04). In 13 (10%) exposed patients, a total of 20 treatment-related adverse events of mild severity were observed. The 12-week daily treatment using 2000 UA/day monomeric allergoid sublingual tablets is well tolerated and reduces the CPT reaction in house dust mite-allergic patients. © 2016 The Authors. Allergy Published by John Wiley & Sons Ltd.

House-dust mite allergy: mapping of Dermatophagoides pteronyssinus allergens for dogs by two-dimensional immunoblotting.

PubMed

Martins, Luís Miguel Lourenço; Marques, Andreia Grilo; Pereira, Luísa Maria Dotti Silva; Goicoa, Ana; Semião-Santos, Saul José; Bento, Ofélia Pereira

2015-04-01

Specific immunotherapy has shown to be very useful for allergy control in dogs, with a common success rate ranging from 65% to 70%. However, this efficacy could probably be improved and the identification of individual allergomes, with the choice of more adequate molecular allergen pools for specific immunotherapy, being the strategy. To map Dermatophagoides pteronyssinus (Der p) allergens for mite-sensitized atopic dogs, for better understanding how individual allergograms may influence the response to house-dust mite immunotherapy. To identify the Der p mite allergome for dogs, 20 individuals allergic to dust-mites and sensitized to Der p, were selected. The extract from Der p was submitted to isoelectric focusing (IEF), one-dimensional (1-D) and two-dimensional (2-D) sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Separated proteins were blotted onto polyvinylidene difluoride (PVDF) membranes and immunoblottings were performed with patient sera. Allergen-bound specific IgE was detected. Eleven allergens were identified from isoelectric focusing (IEF), as well as from 1-D SDS PAGE. From 2-D SDS-PAGE, 24 spots were identified. Several similarities were found between dog and human allergograms and no absolute correlation between sensitization and allergy was observed either. As in humans, different individual allergograms do not seem to implicate different clinical patterns, but may influence the response to specific immunotherapy. The molecular epidemiology approach in veterinary allergy management, by the characterization of individual patients' allergoms and by choosing the best molecular allergen pool for each patient could also improve the efficacy of allergy immunotherapy.

Inert dusts and their effects on the poultry red mite (Dermanyssus gallinae).

PubMed

Kilpinen, Ole; Steenberg, Tove

2009-06-01

The haematophagous poultry red mite (Dermanyssus gallinae) is the most important pest of egg laying hens in many parts of the world. Control has often relied on chemical pesticides, but inert dusts, which are thought to kill target hosts primarily by desiccation, have become one of the most commonly applied alternative control methods for poultry red mite in Europe. This development has occurred despite a lack of knowledge of the efficacy of the different types of inert dusts and how this is affected by environmental parameters, e.g. the high relative humidity found in poultry houses. In this laboratory study the efficacy of different commercial inert dust products against D. gallinae is compared. All tested compounds killed mites, but there was a clear ranking of efficacy (measured as weight loss after 24 h and as time until 50% mortality), particularly at 75% relative humidity (RH). At 85% RH the efficacy was significantly lower for all tested compounds (P < 0.001). Weight changes over time followed an exponential evaporation model until the mites started dying whereafter the rate of evaporation increased again and followed a slightly different exponential evaporation model. A tarsal test showed that 24 h exposure to surfaces treated with doses much lower than those recommended by the producers is sufficient to kill mites as fast as when they were dusted with massive doses. These data emphasise the need for thorough treatment of all surfaces in a poultry house in order to combat D. gallinae.

Feather bedding and childhood asthma associated with house dust mite sensitisation: a randomised controlled trial.

PubMed

Glasgow, Nicholas J; Ponsonby, Anne-Louise; Kemp, Andrew; Tovey, Euan; van Asperen, Peter; McKay, Karen; Forbes, Samantha

2011-06-01

Observational studies report inverse associations between the use of feather upper bedding (pillow and/or quilt) and asthma symptoms but there is no randomised controlled trial (RCT) evidence assessing the role of feather upper bedding as a secondary prevention measure. To determine whether, among children not using feather upper bedding, a new feather pillow and feather quilt reduces asthma severity among house dust mite (HDM) sensitised children with asthma over a 1-year period compared with standard dust mite avoidance advice, and giving children a new mite-occlusive mattress cover. RCT. The Calvary Hospital in the Australian Capital Territory and the Children's Hospital at Westmead, Sydney, New South Wales. 197 children with HDM sensitisation and moderate to severe asthma. Intervention New upper bedding duck feather pillow and quilt and a mite-occlusive mattress cover (feather) versus standard care and a mite-occlusive mattress cover (standard). The proportion of children reporting four or more episodes of wheeze in the past year; an episode of speech-limiting wheeze; or one or more episodes of sleep disturbance caused by wheezing; and spirometry with challenge testing. Statistical analysis included multiple logistic and linear regression. No differences between groups were found for primary end points--frequent wheeze (OR 1.51, 95% CI 0.83 to 2.76, p=0.17), speech-limiting wheeze (OR 0.70, 95% CI 0.32 to 1.48, p=0.35), sleep disturbed because of wheezing (OR 1.17, 95% CI 0.64 to 2.13, p=0.61) or for any secondary end points. Secondary analyses indicated the intervention reduced the risk of sleep being disturbed because of wheezing and severe wheeze to a greater extent for children who slept supine. No differences in respiratory symptoms or lung function were observed 1 year after children with moderate-severe asthma and HDM sensitisation were given a mite-occlusive mattress cover and then received either feather upper bedding (pillow and quilt) or standard

Feather bedding and childhood asthma associated with house dust mite sensitisation: a randomised controlled trial

PubMed Central

Glasgow, Nicholas J; Ponsonby, Anne-Louise; Kemp, Andrew; Tovey, Euan; van Asperen, Peter; McKay, Karen; Forbes, Samantha

2011-01-01

Introduction Observational studies report inverse associations between the use of feather upper bedding (pillow and/or quilt) and asthma symptoms but there is no randomised controlled trial (RCT) evidence assessing the role of feather upper bedding as a secondary prevention measure. Objective To determine whether, among children not using feather upper bedding, a new feather pillow and feather quilt reduces asthma severity among house dust mite (HDM) sensitised children with asthma over a 1-year period compared with standard dust mite avoidance advice, and giving children a new mite-occlusive mattress cover. Design RCT. Setting The Calvary Hospital in the Australian Capital Territory and the Children's Hospital at Westmead, Sydney, New South Wales. Patients 197 children with HDM sensitisation and moderate to severe asthma. Intervention New upper bedding duck feather pillow and quilt and a mite-occlusive mattress cover (feather) versus standard care and a mite-occlusive mattress cover (standard). Main outcome measures The proportion of children reporting four or more episodes of wheeze in the past year; an episode of speech-limiting wheeze; or one or more episodes of sleep disturbance caused by wheezing; and spirometry with challenge testing. Statistical analysis included multiple logistic and linear regression. Results No differences between groups were found for primary end points – frequent wheeze (OR 1.51, 95% CI 0.83 to 2.76, p=0.17), speech-limiting wheeze (OR 0.70, 95% CI 0.32 to 1.48, p=0.35), sleep disturbed because of wheezing (OR 1.17, 95% CI 0.64 to 2.13, p=0.61) or for any secondary end points. Secondary analyses indicated the intervention reduced the risk of sleep being disturbed because of wheezing and severe wheeze to a greater extent for children who slept supine. Conclusion No differences in respiratory symptoms or lung function were observed 1 year after children with moderate–severe asthma and HDM sensitisation were given a mite

Evidence of the efficacy and safety of house dust mite subcutaneous immunotherapy in elderly allergic rhinitis patients: a randomized, double-blind placebo-controlled trial.

PubMed

Bożek, Andrzej; Kołodziejczyk, Krzysztof; Kozłowska, Renata; Canonica, Giorgio Walter

2017-01-01

Allergen specific immunotherapy (AIT) in elderly patients is controversial, and there is still little evidence supporting the safety and efficacy of this treatment in this population. The study objective was to evaluate the safety and efficacy of AIT for house dust mite allergens in patients over 65 years of age with allergic rhinitis (AR) and a documented allergy to house dust mites. The primary endpoint was the change from baseline in the mean average adjusted symptom score (AAdSS) and the total combined rhinitis score (TCRS) difference in the least square means for the label compared to placebo. Fifty-eight AR elderly patients who were monosensitized to house dust mites were individually randomized in comparable numbers to one of two parallel groups with the following interventions: 2 years of perennial AIT using PURETHAL Mites or placebo. The symptoms and medication scores were presented as the AAdSS and TCRS. Quality of life, based on the rhinoconjunctivitis quality of life questionnaire (RQLQ), nasal allergen provocation responsiveness, serum allergen-specific IgG4 to D. pteronyssinus and D. farinae and Der p1 and Der p2 were monitored. The intent-to-treat population was analysed. After 24 months of AIT, AAdSS significantly decreased from 4.27 ± 1.58 to 1.82 ± 0.71 ( p  < 0.05). The TCRS was significantly decreased after 2 years of AIT. Serum-specific IgG4 against D. pteronyssinus , D. farinae, Der p1 , and Der p2 increased during the AIT trial in the study group. The RQLQ score was significantly improved in patients who received AIT, from 1.86 (95% CI 1.51-1.78) to 1.26 (95% CI 1.09-1.55). Two mild systemic anaphylactic reactions (degree I) were reported after injections in the active group during the AIT therapy. The DBPC trial showed AIT for house dust mite allergens was effective and safe in elderly patients with allergic rhinitis. This randomized, double-blinded placebo-controlled (DBPC) trial was conducted at one centre (Clinical

Placebo-controlled study of the mite allergen-reducing effect of tannic acid plus benzyl benzoate on carpets in homes of children with house dust mite sensitization and asthma.

PubMed

Lau, Susanne; Wahn, Julia; Schulz, Gabriele; Sommerfeld, Christine; Wahn, Ulrich

2002-02-01

We studied the effect of a spray containing 1% benzyl benzoate, an acaricide, and 1% tannic acid ('Lowal'; a protein-denaturing substance), on concentrations of major allergens from house dust mite (HDM) species Dermatophagoides pteronyssinus and D. farinae (Der p 1 and Der f 1, respectively) in carpets. In a double-blind, placebo-controlled study with crossover design, 30 homes of children with HDM sensitization and asthma were included. All houses showed > or = 400 ng/g of Der p 1 + Der f 1 in carpet dust. The first treatment was performed on day 0 (group 1 active treatment, n = 15; group 2 placebo treatment, n = 15). After 2 and 8 weeks, dust samples were collected for quantification of mite allergens. After a 2-week washout period, the second treatment was performed (group 1 placebo treatment; group 2 active treatment). Again, carpet dust was collected after 2 and 8 weeks. Twenty-two of 30 families completed the trial: 14/15 in group 1 and eight of 15 in group 2. On day 0, there was no significant difference in mite allergen exposure between group 1 and group 2 (1,498 vs. 2,239 ng/g of Der p 1 + Der f 1, respectively). In group 1, the geometric mean for the difference of mite allergen concentration comparing day 0 and week 6 was 196 ng/g (95% CI: -7,161 and 8,401) for the first treatment (active) and 15 ng/g (95% CI: -1,079 and 1,292) for the second treatment (control). In group 2, the difference was 66 ng/g (95% CI: -398 and 1,515) for the first treatment (control) and 609 ng/g (95% CI: 186 and 9,264) for the second treatment (active). Comparing placebo and active treatment in total, there was a significant decrease following placebo treatment after 14 days (p = 0.026). After 8 weeks, active treatment was superior to placebo treatment (p = 0.049), but the allergen reduction achieved was < 20% (median 1,500 ng/g on day 0 vs. 1,250 ng/g after 8 weeks). We conclude that the slight mite allergen reduction on carpets achieved by the treatment with 'Lowal' is

Time-dependent distinct roles of Toll-like receptor 4 in a house dust mite-induced asthma mouse model.

PubMed

Ishii, T; Niikura, Y; Kurata, K; Muroi, M; Tanamoto, K; Nagase, T; Sakaguchi, M; Yamashita, N

2018-03-01

House dust mites (HDMs) are a common source of allergens that trigger both allergen-specific and innate immune responses in humans. Here, we examined the effect of allergen concentration and the involvement of Toll-like receptor 4 (TLR4) in the process of sensitization to house dust mite allergens in an HDM extract-induced asthma mouse model.　Intranasal administration of HDM extract induced an immunoglobulin E response and eosinophilic inflammation in a dose-dependent manner from 2.5 to 30 μg/dose. In TLR4-knockout mice, the infiltration of eosinophils and neutrophils into the lung was decreased compared with that in wild-type mice in the early phase of inflammation (total of three doses). However, in the late phase of inflammation (total of seven doses), eosinophil infiltration was significantly greater in TLR4-knockout mice than in wild-type mice. This suggests that the roles of TLR4 signaling are different between the early phase and the later phase of HDM allergen-induced inflammation. Thus, innate immune response through TLR4 regulated the response to HDM allergens, and the regulation was altered during the phase of inflammation. © 2018 The Foundation for the Scandinavian Journal of Immunology.

Comparison of the skin-prick test and Phadia ImmunoCAP as tools to diagnose house-dust mite allergy.

PubMed

Jung, Yong Gi; Cho, Hyun-Jin; Park, Ga Young; Min, Jin-Young; Kim, Hyo Yeol; Dhong, Hun-Jong; Chung, Seung Kyu; Kim, Seon Woo

2010-01-01

When the skin-prick test (SPT) and in vitro test such as ImmunoCAP assay are performed simultaneously, results do not always coincide in some patients. Our objectives, therefore, were (1) to assess differences in allergic test results according to age group and (2) to establish appropriate guidelines for diagnosing mite allergy according to age. A total of 692 participants complaining of allergic rhinitis symptoms participated. Patients were divided according to age; the mean age was 32 years (range, 8-76 years). The SPT and ImmunoCAP assays were performed to detect allergies to house-dust mites (Dermatophagoides pteronyssinus and Dermatophagoides farinae). The association between age and the result of each allergy test were examined, and a cutoff age for proper application of each test was than estimated. Three hundred thirty-six patients (48.6%) were allergic to D. pteronyssinus and 350 patients (50.6%) were allergic to D. farinae. In the case of D. pteronyssinus, SPT was proved to be more useful in detecting allergy for subjects <50 years old (p < 0.0001). However in case of D. farinae, ImmunoCAP was useful for all age groups, but SPT showed decreased ratio of positive result for subjects >30 years old (p < 0.0001). This study was the first to compare results of allergy tests according to age using true allergens. For patients >50 years of age, the ImmunoCAP was found to be the preferred method for detecting allergy to house-dust mites and for patients <30 years old, SPT is the recommended first choice.

Reducing risk of house dust mite and cockroach allergen exposure in inner-city children with asthma.

PubMed

Kuster, P A

1996-01-01

Asthma prevalence among disadvantaged and minority children is disproportionately higher in inner-city populations. Environmental allergen exposure, particularly that of house dust mites and cockroaches, is known to contribute to asthma exacerbations in children. Environmental control of these particular triggers is a necessary component of asthma education and should be incorporated into the teaching plan for these children. The costs surrounding environmental control may not be within the means of many families living in urban, inner-city environments; therefore nurses should offer families creative ideas and cost effective suggestions for controlling environmental triggers.

Asthma, Airway Symptoms and Rhinitis in Office Workers in Malaysia: Associations with House Dust Mite (HDM) Allergy, Cat Allergy and Levels of House Dust Mite Allergens in Office Dust.

PubMed

Lim, Fang Lee; Hashim, Zailina; Than, Leslie Thian Lung; Md Said, Salmiah; Hisham Hashim, Jamal; Norbäck, Dan

2015-01-01

A prevalence study was conducted among office workers in Malaysia (N= 695). The aim of this study was to examine associations between asthma, airway symptoms, rhinitis and house dust mites (HDM) and cat allergy and HDM levels in office dust. Medical data was collected by a questionnaire. Skin prick tests were performed for HDM allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae) and cat allergen Felis domesticus. Indoor temperature and relative air humidity (RH) were measured in the offices and vacuumed dust samples were analyzed for HDM allergens. The prevalence of D. pteronyssinus, D. farinae and cat allergy were 50.3%, 49.0% and 25.5% respectively. Totally 9.6% had doctor-diagnosed asthma, 15.5% had current wheeze and 53.0% had current rhinitis. The Der p 1 (from D. pteronyssinus) and Der f 1 (from D. farinae) allergens levels in dust were 556 ng/g and 658 ng/g respectively. Statistical analysis was conducted by multilevel logistic regression, adjusting for age, gender, current smoking, HDM or cat allergy, home dampness and recent indoor painting at home. Office workers with HDM allergy had more wheeze (p= 0.035), any airway symptoms (p= 0.032), doctor-diagnosed asthma (p= 0.005), current asthma (p= 0.007), current rhinitis (p= 0.021) and rhinoconjuctivitis (p< 0.001). Cat allergy was associated with wheeze (p= 0.021), wheeze when not having a cold (p= 0.033), any airway symptoms (p= 0.034), doctor-diagnosed asthma (p= 0.010), current asthma (p= 0.020) and nasal allergy medication (p= 0.042). Der f 1 level in dust was associated with daytime breathlessness (p= 0.033) especially among those with HDM allergy. Der f 1 levels were correlated with indoor temperature (p< 0.001) and inversely correlated with RH (p< 0.001). In conclusion, HDM and cat allergies were common and independently associated with asthma, airway symptoms and rhinitis. Der f 1 allergen can be a risk factor for daytime breathlessness.

Asthma, Airway Symptoms and Rhinitis in Office Workers in Malaysia: Associations with House Dust Mite (HDM) Allergy, Cat Allergy and Levels of House Dust Mite Allergens in Office Dust

PubMed Central

Lim, Fang Lee; Hashim, Zailina; Than, Leslie Thian Lung; Md Said, Salmiah; Hisham Hashim, Jamal; Norbäck, Dan

2015-01-01

A prevalence study was conducted among office workers in Malaysia (N= 695). The aim of this study was to examine associations between asthma, airway symptoms, rhinitis and house dust mites (HDM) and cat allergy and HDM levels in office dust. Medical data was collected by a questionnaire. Skin prick tests were performed for HDM allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae) and cat allergen Felis domesticus. Indoor temperature and relative air humidity (RH) were measured in the offices and vacuumed dust samples were analyzed for HDM allergens. The prevalence of D. pteronyssinus, D. farinae and cat allergy were 50.3%, 49.0% and 25.5% respectively. Totally 9.6% had doctor-diagnosed asthma, 15.5% had current wheeze and 53.0% had current rhinitis. The Der p 1 (from D. pteronyssinus) and Der f 1 (from D. farinae) allergens levels in dust were 556 ng/g and 658 ng/g respectively. Statistical analysis was conducted by multilevel logistic regression, adjusting for age, gender, current smoking, HDM or cat allergy, home dampness and recent indoor painting at home. Office workers with HDM allergy had more wheeze (p= 0.035), any airway symptoms (p= 0.032), doctor-diagnosed asthma (p= 0.005), current asthma (p= 0.007), current rhinitis (p= 0.021) and rhinoconjuctivitis (p< 0.001). Cat allergy was associated with wheeze (p= 0.021), wheeze when not having a cold (p= 0.033), any airway symptoms (p= 0.034), doctor-diagnosed asthma (p= 0.010), current asthma (p= 0.020) and nasal allergy medication (p= 0.042). Der f 1 level in dust was associated with daytime breathlessness (p= 0.033) especially among those with HDM allergy. Der f 1 levels were correlated with indoor temperature (p< 0.001) and inversely correlated with RH (p< 0.001). In conclusion, HDM and cat allergies were common and independently associated with asthma, airway symptoms and rhinitis. Der f 1 allergen can be a risk factor for daytime breathlessness. PMID:25923543

Air-conditioner filters enriching dust mites allergen.

PubMed

Zhan, Xiaodong; Li, Chaopin; Xu, Haifeng; Xu, Pengfei; Zhu, Haibin; Diao, Jidong; Li, Na; Zhao, Beibei

2015-01-01

We detected the concentration of dust mites allergen (Der f1 & Der p1) in the air of different places before and after the starting of air-conditioners in Wuhu City, Anhui, China, and to discuss the relation between the dust mites allergen in air-conditioner filters and the asthma attack. The dust samples were collected from the air-conditioner filters in dining rooms, shopping malls, hotels and households respectively. Concentrations of dust mites major group allergen 1 (Der f 1, Der p1) were detected with enzyme linked immunosorbent assay (ELISA), and the dust mite immune activities were determined by dot-ELISA. The concentration of Der f1 in dining rooms, shopping malls, hotels and households was 1.52 μg/g, 1.24 μg/g, 1.31 μg/g and 1.46 μg/g respectively, and the concentration of Der p1 in above-mentioned places was 1.23 μg/g, 1.12 μg/g, 1.16 μg/g and 1.18 μg/g respectively. The concentration of Der f1 & Der p1 in air was higher after the air-conditioners starting one hours later, and the difference was significant (P<0.05, respectively). Additionally, dot-ELISA findings revealed that the allergen extracted from the dust was capable of reacting with IgE from the sera of asthma mice allergic to dust mites. The study concludes that air-conditioner filters can enrich dust mites major group allergen, and the allergens can induce asthma. The air-conditioner filters shall be cleaned or replaced regularly to prevent or reduce accumulation of the dust mites and its allergens.

Air-conditioner filters enriching dust mites allergen

PubMed Central

Zhan, Xiaodong; Li, Chaopin; Xu, Haifeng; Xu, Pengfei; Zhu, Haibin; Diao, Jidong; Li, Na; Zhao, Beibei

2015-01-01

We detected the concentration of dust mites allergen (Der f1 & Der p1) in the air of different places before and after the starting of air-conditioners in Wuhu City, Anhui, China, and to discuss the relation between the dust mites allergen in air-conditioner filters and the asthma attack. The dust samples were collected from the air-conditioner filters in dining rooms, shopping malls, hotels and households respectively. Concentrations of dust mites major group allergen 1 (Der f 1, Der p1) were detected with enzyme linked immunosorbent assay (ELISA), and the dust mite immune activities were determined by dot-ELISA. The concentration of Der f1 in dining rooms, shopping malls, hotels and households was 1.52 μg/g, 1.24 μg/g, 1.31 μg/g and 1.46 μg/g respectively, and the concentration of Der p1 in above-mentioned places was 1.23 μg/g, 1.12 μg/g, 1.16 μg/g and 1.18 μg/g respectively. The concentration of Der f1 & Der p1 in air was higher after the air-conditioners starting one hours later, and the difference was significant (P<0.05, respectively). Additionally, dot-ELISA findings revealed that the allergen extracted from the dust was capable of reacting with IgE from the sera of asthma mice allergic to dust mites. The study concludes that air-conditioner filters can enrich dust mites major group allergen, and the allergens can induce asthma. The air-conditioner filters shall be cleaned or replaced regularly to prevent or reduce accumulation of the dust mites and its allergens. PMID:26064381

Attempting to control mite allergens with mechanical ventilation and dehumidification in British houses.

PubMed

Niven, R; Fletcher, A M; Pickering, A C; Custovic, A; Sivour, J B; Preece, A R; Oldham, L A; Francis, H C

1999-05-01

Allergen avoidance is of considerable interest in the treatment and even prevention of asthma. Attempts to control house dust mites have included environmental manipulation in homes in an attempt to reduce humidity below a level that favors mite survival. This appears to have some benefit in Scandinavia, but a previous attempt with mechanical ventilation heat pump recovery (MVHR) units in the UK failed to achieve the desired results. We report a study using an additional central dehumidification modification of the MVHR (MVHRcd) in an attempt to reduce allergen levels in houses of asthmatic subjects. Ten houses of asthmatic patients allergic to dust mites and 10 architectural control houses were studied. The active houses were fitted with an MVHRcd unit in November/December 1994 and activated in January 1995. The active and control houses were monitored continuously for internal temperature and humidity by using digital sensors in the asthmatic and control bedrooms. Dust samples were collected to determine allergen levels at baseline (January 1994) and 3, 6, 9, and 15 months after switching on the units. The winter seasonal average humidity fell from 50% relative humidity (RH) in control bedrooms to 37% RH in asthmatic bedrooms compared with 72% RH in the ambient air as measured on the intake of the MVHRcd systems. There was no corresponding change in seasonal mean temperature within the houses. Although the temperature and humidity weekly and seasonal means remained below the study target of 45% RH or 7 g/kg absolute humidity at 21 degrees C, there were transient rises in humidity detected by the sensors in the houses with MVHRcd systems. Allergen levels fell both in active and control houses during the study period, but there was no significant advantage gained from the installation of MVHRcd systems. The MVHRcd system failed to confer a benefit in terms of mite allergen reduction despite apparently adequate control of temperature and humidity.

Hypersensitivity to house dust mite and cockroach is the most common allergy in north of iran.

PubMed

Ghaffari, Javad; Khademloo, Mohammad; Saffar, Mohammad Jafar; Rafiei, Alireza; Masiha, Farzad

2010-12-01

Asthma and allergic rhinitis are among the most common diseases in the world. The aim of this study was to detect, by skin prick test, aeroallergens in allergic patients in Sari, Mazandaran in north of Iran. This is a prospective study of skin prick test of aeroallergens in asthma, allergic rhinitis and their combination with clinical diagnosis. Three hundred and seventy five cases aged between 5 to 50 years, were referred to Tooba and Boo-Ali allergic centers of Mazandaran University of Medical Sciences between December 2006 and July 2009. The aeroallergens studied included house dust mites (Dermatophagoides farinae, Dermatophagoides pteronyssinus), cockroaches, feather, aspergillus, Alternaria, pigweed, nettle, oak and maple. Of the studied individuals, 175 cases were males (46.7%) and 200 were females (53.3%), of which 156 (n=41.5%) reacted to allergen extracts. In asthma, allergic rhinitis and their combination, the respective positive percentages were 26.6%, 22.9%, and 32.6% for Dermatophagoides farinae; 26.6%, 25.3%, and 23.3% for Dermatophagoides pteronyssinus; 12.7%, 17.4%, and 11.6% for cockroaches and 16.5%, 4.7%, and 7.0% for the feather. Other allergens were positive up to 5 percent. Total IgE levels were elevated in 56.4%, 53% and 60.5% of asthmatic, allergic rhinitis and the combination group, respectively. Eosinophils count was elevated in 40.5%, 33.2% and 37.2% of the same groups, respectively. The hypersensitivity to house dust mites is very common in north of Iran which may be attributed to the warm and humid weather of this area.

[Research on dust mite allergen gathered from filters of air-conditioners].

PubMed

Zhan, Xiao-dong; Wu, Hua; Hu, Hui-min; Li, Chao-pin

2015-12-01

To discuss the relation between the dust mite allergen (Der) in air-conditioner filters and the asthma attack. The dust samples were collected from the filters of air-conditioners in dining rooms, shopping malls, hotels and households, respectively. The concentrations of Der f 1 and Der p1 were detected by ELISA, and the dust mite immune activities were determined by dot-ELISA. The concentrations of Der f 1 in the dining rooms, shopping malls, hotels and households were 1.52, 1.24, 1.31 µg/g and 1.46 µg/g respectively, and the concentrations of Der p 1 were 1.23, 1.12, 1.16 µg/ g and 1.18 µg, respectively. One hour after the running of air-conditioners, the concentrations of Der f 1 and Der p 1 in the air were higher than those before the running of air-conditioners, and the differences were significant (P < 0.05). Additionally, the dot-ELISA results revealed that the allergen extracted from the dust was capable of reacting with IgE from the sera of asthma mice allergic to dust mites. Der f 1 and Der p 1 appear abundantly in the filters of air-conditioners in domestic houses in Wuhu City, and the allergens can induce asthma.

Maternal house dust mite exposure during pregnancy enhances severity of house dust mite-induced asthma in murine offspring.

PubMed

Richgels, Phoebe K; Yamani, Amnah; Chougnet, Claire A; Lewkowich, Ian P

2017-11-01

Atopic status of the mother and maternal exposure to environmental factors are associated with increased asthma risk. Moreover, animal models demonstrate that exposure to allergens in strongly sensitized mothers influences offspring asthma development, suggesting that in utero exposures can influence offspring asthma. However, it is unclear whether maternal exposure to common human allergens such as house dust mite (HDM), in the absence of additional adjuvants, influences offspring asthma development. We sought to determine whether maternal HDM exposure influences asthma development in offspring. Pregnant female mice were exposed to PBS or HDM during pregnancy. Using offspring of PBS- or HDM-exposed mothers, the magnitude of HDM or Aspergillus fumigatus (AF) extract-induced airway hyperresponsiveness (AHR), airway inflammation, immunoglobulin production, T H 2-associated cytokine synthesis, and pulmonary dendritic cell activity was assessed. Compared with offspring of PBS-exposed mothers, offspring of HDM-exposed mothers demonstrate increased AHR, airway inflammation, T H 2 cytokine production, and immunoglobulin levels and a modest decrease in the phagocytic capacity of pulmonary macrophage populations following HDM exposure. Increased sensitivity to AF-induced airway disease was not observed. Offspring of HDM-exposed B-cell-deficient mothers also demonstrated increased HDM-induced AHR, suggesting that transfer of maternal immunoglobulins is not required. Our data demonstrate that maternal exposure to HDM during pregnancy increases asthma sensitivity in offspring in an HDM-specific manner, suggesting that vertical transmission of maternal immune responses may be involved. These findings have important implications for regulation of asthma risk, and suggest that exposure to HDM in the developed world may have underappreciated influences on the overall prevalence of allergic asthma. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by

Influence of environmental characteristics and climatic factors on mites in the dust of air-conditioner filters.

PubMed

Wu, J; Liu, Z G; Ran, P X; Wang, B

2009-12-01

To investigate mites in the dust of air-conditioner filters (MACF) in China, a total of 652 dust samples were collected from six cities: Guangzhou (n = 129), Nanchang (n = 127), Shanghai (n = 113), Xian (n = 93), Beijing (n = 93), and Shenyang (n = 79). Tarsonemus granarius was the most dominant species (87.2%). Dermatophagoides pteronyssinus and Dermatophagoides farinae only represented 7.0 and 3.0% of total mites, respectively. With latitude increasing, both mite occurrence rate (P < 0.001) and density (mites/g dust) (P < 0.001) were significantly decreasing. Multivariate regression analysis suggested that the annual average temperature and minimum temperature in different cities had dominant influences on MACF density. The logistic regression analysis revealed that the presence of MACF was positively associated with air-conditioner age, utilization time and power. Wall and window type air-conditioner had higher risk of finding MACF than the floor type air-conditioner. As far as the cleaning interval time of ACF was concerned, higher risk ratio and the highest density of MACF were found in the time stage of >3, < or =12 months. It was also suggested that house type could influence the presence of MACF. A negative association between the house floor and the MACF prevalence was found as well. Mites present in the dust of air-conditioner filters are potential indoor threat to asthma and allergy sufferers. In this study, we find that the storage mite Tarsonemus granarius is the predominant species of mites in the dust of air-conditioner filters (MACF). Thus, the possible clinical importance of T. granarius should cause more our attentions in the future. The abundance and distribution of MACF are also found significantly varied in different climatic regions of China. When we try to assess the possible risk of MACF, more attentions should be focused on subtropical region than temperate region. The influence analysis of environmental characteristics on the prevalence of

Validation of a novel epicutaneous delivery system for patch testing of house dust mite-hypersensitive dogs.

PubMed

Olivry, Thierry; Linder, Keith E; Paps, Judy S; Bizikova, Petra; Dunston, Stan; Donne, Nathalie; Mondoulet, Lucie

2012-12-01

Patch tests with allergens are used for the evaluation of cellular hypersensitivity to food and environmental allergens in dogs and humans with atopic dermatitis. Viaskin is a novel allergen epicutaneous delivery system that enhances epidermal allergen capture by immune cells. To compare the use of Viaskin and Finn chamber patch tests in dogs hypersensitive to mite allergens. Empty control or Dermatophagoides farinae house dust mite-containing Viaskin or Finn chamber patches were applied to the thoracic skin of six mite-hypersensitive Maltese-beagle crossbred atopic dogs. Lesions were graded 49 and 72 h after patch test application, and skin biopsies were collected after 72 h. Overall microscopic inflammation, eosinophil and T-lymphocyte infiltrations were scored. Positive macroscopic patch test reactions developed at five of six Viaskin application sites and four of six Finn chamber application sites. Median microscopic epidermal and dermal inflammation, as well as eosinophil and CD3 T-lymphocyte dermal scores were always higher in biopsies collected at Viaskin than at Finn chamber sites. Microscopic inflammation scores were significantly higher after mite allergen-containing Viaskin compared with empty patches, but this was not the case for mite-containing Finn chambers compared with control chambers. Scores obtained using Viaskin were not significantly different from those obtained using Finn chambers. Macroscopic and microscopic scores were significantly correlated. In mite-allergic dogs, Viaskin epicutaneous delivery systems appear to induce stronger allergen-specific inflammation than currently used Finn chamber patch tests. Consequently, Viaskin patches might offer a better alternative for screening cellular hypersensitivity to food and environmental allergens. © 2012 The Authors. Veterinary Dermatology © 2012 ESVD and ACVD.

Generation of a transgenic rice seed-based edible vaccine against house dust mite allergy.

PubMed

Yang, Lijun; Kajiura, Hiroyuki; Suzuki, Kazuya; Hirose, Sakiko; Fujiyama, Kazuhito; Takaiwa, Fumio

2008-01-11

As an alternative approach to conventional allergen-specific immunotherapy, transgenic rice seed expressing a major house dust mite (HDM) allergen, Der p 1, was developed as an edible vaccine. The C-terminal KDEL-tagged Der p 1 allergen specifically accumulated in seed endosperm tissue under the control of the endosperm-specific GluB1 promoter. Der p 1 reached a maximum concentration of 58 microg/grain and was deposited in the endoplasmic reticulum (ER)-derived protein body I (PB-I). Plant-derived Der p 1 was posttranslationally modified with high-mannose-type glycan structures. Glycosylated Der p 1 displayed reduced IgE binding capacity in comparison with its unglycosylated counterpart in vitro. Our results indicate that transgenic Der p 1 rice seeds are a safe, potential oral delivery vaccine for the treatment of HDM allergy.

Cerium dioxide nanoparticles exacerbate house dust mite induced type II airway inflammation.

PubMed

Meldrum, Kirsty; Robertson, Sarah B; Römer, Isabella; Marczylo, Tim; Dean, Lareb S N; Rogers, Andrew; Gant, Timothy W; Smith, Rachel; Tetley, Terry D; Leonard, Martin O

2018-05-23

Nanomaterial inhalation represents a potential hazard for respiratory conditions such as asthma. Cerium dioxide nanoparticles (CeO 2 NPs) have the ability to modify disease outcome but have not been investigated for their effect on models of asthma and inflammatory lung disease. The aim of this study was to examine the impact of CeO 2 NPs in a house dust mite (HDM) induced murine model of asthma. Repeated intranasal instillation of CeO 2 NPs in the presence of HDM caused the induction of a type II inflammatory response, characterised by increased bronchoalveolar lavage eosinophils, mast cells, total plasma IgE and goblet cell metaplasia. This was accompanied by increases in IL-4, CCL11 and MCPT1 gene expression together with increases in the mucin and inflammatory regulators CLCA1 and SLC26A4. CLCA1 and SLC26A4 were also induced by CeO 2 NPs + HDM co-exposure in air liquid interface cultures of human primary bronchial epithelial cells. HDM induced airway hyperresponsiveness and airway remodelling in mice were not altered with CeO 2 NPs co-exposure. Repeated HMD instillations followed by a single exposure to CeO 2 NPs failed to produce changes in type II inflammatory endpoints but did result in alterations in the neutrophil marker CD177. Treatment of mice with CeO 2 NPs in the absence of HDM did not have any significant effects. RNA-SEQ was used to explore early effects 24 h after single treatment exposures. Changes in SAA3 expression paralleled increased neutrophil BAL levels, while no changes in eosinophil or lymphocyte levels were observed. HDM resulted in a strong induction of type I interferon and IRF3 dependent gene expression, which was inhibited with CeO 2 NPs co-exposure. Changes in the expression of genes including CCL20, CXCL10, NLRC5, IRF7 and CLEC10A suggest regulation of dendritic cells, macrophage functionality and IRF3 modulation as key early events in how CeO 2 NPs may guide pulmonary responses to HDM towards type II inflammation. CeO 2 NPs

Dust Mite Allergy

MedlinePlus

... exposure to the allergen can cause the ongoing (chronic) inflammation associated with asthma. Dust mites eat organic matter ... their debris can cause complications. Sinus infections. Ongoing (chronic) inflammation of tissues in the nasal passages caused by ...

[Inhibition of antisense-endothelin converting enzyme RNA on interleukin-5 released from dust mite-challenged peripheral blood mononuclear cells in patients with allergic asthma].

PubMed

Li, Li; Xu, Ju; Zhong, Nan-shan

2003-09-01

To investigate the effect of antisense endothelin converting enzyme (ECE) RNA on levels of cytokines released from CD(4)(+) lymphocytes in patients with allergic diseases responsive to house dust mites. Peripheral blood mononuclear cells (PBMCs) were separated from 21 patients who were sensitive to dust mites. PBMCs from those patients were divided into two groups. No stimulation group (A group) induded A(1) group (anti-ECE epithelial cells + PBMCs) and A(2) group (control cells + PBMCs). Stimulation group (B group) included B(1) group (anti-ECE epithelial cells + PBMCs + dust mites extract) and B(2) group (control cells + PBMCs + dust mites extract). House dust mite extract (20 microg/ml) was added to the culture of stimulation group as described above. After 72 hours, supernatants from both groups were collected and the levels of IL-5 and IFN-ggr; released into the supernatants were detected by enzyme-linked immunoabsorbent assay. IL-5 levels were increased significantly after treatment with dust mite in twelve of 21 cases. No significant differences of IL-5 were found between the groups of A(1)[(6.0 +/- 1.3) x 10(-9) g/L] and A(2) [(7.5 +/- 1.1) x 10(-9) g/L] before house dust mite stimulation in the 12 cases (P > 0.05), and no significant differences in IFN-ggr; were found between the groups of A(1) [(63 +/- 26) x 10(-9) g/L] and A(2) [(70 +/- 52) x 10(-9) g/L] before house dust mite stimulation (P > 0.05). IL-5 level was increased in both groups after stimulation but it was significantly lower in the B(1) group [(8.2 +/- 1.6) x 10(-9) g/L] than that in the B(2) [(12.0 +/- 1.8) x 10(-9) g/L] (P = 0.047). It seemed that increased IFN-ggr; level after stimulation was higher in B(2) [(153 +/- 71) x 10(-9) g/L] than that in the B(1) group (100 +/- 41) x 10(-9) g/L], but there was no statistic significance (P > 0.05). In addition, our results also showed that the release of IL-5 was significantly increased in those cases with asthma, or asthma plus allergic rhinitis

Crystallization and Preliminary X-ray Analysis of Der f 2, a Potent Allergen Derived from the House Dust Mite

NASA Technical Reports Server (NTRS)

Roeber, Dana; Achari, Aniruddha; Takai, Toshiro; Okumura, Yasushi; Scott, David L.; Curreri, Peter (Technical Monitor)

2002-01-01

Although a number of allergens have been identified and isolated, the underlying molecular basis for the potent immune response is poorly understood. House dust mites (Dermatophugoides sp.) are particularly ubiquitous contributors to atopy in developed countries. The rhinitis, dermatitis, and asthma associated with allergic reactions to these arthropods are often caused by relatively small (125-129 amino acids) mite proteins of unclear biological function. Der f 2, a major allergen from the mite Dermatophagoides farinae, has been recombinantly expressed and characterized. The Der f 2 protein has been crystallized in our laboratory and a native data set collected at a synchrotron source. The crystals belong to the orthorhombic space group I422 with unit cell parameters of a = 95.2 Angstroms, b = 95.2 Angstroms, and c = 103.3 Angstroms. An essentially complete (97.2%) data set has been collected to 2.4 Angstroms. Attempts to solve the crystal structure of Der f 2 by molecular replacement using the available NMR coordinates for either Der f 2 or Der p 2 (the homologous protein from D. pterovssinus) failed to reveal a creditable solution.

Sensitization to allergens of house-dust mite in adults with atopic dermatitis in a cold temperature region.

PubMed

Holm, L; van Hage-Hamsten, M; Ohman, S; Scheynius, A

1999-07-01

An IgE-mediated contact reaction to airborne allergens has been suggested as one important pathogenetic mechanism in atopic dermatitis (AD). The house-dust mite (HDM) might be a common allergen involved. In Scandinavia, sensitization to HDM has been rare, probably because of the cold, dry climate. However, recent studies indicate high levels of domestic mites and HDM allergen in 15-20% of homes in central and northern Sweden. To evaluate the importance of the HDM in patients with AD in the Stockholm region, we screened 81 adult Stockholm residents with AD, for the prevalence and degree of sensitization to the HDM, according to specific IgE (RAST), skin prick test (SPT), and atopy patch test (APT). We also assessed the HDM exposure in their homes and correlated the results with clinical history, severity of the dermatitis, and type of residence during childhood and today. The sensitization rate to HDM was high (56% according to RAST, 24% according to SPT, and 47% according to APT), and 20% of the patients were exposed to HDM allergens in their beds. Mite exposure seemed to aggravate the dermatitis in highly sensitized patients. The results indicate that we have to take the HDM into account when discussing aggravating factors in adult patients with AD in the Stockholm region.

Depigmented and polymerised house dust mite allergoid: allergen content, induction of IgG4 and clinical response.

PubMed

Gallego, M T; Iraola, V; Himly, M; Robinson, D S; Badiola, C; García-Robaina, J C; Briza, P; Carnés, J

2010-01-01

Polymerised allergenic extracts (allergoids) are commonly used in allergen immunotherapy. Clinical efficacy and safety of these extracts have been demonstrated. Recently, allergen sequences have been identified by mass spectrometry in depigmented and polymerised (Dpg-Pol) extracts. The objectives of this study were to investigate the presence of allergens in Dpg-Pol extracts of house dust mite and to analyze the immunological changes induced by these extracts in asthmatic patients enrolled in a double-blind, placebo-controlled study. Dpg-Pol extracts were manufactured and vaccines with a composition of 50% Dermatophagoides pteronyssinus and 50% D. farinae (100 HEPL/ml) were prepared. Allergen composition was analyzed by mass spectrometry. Patients with asthma and rhinoconjunctivitis were treated in a 1-year, double-blind, placebo-controlled, parallel-group study with 6 up-dosing and monthly maintenance injections. Specific IgE and IgG4 titres to D. pteronyssinus, Der p 1 and Der p 2 were measured in patients' sera using the CAP system and direct ELISA experiments. Sequences from the major allergens Der p 1 and Der p 2 and from other allergens were identified in native and Dpg-Pol extracts. There was a statistically significant increase in specific IgG4, a decrease in the ratio of IgE/IgG4 to D. pteronyssinus and a significant increase in specific IgG4 to Der p 1 and Der p 2 in the patients allotted to active treatment. The detection of allergen sequences suggests preservation of major and minor allergens in Dpg-Pol allergoids from house dust mites. Efficacy in asthma treatment and the increase in specific IgG4 seem to be associated with the presence of major allergens in Dpg-Pol allergen extracts. Copyright (c) 2010 S. Karger AG, Basel.

Pyroglyphid mites as a source of work-related allergens.

PubMed

Macan, Jelena; Kanceljak-Macan, Božica; Milković-Kraus, Sanja

2012-01-01

Pyroglyphid mites are primarily associated with allergen exposure at home; hence the name house dust mites. However, we have found numerous studies reporting pyroglyhid mite levels in public and occupational settings. This review presents the findings of house dust mite allergens (family Pyroglyphidae, species Dermatophagoides) as potential work-related risk factors and proposes occupations at risk of house dust mite-related diseases. Pyroglyphid mites or their allergens are found in various workplaces, but clinically relevant exposures have been observed in hotels, cinemas, schools, day-care centres, libraries, public transportation (buses, trains, taxies, and airplanes), fishing-boats, submarines, poultry farms, and churches. Here we propose a classification of occupational risk as low (occasional exposure to mite allergen levels up to 2 μg g(-1)), moderate (exposure between 2 μg g(-1) and 10 μg g(-1)), and high (exposure >10 μg g(-1)). The classification of risk should include factors relevant for indoor mite population (climate, building characteristics, and cleaning schedule). To avoid development or aggravation of allergies associated with exposure to house dust mites at work, occupational physicians should assess exposure risk at work, propose proper protection, provide vocational guidance to persons at risk and conduct pre-employment and periodic examinations to diagnose new allergy cases. Protection at work should aim to control dust mite levels at work. Measures may include proper interior design and regular cleaning and building maintenance.

[Dust mites as occupational allergens in two bakeries of La Habana, Cuba].

PubMed

Fernández-Duro, Bárbara I; Alvarez-Castelló, Mirta; Mateo-Morejón, Mayteé; Luis-Rodríguez, Bárbara; Labrada-Rosado, Alexis

2014-01-01

Occupational allergies are becoming more frequent. The allergens present in the working environment of bakeries, such as mites, are not well identified despite being known risk factors of respiratory diseases. To isolate and identify the species of mites present in two bakeries in La Habana, Cuba, with high sensitization of mites on their workers. A descriptive study was done in which samples were taken by tripled from potential sources of mites in bakeries -as flourin use, spills of wheat on the floors, wheat flour stored in sealed bags, sugar, yeast, granulated baker- that were processed, according to the method of flotation of Hart and Fain (1987) to isolate, identify and count the mites present. Mites were found in samples of wheat flourin use, spills on the floorsand in the wheat flourstored in sealed bags. The species identified were Blomia tropicalis (70%), Tyrophagus putrescentiae (20%) and to a lesser degree Dermatophagoides pteronyssinus and Dermatophagoides siboney. There is a high exposure to house dust mites, particularly to store mites, which constitute a risk factor of occupational allergy to consider.

Protease-Activated Receptor-2 Activation Contributes to House Dust Mite-Induced IgE Responses in Mice

PubMed Central

Post, Sijranke; Heijink, Irene H.; Petersen, Arjen H.; de Bruin, Harold G.; van Oosterhout, Antoon J. M.; Nawijn, Martijn C.

2014-01-01

Aeroallergens such as house dust mite (HDM), cockroach, and grass or tree pollen are innocuous substances that can induce allergic sensitization upon inhalation. The serine proteases present in these allergens are thought to activate the protease-activated receptor (PAR)-2, on the airway epithelium, thereby potentially inducing allergic sensitization at the expense of inhalation tolerance. We hypothesized that the proteolytic activity of allergens may play an important factor in the allergenicity to house dust mite and is essential to overcome airway tolerance. Here, we aimed to investigate the role of PAR-2 activation in allergic sensitization and HDM-induced allergic airway inflammation. In our study, Par-2 deficient mice were treated with two different HDM extracts containing high and low serine protease activities twice a week for a period of 5 weeks. We determined airway inflammation through quantification of percentages of mononuclear cells, eosinophils and neutrophils in the bronchial alveolar lavage fluid and measured total IgE and HDM-specific IgE and IgG1 levels in serum. Furthermore, Th2 and pro-inflammatory cytokines including IL-5, IL-13, Eotaxin-1, IL-17, KC, Chemokine (C-C motif) ligand 17 (CCL17) and thymic stromal lymphopoietin (TSLP), were measured in lung tissue homogenates. We observed that independent of the serine protease content, HDM was able to induce elevated levels of eosinophils and neutrophils in the airways of both wild-type (WT) and Par-2 deficient mice. Furthermore, we show that induction of pro-inflammatory cytokines by HDM exposure is independent of Par-2 activation. In contrast, serine protease activity of HDM does contribute to enhanced levels of total IgE, but not HDM-specific IgE. We conclude that, while Par-2 activation contributes to the development of IgE responses, it is largely dispensable for the HDM-induced induction of pro-inflammatory cytokines and airway inflammation in an experimental mouse model of HDM

Der p 1 suppresses indoleamine 2, 3-dioxygenase in dendritic cells from house dust mite-sensitive patients with asthma.

PubMed

Maneechotesuwan, Kittipong; Wamanuttajinda, Valla; Kasetsinsombat, Kanda; Huabprasert, Sukit; Yaikwawong, Metha; Barnes, Peter J; Wongkajornsilp, Adisak

2009-01-01

Indoleamine 2, 3-dioxygenase (IDO), a tryptophan-degrading enzyme in dendritic cells (DCs), mediates an immunosuppressive effect on activated T lymphocytes. However, little is known about the effect of Der p 1 on IDO in human DCs. The aim was to investigate the effect of Der p 1 on the expression and activity of IDO in monocyte-derived DCs from house dust mite (HDM)-sensitive patients with asthma. Using real-time RT-PCR and HPLC, the expression and activity of IDO were assessed in TNF-alpha-induced mature DCs from HDM-sensitive and nonatopic patients with asthma in response to Der p 1 exposure ex vivo. We also monitored the alteration of IDO activity in Der p 1-pulsed DCs after the coincubation with autologous T cells. With a reliance on its protease activity, Der p 1 suppressed functional IDO in DCs from HDM-sensitive patients with asthma but enhanced IDO activity in DCs from nonatopic patients with asthma. This suppression was maintained by the reciprocally induced IL-4 from the coculturing autologous HDM-sensitive T cells. Conversely, the upregulation of IDO activity in Der p 1-pulsed DCs was maintained by IFN-gamma released from autologous nonatopic T cells and the regulatory T-cell subset. Der p 1 pulsation to sensitive DCs failed to raise regulatory T cells but raised progenitor fractions from cloned HDM-sensitive CD4(+) cells through direct contact and soluble mediators. House dust mite-sensitive DCs exposed to Der p 1 downregulated IDO activity and tipped the T(H)1/T(H)2 cytokine balance toward IL-4, resulting in sustainable IDO suppression.

Crystallization and preliminary X-ray analysis of Der f 2, a potent allergen derived from the house dust mite (Dermatophagoides farinae)

NASA Technical Reports Server (NTRS)

Roeber, Dana; Achari, Aniruddha; Takai, Toshiro; Okumura, Yasushi; Scott, David L.

2003-01-01

Although a number of allergens have been identified and isolated, the underlying molecular basis for the potent immune response is poorly understood. House dust mites (Dermatophagoides sp.) are ubiquitous contributors to atopy in developed countries. The rhinitis, dermatitis and asthma associated with allergic reactions to these arthropods are frequently caused by relatively small (125-129 amino acids) mite proteins of unknown biological function. Der f 2, a major allergen from the mite D. farinae, has been recombinantly expressed, characterized and crystallized. The crystals belong to the tetragonal space group I4(1)22, with unit-cell parameters a = b = 95.2, c = 103.3 A. An essentially complete (97.2%) data set has been collected to 2.4 A at a synchrotron source. Attempts to solve the crystal structure of Der f 2 by molecular replacement using the NMR coordinates for either Der f 2 or Der p 2 (the homologous protein from D. pteronyssinus) failed, but preliminary searches using the crystalline Der p 2 atomic coordinates appear to be promising.

No Concentration Decrease of House Dust Mite Allergens With Rising Altitude in Alpine Regions

PubMed Central

Grafetstätter, Carina; Prossegger, Johanna; Braunschmid, Herbert; Sanovic, Renata; Hahne, Penelope; Pichler, Christina; Thalhamer, Josef

2016-01-01

Purpose Several studies over the past 4 decades have indicated a significant reduction in house dust mite (HDM) and HDM allergen concentration in areas higher than 1,500 m above sea level. These have served as basis of allergen avoidance therapies for HDM allergy and asthma. However, modern construction techniques used in the insulation, heating, and glazing of buildings as well as global warming have changed the environmental parameters for HDM living conditions. The present study revisits the paradigm of decreasing HDM allergen concentrations with increasing altitude in the alpine region of Germany and Austria. Methods A total of 122 dust samples from different abodes (hotels, privates and mountain huts) at different altitudes (400-2,600 m) were taken, and concentrations of HDM allergens were analyzed. Humidity and temperature conditions, and numerous indoor environmental parameters such as fine dust, type of flooring, age of building, and frequency of cleaning were determined. Results HDM allergen concentrations did not significantly change with increasing altitude or relative humidity. At the level of indoor parameters, correlations could be found for different flooring types and the concentration of HDM allergens. Conclusions In contrast to the widespread view of the relationship between altitude and HDM allergen concentrations, clinically relevant concentrations of HDM allergens could be detected in high-lying alpine regions in Austria and Germany. These results indicate that improvement in conditions of asthmatic patients sensitized against HDMs during a stay at high altitude can no longer be ascribed to decreased levels of HDM allergens, instead, other mechanisms may trigger the beneficial effect. PMID:27126724

No Concentration Decrease of House Dust Mite Allergens With Rising Altitude in Alpine Regions.

PubMed

Grafetstätter, Carina; Prossegger, Johanna; Braunschmid, Herbert; Sanovic, Renata; Hahne, Penelope; Pichler, Christina; Thalhamer, Josef; Hartl, Arnulf

2016-07-01

Several studies over the past 4 decades have indicated a significant reduction in house dust mite (HDM) and HDM allergen concentration in areas higher than 1,500 m above sea level. These have served as basis of allergen avoidance therapies for HDM allergy and asthma. However, modern construction techniques used in the insulation, heating, and glazing of buildings as well as global warming have changed the environmental parameters for HDM living conditions. The present study revisits the paradigm of decreasing HDM allergen concentrations with increasing altitude in the alpine region of Germany and Austria. A total of 122 dust samples from different abodes (hotels, privates and mountain huts) at different altitudes (400-2,600 m) were taken, and concentrations of HDM allergens were analyzed. Humidity and temperature conditions, and numerous indoor environmental parameters such as fine dust, type of flooring, age of building, and frequency of cleaning were determined. HDM allergen concentrations did not significantly change with increasing altitude or relative humidity. At the level of indoor parameters, correlations could be found for different flooring types and the concentration of HDM allergens. In contrast to the widespread view of the relationship between altitude and HDM allergen concentrations, clinically relevant concentrations of HDM allergens could be detected in high-lying alpine regions in Austria and Germany. These results indicate that improvement in conditions of asthmatic patients sensitized against HDMs during a stay at high altitude can no longer be ascribed to decreased levels of HDM allergens, instead, other mechanisms may trigger the beneficial effect.

Allergic asthma induced in rhesus monkeys by house dust mite (Dermatophagoides farinae).

PubMed

Schelegle, E S; Gershwin, L J; Miller, L A; Fanucchi, M V; Van Winkle, L S; Gerriets, J P; Walby, W F; Omlor, A M; Buckpitt, A R; Tarkington, B K; Wong, V J; Joad, J P; Pinkerton, K B; Wu, R; Evans, M J; Hyde, D M; Plopper, C G

2001-01-01

To establish whether allergic asthma could be induced experimentally in a nonhuman primate using a common human allergen, three female rhesus monkeys (Macaca mulatta) were sensitized with house dust mite (Dermatophagoides farinae) allergen (HDMA) by subcutaneous injection, followed by four intranasal sensitizations, and exposure to allergen aerosol 3 hours per day, 3 days per week for up to 13 weeks. Before aerosol challenge, all three monkeys skin-tested positive for HDMA. During aerosol challenge with HDMA, sensitized monkeys exhibited cough and rapid shallow breathing and increased airway resistance, which was reversed by albuterol aerosol treatment. Compared to nonsensitized monkeys, there was a fourfold reduction in the dose of histamine aerosol necessary to produce a 150% increase in airway resistance in sensitized monkeys. After aerosol challenge, serum levels of histamine were elevated in sensitized monkeys. Sensitized monkeys exhibited increased levels of HDMA-specific IgE in serum, numbers of eosinophils and exfoliated cells within lavage, and elevated CD25 expression on circulating CD4(+) lymphocytes. Intrapulmonary bronchi of sensitized monkeys had focal mucus cell hyperplasia, interstitial infiltrates of eosinophils, and thickening of the basement membrane zone. We conclude that a model of allergic asthma can be induced in rhesus monkeys using a protocol consisting of subcutaneous injection, intranasal instillation, and aerosol challenge with HDMA.

Allergic Asthma Induced in Rhesus Monkeys by House Dust Mite (Dermatophagoides farinae)

PubMed Central

Schelegle, Edward S.; Gershwin, Laurel J.; Miller, Lisa A.; Fanucchi, Michelle V.; Van Winkle, Laura S.; Gerriets, Joan P.; Walby, William F.; Omlor, Amanda M.; Buckpitt, Alan R.; Tarkington, Brian K.; Wong, Viviana J.; Joad, Jesse P.; Pinkerton, Kent B.; Wu, Reen; Evans, Michael J.; Hyde, Dallas M.; Plopper, Charles G.

2001-01-01

To establish whether allergic asthma could be induced experimentally in a nonhuman primate using a common human allergen, three female rhesus monkeys (Macaca mulatta) were sensitized with house dust mite (Dermatophagoides farinae) allergen (HDMA) by subcutaneous injection, followed by four intranasal sensitizations, and exposure to allergen aerosol 3 hours per day, 3 days per week for up to 13 weeks. Before aerosol challenge, all three monkeys skin-tested positive for HDMA. During aerosol challenge with HDMA, sensitized monkeys exhibited cough and rapid shallow breathing and increased airway resistance, which was reversed by albuterol aerosol treatment. Compared to nonsensitized monkeys, there was a fourfold reduction in the dose of histamine aerosol necessary to produce a 150% increase in airway resistance in sensitized monkeys. After aerosol challenge, serum levels of histamine were elevated in sensitized monkeys. Sensitized monkeys exhibited increased levels of HDMA-specific IgE in serum, numbers of eosinophils and exfoliated cells within lavage, and elevated CD25 expression on circulating CD4+ lymphocytes. Intrapulmonary bronchi of sensitized monkeys had focal mucus cell hyperplasia, interstitial infiltrates of eosinophils, and thickening of the basement membrane zone. We conclude that a model of allergic asthma can be induced in rhesus monkeys using a protocol consisting of subcutaneous injection, intranasal instillation, and aerosol challenge with HDMA. PMID:11141508

The accumulation of dust mite allergens on mattresses made of different kinds of materials.

PubMed

Visitsunthorn, Nualanong; Chirdjirapong, Varakorn; Pootong, Visanu; Jirapongsananuruk, Orathai; Pacharn, Punchama; Weeravejsukit, Sirirat; Mahakittikun, Vanna; Vichyanond, Pakit

2010-01-01

Different mattress materials may affect the accumulation of allergens. To compare the amount of group 1 dust mite allergens (Der p1 + Der f1) on mattresses made of different kinds of materials before and after use. Sixty new mattresses made of kapok, synthetic fiber, coconut fiber and sponge-like polyurethane, were placed in the house officers' dormitory at Siriraj hospital, Thailand. The dust samples were collected before (0), 1, 2, 3, 6, 9 and 12 months after the mattresses were used. Group 1 dust mite allergens were analyzed using two-site monoclonal antibody ELISA. Der f1 made up 86.7 % of group 1 allergens found in the matress dust. After the 2nd month, only the mean level in sponge-like polyurethane mattress was under 2 microg/g dust (sensitized level). At the 6th month, the mean levels were 13.1 in coconut, 21.7 in kapok and 17.3 microg/g dust in synthetic fiber, all of which were more than 10 microg/g dust (symptomatic level). At the 9th month, the level in sponge-like polyurethane mattress was increased to 11.2 microg/g. At 12th month the level in coconut fiber, sponge-like polyurethane synthetic fiber and kapok mattresses were 20.2, 22.4, 28.9 and 32.2 microg/g dust respectively. The accumulation rate in kapok and synthetic mattresses was significantly higher than coconut and sponge-like polyurethane mattresses. The mean level of group 1 mite allergens exceeded 10 microg/g dust after the 6th month of use in coconut fiber, kapok and synthetic fiber and at the 9th month in sponge-like polyurethane mattress.

Cat, dog and house dust mite allergen levels on children's soft toys.

PubMed

Wu, Francis Fu-Sheng; Wu, Mei-Wen; Ting, Ming-Hui; Crane, Julian; Siebers, Rob

2014-02-01

Children's soft toys are known to harbour house dust mite (HDM) allergens, but little is known whether they harbour cat or dog allergens. The objective of the study was to measure cat (Fel d 1), dog (Can f 1) and HDM allergens on children's soft toys. Dust was collected from 40 children's soft toys and their mattresses. Data were collected on pet ownership. Dust samples were analysed for Fel d 1, Can f 1, Der p 1 and Der f 1 by enzyme-linked immunosorbent assay (ELISA) and results are expressed as median levels with inter-quartile ranges. Thirty-five (87.5%) soft toys had detectable Fel d 1 levels (median: 0.73 µg/g; inter-quartile range: 0.26-2.56 µg/g) while 34 (85%) had detectable Can f 1 levels (1.20 µg/g; 0.53-2.68). Correspondingly, 32 (80%) mattresses had detectable Fel d 1 levels (0.18 µg/g, 0.07-1.01) while 34 (85%) had detectable Can f 1 levels (0.50 µg/g; 0.33-1.06). All mattresses and soft toys had detectable HDM allergen (Der p 1 + Der f 1) levels with soft toys containing about three times higher levels than mattresses. In homes with cats (n = 10) Fel d 1 levels were higher on soft toys than homes without cats (2.49 versus 0.48 µg/g; p = 0.0009). In homes with dogs (n = 25) Can f 1 levels were generally higher on soft toys (1.38 versus 0.63 µg/g; p = 0.10). This study has shown that soft toys can harbour cat and dog allergen as well as HDM allergens, some with very high levels. Cat and dog ownership resulted in higher Fel d 1 and Can f 1 levels on soft toys and mattresses. The levels of Fel d 1, Can f 1 and HDM allergens on soft toys could be of importance to sensitized asthmatic children.

Effect of inhaled dust mite allergen on regional particle deposition and mucociliary clearance in allergic asthmatics**

EPA Science Inventory

Background Acute exacerbations in allergic asthmatics may lead to impaired ability to clear mucus from the airways, a key factor in asthma morbidity. Objective The purpose of this study was to determine the effect of inhaled house dust mite challenge on the regional deposition of...

Group 10 allergens (tropomyosins) from house-dust mites may cause covariation of sensitization to allergens from other invertebrates

PubMed Central

Inam, Muhammad; Ismail, Muhammad; Chaudhary, Farhana Riaz

2012-01-01

Group 10 allergens (tropomyosins) have been assumed to be a major cause of cross-reactivity between house-dust mites (HDMs) and other invertebrates. Despite all of the published data regarding the epidemiology, percent IgE binding and level of sensitization in the population, the role of tropomyosin as a cross-reactive allergen in patients with multiple allergy syndrome still remains to be elucidated. Homology between amino acid sequences reported in allergen databases of selected invertebrate tropomyosins was determined with Der f 10 as the reference allergen. The 66.9 and 54.4% identities were found with selected crustacean and insect species, respectively, whereas only 20.4% identity was seen with mollusks. A similar analysis was performed using reported B-cell IgE-binding epitopes from Met e1 (shrimp allergen) and Bla g7 (cockroach allergen) with other invertebrate tropomyosins. The percent identity in linear sequences was higher than 35% in mites, crustaceans, and cockroaches. The polar and hydrophobic regions in these groups were highly conserved. These findings suggest that tropomyosin may be a major cause of covariation of sensitization between HDMs, crustaceans, and some species of insects and mollusks. PMID:23342293

House Dust Mite Respiratory Allergy: An Overview of Current Therapeutic Strategies.

PubMed

Calderón, Moisés A; Kleine-Tebbe, Jörg; Linneberg, Allan; De Blay, Frédéric; Hernandez Fernandez de Rojas, Dolores; Virchow, Johann Christian; Demoly, Pascal

2015-01-01

Although house dust mite (HDM) allergy is a major cause of respiratory allergic disease, specific diagnosis and effective treatment both present unresolved challenges. Guidelines for the treatment of allergic rhinitis and asthma are well supported in the literature, but specific evidence on the efficacy of pharmacotherapy treatment for known HDM-allergic patients is weaker. The standard diagnostic techniques--skin prick test and specific IgE testing--can be confounded by cross-reactivity. However, component-resolved diagnosis using purified and recombinant allergens can improve the accuracy of specific IgE testing, but availability is limited. Treatment options for HDM allergy are limited and include HDM avoidance, which is widely recommended as a strategy, although evidence for its efficacy is variable. Clinical efficacy of pharmacotherapy is well documented; however, symptom relief does not extend beyond the end of treatment. Finally, allergen immunotherapy has a poor but improving evidence base (notably on sublingual tablets) and its benefits last after treatment ends. This review identifies needs for deeper physician knowledge on the extent and impact of HDM allergy in respiratory disease, as well as further development and improved access to molecular allergy diagnosis. Furthermore, there is a need for the development of better-designed clinical trials to explore the utility of allergen-specific approaches, and uptake of data into guidance for physicians on more effective diagnosis and therapy of HDM respiratory allergy in practice. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

House Dust Mite Der p 1 Effects on Sinonasal Epithelial Tight Junctions

PubMed Central

Henriquez, Oswaldo A.; Beste, Kyle Den; Hoddeson, Elizabeth K.; Parkos, Charles A.; Nusrat, Asma; Wise, Sarah K.

2013-01-01

Background Epithelial permeability is highly dependent upon the integrity of tight junctions, cell-cell adhesion complexes located at the apical aspect of the lateral membrane of polarized epithelial cells. We hypothesize that sinonasal epithelial exposure to Der p 1 house dust mite antigen decreases expression of tight junction proteins (TJPs), representing a potential mechanism for increased permeability and presentation of antigens across the sinonasal epithelial layer. Methods Confluent cultured primary human sinonasal epithelial cells were exposed to recombinant Der p 1 antigen versus control, and transepithelial resistance measurements were performed over 24 hours. Antibody staining for a panel of tight junction proteins was examined with immunofluorescence/confocal microscopy and Western blotting. Tissue for these experiments was obtained from 4 patients total. Results Der p 1 exposed sinonasal cells showed a marked decrease in transepithelial resistance when compared to control cells. In addition, results of Western immunoblot and immunofluorescent labeling demonstrated decreased expression of TJPs claudin-1 and junction adhesion molecule-A (JAM-A) in Der p 1 exposed cultured sinonasal cells versus controls. Conclusion Der p 1 antigen exposure decreases sinonasal epithelium TJP expression, most notably seen in JAM-A and claudin-1 in these preliminary experiments. This decreased TJP expression likely contributes to increased epithelial permeability and represents a potential mechanism for transepithelial antigen exposure in allergic rhinitis. PMID:23592402

Definition of a pool of epitopes that recapitulates the T cell reactivity against major house dust mite allergens.

PubMed

Hinz, D; Oseroff, C; Pham, J; Sidney, J; Peters, B; Sette, A

2015-10-01

Allergens from house dust mites (HDM) are a common cause of asthma. Der p and Der f from Dermatophagoides sp. are strong immunogens in humans. Allergen extracts are used to study T helper (Th2) cell responses to HDM, which are implicated in the development and regulation of allergic disease. To define an epitope mixture that recapitulates, and might substitute for, HDM extract in terms of detecting and characterizing Th2 cell responses. Peripheral blood mononuclear cells (PBMC) from 52 HDM allergic and 10 non-allergic individuals were stimulated with HDM extracts and assayed with a set of 178 peptides spanning mite allergens group Der p 1, 2, 23 and Der f group 1 and 2 allergens. A pool of the most dominant T cell epitopes identified in the present study and from published literature was assembled and tested for ex vivo T cell responses. Correlation with HDM-specific IgE titres was examined. Patterns of T cell reactivity to Der p and Der f - derived peptides revealed a large number of epitopes. Clear patterns of immunodominance were apparent, with HDM allergen group 1 and 2 dominant over group 23. Furthermore, within a given antigen, 6-11 epitopes accounted for the vast majority of responses. Based on these results and published data, a comprehensive dust mite pool (DMP) of epitopes was designed and found to allow detection of ex vivo T cell responses. DMP ex vivo reactivity correlated with HDM-specific IgE titres and was similar to that detected with commonly used HDM extracts. Ex vivo DMP stimulation was associated with a predominant Th2 response in allergic donors, and minor reactivity of T cells producing IFNγ, IL17 and IL10. A detailed map of Der p and Der f antigens defined a pool of epitopes that can be used to detect ex vivo HDM responses. © 2015 John Wiley & Sons Ltd.

A review of the effects of impermeable bedding encasements on dust-mite allergen exposure and bronchial hyper-responsiveness in dust-mite-sensitized patients.

PubMed

Recer, G M

2004-02-01

Sensitization and exposure to dust-mite antigens are causative factors in the development and exacerbation of asthma. Impermeable bedding encasements are considered a first-line treatment to reduce dust-mite antigen exposure in clinical asthma-management guidelines. Public-health recommendations for environmental asthma treatments should be based on the weight of evidence supporting the reliability of environmental interventions so that uncertainties regarding their effectiveness can be accurately communicated to patients, and so that limited public-health resources can be most effectively utilized. To evaluate the strength of a clinical-trial evidence supporting the efficacy of bedding encasements as an asthma treatment. A narrative review was conducted of all clinical trials involving bedding encasement for the treatment of asthma. Collective statistical analyses were also performed to characterize the quantitative effect of bedding encasement on dust-mite allergen exposure and bronchial hyper-responsiveness (BHR) when used by asthma patients. Over 30 clinical trials were reviewed. Of those studies reporting adequate exposure and BHR results, four reported significant reduction in dust-mite allergen exposure and concomitant BHR reduction in active-treatment groups using bedding encasements. In 10 studies, mite-allergen exposure was reportedly decreased during the study, but BHR was not changed in the active-treatment group or was reduced to a similar degree in the active-treatment and control groups. Five other studies reported a lack of significant effect of the intervention on exposure and BHR. Collective paired analyses found that the effect of bedding encasement on allergen exposure and BHR tended toward only a modest, non-significant improvement. Collectively, effects of bedding encasement on BHR and dust-mite allergen exposure were modestly correlated only when the baseline exposure was above 2 microg Type 1 antigen per gram settled dust. Although bedding

DAMP molecules S100A9 and S100A8 activated by IL-17A and house-dust mites are increased in atopic dermatitis.

PubMed

Jin, Shan; Park, Chang Ook; Shin, Jung U; Noh, Ji Yeon; Lee, Yun Sun; Lee, Na Ra; Kim, Hye Ran; Noh, Seongmin; Lee, Young; Lee, Jeung-Hoon; Lee, Kwang Hoon

2014-12-01

S100A9 and S100A8 are called damage-associated molecular pattern (DAMP) molecules because of their pro-inflammatory properties. Few studies have evaluated S100A9 and S100A8 function as DAMP molecules in atopic dermatitis (AD). We investigated how house-dust mites affect S100A9 and S100A8 expression in Th2 cytokine- and Th17 cytokine-treated keratinocytes, and how secretion of these molecules affects keratinocyte-derived cytokines. Finally, we evaluated expression of these DAMP molecules in AD patients. S100A9 expression and S100A8 expression were strongly induced in IL-17A- and Dermatophagoides (D.) farinae-treated keratinocytes, respectively. Furthermore, co-treatment with D. farinae and IL-17A strongly increased expression of S100A9 and S100A8 compared with D. farinae-Th2 cytokine co-treatment. The IL-33 mRNA level increased in a dose-dependent manner in S100A9-treated keratinocytes, but TSLP expression did not change. S100A8/A9 levels were also higher in the lesional skin and serum of AD patients, and correlated with disease severity. Taken together, S100A9 and S100A8 may be involved in inducing DAMP-mediated inflammation in AD triggered by IL-17A and house-dust mites. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Pyroglyphid mites, xerophilic fungi and allergenic activity in dust from hospital mattresses.

PubMed

v d Lustgraaf, B; Jorde, W

1977-12-01

Dust from mattresses of different composition and age was analysed for mites, xerophilic fungi and allergenic activity. The mites of the genus Demodex were the most abundant (58.2 per cent). Also pyroglyphid mites occurred commonly (36.6 per cent). Pyroglyphid mites were present in small numbers (mean: 1 specimen/0.2 g of dust) in 12 out of the 17 older polyester-foam mattresses. The 11 cotton-horsechair mattresses and the newly used polyester-foam mattresses (three tested) were without them. The dust from the cotton-horsehair mattresses had a significantly higher allergenic activity than from those of polyester-foam. Xerophilic fungi were isolated in three out of 31 mattresses. The species isolated belonged to the genus Aspergillus and Eurotium. E. repens occurred most frequently. Disinfection of mattresses was suggested to have a negative influence on the occurrence of mites and fungi.

Mould-devouring mites differ in guanine excretion from dust-eating Acari, a possible error source in mite allergen exposure studies.

PubMed

Kort, H S; Schober, G; Koren, L G; Scharringa, J

1997-08-01

Measurement of guanine in dust proved a good assessment of mite allergen exposure. Exposure to mite allergens may lead to atopic inflictions. In a semi-natural test system the development of Dermatophagoides pteronyssinus (Trouessart) and Glycyphagus domesticus (De Geer), and the presence of their guanine excretion, was examined in a dust-soiled and mouldy environment. Mites were counted after heat-escape, and guanine was detected by means of capillary zone electrophoresis. For each species, 50 mites randomly taken, were inoculated on soiled test-surfaces of 10 x 10 cm. Rough wooden board, gypsum board, tufted carpet, and a self-made mattress representing wall surfaces and home-textiles, respectively, were used. Eight weeks after inoculation with mites only, the surfaces were all mould ridden, and mite and guanine measurements were taken. The Spearman rank correlation test and the Mann-Whitney U-test were used in statistical analysis. The confidence limit was set at 1%. Among the various test-surfaces, no differences were found regarding total mite numbers and amount of guanine present (P > 0.01). For the dust-eating mite D. pteronyssinus, total mite numbers correlated with the amount of guanine present (P = 0.002) on all inoculated surfaces, indicating feeding on the protein-rich dust. For the mould devouring mite G. domesticus, however, no such correlation was found (P = 0.72). Apparently, they mainly consumed fungal carbohydrates during this experiment. The allergological relevance of storage mites has been under discussion for the last 25 years. In humid homes, these mites will feed almost exclusively on fungi and may produce allergenic or irritating substances different from those arising on protein-rich laboratory media used in allergen extract production or present in carpets, bedding and furniture.

House dust mite allergen Der p 1 effects on sinonasal epithelial tight junctions.

PubMed

Henriquez, Oswaldo A; Den Beste, Kyle; Hoddeson, Elizabeth K; Parkos, Charles A; Nusrat, Asma; Wise, Sarah K

2013-08-01

Epithelial permeability is highly dependent upon the integrity of tight junctions, which are cell-cell adhesion complexes located at the apical aspect of the lateral membrane of polarized epithelial cells. We hypothesize that sinonasal epithelial exposure to Der p 1 house dust mite antigen decreases expression of tight junction proteins (TJPs), representing a potential mechanism for increased permeability and presentation of antigens across the sinonasal epithelial layer. Confluent cultured primary human sinonasal epithelial cells were exposed to recombinant Der p 1 antigen vs control, and transepithelial resistance measurements were performed over 24 hours. Antibody staining for a panel of TJPs was examined with immunofluorescence/confocal microscopy and Western blotting. Tissue for these experiments was obtained from 4 patients total. Der p 1 exposed sinonasal cells showed a marked decrease in transepithelial resistance when compared to control cells. In addition, results of Western immunoblot and immunofluorescent labeling demonstrated decreased expression of TJPs claudin-1 and junction adhesion molecule-A (JAM-A) in Der p 1-exposed cultured sinonasal cells vs controls. Der p 1 antigen exposure decreases sinonasal epithelium TJP expression, most notably seen in JAM-A and claudin-1 in these preliminary experiments. This decreased TJP expression likely contributes to increased epithelial permeability and represents a potential mechanism for transepithelial antigen exposure in allergic rhinitis. © 2013 ARS-AAOA, LLC.

Interleukin-21-Producing CD4(+) T Cells Promote Type 2 Immunity to House Dust Mites.

PubMed

Coquet, Jonathan M; Schuijs, Martijn J; Smyth, Mark J; Deswarte, Kim; Beyaert, Rudi; Braun, Harald; Boon, Louis; Karlsson Hedestam, Gunilla B; Nutt, Steven L; Hammad, Hamida; Lambrecht, Bart N

2015-08-18

Asthma is a T helper 2 (Th2)-cell-mediated disease; however, recent findings implicate Th17 and innate lymphoid cells also in regulating airway inflammation. Herein, we have demonstrated profound interleukin-21 (IL-21) production after house dust mite (HDM)-driven asthma by using T cell receptor (TCR) transgenic mice reactive to Dermatophagoides pteronyssinus 1 and an IL-21GFP reporter mouse. IL-21-producing cells in the mediastinal lymph node (mLN) bore characteristics of T follicular helper (Tfh) cells, whereas IL-21(+) cells in the lung did not express CXCR5 (a chemokine receptor expressed by Tfh cells) and were distinct from effector Th2 or Th17 cells. Il21r(-/-) mice developed reduced type 2 responses and the IL-21 receptor (IL-21R) enhanced Th2 cell function in a cell-intrinsic manner. Finally, administration of recombinant IL-21 and IL-25 synergistically promoted airway eosinophilia primarily via effects on CD4(+) lymphocytes. This highlights an important Th2-cell-amplifying function of IL-21-producing CD4(+) T cells in allergic airway inflammation. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of acupuncture on house dust mite specific IgE, substance P, and symptoms in persistent allergic rhinitis.

PubMed

McDonald, John Leslie; Smith, Peter K; Smith, Caroline A; Changli Xue, Charlie; Golianu, Brenda; Cripps, Allan W

2016-06-01

Clinical evidence suggests that acupuncture improves symptoms in persistent allergic rhinitis, but the physiologic basis of these improvements is not well understood. A randomized, sham-controlled trial of acupuncture for persistent allergic rhinitis in adults investigated possible modulation of mucosal immune responses. A total of 151 individuals were randomized into real and sham acupuncture groups (who received twice-weekly treatments for 8 weeks) and a no acupuncture group. Various cytokines, neurotrophins, proinflammatory neuropeptides, and immunoglobulins were measured in saliva or plasma from baseline to 4-week follow-up. Statistically significant reduction in allergen specific IgE for house dust mite was seen only in the real acupuncture group, from 18.87 kU/L (95% CI, 10.16-27.58 kU/L) to 17.82 kU/L (95% CI, 9.81-25.83 kU/L) (P = .04). A mean (SE) statistically significant down-regulation was also seen in proinflammatory neuropeptide substance P (SP) 18 to 24 hours after the first treatment from 408.74 (299.12) pg/mL to 90.77 (22.54) pg/mL (P = .04). No significant changes were seen in the other neuropeptides, neurotrophins, or cytokines tested. Nasal obstruction, nasal itch, sneezing, runny nose, eye itch, and unrefreshed sleep improved significantly in the real acupuncture group (postnasal drip and sinus pain did not) and continued to improve up to 4-week follow-up. Acupuncture modulated mucosal immune response in the upper airway in adults with persistent allergic rhinitis. This modulation appears to be associated with down-regulation of allergen specific IgE for house dust mite, which this study is the first to report. Improvements in nasal itch, eye itch, and sneezing after acupuncture are suggestive of down-regulation of transient receptor potential vanilloid 1. Australian New Zealand Clinical Trials Registry Identifier: ACTRN 12610001052022. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights

Cognitive Factors Mediate Placebo Responses in Patients with House Dust Mite Allergy

PubMed Central

Benson, Sven; Rueckert, Annika; Hillen, Uwe; Schadendorf, Dirk; Schedlowski, Manfred

2013-01-01

Background Placebo effects have been reported in type I allergic reactions. However the neuropsychological mechanisms steering placebo responses in allergies are largely unknown. The study analyzed whether and to what extend a conditioned placebo response is affecting type I allergic reactions and whether this response can be reproduced at multiple occasions. Methods 62 patients with house dust mite allergy were randomly allocated to either a conditioned (n = 25), sham-conditioned (n = 25) or natural history (n = 12) group. During the learning phase (acquisition), patients in the conditioned group received the H1-receptor antagonist desloratadine (5mg) (unconditioned stimulus/US) together with a novel tasting gustatory stimulus (conditioned stimulus/CS). Patients in the sham-conditioned control group received the CS together with a placebo pill. After a wash out time of 9 days patients in the conditioned and sham-conditioned group received placebo pills together with the CS during evocation. Allergic responses documented by wheal size after skin prick test and symptom scores after nasal provocation were analyzed at baseline, after last desloratadine treatment and after the 1st and 5th CS re-exposure. Results Both conditioned and sham-conditioned patients showed significantly decreased wheal sizes after the 1st CS-evocation and significantly decreased symptom scores after the 1st as well as after the 5th evocation compared to the natural history control group. Conclusions These results indicate that placebo responses in type I allergy are not primarily mediated by learning processes, but seemed to be induced by cognitive factors such as patients’ expectation, with these effects not restricted to a single evocation. PMID:24260254

Evaluation of HEPA vacuum cleaning and dry steam cleaning in reducing levels of polycyclic aromatic hydrocarbons and house dust mite allergens in carpets

PubMed Central

Yu, Chang Ho; Yiin, Lih-Ming; Fan, Zhi-Hua (Tina); Rhoads, George G.

2014-01-01

Dry steam cleaning, which has gained recent attention as an effective method to reduce house dust mite (HDM) allergen concentration and loading in carpets, was evaluated in this study for its efficacy in lowering levels of polycyclic aromatic hydrocarbons (PAHs) as well as HDM allergens. Fifty urban homes with wail-to-wall carpets, mostly low-income and with known lead contamination, were studied in 2003 and 2004. Two carpet-cleaning interventions were compared: Repeated HEPA (High Efficiency Particulate Air filtered) vacuuming alone and repeated HEPA vacuuming supplemented with dry steam cleaning. Vacuum samples were collected to measure carpet loading of dust and contaminants immediately before and after cleaning. Paired comparisons were conducted to evaluate the effectiveness of the cleaning protocols in reducing the levels of PAHs and HDM allergens in carpets. The results indicated that both cleaning methods substantially reduced the loading of PAHs and HDM allergens as well as dust in carpets (p < 0.0001). The reductions in loading of dust (64.4%), PAHs (69.1%), and HDM allergens (85.5%), by dry steam cleaning plus repetitive HEPA vacuuming were larger than the reductions by regular HEPA vacuuming alone: dust (55.5%), PAHs (58.6%), and HDM allergens (80.8%), although the difference was statistically significant only for dust and PAHs. We conclude that intensive HEPA vacuum cleaning substantially reduced the loading of PAHs and HDM allergens in carpets in these urban homes and that dry steam cleaning added modestly to cleaning effectiveness. PMID:19137159

Interferon response factor 3 is essential for house dust mite-induced airway allergy.

PubMed

Marichal, Thomas; Bedoret, Denis; Mesnil, Claire; Pichavant, Muriel; Goriely, Stanislas; Trottein, François; Cataldo, Didier; Goldman, Michel; Lekeux, Pierre; Bureau, Fabrice; Desmet, Christophe J

2010-10-01

Pattern-recognition receptors (PRRs) are critically involved in the pathophysiology of airway allergy, yet most of the signaling pathways downstream of PRRs implicated in allergic airway sensitization remain unknown. We sought to study the effects of genetic depletion of interferon response factor (IRF) 3 and IRF7, important transcription factors downstream of various PRRs, in a murine model of house dust mite (HDM)-induced allergic asthma. We compared HDM-induced allergic immune responses in IRF3-deficient (IRF3(-/-)), IRF7(-/-), and wild-type mice. Parameters of airway allergy caused by HDM exposure were strongly attenuated in IRF3(-/-), but not IRF7(-/-), mice compared with those in wild-type mice. Indeed, in HDM-exposed IRF3(-/-) mice HDM-specific T(H)2 cell responses did not develop. This correlated with impaired maturation and migration of IRF3(-/-) lung dendritic cells (DCs) on HDM treatment. Furthermore, adoptive transfer of HDM-loaded DCs indicated that IRF3(-/-) DCs had an intrinsic defect rendering them unable to migrate and to prime HDM-specific T(H)2 responses. Intriguingly, we also show that DC function and allergic airway sensitization in response to HDM were independent of signaling by type I interferons, the main target genes of IRF3. Through its role in DC function, IRF3, mainly known as a central activator of antiviral immunity, is essential for the development of T(H)2-type responses to airway allergens. Copyright © 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Effect of freezing, hot tumble drying and washing with eucalyptus oil on house dust mites in soft toys.

PubMed

Chang, Chin-Fu; Wu, Francis Fu-Sheng; Chen, Chi-Ying; Crane, Julian; Siebers, Rob

2011-09-01

Soft toys are a major source of house dust mites (HDM) and HDM allergens, and sleeping with soft toys is a significant risk factor for HDM sensitization. We studied three techniques to eliminate HDM from soft toys, namely freezing, hot tumble drying and washing with eucalyptus oil. Thirty-six toys (12 in each treatment group) were enumerated for live HDM by the heat escape method before and after freezing overnight, hot tumble drying for 1 h and washing in 0.2% to 0.4% eucalyptus oil. Freezing, hot tumble drying and washing with eucalyptus oil resulted in significant reductions in live HDM, an average reduction of 95.1%, 89.1% and 95.1%, respectively. Additionally, washing with eucalyptus oil resulted in a significant reduction in HDM allergens as well from a geometric mean of 9.12 μg/g to 0.37 μg/g (p = 0.033). These three HDM elimination techniques give parents of infants effective and acceptable methods of limiting HDM exposure. © 2011 John Wiley & Sons A/S.

T Follicular Helper Cell Plasticity Shapes Pathogenic T Helper 2 Cell-Mediated Immunity to Inhaled House Dust Mite.

PubMed

Ballesteros-Tato, André; Randall, Troy D; Lund, Frances E; Spolski, Rosanne; Leonard, Warren J; León, Beatriz

2016-02-16

Exposure to environmental antigens, such as house dust mite (HDM), often leads to T helper 2 (Th2) cell-driven allergic responses. However, the mechanisms underlying the development of these responses are incompletely understood. We found that the initial exposure to HDM did not lead to Th2 cell development but instead promoted the formation of interleukin-4 (IL-4)-committed T follicular helper (Tfh) cells. Following challenge exposure to HDM, Tfh cells differentiated into IL-4 and IL-13 double-producing Th2 cells that accumulated in the lung and recruited eosinophils. B cells were required to expand IL-4-committed Tfh cells during the sensitization phase, but did not directly contribute to disease. Impairment of Tfh cell responses during the sensitization phase or Tfh cell depletion prevented Th2 cell-mediated responses following challenge. Thus, our data demonstrate that Tfh cells are precursors of HDM-specific Th2 cells and reveal an unexpected role of B cells and Tfh cells in the pathogenesis of allergic asthma. Copyright © 2016 Elsevier Inc. All rights reserved.

Inhibitory effects of Drynaria fortunei extract on house dust mite antigen-induced atopic dermatitis in NC/Nga mice.

PubMed

Sung, Yoon-Young; Kim, Dong-Seon; Yang, Won-Kyung; Nho, Kyoung Jin; Seo, Hyeong Seok; Kim, Young Sang; Kim, Ho Kyoung

2012-10-31

Drynaria fortunei (Kunze) J. Sm has been widely used in traditional medicine for the treatment of inflammation, hyperlipidemia, arteriosclerosis, rheumatism, and bone healing. We investigated the anti-inflammatory effects of a 70% ethanol extract of Drynaria fortunei (DFE). We evaluated the anti-inflammatory effects of topically applied DFE on house dust mite Dermatophargoides farinae-induced atopic dermatitis-like skin lesions in NC/Nga mice. Treatment of NC/Nga mice with DFE reduced the dermatitis score, ear thickness, and serum levels of IgE, IgG1, and IL-6. Histopathological analyses of ear and skin lesions showed inhibition of the thickening of the epidermis and reduced epidermal/dermal infiltration of inflammatory cells. In ear lesions, mRNA expression levels of IL-4, IL-6, and tumor necrosis factor-α were reduced by DFE treatment. DFE inhibited the development of dermatitis-like skin lesions in NC/Nga mice. These results suggest that DFE may be a therapeutic candidate for the treatment of AD. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

House dust mite induces expression of intercellular adhesion molecule-1 in EoL-1 human eosinophilic leukemic cells.

PubMed

Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn; Shin, Myeong Heon

2007-10-01

The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-kappaB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-kappaB and JNK.

House Dust Mite Induces Expression of Intercellular Adhesion Molecule-1 in EoL-1 Human Eosinophilic Leukemic Cells

PubMed Central

Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn

2007-01-01

The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-κB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-κB and JNK. PMID:17982228

Birth month and sensitization to house dust mites in asthmatic children.

PubMed

Yoo, Y; Yu, J; Kang, H; Kim, D K; Koh, Y Y; Kim, C K

2005-10-01

Early exposure to high quantities of allergen has an important role in the incidence of atopic sensitization. In fact, subjects sensitized to house dust mites (HDMs) have a significantly higher proportion of births in the season when HDMs are most abundant. The aim of this study was to investigate whether birth month patterns differ for asthmatic patients sensitized only to HDMs and for those sensitized to HDMs and other allergen(s). Among 2225 patients with asthma, aged 10-16 years, 1642 sensitized to HDMs were identified by skin prick testing. This group was composed of patients sensitized only to HDMs (n = 715) and patients sensitized to HDMs and other allergen(s) (n = 927). The birth month distributions of the group of HDM-sensitive asthmatics or its subgroups were compared with that of a reference population (total live births in the same years as the studied subjects). The risk ratio of a given birth month in relation to all the other months was calculated as an odds ratio (OR) with the corresponding 95% confidence interval (CI). A significant difference in birth month distribution was observed for HDM-sensitive asthmatics (chi(2) = 23.6, P = 0.015), with higher rates of birth in August (OR: 1.23, 95% CI: 1.04-1.46) and September (1.24, 1.04-1.46). When the two subgroups were analyzed separately, significantly more births were noted in August (1.34, 1.06-1.71) and September (1.34, 1.05-1.70) for those sensitized only to HDMs, whereas no such birth month preference was observed for those sensitized to HDMs and other allergen(s). The HDM-positive asthmatics showed a greater proportion of births in August and September, which correspond to high HDM exposure. However, this birth month pattern was evident in asthmatic-sensitive only to HDMs, but was not observed in those sensitive to HDMs and other allergen(s).

House dust mite-specific immunotherapy alters the basal expression of T regulatory and FcεRI pathway genes.

PubMed

Pevec, Branko; Radulovic Pevec, Mira; Stipic Markovic, Asja; Batista, Irena; Rijavec, Matija; Silar, Mira; Kosnik, Mitja; Korosec, Peter

2012-01-01

Regulatory T (Treg) cells and IgE-mediated signaling pathways could play important roles in the induction of allergen tolerance during house dust mite-specific subcutaneous immunotherapy (HDM-SCIT). Our aim was to compare the basal expression levels of Treg, T helper 1 (Th1) and Th2 transcription factors and components involved in IgE-mediated signaling in healthy subjects with those in HDM-allergic patients both untreated and successfully treated with HDM-SCIT. Thirty-nine HDM-allergic patients who completed a 3- to 5-year course of mite extract SCIT, 20 mite-allergic controls and 25 healthy controls participated in this study. The efficacy of SCIT was monitored using skin-prick tests (SPTs), total immunoglobulin E (tIgE), specific IgE (sIgE), sIgG(4), nasal challenge and visual analog scale (VAS) scores at several time points. The mRNA levels of forkhead box protein 3 (FOXP3), T-BET, GATA-3, FcεRI, spleen tyrosine kinase (Syk), phosphatidylinositol 3 kinase (PI3K) and SH2 domain-containing inositol phosphatase (SHIP) were quantified by real-time RT-PCR using nonstimulated whole blood samples. Decreased wheal sizes and VAS scores, negative challenges and increased sIgG(4) levels indicated that SCIT was effective in the treated patients. Basal expression levels of FOXP3 and GATA-3 decreased and T-BET levels increased in both treated patients and in healthy controls compared to untreated patients. The IgE-mediated pathway kinases Syk and PI3K exhibited reduced expression, whereas SHIP phosphatase levels were elevated in both treated patients and healthy controls relative to untreated patients. The expression levels of FcεRI were not significantly altered. Immunotherapy using HDM extracts results in a modification of the basal expression levels of several IgE-related signaling factors and induces a highly significant upregulation of Th1-response and downregulation of Th2-response transcription factors. Interestingly, this therapy also appears to reduce the basal

The influence of air conditioning, humidity, temperature and other household characteristics on mite allergen concentrations in the northeastern United States.

PubMed

van Strien, R T; Gehring, U; Belanger, K; Triche, E; Gent, J; Bracken, M B; Leaderer, B P

2004-06-01

Information about the influence of housing and occupant characteristics on mite allergen concentrations is crucial to determine which methods could be used to decrease exposure of susceptible subjects. To identify housing and occupant characteristics that are associated with mite allergen concentrations in house dust collected from living rooms and mattresses. We collected dust samples from 750 homes in the northeastern US. The influence of various characteristics on concentrations of mite allergens (Der p 1 and Der f 1) was studied using multiple linear regression analysis. Some characteristics, like absence of air conditioners, the presence of mold or mildew, and a lower temperature were consistently associated with higher concentrations of both mite allergens in dust from all sampling locations. However, none of these factors changed Der p 1 or Der f 1 concentrations by more than a factor of 2. People of white ethnic background had roughly two times higher mite allergen concentrations, while family income, family size, and education level only marginally influenced mite allergen concentrations. Various housing characteristics have some influence on mite allergen concentrations, and could possibly be used to decrease exposure of susceptible subjects. However, only a limited percentage of the variation in mite allergen concentrations was explained by these characteristics.

Genome-wide interaction study of dust mite allergen on lung function in children with asthma.

PubMed

Forno, Erick; Sordillo, Joanne; Brehm, John; Chen, Wei; Benos, Takis; Yan, Qi; Avila, Lydiana; Soto-Quirós, Manuel; Cloutier, Michelle M; Colón-Semidey, Angel; Alvarez, Maria; Acosta-Pérez, Edna; Weiss, Scott T; Litonjua, Augusto A; Canino, Glorisa; Celedón, Juan C

2017-10-01

Childhood asthma is likely the result of gene-by-environment (G × E) interactions. Dust mite is a known risk factor for asthma morbidity. Yet, there have been no genome-wide G × E studies of dust mite allergen on asthma-related phenotypes. We sought to identify genetic variants whose effects on lung function in children with asthma are modified by the level of dust mite allergen exposure. A genome-wide interaction analysis of dust mite allergen level and lung function was performed in a cohort of Puerto Rican children with asthma (Puerto Rico Genetics of Asthma and Lifestyle [PRGOAL]). Replication was attempted in 2 independent cohorts, the Childhood Asthma Management Program (CAMP) and the Genetics of Asthma in Costa Rica Study. Single nucleotide polymorphism (SNP) rs117902240 showed a significant interaction effect on FEV 1 with dust mite allergen level in PRGOAL (interaction P = 3.1 × 10 -8 ), and replicated in the same direction in CAMP white children and CAMP Hispanic children (combined interaction P = .0065 for replication cohorts and 7.4 × 10 -9 for all cohorts). Rs117902240 was positively associated with FEV 1 in children exposed to low dust mite allergen levels, but negatively associated with FEV 1 in children exposed to high levels. This SNP is on chromosome 8q24, adjacent to a binding site for CCAAT/enhancer-binding protein beta, a transcription factor that forms part of the IL-17 signaling pathway. None of the SNPs identified for FEV 1 /forced vital capacity replicated in the independent cohorts. Dust mite allergen exposure modifies the estimated effect of rs117902240 on FEV 1 in children with asthma. Analysis of existing data suggests that this SNP may have transcription factor regulatory functions. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

PKCλ/ι regulates Th17 differentiation and house dust mite-induced allergic airway inflammation.

PubMed

Yang, Yingying; Dong, Panpan; Zhao, Jing; Zhou, Wei; Zhou, Yonghua; Xu, Yongliang; Mei, Congjin; Guo, Fukun; Zheng, Yi; Yang, Jun-Qi

2018-03-01

Asthma is a chronic airway inflammation in which Th2 and Th17 cells play critical roles in its pathogenesis. We have reported that atypical protein kinase (PKC) λ/ι is a new regulator for Th2 differentiation and function. However, the role of PKCλ/ι for Th17 cells remains elusive. In this study, we explored the effect of PKCλ/ι on Th17 cells in the context of ex vivo cell culture systems and an in vivo murine model of allergic airway inflammation with the use of activated T cell-specific conditional PKCλ/ι-deficient mice. Our findings indicate that PKCλ/ι regulates Th17 cells. The secretion of Th17 effector cytokines, including IL-17, IL-21 and IL-22, were inhibited from PKCλ/ι-deficient T cells under non-skewing or Th17-skewing culture conditions. Moreover, the impaired Th17 differentiation and function by the PKCλ/ι-deficiency was associated with the downregulation of Stat3 and Rorγt, key Th17 transcription factors. We developed a model of Th17 and neutrophil-involved allergic airway inflammation by intratracheal inoculation of house dust mites. PKCλ/ι-deficiency significantly inhibited airway inflammations. The infiltrating cells in the lungs and bronchoalveolar lavage fluids were significantly reduced in conditional PKCλ/ι-deficient mice. Th17 effector cytokines were reduced in the bronchoalveolar lavage fluids and lungs at protein and mRNA levels. Thus, PKCλ/ι emerges as a critical regulator of Th17 differentiation and allergic airway hyperresponsiveness. Copyright © 2018 Elsevier B.V. All rights reserved.

Vaccination against IL-33 Inhibits Airway Hyperresponsiveness and Inflammation in a House Dust Mite Model of Asthma

PubMed Central

Lei, Ying; Adner, Mikael; Hellman, Lars; Nilsson, Gunnar

2015-01-01

In several clinical and experimental studies IL-33 and its receptor have been found to play important roles in the development of asthma and allergic airway inflammation. We evaluated the effects of vaccination against IL-33 in a mouse model of airway inflammation induced by house dust mite (HDM) allergen. Balb/c mice received the IL-33 vaccine subcutaneously, followed by intranasal administration of HDM for up to six weeks. Vaccination against IL-33 induced high titers of specific anti-IL-33 IgG antibodies that inhibited HDM-induced airway hyperresponsiveness (AHR) in the conducting airways and tissue damping. The vaccination also attenuated the HDM-induced elevation in the numbers of eosinophils in bronchoalveolar lavage fluid (BALF) and suppressed the accumulation of inflammatory cells in the airways. Furthermore, the levels of IL-17A, IL-25, IL-33 and TSLP in lung tissue homogenates were reduced by vaccination against IL-33. These observations demonstrate that vaccination against IL-33 inhibits HDM-induced development of AHR, airway inflammation and production of inflammatory cytokines. The results also indicate an important role of IL-33 in the regulation of AHR of the distal lung compartments. Thus, administration of such a vaccine is potentially an effective therapeutic tool for treating allergic asthma. PMID:26214807

A 4-Week Model of House Dust Mite (HDM) Induced Allergic Airways Inflammation with Airway Remodeling.

PubMed

Woo, L N; Guo, W Y; Wang, X; Young, A; Salehi, S; Hin, A; Zhang, Y; Scott, J A; Chow, C W

2018-05-02

Animal models of allergic airways inflammation are useful tools in studying the pathogenesis of asthma and potential therapeutic interventions. The different allergic airways inflammation models available to date employ varying doses, frequency, duration and types of allergen, which lead to the development of different features of asthma; showing varying degrees of airways inflammation and hyper-responsiveness (AHR) and airways remodeling. Models that also exhibit airway remodeling, a key feature of asthma, in addition to AHR and airway inflammation typically require 5-12 weeks to develop. In this report, we describe a 4-week mouse model of house dust mite (HDM)-induced allergic airways inflammation, and compare the phenotypic features of two different doses of HDM exposures (10 µg and 25 µg) for 5 days/week with a well-characterized 8-week chronic HDM model. We found that 4 weeks of intranasal HDM (25 µg in 35 µl saline; 5 days/week) resulted in AHR, airway inflammation and airway remodeling that were comparable to the 8-week model. We conclude that this new 4-week HDM model is another useful tool in studies of human asthma that offers advantages of shorter duration for development and decreased costs when compared to other models that require longer durations of exposure (5-12 weeks) to develop.

Association between HLA genes and dust mite sensitivity in a Brazilian population.

PubMed

da Costa Lima Caniatti, Marcela Caleffi; Borelli, Sueli Donizete; Guilherme, Ana Lúcia Falavigna; Tsuneto, Luiza Tamie

2017-02-01

Type I hypersensitivity, also known as IgE-mediated allergy, is a complex, multifactorial condition whose onset and severity are influenced by both genetic and environmental factors. Mite allergens stimulate the production of humoral response (IgE), especially in children, which is closely involved in atopic asthma and rhinitis. This study aimed to investigate the association between HLA class I (-A, -B, and -C), and HLA class II (-DRB1) genes in individuals sensitive to dust mites (Dermatophagoides farinae, Dermatophagoides pteronyssinus, or Blomia tropicalis) and mite-insensitive controls. 396 participants were grouped as mite-sensitive and mite-insensitive according to immediate hypersensitivity as determined by skin-prick tests, and to HLA genotyping by polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO). After chi-square heterogeneity testing no significant differences were observed in HLA-A, B, and C genes, except for the HLA-DRB1 locus, which, showed a negative association for DRB1∗04, between mite-sensitive and mite-insensitive individuals. In high resolution, DRB1∗04:11 allele was significantly different from all other results (P=0.0042, OR=0.26, and 95%CI=0.09-0.70). The analysis stratified by etiologic agent confirmed these associations. Our results suggest a possible association between HLA-DRB1 genes and hypersensitivity to dust mites. Copyright © 2016 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Synergistic interaction between the fungus Beauveria bassiana and desiccant dusts applied against poultry red mites (Dermanyssus gallinae).

PubMed

Steenberg, Tove; Kilpinen, Ole

2014-04-01

The poultry red mite, Dermanyssus gallinae, is a major pest in egg production, feeding on laying hens. Widely used non-chemical control methods include desiccant dusts, although their persistence under field conditions is often short. Entomopathogenic fungi may also hold potential for mite control, but these fungi often take several days to kill mites. Laboratory experiments were carried out to study the efficacy of 3 types of desiccant dusts, the fungus Beauveria bassiana and combinations of the two control agents against D. gallinae. There was significant synergistic interaction between each of the desiccant dusts and the fungus, with observed levels of mite mortality significantly higher than those expected for an additive effect (up to 38 % higher). Synergistic interaction between desiccant dust and fungus was found also when different application methods were used for the fungus and at different levels of relative humidity. Although increased levels of mortality were reached due to the synergistic interaction, the speed of lethal action was not influenced by combining the two components. The persistence of the control agents applied separately or in combination did not change over a period of 4 weeks. Overall, combinations of desiccant dusts and fungus conidia seem to hold considerable promise for future non-chemical control of poultry red mites.

Safety of Accelerated Schedules of Subcutaneous Allergen Immunotherapy with House Dust Mite Extract in Patients with Atopic Dermatitis

PubMed Central

Kim, Myoung-Eun; Kim, Jeong-Eun; Sung, Joon-Mo; Lee, Jin-Woo; Choi, Gil-Soon

2011-01-01

The safety of accelerated schedules of allergen immunotherapy (ASAI) in patients with bronchial asthma (BA) has been reported but there are little data on the safety of ASAI for patients with atopic dermatitis (AD). In this study, we investigated the safety of ASAI in patients with AD. Sixty patients with AD and 18 patients with BA sensitized to house dust mites (HDM) were studied. A maximum maintenance dose of HDM extract, adsorbed to aluminum hydroxide, was administered to patients by subcutaneous injection with either a 3-day protocol (rush immunotherapy) or 1-day protocol (ultra-rush immunotherapy). Systemic reactions were observed 4 of 15 patients (26.7%) with AD during rush immunotherapy, 13 of 45 patients (28.9%) with AD during ultra-rush immunotherapy, and 4 of 18 patients (22.2%) with BA during rush immunotherapy (P > 0.05). No severe or near fatal systemic reactions occurred in 78 subjects of this study. Systemic reactions developed within 4 hr after administration of the maximum allergen dose in 20 of 21 patients (95.2%) with AD and BA who showed systemic reactions during rush or ultra-rush immunotherapy. In conclusion, ASAI was safe and well tolerated in patients with AD. ASAI can be a useful therapeutic option for AD. PMID:21935270

House dust mite (Der p 10) and crustacean allergic patients may react to food containing Yellow mealworm proteins.

PubMed

Verhoeckx, Kitty C M; van Broekhoven, Sarah; den Hartog-Jager, Constance F; Gaspari, Marco; de Jong, Govardus A H; Wichers, Harry J; van Hoffen, Els; Houben, Geert F; Knulst, André C

2014-03-01

Due to the imminent growth of the world population, shortage of protein sources for human consumption will arise in the near future. Alternative and sustainable protein sources (e.g. insects) are being explored for the production of food and feed. In this project, the safety of Yellow mealworms (Tenebrio molitor L.) for human consumption was tested using approaches as advised by the European Food Safety Authority for allergenicity risk assessment. Different Yellow mealworm protein fractions were prepared, characterised, and tested for cross-reactivity using sera from patients with an inhalation or food allergy to biologically related species (House dust mite (HDM) and crustaceans) by immunoblotting and basophil activation. Furthermore, the stability was investigated using an in vitro pepsin digestion test. IgE from HDM- and crustacean allergic patients cross-reacted with Yellow mealworm proteins. This cross-reactivity was functional, as shown by the induction of basophil activation. The major cross-reactive proteins were identified as tropomyosin and arginine kinase, which are well known allergens in arthropods. These proteins were moderately stable in the pepsin stability test. Based on these cross-reactivity studies, there is a realistic possibility that HDM- and crustacean allergic patients may react to food containing Yellow mealworm proteins. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sensitization of Children to Storage Mites in Kutahya, Turkey

PubMed Central

Soyucen, Erdogan

2009-01-01

Specific IgE against Acarus siro, Glycphagus domesticus, Tyrophagus putrescentiae, and Lepidoglyphus destructor have been investigated by ELISA in sera of 92 children. Of them, 41 were found to be specific IgE positive (≥ 0.35 IU/ml) against at least one of house dust mite species, Dermatophagoides pteronyssinus and Dermatophagoides farinae, by an immunoblot. In 65.9% of the dust mite-sensitized children, specific IgE against at least one of these mite species was found. Sensitization levels, including co-sensitization cases were found to be 35.7% against A. siro, 24.4% against T. putrescentiae, 31.7% against L. destructor, and 26.8% against G. domesticus. In non-sensitized children, dust mite sensitization level was found to be 25.5%. Breakdown of sensitization by individual species in this group was; against A. siro and T. putrescentiae at 7.8%, against L. destructor at 13.7%, and against G. domesticus at 9.8%. When all children were reckoned, 43.5% was found to be sensitized against at least one storage mite species, with sensitizations against A. siro at 18.5%, T. putrescentiae at 26.1%, L. destructor at 21.7%, and G. domesticus at 17.4%. In dust samples collected from the dwellings of children, distribution of species was found to be A. siro (17%), G. domesticus (23%), T. putrescentiae (29%), L. destructor (25%), and unidentified (6%). In Fisher's chi-square test on SPSS program, there was a relationship between dust mite sensitization and storage mite sensitization (P < 0.05), but no meaningful relationship was found on the basis of individual mite species. PMID:19967087

Nanoparticle conjugation enhances the immunomodulatory effects of intranasally delivered CpG in house dust mite-allergic mice

DOE PAGES

Ballester, Marie; Jeanbart, Laura; de Titta, Alexandre; ...

2015-09-21

An emerging strategy in preventing and treating airway allergy consists of modulating the immune response induced against allergens in the lungs. CpG oligodeoxynucleotides have been investigated in airway allergy studies, but even if promising, efficacy requires further substantiation. We investigated the effect of pulmonary delivery of nanoparticle (NP)-conjugated CpG on lung immunity and found that NP-CpG led to enhanced recruitment of activated dendritic cells and to Th1 immunity compared to free CpG. We then evaluated if pulmonary delivery of NP-CpG could prevent and treat house dust mite-induced allergy by modulating immunity directly in lungs. When CpG was administered as immunomodulatorymore » therapy prior to allergen sensitization, we found that NP-CpG significantly reduced eosinophilia, IgE levels, mucus production and Th2 cytokines, while free CpG had only a moderate effect on these parameters. In a therapeutic setting where CpG was administered after allergen sensitization, we found that although both free CpG and NP-CpG reduced eosinophilia and IgE levels to the same extent, NP conjugation of CpG significantly enhanced reduction of Th2 cytokines in lungs of allergic mice. Taken together, these data highlight benefits of NP conjugation and the relevance of NP-CpG as allergen-free therapy to modulate lung immunity and treat airway allergy.« less

Der p 5 Crystal Structure Provides Insight into the Group 5 Dust Mite Allergens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mueller, G.; Gosavi, R; Krahn, J

2010-01-01

Group 5 allergens from house dust mites elicit strong IgE antibody binding in mite-allergic patients. The structure of Der p 5 was determined by x-ray crystallography to better understand the IgE epitopes, to investigate the biologic function in mites, and to compare with the conflicting published Blo t 5 structures, designated 2JMH and 2JRK in the Protein Data Bank. Der p 5 is a three-helical bundle similar to Blo t 5, but the interactions of the helices are more similar to 2JMH than 2JRK. The crystallographic asymmetric unit contains three dimers of Der p 5 that are not exactly alike.more » Solution scattering techniques were used to assess the multimeric state of Der p 5 in vitro and showed that the predominant state was monomeric, similar to Blo t 5, but larger multimeric species are also present. In the crystal, the formation of the Der p 5 dimer creates a large hydrophobic cavity of {approx}3000 {angstrom}{sup 3} that could be a ligand-binding site. Many allergens are known to bind hydrophobic ligands, which are thought to stimulate the innate immune system and have adjuvant-like effects on IgE-mediated inflammatory responses.« less

Effect of two doses of carbamylated allergoid extract of dust mite on nasal reactivity.

PubMed

Scalone, G; Compalati, E; Bruno, M E; Mistrello, G

2013-11-01

Background and Objective. Single SLIT studies with native allergen extracts support a dose-response effect for clinical and immunological outcomes. Conversely for carbamylated allergoids this dose-response effects is less evident, likely because the threshold for efficacy is more easily reached through the enhanced bioavailability of the extract consequent to the selective chemical modification. Thus this pilot study investigates the dose-response effect on nasal specific reactivity and safety of two unusual doses of carbamylated allergoid in patients mono-sensitized to house dust mites. Methods. A prospective open randomized study involved 6-65 year-old Italian patients with clinically relevant sensitization to house dust mites and positive response to nasal provocation challenge. Monomeric carbamylated allergoid was delivered once daily at the dose of 1000 AU or 2000 AU from June to September 2009, during the lowest level of mites exposure. Primary outcomes were the change of the threshold of allergen concentration for a positive nasal provocation test (NPT) before and after the treatment and the product safety. Secondary outcome was the change  in the mean percentage fall of peak nasal inspiratory flow (PNIF) following nasal challenge. Results. Thirty-four patients were enrolled. Fifteen in group 1 and 14 in group 2 concluded the study. After 12 weeks all patients treated in group 1 and all but one in group 2 showed an increase in the threshold dose provoking a positive NPT. Those with no symptoms onset with the highest dose delivered were 80% in group 1 and 78.6% in group 2 (p=0.92). From first to second challenge, the mean percentage fall of PNIF  was reduced with no statistical difference between groups (p=0.95), and with no difference between the final mean percentage falls (p=0.65). No serious adverse reactions occurred and the frequency of events, all mild, was similar in the two groups. Conclusions. Twelve weeks of carbamylated sublingual allergoid

Tropomyosin or not tropomyosin, what is the relevant allergen in house dust mite and snail cross allergies?

PubMed

Bessot, J C; Metz-Favre, C; Rame, J M; De Blay, F; Pauli, G

2010-02-01

Since tropomyosin is cross reactive in many arthropods, it was assumed that this highly conserved protein could be responsible for cross reactions in house dust mite (HDM) allergic patients who experienced adverse reactions after crustacean and mollusc ingestion. Here we report two clinical cases where the role of tropomyosin is a matter of debate. In the first case, the clinical history, as well as the results of in vivo and in vitro investigations, are in favour of a shrimp allergy without any snail allergy in a patient sensitized to HDM. In the second, the clinical history and the cutaneous tests are in favour of an allergy to snails without any allergy to shrimps in a patient suffering from HDM allergies. The clinical presentation is different in shrimp and snail allergies. In shrimp allergy, symptoms are mainly urticaria or angio-oedema. In snail allergies, adverse reactions are especially severe asthma. Shrimp tropomyosin is a dominant allergen in crustaceans whereas has a much less prominent role in HDM sensitization. Cross reactivities between HDM and snails have been confirmed by inhibition experiments. However, tropomyosin appears to be a minor allergen or even is not involved in snail allergy. It is necessary to clarify the allergens shared between HDMI and snails. The effects of HDM immunotherapy in snail allergy are questioned. Knowledge of taxonomy can contribute to more precise evaluation of cross reactivities between crustaceans and molluscs.

Respiratory allergen from house dust mite is present in human milk and primes for allergic sensitization in a mouse model of asthma.

PubMed

Macchiaverni, P; Rekima, A; Turfkruyer, M; Mascarell, L; Airouche, S; Moingeon, P; Adel-Patient, K; Condino-Neto, A; Annesi-Maesano, I; Prescott, S L; Tulic, M K; Verhasselt, V

2014-03-01

There is an urgent need to identify environmental risk and protective factors in early life for the prevention of allergy. Our study demonstrates the presence of respiratory allergen from house dust mite, Der p 1, in human breast milk. Der p 1 in milk is immunoreactive, present in similar amounts as dietary egg antigen, and can be found in breast milk from diverse regions of the world. In a mouse model of asthma, oral exposure to Der p through breast milk strongly promotes sensitization rather than protect the progeny as we reported with egg antigen. These data highlight that antigen administration to the neonate through the oral route may contribute to child allergic sensitization and have important implications for the design of studies assessing early oral antigen exposure for allergic disease prevention. The up-to-now unknown worldwide presence of respiratory allergen in maternal milk allows new interpretation and design of environmental control epidemiological studies for allergic disease prevention. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The influence of household pets on the composition and quantity of allergenic mite fauna within Irish homes: a preliminary investigation.

PubMed

Clarke, D; Dix, E; Liddy, S; Gormally, M; Byrne, M

2016-03-01

Allergenic mites are responsible for inducing hypersensitive reactions in genetically predisposed people worldwide. Mites in dust from 30 Irish homes with pets (dogs, n = 23; cats, n = 7) were compared with those in 30 homes without pets. House dust mites constituted 78% of all mites recorded, with Dermatophagoides pteronyssinus (Acariformes: Pyroglyphidae) representing 57-72% of mites in furniture and mattresses in both home types compared with only 22% of mites in pet beds. Although storage mites accounted for just 13% of all mites recorded, they represented 46% of mites recorded in pet beds. Median levels of the dust mite allergen Der p 1 (µg/g) in dust samples from mattresses in homes without pets were significantly greater than in mattresses from homes with pets, reflecting the greater densities of D. pteronyssinus found in the former home category. Mite species richness was greater in homes with pets (17 species) than in homes without pets (13 species). This suggests that although the presence of pets can result in a wider variety of epidemiologically important mite species within households, increased competition among mite species may result in a more balanced mite fauna in the home, inhibiting the dominance of any one species and hence lowering allergen-associated risks. © 2015 The Royal Entomological Society.

An experimental model of allergic asthma in cats sensitized to house dust mite or bermuda grass allergen.

PubMed

Norris Reinero, Carol R; Decile, Kendra C; Berghaus, Roy D; Williams, Kurt J; Leutenegger, Christian M; Walby, William F; Schelegle, Edward S; Hyde, Dallas M; Gershwin, Laurel J

2004-10-01

Animal models are used to mimic human asthma, however, not all models replicate the major characteristics of the human disease. Spontaneous development of asthma with hallmark features similar to humans has been documented to occur with relative frequency in only one animal species, the cat. We hypothesized that we could develop an experimental model of feline asthma using clinically relevant aeroallergens identified from cases of naturally developing feline asthma, and characterize immunologic, physiologic, and pathologic changes over 1 year. House dust mite (HDMA) and Bermuda grass (BGA) allergen were selected by screening 10 privately owned pet cats with spontaneous asthma using a serum allergen-specific IgE ELISA. Parenteral sensitization and aerosol challenges were used to replicate the naturally developing disease in research cats. The asthmatic phenotype was characterized using intradermal skin testing, serum allergen-specific IgE ELISA, serum and bronchoalveolar lavage fluid (BALF) IgG and IgA ELISAs, airway hyperresponsiveness testing, BALF cytology, cytokine profiles using TaqMan PCR, and histopathologic evaluation. Sensitization with HDMA or BGA in cats led to allergen-specific IgE production, allergen-specific serum and BALF IgG and IgA production, airway hyperreactivity, airway eosinophilia, an acute T helper 2 cytokine profile in peripheral blood mononuclear cells and BALF cells, and histologic evidence of airway remodeling. Using clinically relevant aeroallergens to sensitize and challenge the cat provides an additional animal model to study the immunopathophysiologic mechanisms of allergic asthma. Chronic exposure to allergen in the cat leads to a variety of immunologic, physiologic, and pathologic changes that mimic the features seen in human asthma.

[Mites in mattress dust and relevant environmental factors in student dormitories in Shenzhen].

PubMed

Wang, Bin; Wu, Jie; Liu, Zhi-gang; Ran, Pi-xin; Gao, Qiao; Luo, Chun-hui; Ai, Mei

2009-02-28

Three hundred and eight mattress dust samples were collected from college dormitories in Shenzhen with a mite prevalence of 88% (271/308). From the samples, 6163 mites were isolated and identified. Dermatophagoides farinae, D. pteronyssinus and Blomia tropicalis were three most abundant species, occupying 29.7%, 21.7% and 17.9%, respectively. It was found that sex of the students, mattress cover (bamboo mat or bed sheet), with or without air conditioner installation, and daily using of air conditioner (<2 h, 2-8 h and >8 h) had no significant influence on the mite prevalence (P>0.05). However, logistic regression analysis revealed that the risk of mite sensitization in male student dormitory was significantly lower than that in female dormitory (OR=0.55, P=0.038), and the risk of using bed sheets was significantly higher than using bamboo mats (OR=2.13, P=0.040). Both mite prevalence and the risk of mite sensitization significantly decreased with higher floor of the dormitory building.

Repellent activity of desiccant dusts and conidia of the entomopathogenic fungus Beauveria bassiana when tested against poultry red mites (Dermanyssus gallinae) in laboratory experiments.

PubMed

Kilpinen, Ole; Steenberg, Tove

2016-11-01

Desiccant dusts and entomopathogenic fungi have previously been found to hold potential against the poultry red mite, which is an important pest in egg production and notoriously difficult to control. Both control agents may cause repellence in other arthropods and potentially also influence control levels adversely when used against the poultry red mite. Five desiccant dust products with good efficacy against the poultry red mite Dermanyssus gallinae caused avoidance behavior in mites when tested in bioassays. The repellent activity was correlated with efficacy, which was found to depend on both dose and relative humidity (RH). However, one desiccant dust was significantly less repellent compared to other dusts with similar levels of efficacy. Further, dry conidia of the fungus Beauveria bassiana were also shown to be repellent to poultry red mites, both when applied on its own and when admixed with a low dose of the desiccant dust Diamol. The pick-up of desiccant dust particles and fungus conidia from treated surfaces by mites did not differ depending on RH, whereas the overall efficacy of the two control agents were significantly higher at 75 than at 85 % RH. In addition, the combined effect of the two substances was synergistic when tested in a bioassay where mites could choose whether to cross a treated surface. This is the first time a member of Acari has been shown to be repelled by desiccant dusts and by conidia of an entomopathogenic fungus.

The effect of encasings on quality of life in adult house dust mite allergic patients with rhinitis, asthma and/or atopic dermatitis.

PubMed

Terreehorst, I; Duivenvoorden, H J; Tempels-Pavlica, Z; Oosting, A J; de Monchy, J G R; Bruijnzeel-Koomen, C A F M; van Wijk, R Gerth

2005-07-01

Environmental control has been put forward as an integral part of the management of house dust mite (HDM) allergy in sensitized patients. To validate this statement allergic disorders involved in HDM allergy--allergic asthma, rhinitis and atopic eczema/dermatitis syndrome (AEDS)--should be taken together and studied in terms of the efficacy of environmental control. Because a generic quality of life questionnaire exceeds the border of disease, this may be used as major outcome parameter. To study the effects of bedding encasings in HDM allergic patients with asthma, rhinitis and AEDS. A total of 224 adult HDM allergic patients with rhinitis and/or asthma and/or dermatitis were randomly allocated impermeable or nonimpermeable encasings for mattress, pillow and duvet. Short form 36 (SF-36) was filled in at baseline and after 12 months. Lower physical (P = 0.01) and emotional (P < 0.001) sumscores were seen in females. Also, the presence of asthma resulted in lower physical sumscore (P = 0.01). However, no effect was seen of encasings on either sumscore. Bedding encasings do not improve quality of life in a mixed population of subjects with combinations with rhinitis, asthma and atopic dermatitis and sensitized to HDMs.

Indoor mite allergens in patients with respiratory allergy living in Porto, Portugal.

PubMed

Plácido, J L; Cuesta, C; Delgado, L; da Silva, J P; Miranda, M; Ventas, P; Vaz, M

1996-09-01

We investigated the levels of mite allergens (Der p 1, Der f 1, Der 2, and Lep d 1) in dust samples from the homes of 59 patients with asthma, 36 sensitized to house-dust mites (HDM) and 23 to grass pollen (controls), living in Porto, northern Portugal. The relationship between exposure and sensitization to HDM and the influence of housing conditions on mite-allergen levels were also evaluated. Der p 1 (median 9.2 micrograms/g) and Der 2 (4.6 micrograms/g) were the main allergens, while Der f 1 and Lep d 1 levels were always < 1 microgram/g dust and undetectable in 11% and 47% of samples, respectively. All HDM-sensitized asthmatics were exposed to Der p 1 levels > 2 micrograms/g and their homes contained significantly higher levels of Der p 1 (median 12.5 vs 6.4 micrograms/g; P = 0.008) and Der 2 (6.2 vs 3.0 micrograms/g; P = 0.004) when compared to the control group. A significant correlation was observed between the exposure to Der p 1 and the wheal area at skin testing with the Dermatophagoides pteronyssinus (Dp) extract (P = 0.01) as well as with serum specific IgE levels to Dp (P = 0.03). Patients with higher levels of serum specific IgE (> or = 17.5 HRU/ml) were also more frequently exposed to Der p 1 levels > or = 10 micrograms/g (P = 0.002). Old homes, presence of carpets, and signs of dampness were conditions associated with significantly higher levels of mite allergens. In conclusion, we found high levels of Der p 1 and Der 2 particularly in the homes of HDM-sensitized patients and we confirm the relationship between exposure and sensitization to HDM, assessed by both in vivo and in vitro methods. In additional to a favorable outdoor climate, we found in our region housing conditions propitious to mite growth, suggesting that specific geographic characteristics must also be taken into account for the correct planning of mite-avoidance measures.

The complete mitochondrial genome of the house dust mite Dermatophagoides pteronyssinus (Trouessart): a novel gene arrangement among arthropods

PubMed Central

Dermauw, Wannes; Van Leeuwen, Thomas; Vanholme, Bartel; Tirry, Luc

2009-01-01

Background The apparent scarcity of available sequence data has greatly impeded evolutionary studies in Acari (mites and ticks). This subclass encompasses over 48,000 species and forms the largest group within the Arachnida. Although mitochondrial genomes are widely utilised for phylogenetic and population genetic studies, only 20 mitochondrial genomes of Acari have been determined, of which only one belongs to the diverse order of the Sarcoptiformes. In this study, we describe the mitochondrial genome of the European house dust mite Dermatophagoides pteronyssinus, the most important member of this largely neglected group. Results The mitochondrial genome of D. pteronyssinus is a circular DNA molecule of 14,203 bp. It contains the complete set of 37 genes (13 protein coding genes, 2 rRNA genes and 22 tRNA genes), usually present in metazoan mitochondrial genomes. The mitochondrial gene order differs considerably from that of other Acari mitochondrial genomes. Compared to the mitochondrial genome of Limulus polyphemus, considered as the ancestral arthropod pattern, only 11 of the 38 gene boundaries are conserved. The majority strand has a 72.6% AT-content but a GC-skew of 0.194. This skew is the reverse of that normally observed for typical animal mitochondrial genomes. A microsatellite was detected in a large non-coding region (286 bp), which probably functions as the control region. Almost all tRNA genes lack a T-arm, provoking the formation of canonical cloverleaf tRNA-structures, and both rRNA genes are considerably reduced in size. Finally, the genomic sequence was used to perform a phylogenetic study. Both maximum likelihood and Bayesian inference analysis clustered D. pteronyssinus with Steganacarus magnus, forming a sistergroup of the Trombidiformes. Conclusion Although the mitochondrial genome of D. pteronyssinus shares different features with previously characterised Acari mitochondrial genomes, it is unique in many ways. Gene order is extremely rearranged

Evaporative Cooler Use Influences Temporal Indoor Relative Humidity but Not Dust Mite Allergen Levels in Homes in a Semi-Arid Climate.

PubMed

Johnston, James D; Tuttle, Steven C; Nelson, Morgan C; Bradshaw, Rebecca K; Hoybjerg, Taylor G; Johnson, Julene B; Kruman, Bryce A; Orton, Taylor S; Cook, Ryan B; Eggett, Dennis L; Weber, K Scott

2016-01-01

Concerns about energy consumption and climate change make residential evaporative coolers a popular alternative to central air conditioning in arid and semi-arid climates. However, evaporative coolers have been shown to significantly increase indoor relative humidity and dust mite allergen levels in some studies, while showing no association in other studies. Improved measurement of temporal fluctuations in indoor relative humidity may help identify factors that promote mite growth in homes in dry climates. Dust samples and continuous indoor relative humidity measurements were collected from homes with central air conditioning and homes with evaporative coolers in Utah. Samples were collected over two seasons, winter/spring (Jan-Apr) and summer (July-Sept), 2014. Dust samples were analyzed for Der p 1 and Der f 1 using a two-site monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) analysis. Housing characteristics including age of home, occupant density, and age of mattresses, furniture, and carpeting were also measured. Positive Der p 1 or Der f 1 samples were found in 25.0% of the homes and there was no difference in mean allergen levels by type of air conditioning. Indoor relative humidity was significantly higher in homes with evaporative coolers compared to those with central air conditioning during the summer. Homes with evaporative coolers also spent significantly more time during summer above 55.0% and 65.0% relative humidity compared to central air homes, but not above 75.0%. Findings from this study suggest that increased humidity from evaporative coolers may not be sufficient to exceed the critical equilibrium humidity or maintain humidity excursions for sufficient duration in relatively larger single-family homes in semi-arid climates to support mite growth and reproduction.

Levels of house dust mite-specific serum immunoglobulin E (IgE) in different cat populations using a monoclonal based anti-IgE enzyme-linked immunosorbent assay.

PubMed

Bexley, Jennifer; Hogg, Janice E; Hammerberg, Bruce; Halliwell, Richard E W

2009-10-01

Levels of serum immunoglobulin E (IgE) specific for the house dust mites (HDMs) Dermatophagoides farinae (DF) and Dermatophagoides pteronyssinus (DP) in 58 cats with clinical signs suggestive of atopic dermatitis (allergic dermatitis cats), 52 cats with no history of allergic or immunological disease (nonallergic cats) and 26 specific pathogen-free (SPF) cats were measured using a monoclonal anti-IgE enzyme-linked immunosorbent assay. Reactivity to both native and reduced HDM allergens was compared. SPF cats had significantly lower levels of HDM-specific serum IgE than cats with allergic dermatitis and nonallergic cats. The difference in levels of HDM-specific IgE in the serum of cats with allergic dermatitis and nonallergic cats was significant for native DF allergen, but not for native DP allergen or reduced HDM allergens. The results suggest that DF in its native form may be a significant allergen in cats with allergic dermatitis. The clinical relevance of these reactions, however, remains to be proven.

[Groups and sources of yeasts in house dust].

PubMed

Glushakova, A M; Zheltikova, T M; Chernov, I Iu

2004-01-01

House dust contains bacteria, mycelial fungi, microarthropods, and yeasts. The house dust samples collected in 25 apartments in Moscow and the Moscow region were found to contain yeasts belonging to the genera Candida, Cryptococcus, Debaryomyces, Rhodotorula, Sporobolomyces, and Trichosporon. The most frequently encountered microorganisms were typical epiphytic yeasts, such as Cryptococcus diffluens and Rhodotorula mucilaginosa, which are capable of long-term preservation in an inactive state. The direct source of epiphytic yeasts occurring in the house dust might be the indoor plants, which were contaminated with these yeasts, albeit to a lesser degree than outdoor plants. Along with the typical epiphytic yeasts, the house dust contained the opportunistic yeast pathogens Candida catenulata, C. guillermondii, C. haemulonii, C. rugosa, and C. tropicalis, which are known as the causal agents of candidiasis. We failed to reveal any correlation between the abundance of particular yeast species in the house dust, residential characteristics, and the atopic dermatitis of the inhabitants.

Evolution and predictive value of IgE responses toward a comprehensive panel of house dust mite allergens during the first 2 decades of life.

PubMed

Posa, Daniela; Perna, Serena; Resch, Yvonne; Lupinek, Christian; Panetta, Valentina; Hofmaier, Stephanie; Rohrbach, Alexander; Hatzler, Laura; Grabenhenrich, Linus; Tsilochristou, Olympia; Chen, Kuan-Wei; Bauer, Carl-Peter; Hoffman, Ute; Forster, Johannes; Zepp, Fred; Schuster, Antje; Wahn, Ulrich; Keil, Thomas; Lau, Susanne; Vrtala, Susanne; Valenta, Rudolf; Matricardi, Paolo Maria

2017-02-01

The evolution of the IgE response to the numerous allergen molecules of Dermatophagoides pteronyssinus is still unknown. We sought to characterize the evolutionary patterns of the IgE response to 12 molecules of D pteronyssinus from birth to adulthood and to investigate their determinants and clinical relevance. We investigated the clinical data and sera of 722 participants in the German Multicenter Allergy Study, a birth cohort started in 1990. Diagnoses of current allergic rhinitis (AR) related to mite allergy and asthma were based on yearly interviews at the ages of 1 to 13 years and 20 years. IgE to the extract and 12 molecules of D pteronyssinus were tested by means of ImmunoCAP and microarray technology, respectively, in sera collected at ages 1, 2, 3, 5, 6, 7, 10, 13, and 20 years. Exposure to mites at age 6 and 18 months was assessed by measuring Der p 1 weight/weight concentration in house dust. One hundred ninety-one (26.5%) of 722 participants ever had IgE to D pteronyssinus extract (≥0.35 kU A /L). At age 20 years, their IgE recognized most frequently Der p 2, Der p 1, and Der p 23 (group A molecules; prevalence, >40%), followed by Der p 5, Der p 7, Der p 4, and Der p 21 (group B molecules; prevalence, 15% to 30%) and Der p 11, Der p 18, clone 16, Der p 14, and Der p 15 (group C molecules; prevalence, <10%). IgE sensitization started almost invariably with group A molecules and expanded sequentially first to group B and finally to group C molecules. Early IgE sensitization onset, parental hay fever, and higher exposure to mites were associated with a broader polymolecular IgE sensitization pattern. Participants reaching the broadest IgE sensitization stage (ie, ABC) had significantly higher risk of mite-related AR and asthma than unsensitized participants. IgE to Der p 1 or Der p 23 at age 5 years or less predicted asthma at school age. Parental hay fever and early exposure to D pteronyssinus allergens promote IgE polysensitization to several

House dust mite sensitization in toddlers predict persistent wheeze in children between eight to fourteen years old

PubMed Central

Llanora, Genevieve V.; Ming, Low Jia; Wei, Lee Ming

2012-01-01

Background Identifying toddlers at increased risk of developing persistent wheeze provides an opportunity for risk-reducing interventions. House dust mite (HDM) allergen sensitization might identify this group of high-risk children. Objective We examined whether a positive skin prick test (SPT) to at least 1 of the 3 HDMs in wheezing toddlers, would serve as a predictor for persistent wheeze at age 8 to 14 years old. Methods A cohort of 78 children, who had wheezing episodes, and underwent SPT to 3 HDMs between the ages of 2 to 5 years old, were enrolled. SPT results were obtained from the National University Hospital database. Four to 9 years later, the children, currently between 8 to 14 years old, were re-assessed for persistence of asthma symptoms and other atopic disorders via a telephone interview. A validated questionnaire on current wheezing and asthma, developed by the International Study of Asthma and Allergies in Childhood, was used. Fisher's exact test was used to evaluate the association between persistence of asthma and a positive SPT. Results Of the 78 children who participated in the study, 42 (53.8%) had a positive SPT and 36 (46.2%) had a negative SPT. Of these, 18 (42.9%) of SPT positive and 7 (19.4%) of SPT negative children had persistence of asthma symptoms. There is a significant association between a positive SPT during the preschool years, and persistence of asthma (p = 0.0314 [<0.05]). Conclusion HDM sensitization at ages 2 to 5 years old in wheezing children predicts persistence of asthma after 4 to 9 years. This in turn may have benefits for management of asthma in this high-risk group. PMID:22872820

PERFLUORINATED COMPOUNDS IN ARCHIVED HOUSE-DUST SAMPLES

EPA Science Inventory

Archived house-dust samples were analyzed for 13 perfluorinated compounds (PFCs). Results show that PFCs are found in house-dust samples, and the data are log-normally distributed. PFOS/PFOA were present in 94.6% and 96.4% of the samples respectively. Concentrations ranged fro...

Quality of life improvement after a three-year course of sublingual immunotherapy in patients with house dust mite and grass pollen induced allergic rhinitis: results from real-life.

PubMed

Novakova, Silviya Mihaylova; Staevska, Maria Toncheva; Novakova, Plamena Ivanova; Yoncheva, Manuela Dimitrova; Bratoycheva, Maria Stoykova; Musurlieva, Nina Mihaylova; Tzekov, Valeri Dimitrov; Nicolov, Dimitar Georgiev

2017-09-29

Along with its high prevalence, the burden of allergic rhinitis rests upon the serious impact on quality of life of patients. Allergic rhinitis is associated with impairments in daily activities, work and school performance, and practical problems. Patients suffer from sleep disorders and emotional problems. Тhe advantages of sublingual immunotherapy on quality of life have only recently begun to emerge. The objective of this prospective real-life study was to evaluate the effect of a three-year course of sublingual immunotherapy with house dust mite (HDM) and grass pollen extracts on quality of life in adults with allergic rhinitis. A total number of 191 adult patients [105 (54,979%) men; mean age 27.3 years (SD-6.14)] with moderate to severe allergic rhinitis and clinically relevant sensitization to house dust mites or grass pollen were prospectively evaluated in the course of management of their disease. Health-related quality of life was assessed by Rhinoconjunctivitis Quality of Life Questionnaire at baseline and after three-year course of sublingual immunotherapy. The mean overall Qol score assessed at baseline and at the end of the third year of treatment decreased significantly in patients treated with HDM extract (from 2.95 to 0.76) as well as with Grass pollen extract (from 2.83 to 1.22) (р < 0.001). The improvements in treated with HDM extract were as followed: activities - 3.52 to 0.68; sleep- 2.48 to 0.31; general problems - 1.79 to 0.49; practical problems - 3.57 to 0.68; nasal symptoms - 3.91 to 0.74; eye symptoms - 2.92 to 0.39; emotions - 3.03 to 0.39. The improvements in grass pollen group were: activities - 3.68 to 1.69; sleep- 1.85 to 0.84; general problems - 1.74 to 0.97; practical problems - 3.52 to 1.37; nasal symptoms - 3.72 to 1.57; eye symptoms - 3.58 to 1.3; emotions - 2.48 to 1.19. Our study conducted in real life provided evidence that a three-year course of SLIT with HDM extract as well as with grass pollen extract significantly

Conventional and monocyte-derived CD11b(+) dendritic cells initiate and maintain T helper 2 cell-mediated immunity to house dust mite allergen.

PubMed

Plantinga, Maud; Guilliams, Martin; Vanheerswynghels, Manon; Deswarte, Kim; Branco-Madeira, Filipe; Toussaint, Wendy; Vanhoutte, Leen; Neyt, Katrijn; Killeen, Nigel; Malissen, Bernard; Hammad, Hamida; Lambrecht, Bart N

2013-02-21

Dendritic cells (DCs) are crucial for mounting allergic airway inflammation, but it is unclear which subset of DCs performs this task. By using CD64 and MAR-1 staining, we reliably separated CD11b(+) monocyte-derived DCs (moDCs) from conventional DCs (cDCs) and studied antigen uptake, migration, and presentation assays of lung and lymph node (LN) DCs in response to inhaled house dust mite (HDM). Mainly CD11b(+) cDCs but not CD103(+) cDCs induced T helper 2 (Th2) cell immunity in HDM-specific T cells in vitro and asthma in vivo. Studies in Flt3l(-/-) mice, lacking all cDCs, revealed that moDCs were also sufficient to induce Th2 cell-mediated immunity but only when high-dose HDM was given. The main function of moDCs was the production of proinflammatory chemokines and allergen presentation in the lung during challenge. Thus, we have identified migratory CD11b(+) cDCs as the principal subset inducing Th2 cell-mediated immunity in the LN, whereas moDCs orchestrate allergic inflammation in the lung. Copyright © 2013 Elsevier Inc. All rights reserved.

Fungal extracellular polysaccharides in house dust as a marker for exposure to fungi: relations with culturable fungi, reported home dampness, and respiratory symptoms.

PubMed

Douwes, J; van der Sluis, B; Doekes, G; van Leusden, F; Wijnands, L; van Strien, R; Verhoeff, A; Brunekreef, B

1999-03-01

Epidemiologic studies have demonstrated an association between indoor fungal growth and respiratory symptoms. However, in only a few studies was fungal exposure actually measured. The purpose of this study was to evaluate the measurement by enzyme immunoassay of extracellular polysaccharides of Aspergillus and Penicillium species (EPS-Asp/Pen ) in house dust as a marker for fungal exposure and to study the relations between EPS-Asp/Pen levels and home dampness and respiratory symptoms in children. Extracts of house dust samples from bedroom and living room floors and mattresses from homes of 31 children with chronic respiratory symptoms and 29 children with no chronic respiratory symptoms were analyzed for EPS-Asp/Pen. EPS-Asp/Pen were readily detectable (40 to 46,513 nanogram equivalent/g dust) in 161 house dust extracts, with highest concentrations in living room floor dust. EPS-Asp/Pen levels were 2 to 3 times higher on carpeted floors than on smooth floors. EPS-Asp/Pen were significantly correlated with total culturable fungi (r = 0.3 to 0.5) and with house dust mite allergens (r = 0.3 to 0.5). EPS-Asp/Pen levels in living room floor dust were positively associated with occupant-reported home dampness. This was not observed for EPS-Asp/Pen in bedroom floor and mattress dust. EPS-Asp/Pen levels in living room floor dust were positively associated with respiratory symptoms. EPS-Asp/Pen in bedroom floor and mattress dust showed a reversed association with respiratory symptoms, possibly because of allergen-avoidance measures taken in the bedroom. The enzyme immunoassay for fungal EPS-Asp/Pen may be a useful method for exposure assessment of indoor fungi.

Characterization of dust from blast furnace cast house de-dusting.

PubMed

Lanzerstorfer, Christof

2017-10-01

During casting of liquid iron and slag, a considerable amount of dust is emitted into the cast house of a blast furnace (BF). Usually, this dust is extracted via exhaust hoods and subsequently separated from the ventilation air. In most BFs the cast house dust is recycled. In this study a sample of cast house dust was split by air classification into five size fractions, which were then analysed. Micrographs showed that the dominating particle type in all size fractions is that of single spherical-shaped particles. However, some irregular-shaped particles were also found and in the finest size fraction also some agglomerates were present. Almost spherical particles consisted of Fe and O, while highly irregular-shaped particles consisted of C. The most abundant element was Fe, followed by Ca and C. These elements were distributed relatively uniformly in the size fractions. As, Cd, Cu, K, Pb, S, Sb and Zn were enriched significantly in the fine size fractions. Thus, air classification would be an effective method for improved recycling. By separating a small fraction of fines (about 10-20%), a reduction of the mass of Zn in the coarse dust recycled in the range of 40-55% would be possible.

[An analysis of skin prick test reactivity to dust mite in overweight and normal weight children with allergic asthma before and after specific immunotherapy].

PubMed

Wang, Jian; Huang, Ying; Zhang, Xue-Li; Huang, Xia; Xu, Xiao-Wen; Liang, Fan-Mei

2016-04-01

To study the skin prick test (SPT) reactivity to house dust mite allergens in overweight and normal weight children with allergic asthma before and after standard subcutaneous specific immunotherapy. Two hundred and fifteen children with allergic asthma who had positive SPT responses to Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF) were enrolled. According to the weight index, they were classified into overweight (n=63) and normal weight groups (n=152). Skin indices (SI) to DP and DF were compared between the two groups at 6 months and 1 year after standard subcutaneous specific immunotherapy. The overweight group had a significantly larger histamine wheal diameter than the normal weight group after controlling the variation in testing time (P<0.05). After controlling the variation in weights, there were significant differences in the SIs to DP and DF before specific immunotherapy and at 6 months and 1 year after specific immunotherapy. At 6 months and 1 year after specific immunotherapy, the SIs to DP and DF were significantly reduced in both groups (P<0.05), and the overweight group had greater decreases in the SIs to DP and DF than the normal weight group. The overweight children with allergic asthma have stronger responses to histamine than the normal weight patients. Specific immunotherapy can reduce the reactivity to dust mite allergens in children with allergic asthma. Within one year after specific immunotherapy, the overweight children with allergic asthma have a significantly greater decrease in the reactivity to dust mite allergens than the normal weight patients.

Evaporative Cooler Use Influences Temporal Indoor Relative Humidity but Not Dust Mite Allergen Levels in Homes in a Semi-Arid Climate

PubMed Central

Johnston, James D.; Tuttle, Steven C.; Nelson, Morgan C.; Bradshaw, Rebecca K.; Hoybjerg, Taylor G.; Johnson, Julene B.; Kruman, Bryce A.; Orton, Taylor S.; Cook, Ryan B.; Eggett, Dennis L.; Weber, K. Scott

2016-01-01

Concerns about energy consumption and climate change make residential evaporative coolers a popular alternative to central air conditioning in arid and semi-arid climates. However, evaporative coolers have been shown to significantly increase indoor relative humidity and dust mite allergen levels in some studies, while showing no association in other studies. Improved measurement of temporal fluctuations in indoor relative humidity may help identify factors that promote mite growth in homes in dry climates. Dust samples and continuous indoor relative humidity measurements were collected from homes with central air conditioning and homes with evaporative coolers in Utah. Samples were collected over two seasons, winter/spring (Jan–Apr) and summer (July–Sept), 2014. Dust samples were analyzed for Der p 1 and Der f 1 using a two-site monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) analysis. Housing characteristics including age of home, occupant density, and age of mattresses, furniture, and carpeting were also measured. Positive Der p 1 or Der f 1 samples were found in 25.0% of the homes and there was no difference in mean allergen levels by type of air conditioning. Indoor relative humidity was significantly higher in homes with evaporative coolers compared to those with central air conditioning during the summer. Homes with evaporative coolers also spent significantly more time during summer above 55.0% and 65.0% relative humidity compared to central air homes, but not above 75.0%. Findings from this study suggest that increased humidity from evaporative coolers may not be sufficient to exceed the critical equilibrium humidity or maintain humidity excursions for sufficient duration in relatively larger single-family homes in semi-arid climates to support mite growth and reproduction. PMID:26808528

MP29-02 reduces nasal hyperreactivity and nasal mediators in patients with house dust mite-allergic rhinitis.

PubMed

Kortekaas Krohn, I; Callebaut, I; Alpizar, Y A; Steelant, B; Van Gerven, L; Skov, P S; Kasran, A; Talavera, K; Wouters, M M; Ceuppens, J L; Seys, S F; Hellings, P W

2018-05-01

Nasal hyperreactivity (NHR) is an important clinical feature of allergic rhinitis (AR). The efficacy of MP29-02 (azelastine hydrochloride (AZE) and fluticasone propionate [FP]) nasal spray on local inflammatory mediators and NHR in AR is unknown. We tested if MP29-02 decreases inflammatory mediators and NHR in AR and if this effect is due to restoration of nasal epithelial barrier function. A 4-week double-blinded placebo-controlled trial with MP29-02 treatment was conducted in 28 patients with house dust mite (HDM) AR. The presence of NHR was evaluated by measuring reduction in nasal flow upon cold dry air exposure. The effects of AZE ± FP on barrier integrity and airway inflammation were studied in a murine model of HDM-induced NHR and on reduced activation of murine sensory neurons and human mast cells. MP29-02 but not placebo reduced NHR (P < .0001 vs P = .21), levels of substance P (P = .026 vs P = .941), and β-hexosaminidase (P = .036 vs P = .632) in human nasal secretions. In wild-type C57BL6 mice, the reduction in β-hexosaminidase levels (P < .0001) by AZE + FP treatment upon HDM challenge was found in parallel with a decreased transmucosal passage (P = .0012) and completely reversed eosinophilic inflammation (P = .0013). In vitro, repeated applications of AZE + FP desensitized sensory neurons expressing the transient receptor potential channels TRPA1 and TRPV1. AZE + FP reduced MC degranulation to the same extent as AZE alone. MP29-02 treatment reduces inflammatory mediators and NHR in AR. The effects of AZE + FP on MC degranulation, nasal epithelial barrier integrity, and TRP channels provide novel insights into the pathophysiology of allergic rhinitis. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

Secretoglobin Superfamily Protein SCGB3A2 Alleviates House Dust Mite-Induced Allergic Airway Inflammation in Mice.

PubMed

Yoneda, Mitsuhiro; Xu, Lei; Kajiyama, Hiroaki; Kawabe, Shuko; Paiz, Jorge; Ward, Jerrold M; Kimura, Shioko

2016-01-01

Secretoglobin (SCGB) 3A2, a novel, lung-enriched, cytokine-like, secreted protein of small molecular weight, was demonstrated to exhibit various biological functions including anti-inflammatory, antifibrotic and growth-factor activities. Anti-inflammatory activity was uncovered using the ovalbumin-induced allergic airway inflammation model. However, further validation of this activity using knockout mice in a different allergic inflammation model is necessary in order to establish the antiallergic inflammatory role for this protein. Scgb3a2-null (Scgb3a2-/-) mice were subjected to nasal inhalation of Dermatophagoides pteronyssinus extract for 5 days/week for 5 consecutive weeks; control mice received nasal inhalation of saline as a comparator. Airway inflammation was assessed by histological analysis, the number of inflammatory cells and various Th2-type cytokine levels in the lungs and bronchoalveolar lavage fluids by qRT-PCR and ELISA, respectively. Exacerbated inflammation was found in the airway of Scgb3a2-/- mice subjected to house dust mite (HDM)-induced allergic airway inflammation compared with saline-treated control groups. All the inflammation end points were increased in the Scgb3a2-/- mice. The Ccr4 and Ccl17 mRNA levels were higher in HDM-treated lungs of Scgb3a2-/- mice than wild-type mice or saline-treated Scgb3a2-/- mice, whereas no changes were observed for Ccr3 and Ccl11 mRNA levels. These results demonstrate that SCGB3A2 has an anti-inflammatory activity in the HDM-induced allergic airway inflammation model, in which SCGB3A2 may modulate the CCR4-CCL17 pathway. SCGB3A2 may provide a useful tool to treat allergic airway inflammation, and further studies on the levels and function of SCGB3A2 in asthmatic patients are warranted. © 2016 S. Karger AG, Basel.

Lead in Chinese villager house dust: Geographical variation and influencing factors.

PubMed

Bi, Xiangyang; Liu, Jinling; Han, Zhixuan; Yang, Wenlin

2015-12-01

House dust has been recognized as an important contributor to Pb exposure of children. Here we conducted a comprehensive study to investigate geographical variation of Pb in Chinese villager house dust. The influences of outdoor soil Pb concentrations, dates of construction, house decoration materials, heating types, and site specific pollution on Pb concentrations in house dust were evaluated. The concentrations of Pb in 477 house dust samples collected from twenty eight areas throughout China varied from 12 to 2510 mg/kg, with a median concentration of 42 mg/kg. The median Pb concentrations in different geographical areas ranged from 16 (Zhangjiakou, Hebei) to 195 mg/kg (Loudi, Hunan). No correlations were found between the house dust Pb concentrations and the age of houses, as well as house decoration materials. Whereas outdoor soil, coal combustion, and site specific pollution may be potential Pb sources. Principal component analysis (PCA) confirmed that elemental compositions of the house dust were controlled by both anthropogenic and geogenic sources. Using scanning electron microscopy (SEM), the Pb bearing particles in the house dust were also studied. Copyright © 2015 Elsevier Ltd. All rights reserved.

Detailed two-dimensional gel proteomic mapping of the feces of the house dust mite Dermatophagoides pteronyssinus and comparison with D. farinae: Reduced trypsin protease content in D. pteronyssinus and different isoforms.

PubMed

Erban, Tomas; Harant, Karel; Hubert, Jan

2017-06-06

Major domestic mite allergens are present in feces. We present a detailed 2D-E-MS/MS proteomic analysis of the Dermatophagoides pteronyssinus feces. Precise cultivation yielded a pure fecal extract. We detected differences in fecal allergens/digestive enzymes between D. pteronyssinus and D. farinae using 2D-E fingerprinting, including unique information on species-specific protease isoforms. Proteomic analysis was performed by 2D-E coupled with MALDI-TOF/TOF identification. The species-specific differences in the fecal extracts of the mites were attributed to trypsin-like proteases known as group 3 allergens. In D. farinae, Der f 3 exhibited high abundance with a pI similar (acidic) to that of the cysteine protease Der f 1 and the chymotrypsin protease Der f 6, whereas in D. pteronyssinus, Der p 3 was rarely detected and exhibited low abundance only at basic pI. Moreover, Der p 9 was detected at a pI of ~ 10, in contrast to Der p 1 and Der p 6, suggesting different compartmentalization in the body. Overall, in D. pteronyssinus feces, allergens of groups 1, 2, 6, and 15 were quantitatively similar to those of D. farinae with the exception of the group 3 and 9 allergens. This work provides novel insights into mite-defecated proteins/digestive enzymes, which are important allergens. Millions of people are affected by allergy and asthma, and their number is growing. In homes, the major triggers of allergy and asthma are the house dust mites Dermatophagoides farinae and D. pteronyssinus, and a clear understanding of the development of diseases caused by these mites is needed. The major sources of mite allergens are their feces, which are deposited in the environment and are easily inhaled as part of aeroplankton. However, descriptions of and comparisons between the major fecal allergens of these two mites are lacking. This study shows that similar group 1 (cysteine protease), 2 (NPC2 family), 6 (chymotrypsin) and 15 (chitinase-like) allergens are present in the feces of

Acaricidal activities of β-caryophyllene oxide and structural analogues derived from Psidium cattleianum oil against house dust mites.

PubMed

Oh, Min-Seok; Yang, Ji-Yeon; Kim, Min-Gi; Lee, Hoi-Seon

2014-05-01

This study was to evaluate the acaricidal activities of an active compound isolated from Psidium cattleianum and structural analogues against Dermatophagoides farinae and D. pteronyssinus. β-Caryophyllene oxide was isolated using chromatographic techniques. Based on the 50% lethal concentration (LD50) values against D. farinae using the fumigant method, β-caryophyllene oxide (1.36 µg cm(-2)) was ∼ 7.52 times more toxic than benzyl benzoate (10.23 µg cm(-2)), followed by α-caryophyllene (1.75 µg cm(-2)) and β-caryophyllene (3.13 µg cm(-2)). Against D. pteronyssinus, β-caryophyllene oxide (1.38 µg cm(-2)) was ∼ 7.22 times more toxic than benzyl benzoate (9.96 µg cm(-2)), followed by α-caryophyllene (1.71 µg cm(-2)) and β-caryophyllene (3.58 µg cm(-2)). In the contact toxicity method against D. farinae, β-caryophyllene oxide (0.44 µg cm(-2)) was ∼ 17.27 times more active than benzyl benzoate (7.60 µg cm(-2)), followed by α-caryophyllene (0.67 µg cm(-2)) and β-caryophyllene (0.91 µg cm(-2)). Against D. pteronyssinus, β-caryophyllene oxide (0.47 µg cm(-2)) was ∼ 13.06 times more effective than benzyl benzoate (6.14 µg cm(-2)), followed by α-caryophyllene (1.71 µg cm(-2)) and β-caryophyllene (3.58 µg cm(-2)). β-Caryophyllene oxide and structural analogues have potential for development as preventive agents for the control of house dust mites. © 2013 Society of Chemical Industry.

Morus alba L. suppresses the development of atopic dermatitis induced by the house dust mite in NC/Nga mice

PubMed Central

2014-01-01

Background Morus alba, a medicinal plant in Asia, has been used traditionally to treat diabetes mellitus and hypoglycemia. However, the effects of M. alba extract (MAE) on atopic dermatitis have not been verified scientifically. We investigated the effects of MAE on atopic dermatitis through in vitro and in vivo experiments. Methods We evaluated the effects of MAE on the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in RAW 264.7, as well as thymus and activation-regulated chemokine (TARC/CCL17) in HaCaT cells. In an in vivo experiment, atopic dermatitis was induced by topical application of house dust mites for four weeks, and the protective effects of MAE were investigated by measuring the severity of the skin reaction on the back and ears, the plasma levels of immunoglobulin E (IgE) and histamine, and histopathological changes in the skin on the back and ears. Results MAE suppressed the production of NO and PGE2 in RAW 264.7 cells, as well as TARC in HaCaT cells, in a dose-dependent manner. MAE treatment of NC/Nga mice reduced the severity of dermatitis and the plasma levels of IgE and histamine. MAE also reduced the histological manifestations of atopic dermatitis-like skin lesions such as erosion, hyperplasia of the epidermis and dermis, and inflammatory cell infiltration in the skin on the back and ears. Conclusion Our results suggest that MAE has potent inhibitory effects on atopic dermatitis-like lesion and may be a beneficial natural resource for the treatment of atopic dermatitis. PMID:24755250

Exposure to dust mite allergen and endotoxin in early life and asthma and atopy in childhood

PubMed Central

Celedón, Juan C.; Milton, Donald K.; Ramsey, Clare D.; Litonjua, Augusto A.; Ryan, Louise; Platts-Mills, Thomas A. E.; Gold, Diane R.

2013-01-01

Background There has been no longitudinal study of the relation between concurrent exposure to dust mite allergen and endotoxin in early life and asthma and atopy at school age. Objectives To examine the relation between exposure to dust mite allergen and endotoxin at age 2 to 3 months and asthma, wheeze, and atopy in high-risk children. Methods Birth cohort study of 440 children with parental history of atopy in the Boston metropolitan area. Results In multivariate analyses, early exposure to high levels of dust mite allergen (≥10 μg/g) was associated with increased risks of asthma at age 7 years (odds ratio [OR], 3.0; 95% CI, 1.1-7.9) and late-onset wheeze (OR, 5.0; 95% CI, 1.5-16.4). Exposure to endotoxin levels above the lowest quartile at age 2 to 3 months was associated with reduced odds of atopy at school age (OR, 0.5; 95% CI, 0.2-0.9). In contrast with its inverse association with atopy, endotoxin exposure in early life was associated with an increased risk of any wheeze between ages 1 and 7 years that did not change significantly with time (hazard ratio for each quartile increment in endotoxin levels, 1.23; 95% CI, 1.07-1.43). Conclusion Among children at risk of atopy, early exposure to high levels of dust mite allergen is associated with increased risks of asthma and late-onset wheeze. In these children, endotoxin exposure is associated with a reduced risk of atopy but an increased risk of wheeze. Clinical implications Early endotoxin exposure may be a protective factor against atopy but a risk factor for wheeze in high-risk children. PMID:17507083

Activation of mas-related G-protein-coupled receptors by the house dust mite cysteine protease Der p1 provides a new mechanism linking allergy and inflammation.

PubMed

Reddy, Vemuri B; Lerner, Ethan A

2017-10-20

Cysteine and serine proteases function via protease-activated and mas-related G-protein-coupled receptors (Mrgprs) to contribute to allergy and inflammation. Der p1 is a cysteine protease and major allergen from the house dust mite and is associated with allergic rhinitis and allergic asthma. Der p1 activates protease-activated receptor 2 and induces the release of the pro-inflammatory cytokine IL-6 from cells. However, the possibility that Der p1 acts on Mrgprs has not been considered. We report here that ratiometric calcium imaging reveals that Der p1 activates the human receptor MRGPRX1 and the mouse homolog MrgprC11, implicated previously in itch. Der p1 cleavage of N-terminal receptor peptides followed by site-directed mutagenesis of the cleavage sites links receptor activation to specific amino acid residues. Der p1 also induced the release of IL-6 from heterologous cells expressing MRGPRX1. In summary, activation of Mrgprs by the allergen Der p1 may contribute to inflammation. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Clinical and immunological responses of dust mite sensitive, atopic dogs to treatment with sublingual immunotherapy (SLIT).

PubMed

DeBoer, Douglas J; Verbrugge, Maria; Morris, Mary

2016-04-01

Sublingual immunotherapy (SLIT) has been reported to be beneficial in people with atopic dermatitis (AD) and dust mite sensitivity. Evaluation of this therapy has not been reported in spontaneous canine AD. The objective of this study was to preliminarily evaluate the effectiveness of an established SLIT protocol, as used in human patients, in dogs with AD. Ten dust mite sensitive dogs with spontaneous AD. Dogs underwent a 6 month open trial of SLIT concurrently with decreasing dose oral methylprednisolone. Clinical evaluations and quantitative serum anti-mite IgE and IgG levels were performed every 2 months. Mean methylprednisolone use from the first 2 months of the study to the final 2 months declined from 10.2 to 4.3 mg/kg/2 months (P < 0.001, Student's paired t-test); at 6 months, four dogs required no oral corticosteroid administration. Over the course of the study, median Canine Atopic Dermatitis Extent and Severity Index (CADESI)-03 scores declined from 76.5 to 59; median pruritus scores declined from 65 to 37 (P < 0.02 and P < 0.01, respectively; Wilcoxon signed-rank test). Pre- and post-SLIT intradermal test scores for mite allergen were not significantly different over time. Median Dermatophagoides farinae (DF)-specific IgE levels declined significantly from 150.2 × 10(3) AU/mL to 3.6 × 10(3) AU/mL (P < 0.05). Concurrently, median DF-specific IgG levels increased from 18.5 × 10(6) AU/mL to 3923.4 × 10(6) AU/mL (P < 0.05; Wilcoxon signed-rank tests). SLIT treatment produced clinical improvement in dogs with dust mite-associated AD and was associated with serological changes supporting this improvement. Further studies in larger numbers of dogs and those with polysensitization are warranted. © 2016 ESVD and ACVD.

Bioavailability of House Dust Mite Allergens in Sublingual Allergy Tablets Is Highly Dependent on the Formulation.

PubMed

Ohashi-Doi, Katsuyo; Kito, Hirokazu; Du, Weibin; Nakazawa, Hiroshi; Ipsen, Henrik; Gudmann, Pernille; Lund, Kaare

2017-01-01

In sublingual immunotherapy (SLIT), the immune system is addressed by solubilized allergen that interacts with immunocompetent cells of the oral mucosa, the efficiency of which is governed by 2 main factors of SLIT allergen bioavailability: the allergen concentration and the mucosal contact time. Recently, 3 house dust mite (HDM) SLIT tablets were developed that differ with regard to allergen content, nominal strength (maintenance doses: 6 SQ-HDM/10,000 Japanese Allergen Units [JAU], 12 SQ-HDM/ 20,000 JAU, and 300 IR/57,000 JAU), and formulation (freeze-dried/compressed). Here, the importance of the SLIT tablet formulation for HDM major allergen bioavailability is examined. The HDM major allergen content, tablet disintegration times, and allergen release kinetics were determined. Dissolution kinetics (allergen concentration vs. time) of Der f 1, Der p 1, and Der 2 were measured. Area under the curve (AUC) was used as a surrogate parameter for allergen bioavailability. The release of HDM major allergens from the freeze-dried tablets was complete after 30 s, while only partial release was achieved with the compressed tablets, even after prolonged dissolution. At 1 min, i.e., the recommended sublingual holding time for the freeze-dried tablets, the allergen bioavailability (AUC) of the compressed 300 IR/57,000 JAU tablet was 4.7-fold (Der f 1), 10.8-fold (Der p 1), and 23.6-fold (Der 2) lower than that of the freeze-dried 12 SQ-HDM/20,000 JAU tablet and similar to (Der f 1) and 5.3-fold (Der p 1) and 12.5-fold (Der 2) lower than that of the freeze-dried 6 SQ-HDM/10,000 JAU tablet. SLIT tablet allergen bioavailability depends highly on the tablet formulation. Only the fast-dissolving freeze-dried tablets provide maximal delivery of soluble allergens and achieve allergen concentrations that reflect the nominal tablet strengths within the recommended sublingual holding time. © 2017 S. Karger AG, Basel.

House dust mite-induced asthma causes oxidative damage and DNA double-strand breaks in the lungs.

PubMed

Chan, Tze Khee; Loh, Xin Yi; Peh, Hong Yong; Tan, W N Felicia; Tan, W S Daniel; Li, Na; Tay, Ian J J; Wong, W S Fred; Engelward, Bevin P

2016-07-01

Asthma is related to airway inflammation and oxidative stress. High levels of reactive oxygen and nitrogen species can induce cytotoxic DNA damage. Nevertheless, little is known about the possible role of allergen-induced DNA damage and DNA repair as modulators of asthma-associated pathology. We sought to study DNA damage and DNA damage responses induced by house dust mite (HDM) in vivo and in vitro. We measured DNA double-strand breaks (DSBs), DNA repair proteins, and apoptosis in an HDM-induced allergic asthma model and in lung samples from asthmatic patients. To study DNA repair, we treated mice with the DSB repair inhibitor NU7441. To study the direct DNA-damaging effect of HDM on human bronchial epithelial cells, we exposed BEAS-2B cells to HDM and measured DNA damage and reactive oxygen species levels. HDM challenge increased lung levels of oxidative damage to proteins (3-nitrotyrosine), lipids (8-isoprostane), and nucleic acid (8-oxoguanine). Immunohistochemical evidence for HDM-induced DNA DSBs was revealed by increased levels of the DSB marker γ Histone 2AX (H2AX) foci in bronchial epithelium. BEAS-2B cells exposed to HDM showed enhanced DNA damage, as measured by using the comet assay and γH2AX staining. In lung tissue from human patients with asthma, we observed increased levels of DNA repair proteins and apoptosis, as shown by caspase-3 cleavage, caspase-activated DNase levels, and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining. Notably, NU7441 augmented DNA damage and cytokine production in the bronchial epithelium and apoptosis in the allergic airway, implicating DSBs as an underlying driver of asthma pathophysiology. This work calls attention to reactive oxygen and nitrogen species and HDM-induced cytotoxicity and to a potential role for DNA repair as a modulator of asthma-associated pathophysiology. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Seasonal and occupational trends of five organophosphate pesticides in house dust.

PubMed

Smith, Marissa N; Workman, Tomomi; McDonald, Katie M; Vredevoogd, Melinda A; Vigoren, Eric M; Griffith, William C; Thompson, Beti; Coronado, Gloria D; Barr, Dana; Faustman, Elaine M

2017-07-01

Since 1998, the University of Washington's Center for Child Environmental Health Risks Research has followed a community-based participatory research strategy in the Lower Yakima Valley of Washington State to assess pesticide exposure among families of Hispanic farmworkers. As a part of this longitudinal study, house dust samples were collected from both farmworker and non-farmworker households, across three agricultural seasons (thinning, harvest and non-spray). The household dust samples were analyzed for five organophosphate pesticides: azinphos-methyl, phosmet, malathion, diazinon, and chlorpyrifos. Organophosphate pesticide levels in house dust were generally reflective of annual use rates and varied by occupational status and agricultural season. Overall, organophosphate pesticide concentrations were higher in the thinning and harvest seasons than in the non-spray season. Azinphos-methyl was found in the highest concentrations across all seasons and occupations. Farmworker house dust had between 5- and 9-fold higher concentrations of azinphos-methyl than non-farmworker house dust. Phosmet was found in 5-7-fold higher concentrations in farmworker house dust relative to non-farmworker house dust. Malathion and chlorpyriphos concentrations in farmworker house dust ranged between 1.8- and 9.8-fold higher than non-farmworker house dust. Diazinon showed a defined seasonal pattern that peaked in the harvest season and did not significantly differ between farmworker and non-farmworker house dust. The observed occupational differences in four out of five of the pesticide residues measured provides evidence supporting an occupational take home pathway, in which workers may bring pesticides home on their skin or clothing. Further, these results demonstrate the ability of dust samples to inform the episodic nature of organophosphate pesticide exposures and the need to collect multiple samples for complete characterization of exposure potential.

Involvement of the mannose receptor in the uptake of Der p 1, a major mite allergen, by human dendritic cells.

PubMed

Deslée, Gaëtan; Charbonnier, Anne-Sophie; Hammad, Hamida; Angyalosi, Gerhild; Tillie-Leblond, Isabelle; Mantovani, Alberto; Tonnel, André-Bernard; Pestel, Joël

2002-11-01

Immature dendritic cells (DCs) take up antigens in peripheral tissues and, after antigen processing, mature to efficiently stimulate T cells in secondary lymph nodes. In allergic airway diseases DCs have been shown to be involved in the induction and maintenance of a T(H)2-type profile. The present study was undertaken to determine pathways of Der p 1 (a house dust mite allergen) uptake by human DCs and to compare Der p 1 uptake between DCs from patients with house dust mite allergy and DCs from healthy donors. Monocyte-derived DCs (MD-DCs) were obtained from patients with house dust mite allergy (n = 13) and healthy donors (n = 11). Der p 1 was labeled with rhodamine. Der p 1 uptake by MD-DCs was analyzed by means of flow cytometry and confocal microscopy. Rhodamine- labeled Der p 1 was demonstrated to be taken up by MD-DCs in a dose-, time-, and temperature- dependent manner. The involvement of the mannose receptor (MR) in the Der p 1 uptake was demonstrated by using (1) inhibitors of the MR- mediated endocytosis (mannan and blocking anti-MR mAb), which inhibited the Der p 1 uptake from 40 % to 50 %, and (2) confocal microscopy showing the colocalization of rhodamine-labeled Der p 1 with FITC-dextran. Interestingly, compared with DCs from healthy donors, DCs from allergic patients expressed more MR and were more efficient in Der p 1 uptake. These results suggest that the MR could play a key role in the Der p 1 allergen uptake by DCs and in the pathogenesis of allergic diseases in dust mite -sensitive patients.

Effect of bedding control on amount of house dust mite allergens, asthma symptoms, and peak expiratory flow rate.

PubMed

Lee, Inn-Sook

2003-04-30

This quasi-experimental study was designed to investigate the effect of bedding control on the amount of house dust mite (HDM) allergens, asthma symptoms, and peak expiratory flow rate (PEFR) in asthmatics sensitive to HDMs. The subjects in the study were drawn from patients receiving treatment at the allergy clinics of three university-affiliated hospitals in Seoul. Forty-two patients without prior practice of the bedding control used in this study were selected. They commonly showed bronchial asthma caused by HDMs, and exhibited strong positive points (more than 3 points) in skin prick test (D. farinae, D. pteronyssinus), and positive response in both fluoro-allergosorbent test (FAST), and PC20 methacholine test. Of the subjects, alternatively, 22 were assigned to the experimental group and 20 to control group. Bedding control consisted of the use of outer cotton covers, boiling them for 10 minutes fortnightly, and disinfecting bedding by sunlight fortnightly. The experimental group was under bedding control for 4 weeks. The data were collected from October 2000 to January 2001. The results were as follows: 1. After bedding control, the total amount of HDM allergens decreased significantly in the experimental group. However there was no significant difference in the decrease of the amount of HDM allergens between the two groups. 2. Of the asthma symptoms, there was significant difference only in the decrease of the frequency of dyspnea, and in the increase of sleeping disturbance between the two groups after bedding control. 3. After bedding control, PEFR increased in the experimental group whereas it decreased in the control group. However, neither change was significant. The above findings indicate that bedding control improved several asthma symptoms in asthmatics sensitive to HDMs. Accordingly, we suggest that bedding control is adopted as a useful nursing intervention in the field.

Sensitization by subcutaneous route is superior to intraperitoneal route in induction of asthma by house dust mite in a murine mode

PubMed Central

Aun, Marcelo Vivolo; Saraiva-Romanholo, Beatriz Mangueira; de Almeida, Francine Maria; Brüggemann, Thayse Regina; Kalil, Jorge; Martins, Milton de Arruda; Arantes-Costa, Fernanda Magalhães; Giavina-Bianchi, Pedro

2015-01-01

ABSTRACT Objective To develop a new experimental model of chronic allergic pulmonary disease induced by house dust mite, with marked production of specific immunoglobulin E (IgE), eosinophilic inflammatory infiltrate in the airways and remodeling, comparing two different routes of sensitization. Methods The protocol lasted 30 days. BALB/c mice were divided into six groups and were sensitized subcutaneously or intraperitoneally with saline (negative control), Dermatophagoides pteronyssinus (Der p) 50 or 500mcg in three injections. Subsequently they underwent intranasal challenge with Der p or saline for 7 days and were sacrificed 24 hours after the last challenge. We evaluated the titration of specific IgE anti-Der p, eosinophilic density in peribronchovascular space and airway remodeling. Results Both animals sensitized intraperitoneally and subcutaneously produced specific IgE anti-Der p. Peribronchovascular eosinophilia increased only in mice receiving lower doses of Der p. However, only the group sensitized with Der p 50mcg through subcutaneously route showed significant airway remodeling. Conclusion In this murine model of asthma, both pathways of sensitization led to the production of specific IgE and eosinophilia in the airways. However, only the subcutaneously route was able to induce remodeling. Furthermore, lower doses of Der p used in sensitization were better than higher ones, suggesting immune tolerance. Further studies are required to evaluate the efficacy of this model in the development of bronchial hyperresponsiveness, but it can already be replicated in experiments to create new therapeutic drugs or immunotherapeutic strategies. PMID:26761554

Changes in skin reactivity and associated factors in patients sensitized to house dust mites after 1 year of allergen-specific immunotherapy.

PubMed

Son, Jeong-Yeop; Jung, Mann-Hong; Koh, Kwang-Wook; Park, Eun-Kee; Heo, Jeong-Hoon; Choi, Gil-Soon; Kim, Hee-Kyoo

2017-04-01

Allergen-specific immunotherapy (SIT) can significantly improve symptoms and reduce the need for symptomatic medication. The aim of this study was to investigate changes in skin reactivity to house dust mites (HDMs) as an immunologic response and associated factors after 1 year of immunotherapy. A total of 80 patients with allergic airway diseases who received subcutaneous SIT with HDMs from 2009 to 2014 were evaluated. The investigated parameters were basic demographic characteristics, skin reactivity and specific IgE for HDM, serum total IgE level, blood eosinophil counts, and medication score. The mean levels of skin reactivity to HDMs, blood eosinophil counts, and medication scores after 1 year were significantly reduced from baseline. In univariate comparison of the changes in skin reactivity to HDMs, age ≤30 years, HDMs only as target of immunotherapy, and high initial skin reactivity (≥2) to HDMs were significantly associated with the reduction in skin test reactivity. In multivariate analysis, high initial skin reactivity and HDMs only as target allergens were significantly associated with changes in skin reactivity to HDMs. In the receiver operating characteristic curve of the initial mean skin reactivity to HDMs for more than 50% reduction, the optimal cutoff value was 2.14. This study showed significant reductions in allergen skin reactivity to HDMs after 1 year of immunotherapy in patients sensitized to HDMs. The extent of initial allergen skin reactivity and only HDMs as target allergen were important predictive factors for changes in skin reactivity.

Comparison between Siriraj mite allergen vaccine and standardized commercial mite vaccine by skin prick testing in normal Thai adults.

PubMed

Visitsunthorn, Nualanong; Pacharn, Punchama; Jirapongsananuruk, Orathai; Weeravejsukit, Sirirat; Sripramong, Chaweewan; Sookrung, Nitat; Bunnag, Chaweewan

2010-03-01

House dust mite is a major cause of allergic asthma and rhinitis in Thai population. Skin prick test (SPT) is a useful tool for the diagnosis of the IgE-mediated reactions. The imported commercial mite vaccine for SPT is available but it is relatively expensive. Aim of this study is to compare Siriraj Mite Allergen Vaccine (SMAV) with standardized commercial mite allergen vaccine by skin prick testing in normal Thai adults. A double blind, self-controlled study between the SMAV and standardized commercial mite allergen vaccine was performed by SPT in 17 normal Thai adult males and non-pregnant or non-lactating females aged 18-60 years. The study showed that 35.29 % of non atopic adults had positive SPT reaction to Dp and Df of both SMAV and standardized commercial mite allergen vaccine. Mean wheal and flare diameters from SPT of Dp and Df of SMAV showed strong correlation with standardized commercial mite allergen vaccine (r= 0.768 and 0.897 in Dp and Df respectively, p <0.001). The intraclass correlation was also excellent (0.893 and 0.775 in Dp and Df respectively). There was no significant difference in wheal and flare diameter between SMAV and standardized commercial mite allergen vaccine. No systemic or large local reaction was found in any of the study cases.

Association between KIR genes and dust mite sensitization in a Brazilian population.

PubMed

Caniatti, Marcela Caleffi da Costa Lima; Borelli, Sueli Donizete; Guilherme, Ana Lúcia Falavigna; Franzener, Soraya Barrionuevo; Tsuneto, Luiza Tamie

2018-01-01

Killer cell immunoglobulin-like receptors (KIRs), found on the surface of natural killer (NK) cells, play a key role in controlling the innate response. Such response depends on a series of cellular interactions between these receptors and HLA activating/inhibiting ligands. Atopic diseases have been associated with genes that regulate cytokine production and HLA genes, which may either protect or predispose to hypersensitivity. To verify an association study of KIR genes with sensitization to the following mites: Dermatophagoides farinae, Dermatophagoides pteronyssinus, and Blomia tropicalis. A total of 341 children aged up to 14 years, were classified as mite-sensitive or mite-insensitive after undergoing a skin prick test for immediate allergic reactions. The presence/absence of KIR genes and their human leukocyte antigen (HLA) ligands was determined by polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO) with the commercial kit LabType™ using Luminex™. The frequencies of KIR genes and their respective class I HLA ligands and the frequency of haplotypes were performed in sensitive and insensitive individuals, and no significant differences were found. Our results suggest no influence of KIR genes on resistance/susceptibility to sensitization to dust mites. Copyright © 2017 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Exposure to microbial components and allergens in population studies: a comparison of two house dust collection methods applied by participants and fieldworkers.

PubMed

Schram-Bijkerk, D; Doekes, G; Boeve, M; Douwes, J; Riedler, J; Ublagger, E; von Mutius, E; Benz, M; Pershagen, G; Wickman, M; Alfvén, T; Braun-Fahrländer, C; Waser, M; Brunekreef, B

2006-12-01

Dust collection by study participants instead of fieldworkers would be a practical and cost-effective alternative in large-scale population studies estimating exposure to indoor allergens and microbial agents. We aimed to compare dust weights and biological agent levels in house dust samples taken by study participants with nylon socks, with those in samples taken by fieldworkers using the sampling nozzle of the Allergology Laboratory Copenhagen (ALK). In homes of 216 children, parents and fieldworkers collected house dust within the same year. Dust samples were analyzed for levels of allergens, endotoxin, (1-->3)-beta-D-glucans and fungal extracellular polysaccharides (EPS). Socks appeared to yield less dust from mattresses at relatively low dust amounts and more dust at high dust amounts than ALK samples. Correlations between the methods ranged from 0.47-0.64 for microbial agents and 0.64-0.87 for mite and pet allergens. Cat allergen levels were two-fold lower and endotoxin levels three-fold higher in socks than in ALK samples. Levels of allergens and microbial agents in sock samples taken by study participants are moderately to highly correlated to levels in ALK samples taken by fieldworkers. Absolute levels may differ, probably because of differences in the method rather than in the person who performed the sampling. Practical Implications Dust collection by participants is a reliable and practical option for allergen and microbial agent exposure assessment. Absolute levels of biological agents are not (always) comparable between studies using different dust collection methods, even when expressed per gram dust, because of potential differences in particle-size constitution of the collected dust.

Saussurea lappa alleviates inflammatory chemokine production in HaCaT cells and house dust mite-induced atopic-like dermatitis in Nc/Nga mice.

PubMed

Lim, Hye-Sun; Ha, Hyekyung; Lee, Mee-Young; Jin, Seong-Eun; Jeong, Soo-Jin; Jeon, Woo-Young; Shin, Na-Ra; Sok, Dai-Eun; Shin, Hyeun-Kyoo

2014-01-01

Saussurea lappa is a traditional herbal medicine used for to treat various inflammatory diseases. In this study, we investigated the protective effects of S. lappa against atopic dermatitis using human keratinocyte HaCaT cells, murine mast cell line MC/9 cells, and a house dust mite-induced atopic dermatitis model of Nc/Nga mice. Treatment with the S. lappa caused a significant reduction in the mRNA levels and production of inflammatory chemokines and cytokine, including thymus- and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), regulated on activation, normal T-cell expressed and secreted (RANTES), and interleukin-8 (IL-8) in tumor necrosis factor-α/interferone-γ-stimulated HaCaT cells. S. lappa exhibited the significant reduction in histamine production in MC/9 cells. In the atopic dermatitis model, S. lappa significantly reduced the dermatitis score and serum IgE and TARC levels. In addition, the back skin and ears of S. lappa-treated Nc/Nga mice exhibited reduced histological manifestations of atopic skin lesions such as erosion, hyperplasia of the epidermis and dermis, and inflammatory cell infiltration. In conclusion, an extract of S. lappa effectively suppressed the development of atopic dermatitis, which was closely related to the reduction of chemokines and cytokine. Our study suggests that S. lappa may be a potential treatment for atopic dermatitis. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Non-targeted screening of house dust samples using accurate mass TOFMS

EPA Science Inventory

House dust exists as an environmental repository of chemicals to which we are exposed in our homes. A growing number of studies have targeted select persistent organic and inorganic pollutants found in house dust. Many have concluded that dust exists as an important human expos...

Housing and dustbathing effects on northern fowl mites (Ornithonyssus sylviarum) and chicken body lice (Menacanthus stramineus) on hens.

PubMed

Martin, C D; Mullens, B A

2012-09-01

Hen housing (cage or cage-free) did not impact overall abundances of northern fowl mites, Ornithonyssus sylviarum (Canestrini & Fanzago) (Acari: Macronyssidae), or chicken body lice, Menacanthus stramineus (Nitzsch) (Phthiraptera: Menoponidae). Cage-free hens received a dustbox with sand plus diatomaceous earth (DE), kaolin clay or sulphur. Weekly use varied from none to 100% of hens; 73% of hens used the dustbox at least once. Ectoparasite populations on dustbathing hens (users) were compared with those on non-user cage-free and caged hens. All materials reduced ectoparasites on user hens by 80-100% after 1 week of dustbox use. Diatomaceous earth and kaolin failed to reduce ectoparasites on non-user hens, and ectoparasites on user hens recovered after dustbox removal. A sulphur dustbox eliminated mites from all hens (including non-users) within 2-4 weeks. Residual sulphur controlled mites until the end of the experiment (up to 9 weeks), even after the dustbox was removed. Louse populations on hens using the sulphur dustbox were reduced in 1-2 weeks. Residual sulphur effects were less evident in lice, but the use of a sulphur dustbox by a higher proportion of hens extended louse control to all hens. This is the first experimental study to show that bird dustbathing in naturally and widely available dust materials (particularly kaolin) can suppress ectoparasites and thus the behaviour is probably adaptive. © 2012 The Authors. Medical and Veterinary Entomology © 2012 The Royal Entomological Society.

Evaluation of autologous serum skin test and skin prick test reactivity to house dust mite in patients with chronic spontaneous urticaria.

PubMed

Song, Zhiqiang; Zhai, Zhifang; Zhong, Hua; Zhou, Ziyuan; Chen, WenChieh; Hao, Fei

2013-01-01

Chronic spontaneous urticaria (CSU) is a common skin disorder with etiology that is not well understood. In this study, we evaluated the prevalence of autologous serum skin test (ASST) and skin prick testing (SPT) to house dust mite (HDM) in 862 CSU cases in China. Clinical features, courses and treatment responses were also recorded. The prevalence of positive ASST was 46.3%, and patients aged 30-39 years had the highest positive rate (52.1%). Positive SPT to HDM was seen in 153 patients (17.7%) with the highest positive rate (34.2%) in patients aged 20 or less. Patients with positive ASST had higher urticaria activity scores (UAS) (4.18±0.65 vs. 3.67±0.53) but lower positive rates of HDM (24.6% vs. 37.6%), as compared with those with negative ASST (odds ratio (OR) 1.84, 95% CI 1.38-2.47). Patients could be categorized into four groups based on the results of ASST and SPT to HDM and patients with positive ASST and positive SPT to HDM had the highest disease activity scores, experienced higher frequencies of angioedema, diseases duration, and required higher dosage of loratadine every month, compared with other subgroups (P<0.0001). Patients with CSU showed varied responses of positive ASST and varied sensitivity to HDM, Patients with positive ASST and/or positive SPT had more disease activity compared with patients with negative ASST and/or negative SPT. Further classification can be made based on the result of SPT and ASST.

Evaluation of Autologous Serum Skin Test and Skin Prick Test Reactivity to House Dust Mite in Patients with Chronic Spontaneous Urticaria

PubMed Central

Song, Zhiqiang; Zhai, Zhifang; Zhong, Hua; Zhou, Ziyuan; Chen, WenChieh; Hao, Fei

2013-01-01

Background Chronic spontaneous urticaria (CSU) is a common skin disorder with etiology that is not well understood. Methods In this study, we evaluated the prevalence of autologous serum skin test (ASST) and skin prick testing (SPT) to house dust mite (HDM) in 862 CSU cases in China. Clinical features, courses and treatment responses were also recorded. Results The prevalence of positive ASST was 46.3%, and patients aged 30–39 years had the highest positive rate (52.1%). Positive SPT to HDM was seen in 153 patients (17.7%) with the highest positive rate (34.2%) in patients aged 20 or less. Patients with positive ASST had higher urticaria activity scores (UAS) (4.18±0.65 vs. 3.67±0.53) but lower positive rates of HDM (24.6% vs. 37.6%), as compared with those with negative ASST (odds ratio (OR) 1.84, 95% CI 1.38–2.47). Patients could be categorized into four groups based on the results of ASST and SPT to HDM and patients with positive ASST and positive SPT to HDM had the highest disease activity scores, experienced higher frequencies of angioedema, diseases duration, and required higher dosage of loratadine every month, compared with other subgroups (P<0.0001). Conclusions Patients with CSU showed varied responses of positive ASST and varied sensitivity to HDM, Patients with positive ASST and/or positive SPT had more disease activity compared with patients with negative ASST and/or negative SPT. Further classification can be made based on the result of SPT and ASST. PMID:23741306

House dust in seven Danish offices

NASA Astrophysics Data System (ADS)

Mølhave, L.; Schneider, T.; Kjærgaard, S. K.; Larsen, L.; Norn, S.; Jørgensen, O.

Floor dust from Danish offices was collected and analyzed. The dust was to be used in an exposure experiment. The dust was analyzed to show the composition of the dust which can be a source of airborne dust indoors. About 11 kg of dust from vacuum cleaner bags from seven Danish office buildings with about 1047 occupants (12 751 m 2) was processed according to a standardized procedure yielding 5.5 kg of processed bulk dust. The bulk dust contained 130.000-160.000 CFU g -1 microorganisms and 71.000-90.000 CFU g -1 microfungi. The content of culturable microfungi was 65-123 CFU 30 g -1 dust. The content of endotoxins ranged from 5.06-7.24 EU g -1 (1.45 ng g -1 to 1.01 ng g -1). Allergens (ng g -1) were from 147-159 (Mite), 395-746 (dog) and 103-330 (cat). The macro molecular organic compounds (the MOD-content) varied from 7.8-9.8 mg g -1. The threshold of release of histamine from basophil leukocytes provoked by the bulk dust was between 0.3 and 1.0 mg ml -1. The water content was 2% (WGT) and the organic fraction 33%. 6.5-5.9% (dry) was water soluble. The fiber content was less than 0.2-1.5% (WGT) and the desorbable VOCs was 176-319 μg g -1. Most of the VOC were aldehydes. However, softeners for plastic (DBP and DEHP) were present. The chemical composition includes human and animal skin fragments, paper fibers, glass wool, wood and textilefibers and inorganic and metal particles. The sizes ranged from 0.001-1 mm and the average specific density was 1.0 g m -3. The bulk dust was resuspended and injected into an exposure chamber. The airborne dust was sampled and analyzed to illustrate the exposures that can result from sedimented dirt and dust. The airborne dust resulting from the bulk dust reached concentrations ranging from 0.26-0.75 mg m -3 in average contained 300-170 CFU m -3. The organic fraction was from 55-70% and the water content about 2.5% (WGT). The content of the dust was compared to the similar results reported in the literature and its toxic potency is

Mite and pet allergen exposure in hotels in Uberlândia, Midwestern Brazil.

PubMed

Simplício, E C; Silva, D A O; Braga, I A; Sopelete, M C; Sung, S J; Taketomi, E A

2007-08-01

Mite allergens are involved in airway sensitization and allergic diseases. We evaluated the exposure to house dust-mite (Der p 1 and Der f 1) and pet (Fel d 1 and Can f 1) allergens in hotels in Uberlândia, Midwestern Brazil. A total of 140 dust samples were collected from bedding (n = 98) and carpet (n = 42) of bedrooms in 20 hotels enrolled for this study. Geometric mean (GM) levels of Der f 1 (11.30 microg/g of dust; 95% CI: 8.34-15.30 microg/g) were significantly higher than Der p 1 (0.15 microg/g of dust; 95% CI: 0.13-0.18 microg/g) in bedding dust samples (P < 0.001), regardless of the hotel classes. Der f 1 levels were significantly higher in bedding (11.30 microg/g of dust; 95% CI: 8.34-15.30 microg/g) than carpet (6.32 microg/g of dust; 95% CI: 4.31-9.26 microg/g) dust samples (P < 0.05). High levels of Der f 1 (>10 microg/g of dust) were found in 58%, 76%, and 69% of dust samples from Simple, Economical, and Tourist/Superior hotels, respectively, while GM levels of Fel d 1 (0.11 microg/g of dust; 95% CI: 0.09-0.14 microg/g) and Can f 1 (0.30 microg/g of dust; 95% CI: 0.20-0.44 microg/g) were relatively low. These results indicate that Der f 1 is the predominant allergen in hotels in Uberlândia, especially in bedding dust samples, regardless of the hotel classes and could represent an important risk factor for exacerbation of allergic symptoms in previously mite-sensitized guests. Mites and pets are important sources of indoor allergens. Most people spend the greatest part of their time indoors. Hotels can constitute an important allergen reservoir of the indoor environment and could represent an important risk for exacerbation of allergic symptoms in previously sensitized guests. Thus, hotels should also be included for planning indoor allergen avoidance as part of a global management strategy, especially in patients with respiratory allergy.

Safety and immunogenicity of a cluster specific immunotherapy in children with bronchial asthma and mite allergy.

PubMed

Schubert, R; Eickmeier, O; Garn, H; Baer, P C; Mueller, T; Schulze, J; Rose, M A; Rosewich, M; Renz, H; Zielen, S

2009-01-01

Cluster specific immunotherapy (SIT) is a modern form of allergen immunotherapy allowing safe administration of high allergen doses in a short time interval compared to classic SIT. In the current study, we investigated the safety profile and immunological effect of cluster SIT in children with allergic asthma due to house dust mite allergy. A total of 34 children (6-18 years) with allergic asthma were assigned to cluster (n = 22) or classic SIT (n = 12). To achieve a maintenance dose of allergen extract, cluster patients received 14 injections of house dust mite allergen within 6 weeks, whereas the classic SIT group received 14 injections within 14 weeks. Safety was monitored by recording adverse events. Immunogenicity was measured by specific IgG(Mite) and IgG4(Mite), by antibody-blocking properties on basophil activation, and by the T cell subset transcription factors Foxp3, T-bet, and GATA-3. There were no significant differences in local and systemic side effects between the two groups. In the cluster group, serum levels of specific IgG(Mite) (p < 0.001) and specific IgG4(Mite) (p < 0.001) significantly increased after 8 weeks, while it took 12 weeks in the classic SIT group. These data were confirmed by blocking CD63 expression as well as release of cysteinyl leukotrienes after in vitro basophil stimulation. No differences in transcription factor expression were found in the two groups. Cluster SIT is safe in children. Additionally, our data demonstrated an even more rapid induction of specific immune tolerance. Cluster SIT is an attractive alternative to conventional up-dosing schedules with fewer consultations for the patients. (c) 2008 S. Karger AG, Basel.

High Degree of Overlap between Responses to a Virus and to the House Dust Mite Allergen in Airway Epithelial Cells

PubMed Central

Golebski, Korneliusz; Luiten, Silvia; van Egmond, Danielle; de Groot, Esther; Röschmann, Kristina Irene Lisolette; Fokkens, Wytske Johanna; van Drunen, Cornelis Maria

2014-01-01

Background Airway epithelium is widely considered to play an active role in immune responses through its ability to detect changes in the environment and to generate a microenvironment for immune competent cells. Therefore, besides its role as a physical barrier, epithelium affects the outcome of the immune response by the production of various pro-inflammatory mediators. Methods We stimulated airway epithelial cells with viral double stranded RNA analogue poly(I:C) or with house dust mite in a time course of 24 hours. In order to determine cytokines production by stimulated cells, we performed multiplex enzyme linked immunosorbant assay (ELISA). Results We demonstrate that the temporal pattern of the genes that respond to virus exposure in airway epithelium resembles to a significant degree their pattern of response to HDM. The gene expression pattern of EGR1, DUSP1, FOSL1, JUN, MYC, and IL6 is rather similar after viral (poly(I:C)) and HDM exposure. However, both triggers also induce a specific response (e.g. ATF3, FOS, and NFKB1). We confirmed these data by showing that epithelial cells produce a variety of similar mediators in response to both poly(I:C) and HDM challenge (IL1-RA, IL-17, IFN-α and MIP1-α), sometimes with a quantitative difference in response (IL2-R, IL-6, IL-8, MCP-1, MIG, and HGF). Interestingly, only four mediators (IL-12, IP-10, RANTES and VEGF) where up-regulated specifically by poly(I:C) and not by HDM. Additionally, we report that pre-exposure to HDM deregulates production of cytokines and mediators in response to poly(I:C). Conclusions Epithelial cells responses to the HDM-allergen and a virus strongly resemble both in gene expression and in protein level explaining why these two responses may affect each other. PMID:24498371

High degree of overlap between responses to a virus and to the house dust mite allergen in airway epithelial cells.

PubMed

Golebski, Korneliusz; Luiten, Silvia; van Egmond, Danielle; de Groot, Esther; Röschmann, Kristina Irene Lisolette; Fokkens, Wytske Johanna; van Drunen, Cornelis Maria

2014-01-01

Airway epithelium is widely considered to play an active role in immune responses through its ability to detect changes in the environment and to generate a microenvironment for immune competent cells. Therefore, besides its role as a physical barrier, epithelium affects the outcome of the immune response by the production of various pro-inflammatory mediators. We stimulated airway epithelial cells with viral double stranded RNA analogue poly(I:C) or with house dust mite in a time course of 24 hours. In order to determine cytokines production by stimulated cells, we performed multiplex enzyme linked immunosorbant assay (ELISA). We demonstrate that the temporal pattern of the genes that respond to virus exposure in airway epithelium resembles to a significant degree their pattern of response to HDM. The gene expression pattern of EGR1, DUSP1, FOSL1, JUN, MYC, and IL6 is rather similar after viral (poly(I:C)) and HDM exposure. However, both triggers also induce a specific response (e.g. ATF3, FOS, and NFKB1). We confirmed these data by showing that epithelial cells produce a variety of similar mediators in response to both poly(I:C) and HDM challenge (IL1-RA, IL-17, IFN-α and MIP1-α), sometimes with a quantitative difference in response (IL2-R, IL-6, IL-8, MCP-1, MIG, and HGF). Interestingly, only four mediators (IL-12, IP-10, RANTES and VEGF) where up-regulated specifically by poly(I:C) and not by HDM. Additionally, we report that pre-exposure to HDM deregulates production of cytokines and mediators in response to poly(I:C). Epithelial cells responses to the HDM-allergen and a virus strongly resemble both in gene expression and in protein level explaining why these two responses may affect each other.

Close Positive Correlation between the Lymphocyte Response to Hen Egg White and House Dust Mites in Infants with Atopic Dermatitis.

PubMed

Kimura, Mitsuaki; Meguro, Takaaki; Ito, Yasunori; Tokunaga, Fumika; Hashiguchi, Akihiko; Seto, Shiro

2015-01-01

It was recently hypothesized that food allergens sensitize infants with atopic dermatitis (AD) via the skin. If this is the case, an intimate positive correlation should be observed between immune responses to both food and indoor allergens. One hundred and seven infants with AD and 32 controls were enrolled. The proliferation of lymphocytes stimulated with hen egg white (EW) or house dust mite (HDM) allergens was measured by means of an allergen-specific lymphocyte stimulation test (ALST). Cytokine production was measured in 13 patients and 4 controls. ALST responses for EW (EW-ALST) were significantly higher in AD infants than in control subjects (stimulation index: 7.98 vs. 2.54, p < 0.0001). HDM-ALST responses were also significantly higher in AD infants than in controls (stimulation index: 5.09 vs. 1.44, p < 0.0001). A significant positive correlation was seen between HDM-ALST and EW-ALST responses in AD infants aged 5-6 months (rs = 0.77, p < 0.000001). Serum levels of EW-specific IgE (EW-IgE) were significantly correlated with both EW-ALST (rs = 0.43, p < 0.05) and HDM-ALST levels (rs = 0.47, p < 0.05) in AD patients aged 3-4 months. Serum EW-IgE levels in AD infants were significantly correlated with the ratio of IL-4/IFN-γ production from lymphocytes stimulated with EW (rs = 0.62, p < 0.01) and with HDM (rs = 0.67, p < 0.005). This study describes the close positive correlation between EW- and HDM-specific immune responses in infants with AD. These results may support the hypothesis that both food and indoor allergens concurrently sensitize infants via the skin. © 2015 S. Karger AG, Basel.

Comparison of atopy patch testing to skin prick testing for diagnosing mite-induced atopic dermatitis: a systematic review and meta-analysis.

PubMed

Liu, Yumei; Peng, Jianglong; Zhou, Ying; Cui, Yubao

2017-01-01

Atopic dermatitis (AD) can occur after contact with aeroallergens like house dust mites, pollen, and animal dander. Despite its controversial diagnostic value, the atopy patch test (APT) has been used as an important tool in the diagnosis of AD caused by house dust mites. Here, we present a meta-analysis comparing APT to the common skin prick test (SPT) in the diagnosis of mite-induced AD. A structured search was performed using online databases and bibliographies published as of April 30, 2017. All studies evaluating the accuracy of APT and SPT in the diagnosis of mite-induced atopic eczema/dermatitis syndrome were selected, appraised, and data was extracted. Ten studies were identified for inclusion in our analysis. Meta-analysis revealed that the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios for APT were 0.54 (95% CI 0.42-0.66), 0.72 (95% CI 0.56-0.85), 1.97 (95% CI 1.20-3.23), 0.63 (95% CI 0.48-0.83), and 3.12 (95% CI 1.53-6.39). The area under the summary receiver operating characteristic curve was 0.65 (95% CI 0.61-0.69). Our analysis indicates that APT is a useful tool in the screening of mite-induced AD, although this conclusion must be interpreted cautiously due to high heterogeneity among the included studies.

Evolution of efficient methods to sample lead sources, such as house dust and hand dust, in the homes of children

DOE Office of Scientific and Technical Information (OSTI.GOV)

Que Hee, S.S.; Peace, B.; Clark, C.S.

Efficient sampling methods to recover lead-containing house dust and hand dust have been evolved so that sufficient lead is collected for analysis and to ensure that correlational analyses linking these two parameters to blood lead are not dependent on the efficiency of sampling. Precise collection of loose house dust from a 1-unit area (484 cmS) with a Tygon or stainless steel sampling tube connected to a portable sampling pump (1.2 to 2.5 liters/min) required repetitive sampling (three times). The Tygon tube sampling technique for loose house dust <177 m in diameter was around 72% efficient with respect to dust weightmore » and lead collection. A representative house dust contained 81% of its total weight in this fraction. A single handwipe for applied loose hand dust was not acceptably efficient or precise, and at least three wipes were necessary to achieve recoveries of >80% of the lead applied. House dusts of different particle sizes <246 m adhered equally well to hands. Analysis of lead-containing material usually required at least three digestions/decantations using hot plate or microwave techniques to allow at least 90% of the lead to be recovered. It was recommended that other investigators validate their handwiping, house dust sampling, and digestion techniques to facilitate comparison of results across studies. The final methodology for the Cincinnati longitudinal study was three sampling passes for surface dust using a stainless steel sampling tube; three microwave digestion/decantations for analysis of dust and paint; and three wipes with handwipes with one digestion/decantation for the analysis of six handwipes together.« less

Pathways of airway oxidant formation by house dust mite allergens and viral RNA converge through myosin motors, pannexons and Toll-like receptor 4.

PubMed

Zhang, Jihui; Chen, Jie; Mangat, Shannon C; Perera Baruhupolage, Chathuri; Garrod, David R; Robinson, Clive

2018-06-01

Intracellular reactive oxidant species (ROS) are generated in human airway epithelial cells by the prothrombinase action of Group 1 house dust mite (HDM) allergens and by ligation of viral RNA sensor Toll-like receptors (TLRs). We explored signaling convergence between HDM allergens and TLRs in ROS generation because epithelial cells form the primary barrier against inhaled substances and dictate host responses to allergens and viruses. ROS formation by Calu-3 human airway cells was studied by measuring dihydrorhodamine 123 oxidation after activation by polyinosinic:polycytidylic acid (to activate TLR3), CL097 (to activate TLR7), a natural mixture of HDM allergens, or BzATP. TLR4 activation was identified as an indispensable response element for all stimuli, operating downstream from myosin motor activation, pannexon gating for ATP release and the endogenous activation of prothrombin. Exogenous prothrombin activation by HDM allergens was prevented by SGUL 1733, a novel inhibitor of the proteolytic activity of Group 1 HDM allergens, which thus prevented TLR4 from being activated at source. Our data identify for the first time that endogenously-generated prothrombin and TLR4 form a shared effector mechanism essential to intracellular ROS generation activated by a group 1 HDM allergen (itself a prothrombinase) or by ligation of viral RNA-sensing TLRs. These stimuli operate a confluent signaling pathway in which myosin motors, gating of pannexons, and ADAM 10 lead to prothrombin-dependent activation of TLR4 with a recycling activation of pannexons. © 2018 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

A Cost-Minimisation Analysis Comparing Sublingual Immunotherapy to Subcutaneous Immunotherapy for the Treatment of House Dust Mite Allergy in a Swedish Setting.

PubMed

Björstad, Åse; Cardell, Lars-Olaf; Hahn-Pedersen, Julie; Svärd, Mikael

2017-06-01

In Sweden, approximately 6% of children and 10% of adults suffer from house dust mite (HDM) allergy with symptoms of allergic rhinitis and allergic asthma. Treatment is aimed at reducing HDM exposure and to control the symptoms of allergic rhinitis and allergic asthma by symptom-relieving pharmacotherapy. This pharmacotherapy is often effective, but some patients remain inadequately controlled. For these patients, allergy immunotherapy (AIT, subcutaneous or sublingual) with repeated administration of HDM allergen should be considered. The objective of this study was to compare the costs for sublingual AIT (SLIT; SQ ® SLIT-tablet) to the costs for subcutaneous AIT (SCIT; SQ ® SCIT) for the treatment of HDM allergy in a cost-minimisation analysis (CMA). The CMA included resources (and costs) for treatment, healthcare visits, travelling and lost productivity. Resource use based on Swedish clinical treatment practice and costs were obtained from medical price lists. Analyses were conducted from the societal, as well as healthcare perspective, by use of a time horizon of 3 years. The results show that SQ ® SLIT-tablet is a cost-saving treatment as compared to SQ ® SCIT for the treatment of HDM allergy (€6800 over 3 years). The results are mainly driven by the cost of healthcare visits and the frequency of SCIT administrations. In conclusion, cost-savings of €6800 over 3 years are expected from treating HDM allergy with SQ ® SLIT-tablet as compared to SQ ® SCIT, including costs for treatment, healthcare visits, travelling and lost productivity. The reduced number of healthcare visits compensates for higher medication costs.

The influence of house dust mite sublingual immunotherapy on the TSLP-OX40L signaling pathway in patients with allergic rhinitis.

PubMed

Meng, Qingxiang; Liu, Xiaolong; Li, Peng; He, Long; Xie, Jinghua; Gao, Xionghui; Wu, Xiaozhong; Su, Fang; Liang, Yong

2016-08-01

This study aimed to investigate the clinical efficacy of sublingual immunotherapy (SLIT) with house dust mite (HDM) extract and to examine T helper 2 (Th2)-type immune responses mediated by the thymic stromal lymphopoietin (TSLP-OX40L) signaling pathway in patients with moderate to severe allergic rhinitis (AR) after 12-month HDM SLIT. Forty-six cases of HDM-sensitized patients with persistent AR in southern China were enrolled in this study. Clinical efficacy of SLIT was assessed by determining the individual nasal symptom score (INSS) and total nasal symptom score (TNSS) after 12-month HDM SLIT. Moreover, the TSLP-OX40L signaling pathway was investigated through measurements of TSLP by enzyme-labeled immunosorbent assay (ELISA) and OX40L by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and flow cytometry. After 12 months of HDM SLIT, TNSS and INSS were significantly decreased overall compared with baseline values (p < 0.001). By the end of the 12-month HDM SLIT, TNSS had declined by ∼50% compared with baseline, and the corresponding level of TSLP in nasal lavage decreased significantly (p < 0.05). The level of OX40L messenger RNA (mRNA) in blood was markedly decreased significantly after 12-month HDM SLIT compared with baseline (t = 12.300, p < 0.05). Furthermore, significant decreases in OX40L expression on the surface of peripheral blood mononuclear cells (PBMCs) (t = 13.100, p < 0.05) and OX40L expression on the surface of CD11c+CD86+ cells in PBMCs (t = 9.946, p < 0.05) after 12-month HDM SLIT were observed. HDM SLIT downregulated Th2-type immune responses mediated by the TSLP-OX40L signaling pathway in patients with persistent moderate to severe AR. © 2016 ARS-AAOA, LLC.

Studies on the role of routes of allergen exposure in high IgE-producing beagle dogs sensitized to house dust mites.

PubMed

Marsella, R; Nicklin, C; Lopez, J

2006-10-01

The current study aimed to investigate the role played by oral, epicutaneous, and inhalation routes of exposure to house dust mites (HDM). The colony of high IgE-producing beagle dogs has been shown to develop pruritic dermatitis compatible with atopic dermatitis following environmental exposure (EE) to HDM. In crossover experiments, the response to EE was compared to two modified challenges, oral exposure (OE) and snood and muzzle exposure (SME). For OE, HDM were fed daily for 3 days. For SME, ingestion of allergen was prevented but there was inhalation and epicutaneous exposure to all body regions except to one ear. In all experiments, dogs were challenged for three consecutive days, and evaluated before, 6 h after exposure and daily thereafter, for 5 days. After a wash-out period, groups were crossed-over so that each dog was randomly challenged to all three protocols. Clinical scores were analysed using least squares analysis of variance. All dogs developed pruritic dermatitis regardless of the protocol. With OE, lesions developed in the same body regions as with EE although scores were lower. This difference became more evident after the first 3 days when OE scores decreased and EE scores continued to increase. The scores of covered and uncovered ears did not differ with SME. Scores for the remainder of the body were significantly lower than for EE. The development of lesions on covered ears supports the importance of inhalation or a systemic reaction to epicutaneous exposure in other areas. It is concluded that all routes are important and have additive effects, that route of exposure does not determine the distribution of lesions and that continuous epicutaneous exposure probably plays the most important role.

Bioaccessibility of Fipronil Sorbed to Soil and House Dust

EPA Science Inventory

Fipronil is a phenylpyrazole insecticide with uses ranging from soil treatment, to the control of household pests and ectoparasites on pets. Soils and house dusts readily sorb fipronil and when these soils and dusts are ingested, the fipronil may become bioaccessible for uptake ...

Monitoring and reducing exposure of infants to pollutants in house dust.

PubMed

Roberts, John W; Wallace, Lance A; Camann, David E; Dickey, Philip; Gilbert, Steven G; Lewis, Robert G; Takaro, Tim K

2009-01-01

The health risks to babies from pollutants in house dust may be 100 times greater than for adults. The young ingest more dust and are up to ten times more vulnerable to such exposures. House dust is the main exposure source for infants to allergens, lead, and PBDEs, as well as a major source of exposure to pesticides, PAHs, Gram-negative bacteria, arsenic, cadmium, chromium, phthalates, phenols, and other EDCs, mutagens, and carcinogens. Median or upper percentile concentrations in house dust of lead and several pesticides and PAHs may exceed health-based standards in North America. Early contact with pollutants among the very young is associated with higher rates of chronic illness such as asthma, loss of intelligence, ADHD, and cancer in children and adults. The potential of infants, who live in areas with soil contaminated by automotive and industrial emissions, can be given more protection by improved home cleaning and hand washing. Babies who live in houses built before 1978 have a prospective need for protection against lead exposures; homes built before 1940 have even higher lead exposure risks. The concentration of pollutants in house dust may be 2-32 times higher than that found in the soil near a house. Reducing infant exposures, at this critical time in their development, may reduce lifetime health costs, improve early learning, and increase adult productivity. Some interventions show a very rapid payback. Two large studies provide evidence that home visits to reduce the exposure of children with poorly controlled asthma triggers may return more than 100% on investment in 1 yr in reduced health costs. The tools provided to families during home visits, designed to reduce dust exposures, included vacuum cleaners with dirt finders and HEPA filtration, allergy control bedding covers, high-quality door mats, and HEPA air filters. Infants receive their highest exposure to pollutants in dust at home, where they spend the most time, and where the family has the

Monocyte-derived dendritic cells induce a house dust mite-specific Th2 allergic inflammation in the lung of humanized SCID mice: involvement of CCR7.

PubMed

Hammad, Hamida; Lambrecht, Bart N; Pochard, Pierre; Gosset, Philippe; Marquillies, Philippe; Tonnel, André-Bernard; Pestel, Joël

2002-08-01

In rodents, airway dendritic cells (DCs) capture inhaled Ag, undergo maturation, and migrate to the draining mediastinal lymph nodes (MLN) to initiate the Ag-specific T cell response. However, the role of human DCs in the pathogenesis of the Th2 cell-mediated disease asthma remains to be clarified. Here, by using SCID mice engrafted with T cells from either house dust mite (HDM)-allergic patients or healthy donors, we show that DCs pulsed with Der p 1, one of the major allergens of HDM, and injected intratracheally into naive animals migrated into the MLN. In the MLN, Der p 1-pulsed DCs from allergic patients induced the proliferation of IL-4-producing CD4(+) T cells, whereas those from healthy donors induced IFN-gamma-secreting cells. In reconstituted human PBMC-reconstituted SCID mice primed with pulsed DCs from allergic patients, repeated exposure to aerosols of HDM induced 1) a strong pulmonary inflammatory reaction rich in T cells and eosinophils, 2) an increase in IL-4 and IL-5 production in the lung lavage fluid, and 3) increased IgE production compared with that in mice primed with unpulsed DCs. All these effects were reduced following in vivo neutralization of the CCR7 ligand secondary lymphoid tissue chemokine. These data in human PBMC-reconstituted SCID mice show that monocyte-derived DCs might play a key role in the pathogenesis of the pulmonary allergic response by inducing Th2 effector function following migration to the MLN.

Dust mite, cockroach, cat, and dog allergen concentrations in homes of asthmatic children in the northeastern United States: impact of socioeconomic factors and population density.

PubMed Central

Leaderer, Brian P; Belanger, Kathleen; Triche, Elizabeth; Holford, Theodore; Gold, Diane R; Kim, Young; Jankun, Thomas; Ren, Ping; McSharry Je, Jean-ellen; Platts-Mills, Thomas A E; Chapman, Martin D; Bracken, Michael B

2002-01-01

Home exposures to aeroallergens are an important environmental factor in allergic sensitization and in the development and exacerbation of asthma. We assessed variations in home concentrations of dust mite, cockroach, cat, and dog allergens in dust collected in the main living areas of asthmatics' homes by family income, mother's education, dwelling type, population density, household population density, and ethnicity in Connecticut and south-central Massachusetts. Dust samples were collected at the time of home interview in 999 homes as part of an ongoing longitudinal birth cohort study of 1,002 infants and their asthmatic siblings. The analysis employed lower and upper cut points for group 1 dust mite (> or = 2.0 microg/g and > or = 10 microg/g), cockroach (> or = 1.0 U/g and > or = 4.0 U/g), cat (> or = 1.0 microg/g and > or = 8.0 ug/g), and dog (> or = 2.0 microg/g and > or = 10.0 microg/g) allergens. Subject residences were geocoded to assess population density from the U.S. Census, and multiple logistic regression was used to control for confounding. The portion of homes at the lower cut point for dust mite, cockroach, cat, and dog allergens were 46.9%, 24.9%, 42.2%, and 35.6%, respectively; the upper cut point for each of the allergens was reached in 22.4%, 13.4%, 21.0%, and 22.9% of the homes, respectively. In all, 86.0% of the homes had at least one allergen at the lower cut point, and 58.0% had at least one allergen at the upper cut point. Forty-nine percent of the homes had two or more allergens at the lower cut point, and 19.7% had two or more allergens at the upper cut point. Higher education of the mother, higher household income, living in a single-family home in a less densely populated area with fewer people per room, and being a white household were associated with elevated dust mite, cat, and dog allergens and low cockroach allergen. In contrast, low income, living in a multifamily home in a high population density area with a higher occupancy

[Detection of mite allergens in the dust of filter-net and air of air-conditioned room].

PubMed

Lian, Yu-yin; Liu, Zhi-gang; Wang, Hong-yu; Chai, Cheng-yu; Liu, Xiao-yu

2007-08-01

To detect mite allergens in the dust of air conditioner filter-net and floating air in room. Samples were collected from rooms of asthma patient and normal families with or without air conditioner. Der p1, Der f1 and Der 2 were determined by two monoclonal antibody-based ELISA. In asthma patient families, the concentration of airborne Der p1, Der f1 and Der 2 was (0.23 +/- 0.13), (2.62 +/- 1.08), (0.93 +/- 0.41) ng/m3, and (0.56 +/- 0.25), (4.74 +/- 1.22), (2.33 +/- 0.64) ng/m3 respectively before and after the air conditioner switched on, all showing a significant difference (P < 0.05). In families without asthma patient, the concentration of Der p1, Der f1 and Der 2 was (0.33 +/- 0.11), (11.50 +/- 3.08) and (2.10 +/- 0.80) ng/m3, and (0.63 +/- 0.23), (19.80 +/- 4.30) and (3.60 +/- 1.00) ng/m3 respectively before and after the air conditioner switched on, also showing a significant difference (P < 0.05). From the filter-net dust of air conditioner in family with allergic asthma patient, the concentration of Der p1, Der f1 and Der 2 was (0.52 +/- 0.19), (3.34 +/- 0.63), (2.53 +/- 0.65) microg/g dust, while that of normal families was (1.30 +/- 0.35), (5.16 +/- 0.92), (3.47 +/- 1.13) microg/g dust respectively. The concentration of Der f1 and Der 2 at both asthma families and normal families was higher than 2 microg/g, an allergen concentration threshold. Mite allergens exist in the filter-net dust of air conditioner, which may be an important source of indoor allergens and a cause of the increasing prevalence of allergic asthma.

Dust-bathing behavior of laying hens in enriched colony housing systems and an aviary system

PubMed Central

Louton, H.; Bergmann, S.; Reese, S.; Erhard, M. H.; Rauch, E.

2016-01-01

The dust-bathing behavior of Lohmann Selected Leghorn hens was compared in 4 enriched colony housing systems and in an aviary system. The enriched colony housing systems differed especially in the alignment and division of the functional areas dust bath, nest, and perches. Forty-eight-hour video recordings were performed at 3 time-points during the laying period, and focal animal sampling and behavior sampling methods were used to analyze the dust-bathing behavior. Focal animal data included the relative fractions of dust-bathing hens overall, of hens bathing in the dust-bath area, and of those bathing on the wire floor throughout the day. Behavior data included the number of dust-bathing bouts within a predefined time range, the duration of 1 bout, the number of and reasons for interruptions, and the number of and reasons for the termination of dust-bathing bouts. Results showed that the average duration of dust bathing varied between the 4 enriched colony housing systems compared with the aviary system. The duration of dust-bathing bouts was shorter than reported under natural conditions. A positive correlation between dust-bathing activity and size of the dust-bath area was observed. Frequently, dust baths were interrupted and terminated by disturbing influences such as pecking by other hens. This was especially observed in the enriched colony housing systems. In none of the observed systems, neither in the enriched colony housing nor in the aviary system, were all of the observed dust baths terminated “normally.” Dust bathing behavior on the wire mesh rather than in the provided dust-bath area generally was observed at different frequencies in all enriched colony housing systems during all observation periods, but never in the aviary system. The size and design of the dust-bath area influenced the prevalence of dust-bathing behavior in that small and subdivided dust-bath areas reduced the number of dust-bathing bouts but increased the incidence of sham dust

Subtropical acarien profile by topography, seasons and change of house furnishings: 80's blueprint to the future.

PubMed

Massey, Douglas G; Hope, Bradley E; Furumizo, Roy T

2010-04-01

In Hawai'i, mortality and morbidity from asthma are significant. In the 80's, there had been no local studies of topography folklore. There had been only one report of seasonal variation in house dust mite (HDM) density in Hawai'i, and this showed no significant variation in O'ahu's Manoa Valley but a definite variation in Waikiki. There were no studies of complete replacement of furnishings. In this pilot study, homes in a valley, coastal, and plain sites were investigated for 12 months in 2 homes on O'ahu. A 3rd home was studied prior to and after arrival of furnishings from Denver, Colorado. Of the 3 homes, #1 was in Palolo Valley Honolulu, #2 coastal at Pearl Harbor and #3 on the plain at Mililani. House dust samples were taken from 4-5 sites in 2 rooms every 5 weeks. Sampling and determination of density and species were those of Furumizo. They were unsupportive of the topography and seasonal variation folklore. Density surged in the 3rd home to > 12000 mites/ gram of dust within 10-15 weeks with the complete change of low density HDM furnishings. D. pteronyssinus (Dp) was dominant in each home year-round. Minor species of mites made up to 1/3 of total mites in 2 homes. The folklore relating improvement in asthma to geography was not supported. 2 of the 3 homes showed minimal seasonal variation in HDM density. Local mites heavily colonized furniture from high altitude Colorado in a surge within 10-15 weeks.

Prevalence and clinical characteristics of adult-onset atopic dermatitis with positive skin prick testing to mites.

PubMed

Kulthanan, Kanokvalai; Chularojanamontri, Leena; Manapajon, Araya; Nuchkull, Piyavadee

2011-12-01

The clinical role of house dust mite (HDM) in atopic dermatitis (AD) is still controversial. The aim of the study is to assess the prevalence, clinical relevance and characteristics of adult-onset AD patients with positive skin prick tests (SPT) to mites. The case record forms of adult-onset AD patients who underwent SPT at the Skin Allergy Clinic, Siriraj Hospital were reviewed. Forty-one of 62 patients (66.1%) had positive SPT to mites. The frequency of intrinsic AD among adult-onset AD was 4.8% (3/62). SPT to HDM tended to be positive in patients who had personal or family history of atopy, positive SPT to several specific antigens or who presented with elevated serum IgE, chelitis, recurrent conjunctivitis and perifollicular accentuation, respectively. CONCLUSION The prevalence of adult-onset AD patients with mite sensitivity was high. There were some notable features that tended to be present in mite sensitive adult-onset AD patients.

Correlation of skin test results and specific immunoglobulin E blood levels with nasal provocation testing for house-dust mite allergies.

PubMed

Haxel, Boris R; Huppertz, Tilman; Boessert, Patrick; Bast, Florian; Fruth, Kai

2016-01-01

Allergen-specific immunotherapy for house-dust mite (HDM) allergies is associated with lower success rates when compared with similar treatments for other inhalant allergens, such as grass or birch. One reason might be the greater difficulty in diagnosing patients with assumed HDM allergies because symptoms occur perennially and may differ from those of a conventional allergic rhinitis. The aim of the study was to compare the different methods of diagnosis in patients with assumed HDM allergy. We performed a retrospective analysis of nasal provocation tests (NPT) from patients (n = 161) evaluated for Dermatophagoides pteronyssinus (n = 127) and Dermatophagoides farinae (n = 104) allergies, and compared the results with other allergen testing methods (skin-prick test [SPT], intracutaneous test, and allergen specific immunoglobulin E levels [sIgE] to detect sensitization). Receiver operating characteristic curves were used for the analyses and the areas under the curve were calculated. For D. pteronyssinus and D. farinae, 86 and 70 complete data files, respectively, were available. For both tested HDMs, the results of the receiver operating characteristic curves showed a significant correlation for SPT and sIgE, with the results of the NPT (area under the curve, 0.742 to 0.763) but not for the intracutaneous test. In patients with a positive SPT (≥3 mm), an allergy was confirmed by the NPT in 69% of cases for D. pteronyssinus and 71% for D. farinae. A positive sIgE result (ImmunoCAP class of ≥2) was verified by the NPT in 69% of cases (D. pteronyssinus) and 70% (D. farinae). The predictability value for a positive NPT result is best for SPT and sIgE. Nevertheless, even if the results of both test systems are combined, the positive predictive value that was achieved was only 0.77 for D. pteronyssinus and 0.69 for D. farinae. Therefore, in patients eligible for immunotherapy for HDM, an NPT should be performed before the start of the therapy to verify a clinically

The effects of inhaled corticosteroids on intrinsic responsiveness and histology of airways from infant monkeys exposed to house dust mite allergen and ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joad, Jesse P.; Kott, Kayleen S.; Bric, John M.

2008-01-15

Inhaled corticosteroids (ICS) are recommended to treat infants with asthma, some with intermittent asthma. We previously showed that exposing infant monkeys to allergen/ozone resulted in asthma-like characteristics of their airways. We evaluated the effects of ICS on histology and intrinsic responsiveness of allergen/ozone-exposed and normal infant primate airways. Infant monkeys were exposed by inhalation to (1) filtered air and saline, (2) house dust mite allergen (HDMA) + ozone and saline, (3) filtered air and ICS (budesonide) or (4) HDMA + ozone and ICS. Allergen/ozone exposures started at 1 month and ICS at 3 months of age. At 6 months ofmore » age, methacholine-induced changes in luminal area of airways in proximal and distal lung slices were determined using videomicrometry, followed by histology of the same slices. Proximal airway responsiveness was increased by allergen/ozone and by ICS. Eosinophil profiles were increased by allergen/ozone in both proximal and distal airways, an effect that was decreased by ICS in distal airways. In both allergen/ozone- and air-exposed monkeys, ICS increased the number of alveolar attachments in distal airways, decreased mucin in proximal airways and decreased epithelial volume in both airways. ICS increased smooth muscle in air-exposed animals while decreasing it in allergen/ozone-exposed animals in both airways. In proximal airways, there was a small but significant positive correlation between smooth muscle and airway responsiveness, as well as between alveolar attachments and responsiveness. ICS change morphology and function in normal airways as well as allergen/ozone-exposed airways, suggesting that they should be reserved for infants with active symptoms.« less

The correlation between intradermal testing and serum specific IgE to house dust mite in negative skin prick test allergic rhinitis adult patients.

PubMed

Tantilipikorn, Pongsakorn; Danpornprasert, Piyanart; Ngaotepprutaram, Premyot; Assanasen, Paraya; Bunnag, Chaweewan; Thinkhamrop, Bandit

2015-12-01

Diagnosis of allergic rhinitis (AR) is based on history, physical examination, and skin prick test (SPT) while intradermal (ID) test can be performed to confirm the diagnosis in case of negative result of SPT. However, the ID test is not recommended for cat and timothy grass allergy because of its high false positive rate. As a result, the "quantitative" technique of serum specific IgE (sIgE) measurement might be helpful to diagnose AR with more confidence. To evaluate the correlation between ID tests and sIgE in the diagnosis of house dust mite (HDM)-sensitive AR patients. Patients with chronic rhinitis (CR) were recruited and SPT was performed. If SPT was negative, ID test and sIgE to HDM [Dermatophagoides pteronyssinus (Dp)] measurement were performed. Eighty-two patients with chronic rhinitis (CR), whose SPTs were negative for Dp, were included. There were 39 males (47.6%) and 43 females (52.4%) aged between 18 and 76 years old (mean age = 43.3 years). The ID test was positive in 13 patients (15.9%), and was negative in 69 patients (84.1 %). sIgE to HDM was positive ( ≥ 0.35 kUA/l) in 2 patients (2.4%). There was a fair to moderate correlation between the size of wheal of ID test and sIgE to HDM (r = 0.44, 95% confidence interval: 0.19 to 0.67, p < 0.01). ID test has a fair to moderate correlation with sIgE Dermatophagoides pteronyssinus and it can be used in CR patients with negative SPT where sIgE is not feasible.

Airway toxicity of house dust and its fungal composition.

PubMed

Piecková, Elena; Wilkins, Ken

2004-01-01

House dust is an important source of different toxic metabolites as well as allergens, including those of fungal origin, in the indoor environment. A bio-assay employing 1-day-old chick tracheas was used to characterize airway effects of 2-butanone and dimethylsulphoxide (Me2SO) extracts of 23 dust samples collected from water damaged (13) and control (10) Danish schools. Direct microscopical analysis of samples, followed by cultivation on dichloran 18 % glycerol agar at 25 degrees C for 10 days to establish their mycoflora, was performed. The in vitro ciliostatic potential of the chloroform-extractable endo- and exometabolites of 41 representative fungal isolates was determined. Nine dust extracts in 2-butanone (2 from damp rooms) or 10 (6) in Me(2)SO showed some ciliostatic activity in the 3-days' experiment. Fungal composition of dust from buildings with leakage was almost identical with that from undamaged houses, as well as the fungal colony counts from the damp schools and the control samples. Aspergillus spp. were prevalent in the samples - 31 or 40 % of all fungi, followed by Penicillium spp. and Cladosporium cladosporioides. Alternaria spp., Chaetomium spp., Mucor spp., Mycelia sterilia, Paecilomyces variotii, Rhizopus sp., Ulocladium sp. and yeasts were each isolated in less than 8 % of the fungal content. No Aspergillus flavus isolate (8 in total) was aflatoxigenic,em>in vitro. Alternaria spp., Aspergillus spp., Botrytis cinerea, Penicillium spp., C. cladosporioides, Chaetomium spp. and Ulocladium sp.; in total, 88 % of all fungi tested, produced ciliostatically active metabolites. These toxigenic strains were also present in 4 dust samples from controls and 5 dust samples from water damaged buildings. Extracts of these dust samples were also toxic in bioassay. There were bio-detectable concentrations (10-20 microg of extracts/ml of the organ culture medium) of toxic compounds in house dust. Contribution of fungal metabolites to its toxic effect should

Fluorescence detection of protein content in house dust: the possible role of keratin.

PubMed

Voloshina, O V; Shirshin, E A; Lademann, J; Fadeev, V V; Darvin, M E

2017-03-01

We propose a fluorescence method for protein content assessment in fine house dust, which can be used as an indicator of the hygienic state of occupied rooms. The results of the measurements performed with 30 house dust samples, including ultrafiltration experiments, strongly suggest that the fluorescence emission of house dust extracts excited at 350 nm is mainly due to protein fragments, which are presumably keratin hydrolysates. This suggestion is supported by several facts: (i) Spectral band shapes for all the samples under investigation are close and correspond to that of keratin; (ii) fluorescence intensity correlates with the total protein content as provided by Lowry assay; (iii) treatment of the samples with proteinase K, which induces keratin hydrolysis, results in fluorescence enhancement without changing fluorescence band shape; and (iv) Raman spectra of keratin and fine house dust samples exhibit a very similar structure. Based on the obtained results and literature data, we propose a hypothesis that keratin is a major substrate for fluorescence species in fine house dust, which are responsible for emission at 350-nm excitation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Field efficacy of phoxim 50% (ByeMite) against the poultry red mite Dermanyssus gallinae in battery cages stocked with laying hens.

PubMed

Meyer-Kühling, Borris; Pfister, Kurt; Müller-Lindloff, Jürgen; Heine, Josef

2007-07-20

Infestations with the poultry red mite Dermanyssus gallinae represent a major ectoparasite problem in poultry and can affect egg layers worldwide. There is presently a lack of an ectoparasiticide in Europe for poultry which can assure a 0-day withholding period for eggs. In this study, ByeMite (phoxim 50%, Bayer HealthCare, Animal Health Division) was administered to treat a D. gallinae infestation in a poultry house stocked with egg-laying hens kept in a cage system. A layer house was sprayed twice within a 7-day interval using a solution containing 2000 ppm phoxim and a similar layer house was used as an untreated control unit. Specially developed D. gallinae traps made of cardboard were used to assess the mite density in both layer houses during a 49-day period after the treatment. In order to collect mites, the traps were placed on days--1, 2, 6, 9, 13, 20, 34 and 48 and always removed after 24 h. The collected mites were counted and differentiated according to their developmental stage (mite eggs, larvae, nymphs, adults). Three days after the first spray treatment, the efficacy against all mite stages (larvae, nymphs, adults) was 96.1%, and from day 7 post-treatment until the end of the trial (day 49) the efficacy exceeded 99%. In contrast, in the untreated layer house (negative control group) the mite population showed a 400% increase. No treatment-related side effects in chickens were detectable. It is concluded that two administrations of ByeMite within a 7-day interval are highly effective against D. gallinae infestations in a stocked poultry house.

Effective allergen avoidance for reducing exposure to house dust mite allergens and improving disease management in adult atopic asthmatics.

PubMed

Tsurikisawa, Naomi; Saito, Akemi; Oshikata, Chiyako; Yasueda, Hiroshi; Akiyama, Kazuo

2016-10-01

We investigated the best strategy for adult asthmatics to avoid exposure to Dermatophagoides group (Der-1) allergens. Adult atopic asthmatics (n = 111) followed a 32-item checklist for avoiding Der-1 allergen exposure. Twenty-five patients were excluded through incomplete sampling; 50 remaining patients encased their pillows/futons/mattresses in microfine-fiber covers, 13 used vacuum cleaners with dust-mite-collection nozzles, and 23 acted as non-intervention controls. During August-October 2010 and August-October 2011, dust samples were collected in Petri dishes placed in bedrooms for 2 weeks and from mattresses/futons by using adhesive tape on one morning. A Der-1 level decrease was defined as a mean 2011 Der-1 level of <1 as a ratio of the 2010 level on tape or Petri dish samples. We analyzed the associations between Der-1 level change (by ELISA) and % weekly variability in peak expiratory flow (PEF) or fraction of exhaled nitric oxide (FeNO) after intervention. Der-1 levels decreased significantly in the covers group but not the vacuuming group. FeNO levels and PEF variability were unchanged in both groups. In patients whose Petri dish or tape samples showed decreased Der-1 levels, the % PEF variability was lower in 2011 than in 2010, but FeNO levels were unchanged. Three interventions (vacuuming all family members' mattress/futon surfaces at least weekly or after exposure of the futons to sunlight, and floor wiping before vacuuming), plus using covers, were the most effective management strategy in reducing Der-1 levels. This environmental and bedding maintenance program may help manage adult atopic asthma.

Environmental interventions for mite-induced asthma: a journey between systematic reviews, contrasting evidence and clinical practice.

PubMed

Pingitore, G; Pinter, E

2013-05-01

House dust mites (HDM) are one of the most important sources of indoor allergens worldwide. Exposure to high environmental levels of dust mite allergen is associated with an increased risk of sensitization, asthma and deterioration of lung function. On the basis of these data, it would be logical to assume that asthmatic patients with mite allergy could benefit from a reduction of exposure to these allergens. Several environmental prophylactic actions against HDM, either physical or chemical have been tried, alone or in different combinations. However, a recent Cochrane Systematic Review did not detect specific clinical benefits from the use of prophylactic environmental measures in asthmatic patients sensitive to HDM and concluded that such measures can no longer be recommended as they are ineffective. This paper presents the results of a web-based questionnaire, administered to more than 200 Italian paediatricians, and shows that physicians' behaviour in real life is very far from SR conclusions. It also summarizes the indications of the most authoritative guidelines, highlighting some contrasting evidence and some significant weaknesses of the SR, that could make the final conclusions at least uncertain. In the light of these findings, it seems that the recent Cochrane SR cannot be considered the definitive document on the uselessness of environmental prevention of mite-related asthma.

Exposures Related to House Dust Microbiota in a U.S. Farming Population.

PubMed

Lee, Mi Kyeong; Carnes, Megan U; Butz, Natasha; Azcarate-Peril, M Andrea; Richards, Marie; Umbach, David M; Thorne, Peter S; Beane Freeman, Laura E; Peddada, Shyamal D; London, Stephanie J

2018-06-01

Environmental factors can influence the house dust microbiota, which may impact health outcomes. Little is known about how farming exposures impact the indoor microbiota. We aimed to identify exposures related to bacterial communities in house dust in a U.S. farming population. We used 16S rRNA amplicon sequencing to characterize bacterial communities in vacuumed dust samples from the bedrooms of a subset of 879 households of farmers and farmers' spouses enrolled in the Agricultural Lung Health Study (ALHS), a case-control study of asthma nested within the Agricultural Health Study (AHS) in North Carolina and Iowa. Information on current farming (past 12 mo), including both crop and animal farming, and other potential microbial sources was obtained via questionnaires. We used linear regression to evaluate associations between exposures and bacterial diversity within each sample, analysis of similarity (ANOSIM), and permutational multivariate analysis of variance (PERMANOVA) to identify exposures related to diversity between samples, and analysis of composition of microbiome to examine whether exposures related to diversity were also related to differential abundance of specific operational taxonomic units (OTUs). Current farming was positively associated with bacterial diversity in house dust, with or without adjustment for nonfarm exposures related to diversity, including presence of indoor pets, home condition, and season of dust collection. Many taxa exhibited differential abundance related to farming. Some taxa in the phyla Chloroflexi and Verrucomicrobia were associated [false discovery rate (FDR)<0.05] with farming but not with other nonfarm factors. Many taxa correlated with the concentration of house dust of endotoxin, commonly studied as a general marker of exposure to the farming environment. In this farming population, house dust microbiota differed by current farming status. Understanding the determinants of the indoor microbiota is the first step

Allergens in household dust and serological indicators of atopy and sensitization in Detroit children with history-based evidence of asthma.

PubMed

Williams, Ann Houston; Smith, James Travis; Hudgens, Edward E; Rhoney, Scott; Ozkaynak, Halûk; Hamilton, Robert G; Gallagher, Jane E

2011-09-01

Home exposure to allergens is an important factor in the development of sensitization and subsequent exacerbations of allergic asthma. We investigated linkages among allergen exposure, immunological measurements, and asthma by examining (1) reservoir dust allergen levels in homes, (2) associations between presence of allergens in homes and sensitization status of resident children, and (3) associations between asthma status and total IgE, atopy (by Phadiatop), and positive allergen-specific tests. The study protocol was approved by Institutional Review Boards (IRBs) of the University of North Carolina Chapel Hill; Westat, Inc.; and the US Environmental Protection Agency Human Research Protocol Office. Data were collected from questionnaires, serum analyses, and household vacuum dust. Children (n = 205) were predominately African American (AA) (85.4%) and 51.6% were asthmatic. Sera from 185 children and home dust samples (n = 141) were analyzed for total and specific IgE antibodies to allergens from cat and dog dander, cockroach, dust mites, mice, rats, and molds. Sixty percent of the homes had detectable levels of three or more dust allergens. The proportions of children with positive allergen-specific IgE tests were dust mite (32%), dog (28%), cat (23%), cockroach (18%), mouse (5%), rat (4%), and molds (24-36%). Children testing positive to a single allergen also had positive responses to other allergens. Those children with positive serum tests for cat, dog, and dust mite lived in homes with detectable levels of cat (51%), dog (90%), and dust mite (Der f 1) (92%) allergens. Correlations between children's specific IgE levels and dust levels were linearly related for dog (p < .04), but not for cat (p = .12) or dust mite (Der f 1) (p = .21). Odds ratios (95% CI) for the associations between asthma and serum-specific IgE were over 1.0 for cat, dog, dust mite (Der f 1), cockroach, and four types of molds. House dust allergen exposure levels, however, exhibited no

Levels and profiles of organochlorines and flame retardants in car and house dust from Kuwait and Pakistan: implication for human exposure via dust ingestion.

PubMed

Ali, Nadeem; Ali, Lulwa; Mehdi, Toufeer; Dirtu, Alin C; Al-Shammari, Fatema; Neels, Hugo; Covaci, Adrian

2013-05-01

There are only few studies documenting indoor pollution in the Middle East and the Indian subcontinent. In present study, we have evaluated the occurrence of various organochlorines (OCs) and flame retardants (FRs) in dust from cars and houses of Pakistan and Kuwait. Polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), organophosphate FRs (PFRs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were investigated in indoor dust from urban houses (N=15 per country) and cars (N=15 per country). PFRs were the major analytes in all four microenvironments, followed by PBDEs>NBFRs>OCPs>PCBs. For all classes of analytes, relatively lower levels were observed in car and house dust from Pakistan than Kuwait. Levels of ∑PBDEs, ∑NBFRs and ∑PFRs were higher in car dust, while ∑OCPs and ∑PCBs were higher in house dust from both countries. ∑PFRs occurred at average concentrations of 16,900, 87,900, 475, and 2500ng/g in Kuwaiti house and car, and Pakistani house and car dust, respectively. For both countries, the profiles of analytes in car dust were different from those in the house dust. Different exposure scenarios using 5th percentile, median, mean, and 95th percentile levels were estimated for adult, taxi drivers and toddlers. For Kuwaiti toddlers, assuming high dust intake and mean and 95th percentile concentrations, the values computed for ∑OCPs (1500ng/kg bw/day) were higher than RfD values, while for ∑PCBs (14.5ng/kg bw/day) it was only two-fold lower than the corresponding RfDs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Dust and airborne exposure to allergens derived from cockroach (Blattella germanica) in low-cost public housing in Strasbourg (France).

PubMed

de Blay, F; Sanchez, J; Hedelin, G; Perez-Infante, A; Vérot, A; Chapman, M; Pauli, G

1997-01-01

Although a strong association between allergy to cockroach (CR) and asthma has been observed in the United States and Asia, there are little data about the extent of exposure to CR allergen in Europe. To determine the levels of CR allergens in dust samples from apartments in Strasbourg and to determine the concentration and size of CR allergens in the air. Nine apartments in a public housing complex were chosen on the basis of visual evidence of CR infestation. Levels of CR allergens (Bla g 1 and Bla g 2) in kitchen and mattress dust samples were measured by immunoassay with the use of monoclonal antibodies. Air was sampled for 3 to 8 hours in the kitchen under undisturbed conditions, during artificial disturbance, and during normal domestic activity by using an impinger and a parallel glass fiber filter and at flow rates of 2 to 20 L/min. Airborne CR and mite allergens were measured concurrently in the bedroom of one apartment before, during, and after artificial disturbance. High levels of Bla g 1 and Bla g 2 were found in kitchen dust from the nine apartments (geometric means of 3919 U/gm [range 530 to 14306 U/gm] and 497 U/gm [range 73 to 1946 U/gm], respectively). Under undisturbed conditions, airborne CR allergens were not detectable in any of the apartments. During vigorous artificial disturbance, Bla g 1 and Bla g 2 were detectable in air samples from seven apartments (geometric means of 4.5 U/m3 [range 0.7 to 17.2 U/m3] and 1.0 U/m3 [range 0.4 to 3.4 U/m3], respectively). Both allergens were predominantly collected on the first stage of the impinger, and 76% to 80% of the airborne allergen was associated with particles greater than 10 microns in diameter. The levels were significantly higher than those collected on the second or third stages of the impinger (p < 0.001). A comparison of the levels of mite and CR allergens showed that the airborne properties of these allergens were similar, that is, measurable only during disturbance and not detectable 30

Immunoproteomic analysis of house dust mite antigens reveals distinct classes of dominant T cell antigens according to function and serological reactivity

PubMed Central

Westernberg, Luise; Pham, John; Lane, Jerome; Paul, Sinu; Greenbaum, Jason; Stranzl, Thomas; Lund, Gitte; Hoof, Ilka; Holm, Jens; Würtzen, Peter A; Meno, Kåre H.; Frazier, April; Schulten, Veronique; Andersen, Peter S.; Peters, Bjoern; Sette, Alessandro

2016-01-01

BACKGROUND House dust mite (HDM) allergens are a common cause of allergy and allergic asthma. A comprehensive analysis of proteins targeted by T cells, which are implicated in the development and regulation of allergic disease independent of their antibody reactivity, is still lacking. OBJECTIVE To comprehensively analyze the HDM-derived protein targets of T cell responses in HDM-allergic individuals, and investigate their correlation with IgE/IgG responses and protein function. METHODS Proteomic analysis (liquid chromatography tandem mass spectrometry) of HDM extracts identified 90 distinct protein clusters, corresponding to 29 known allergens and 61 novel proteins. Peripheral blood mononuclear cells (PBMC) from 20 HDM-allergic individuals were stimulated with HDM extracts and assayed with a set of ~2500 peptides derived from these 90 protein clusters and predicted to bind the most common HLA class II types. 2D immunoblots were made in parallel to elucidate IgE and IgG reactivity and putative function analyses were performed in silico according to gene ontology (GO) annotations. RESULTS Analysis of T cell reactivity revealed a large number of T cell epitopes. Overall response magnitude and frequency was comparable for known and novel proteins, with 15 antigens (nine of which were novel) dominating the total T cell response. Most of the known allergens that were dominant at the T cell level were also IgE-reactive, as expected, while few novel dominant T cell antigens were IgE reactive. Among known allergens, hydrolase activity and detectable IgE/IgG reactivity are strongly correlated, while no protein function correlates with immunogenicity of novel proteins. A total of 106 epitopes accounted for half of the total T-cell response, underlining the heterogeneity of T cell responses to HDM allergens. CONCLUSIONS AND CLINICAL RELEVANCE Herein, we define the T cell targets for both known allergens and novel proteins, which may inform future diagnostics and

Organophosphorus flame retardants (PFRs) and plasticizers in house and car dust and the influence of electronic equipment.

PubMed

Brandsma, Sicco H; de Boer, Jacob; van Velzen, Martin J M; Leonards, Pim E G

2014-12-01

All nine PFRs studied were detected in house and car dust from the Netherlands with the exception of tris(butyl) phosphate (TNBP) and tris(isobutyl) phosphate (TIBP) in car dust. Tris(2-butoxyethyl) phosphate (TBOEP, median 22 μg g(-1)) was dominant in house dust collected around and on electronics followed by tris(2-chloroisopropyl) phosphate (TCIPP, median 1.3 μg g(-1)), tris(2-chloroethyl) phosphate (TCEP, median 1.3 μg g(-1)) and tris(phenyl) phosphate (TPHP, median 0.8 μg g(-1)). Levels of TPHP and tris(methylphenyl) phosphate (TMPP, also known as TCP) in house dust on electronics were significantly higher than in house dust collected around electronics, suggesting that electronic equipment has limited contribution to the PFR levels in house dust, with the exception of TPHP and TMPP. Car dust was dominated by tris(1,3-dichloroisopropyl) phosphate (TDCIPP) with the highest levels found in dust collected from the car seats (1100 μg g(-1)). The mean TDCIPP and TCIPP levels observed in car dust were significantly higher than the levels observed in dust collected around electronics. Significantly higher mean TMPP levels in dust taken from car seats were found compared to dust collected around the equipment (p<0.05). This is probably influenced by the use of TDCIPP, TCIPP in polyurethane foam (car seats) and the use of TMPP as plasticizer in car interiors. Worldwide four PFR patterns were observed in house dust. The PFR pattern in the Netherlands of TDCIPP, TMPP, TCEP, TCIPP and TPHP in house dust is comparable to the pattern found in six other countries, which may point to identical sources of these PFRs in the indoor environment. However, the PFR levels between the countries and within countries showed high variation. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Translational Repressor T-cell Intracellular Antigen-1 (TIA-1) is a Key Modulator of Th2 and Th17 Responses Driving Pulmonary Inflammation Induced by Exposure to House Dust Mite

PubMed Central

Simarro, Maria; Giannattasio, Giorgio; Xing, Wei; Lundequist, Emma-Maria; Stewart, Samantha; Stevens, Richard L.; Orduña, Antonio; Boyce, Joshua A.; Anderson, Paul J.

2012-01-01

T-cell Intracellular Antigen-1 (TIA-1) is a translational repressor that dampens the production of proinflammatory cytokines and enzymes. In this study we investigated the role of TIA-1 in a mouse model of pulmonary inflammation induced by exposure to the allergenic extract (Df) of the house dust mite Dermatophagoides farinae. When intranasally challenged with a low dose of Df, mice lacking TIA-1 protein (Tia-1−/−) showed more severe airway and tissue eosinophilia, infiltration of lung bronchovascular bundles, and goblet cell metaplasia than wild-type littermates. Tia-1−/− mice also had higher levels of Df-specific IgE and IgG1 in serum and ex vivo restimulated Tia-1−/− lymph node cells and splenocytes transcribed and released more Th2/Th17 cytokines. To evaluate the site of action of TIA-1, we studied the response to Df in bone marrow chimeras. These experiments revealed that TIA-1 acts on both hematopoietic and non-hematopoietic cells to dampen pulmonary inflammation. Our results identify TIA-1 as a negative regulator of allergen-mediated pulmonary inflammation in vivo. Thus, TIA-1 might be an important player in the pathogenesis of bronchial asthma. PMID:22525013

The translational repressor T-cell intracellular antigen-1 (TIA-1) is a key modulator of Th2 and Th17 responses driving pulmonary inflammation induced by exposure to house dust mite.

PubMed

Simarro, Maria; Giannattasio, Giorgio; Xing, Wei; Lundequist, Emma-Maria; Stewart, Samantha; Stevens, Richard L; Orduña, Antonio; Boyce, Joshua A; Anderson, Paul J

2012-08-30

T-cell intracellular antigen-1 (TIA-1) is a translational repressor that dampens the production of proinflammatory cytokines and enzymes. In this study we investigated the role of TIA-1 in a mouse model of pulmonary inflammation induced by exposure to the allergenic extract (Df) of the house dust mite Dermatophagoides farinae. When intranasally challenged with a low dose of Df, mice lacking TIA-1 protein (Tia-1(-/-)) showed more severe airway and tissue eosinophilia, infiltration of lung bronchovascular bundles, and goblet cell metaplasia than wild-type littermates. Tia-1(-/-) mice also had higher levels of Df-specific IgE and IgG(1) in serum and ex vivo restimulated Tia-1(-/-) lymph node cells and splenocytes transcribed and released more Th2/Th17 cytokines. To evaluate the site of action of TIA-1, we studied the response to Df in bone marrow chimeras. These experiments revealed that TIA-1 acts on both hematopoietic and non-hematopoietic cells to dampen pulmonary inflammation. Our results identify TIA-1 as a negative regulator of allergen-mediated pulmonary inflammation in vivo. Thus, TIA-1 might be an important player in the pathogenesis of bronchial asthma. Copyright © 2012 Elsevier B.V. All rights reserved.

Kawasaki syndrome: a controlled study of an outbreak in Wisconsin.

PubMed

Klein, B S; Rogers, M F; Patrican, L A; White, M C; Burgdorfer, W; Schell, W L; Kochel, R L; Marchette, N J; McPherson, J T; Nelson, D B

1986-08-01

The etiology of Kawasaki syndrome remains unestablished, although a possible role has been suggested for exposure to the application of carpet shampoo, house dust mites, and rickettsial infection. During an outbreak of 20 cases of Kawasaki syndrome that occurred in southeastern Wisconsin from November 1982 through March 1983, a case-control study was done of 15 cases and 30 matched controls. The study included questionnaire administration, dust collection from homes, and serum specimen collection. Only one patient had been exposed to a shampooed carpet within 30 days before onset of illness. No differences were noted between cases and controls in the degree of exposure to house dust mite-associated factors in the home, nor in the occurrence, density and species-specific prevalence of house dust mites in the home. Meadow voles exposed to house dust mites from the homes of patients did not develop serologic or pathologic evidence of infection due to rickettsiae in the spotted fever and typhus groups or Coxiella burnetii. Anti-mite-specific immunoglobulin E was not detected in serum specimens from cases or controls. Results from this study do not support hypotheses suggesting that the development of Kawasaki syndrome is associated with exposure to application of carpet shampoo, house dust mites, or rickettsial infection.

Efficacy evaluation of a pollen blocker cream against dust-mite allergy: A multicenter, randomized, double-blind, placebo-controlled crossover trial.

PubMed

Li, Yanqing; Cheng, Lei; Chen, Xiaoning; Yang, Beibei; Wang, Dehui

2015-01-01

To further evaluate the efficacy and safety of a pollen blocker cream against dust-mite allergy. A multicenter, randomized, double-blind, placebo-controlled, crossover trial was conducted in a Chinese population. Patients diagnosed with perennial allergic rhinitis, sensitive to dust-mite allergy including Dermatophagoides farinae and Dermatophagoides pteronyssinus were randomly allocated to receive a pollen blocker cream or placebo, which was applied and spread evenly to the lower internal nose region three times daily for a total of 30 days. The primary outcome measurements for efficacy were total nasal symptom score (TNSS) and individual nasal symptom score (iNSS). Adverse events were also monitored. After application of a pollen blocker, the mean TNSS decreased from 23.1 to 13.8, the decrease of the pollen blocker group (9.3) was highly significant compared with the placebo group (5.2; p < 0.001). Similarly, the decreases in iNSSs (rhinorrhea, congestion, sneezing, and itching) between the pollen blocker group and the placebo group were also significant (p < 0.05). In addition, in adults, the pollen blocker led to a remarkably significant decrease in TNSS (9.5) compared with placebo (5.4; p < 0.001); in children, the pollen blocker led to a significant decrease in TNSS (8.6) compared with placebo (4.8; p < 0.05). No statistical difference was found in the incidence of adverse events between the two groups (p > 0.05), and no severe systematic reactions were observed. Pollen Blocker is a safe and effective alternative to the drugs for treatment of AR, especially for Chinese people allergic to dust-mite allergy.

Occurrence of polybrominated diphenyl ethers in floor and elevated surface house dust from Shanghai, China.

PubMed

Niu, Dong; Qiu, Yanling; Li, Li; Zhou, Yihui; Du, Xinyu; Zhu, Zhiliang; Chen, Ling; Lin, Zhifen

2018-04-24

House dust is the main source of human exposure to flame retardants by ingestion. This study investigated the occurrence of polybrominated diphenyl ethers (PBDEs) in indoor dust from 22 houses in Shanghai, China. House dust was separately collected from the floor and elevated furnishings surface (mostly between 0.5 and 2 m height) for comparison. The concentrations of ∑ 22 PBDEs ranged from 19.4 to 3280 ng/g (with a geometric mean of 203 ng/g) and from 55.1 to 792 ng/g (with a geometric mean of 166 ng/g) in floor dust (FD) and elevated surface dust (ESD), respectively. BDE-209 was the predominant congener, accounting for about 73.1% of total PBDE burdens. In terms of congener profiles, the comparison of FD and ESD revealed no significant differences except for the ratio of BDE-47/BDE-99. ESD samples displayed a ratio of BDE-47/BDE-99 very similar to commercial penta-BDE products DE-71 while the ratio in FD was exceptionally higher. Significant correlation was found between concentrations of commercial penta-BDE compositions in FD and ESD (p < 0.05). Except for some occasional values, PBDE levels in house dust exhibited temporal stability. Human exposure to PBDEs via dust ingestion was estimated. The highest daily intake of PBDEs was for toddlers by using 95th percentile concentrations of PBDEs via high dust ingestion in FD (23.07 ng/kg bw/day). About 20-fold difference in exposure estimates between toddlers and adults supports that toddlers are facing greater risk from indoor floor dust. Expectedly, this study highlighted the point that residents in Shanghai were exposed to low doses of PBDEs in house dust.

Dust Allergens within Rural Northern Rocky Mountain Residences.

PubMed

Weiler, Emily; Semmens, Erin; Noonan, Curtis; Cady, Carol; Ward, Tony

2015-01-23

To date, few studies have characterized allergens within residences located in rural areas of the northern Rocky Mountain region. In this study, we collected dust samples from 57 homes located throughout western Montana and northern Idaho. Dust samples were collected and later analyzed for dust mite allergens Der f 1 and Der p 1 , Group 2 mite allergens ( Der p 2 and Der f 2 ), domestic feline ( Fel d 1 ), and canine ( Can f 1 ). Indoor temperature and humidity levels were also measured during the sampling program, as were basic characteristics of each home. Dog (96%) and cat (82%) allergens were the most prevalent allergens found in these homes (even when a feline or canine did not reside in the home). Results also revealed the presence of dust mites. Seven percent (7%) of homes tested positive for Der p 1 , 19% of homes were positive for Der f 1 , and 5% of homes were positive for the Group 2 mite allergens. Indoor relative humidity averaged 27.0 ± 7.6% within the homes. Overall, humidity was not significantly associated with dust mite presence, nor was any of the other measured home characteristics. This study provides a descriptive assessment of indoor allergen presence (including dust mites) in rural areas of the northern Rocky Mountains, and provides new information to assist regional patients with reducing allergen exposure using in-home intervention strategies.

Polyfluoroalkyl chemicals in house dust

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kato, Kayoko; Calafat, Antonia M., E-mail: acalafat@cdc.gov; Needham, Larry L.

2009-07-15

We developed a high throughput analytical method using on-line solid phase extraction coupled with isotope dilution high-performance liquid chromatography-tandem mass spectrometry (on-line SPE-HPLC-MS/MS) to simultaneously determine the concentrations of 17 polyfluoroalkyl chemicals (PFCs) in house dust. The sample preparation includes dispersion of the dust samples in 0.1 M formic acid:MeOH (1:1), followed by agitation and filtration, addition of the isotope-labeled internal standard solution to the filtrate, and analysis by on-line SPE-HPLC-MS/MS. The limits of quantitation were <4.0 ng/g. The method accuracies ranged between 73.2% and 100.2% for the different analytes at two spike levels. We confirmed the validity of themore » method by analyzing 39 household dust samples collected in 2004. Of the 17 PFCs measured, 6 of them-perfluorobutane sulfonate (PFBuS), N-ethyl-perfluorooctane sulfonamide, 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid (Et-PFOSA-AcOH), 2-(N-methyl-perfluorooctane sulfonamido) ethanol (Me-PFOSA-EtOH), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS)-had detection frequencies >70%. We detected PFOS, PFBuS, and PFHxS at the highest median concentration, followed by Et-PFOSA-AcOH and Me-PFOSA-EtOH.« less

Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small 'laying hen' cages.

PubMed

Lesna, Izabela; Sabelis, Maurice W; van Niekerk, Thea G C M; Komdeur, Jan

2012-12-01

To assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in cages, each with 2-3 laying hens, initially 300 poultry red mites and later the release of 1,000 predators. These small-scale tests were designed to prevent mite escape from the cages and they were carried out in three replicates at each of three temperature regimes: 26, 30 (constant day and night) and 33-25 °C (day-night cycle). After 6 weeks total population sizes of poultry red mites and predatory mites were assessed. For the temperature regimes of 26 and 33/25 °C S. scimitus reduced the poultry red mite population relative to the control experiments by a factor 3 and 30, respectively, and A. casalis by a factor of 18 and 55, respectively. At 30 °C the predators had less effect on red mites, with a reduction of 1.3-fold for S. scimitus and 5.6-fold for A. casalis. This possibly reflected hen manure condition or an effect of other invertebrates in the hen feed. Poultry red mite control was not negatively affected by temperatures as high as 33 °C and was always better in trials with A. casalis than in those with S. scimitus. In none of the experiments predators managed to eradicate the population of poultry red mites. This may be due to a prey refuge effect since most predatory mites were found in and around the manure tray at the bottom of the cage, whereas most poultry red mites were found higher up in the cage (i.e. on the walls, the cover, the perch, the nest box and the food box). The efficacy of applying predatory mites in the poultry industry may be promoted by reducing this refuge effect, boosting predatory mite populations using alternative prey and prolonged predator release devices. Biocontrol success, however, will strongly depend on how the poultry is

Detection of Dermatophagoides farinae in the dust of air conditioning filters.

PubMed

Liu, Zhigang; Bai, Yu; Ji, Kunmei; Liu, Xiaoyu; Cai, Chengyu; Yu, Haiqiong; Li, Meng; Bao, Ying; Lian, Yuyin; Gao, Bo

2007-01-01

The allergenic dust mite species Dermatophagoides pteronyssinus and Dermatophagoides farinae generally inhabit warm moist environments. This study tested the hypothesis that these allergenic species may thrive in air conditioner filters. A year-long investigation of the dust mite population densities and species identities living in air conditioner filters in Shenzhen City in Southern China was performed. Additional data describing the levels of major dust mite allergen proteins from samples collected in July and August 2004 were analyzed. Genetic polymorphism analysis of Der f 1 and Der f 2 genes in the collected animals was also conducted. Our investigation revealed that larval dust mites started to grow in March, from which time their populations proceeded to steadily increase until reaching their population zenith in July and August. The dust mite populations decreased sharply in October and live dust mites were no longer observed in the winter. Among the mites collected in July and August, 30.1 and 25.8% were of the species D. farinae. The concentration of Der f 1 was 3.04 +/- 1.75 and 3.21 +/- 1.84 microg/g dust in July and August, respectively, and that of Der f 2 was 2.15 +/- 0.82 and 2.04 +/- 1.15 microg/g dust. Four types of Der f 1 and 5 types of Der f 2 cDNA sequences were cloned from collected Der f mites. Their sequences were highly homologous with those previously published in GenBank (No. AB034946.1 and No. AB195580.1). This research demonstrated that Der f allergens exist in the dust of air conditioner filters in this area.

Organophosphate Flame Retardants in House Dust from South China and Related Human Exposure Risks.

PubMed

Tan, Hongli; Peng, Changfeng; Guo, Ying; Wang, Xiaodong; Wu, Yan; Chen, Da

2017-09-01

House dust associated with organic pollutants is not only a potential source of pollutants to the outdoor environment, but also a source to human exposure. The present study investigated the occurrence and concentrations of organophosphate flame retardants (OPFRs) in house dust collected from South China dwellings (n = 20). The results revealed a universal presence of most target OPFRs in house dust, with concentrations of ΣOPFRs ranging from 2.06 to 19.95 μg/g. The median concentration of ΣOPFR (9.20 μg/g) was one order of magnitude greater than that of polybrominated diphenyl ethers (0.80 μg/g). The composition of OPFR chemicals in house dust was dominated by chlorinated OPFRs, such as tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and tris(1-chloro-2-propyl) phosphate (TCPP). This compositional pattern was different from what has been reported in indoor dust from many other countries, where tris(2-butoxyethyl) phosphate (TBEP) was generally dominant. The daily intake of OPFRs by adults was estimated to be 1.6 and 4.2 ng/kg body weight/day under average and high exposure scenarios, respectively, and 31.7 and 127 ng/kg body weight/day for toddlers.

The minor house dust mite allergen Der p 13 is a fatty acid-binding protein and an activator of a TLR2-mediated innate immune response.

PubMed

Satitsuksanoa, P; Kennedy, M; Gilis, D; Le Mignon, M; Suratannon, N; Soh, W T; Wongpiyabovorn, J; Chatchatee, P; Vangveravong, M; Rerkpattanapipat, T; Sangasapaviliya, A; Piboonpocanun, S; Nony, E; Ruxrungtham, K; Jacquet, A

2016-10-01

The house dust mite (HDM) allergen Der p 13 could be a lipid-binding protein able to activate key innate signaling pathways in the initiation of the allergic response. We investigated the IgE reactivity of recombinant Der p 13 (rDer p 13), its lipid-binding activities, and its capacity to stimulate airway epithelium cells. Purified rDer p 13 was characterized by mass spectrometry, circular dichroism, fluorescence-based lipid-binding assays, and in silico structural prediction. IgE-binding activity and allergenic potential of Der p 13 were examined by ELISA, basophil degranulation assays, and in vitro airway epithelial cell activation assays. Protein modeling and biophysical analysis indicated that Der p 13 adopts a β-barrel structure with a predominately apolar pocket representing a potential binding site for hydrophobic ligands. Fluorescent lipid-binding assays confirmed that the protein is highly selective for ligands and that it binds a fatty acid with a dissociation constant typical of lipid transporter proteins. The low IgE-binding frequency (7%, n = 224) in Thai HDM-allergic patients as well as the limited propensity to activate basophil degranulation classifies Der p 13 as a minor HDM allergen. Nevertheless, the protein with its presumptively associated lipid(s) triggered the production of IL-8 and GM-CSF in respiratory epithelial cells through a TLR2-, MyD88-, NF-kB-, and MAPK-dependent signaling pathway. Although a minor allergen, Der p 13 may, through its lipid-binding capacity, play a role in the initiation of the HDM-allergic response through TLR2 activation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mast cell-dependent IL-33/ST2 signaling is protective against the development of airway hyperresponsiveness in a house dust mite mouse model of asthma.

PubMed

Zoltowska Nilsson, A M; Lei, Y; Adner, M; Nilsson, G P

2018-03-01

Interleukin-33 (IL-33) and its receptor ST2 have been influentially associated with the pathophysiology of asthma. Due to the divergent roles of IL-33 in regulating mast cell functions, there is a need to further characterize IL-33/ST2-dependent mast cell responses and their significance in the context of asthma. This study aimed to investigate how IL-33/ST2-dependent mast cell responses contribute to the development of airway hyperresponsiveness (AHR) and airway inflammation in a mouse model of house dust mite (HDM)-induced asthma. Mast cell-deficient C57BL/6-Kit W-sh (Wsh) mice engrafted with either wild-type (Wsh + MC-WT) or ST2-deficient bone marrow-derived mast cells (Wsh + MC-ST2KO) were exposed to HDM delivered intranasally. An exacerbated development of AHR in response to HDM was seen in Wsh + MC-ST2KO compared with Wsh + MC-WT mice. The contribution of this IL-33/ST2-dependent mast cell response to AHR seems to reside within the smaller airways in the peripheral parts of the lung, as suggested by the isolated yet marked effect on tissue resistance. Considering the absence of a parallel increase in cellular inflammation in bronchoalveolar lavage fluid (BALF) and lung, the aggravated AHR in Wsh + MC-ST2KO mice seems to be independent of cellular inflammation. We observed an association between the elevated AHR and reduced PGE 2 levels in BALF . Due to the protective properties of PGE 2 in airway responses, it is conceivable that IL-33/ST2-dependent mast cell induction of PGE 2 could be responsible for the dampening effect on AHR. In conclusion, we reveal that IL-33/ST2-dependent mast cell responses can have a protective, rather than causative role, in the development of AHR.

The development of allergic inflammation in a murine house dust mite asthma model is suppressed by synbiotic mixtures of non-digestible oligosaccharides and Bifidobacterium breve M-16V.

PubMed

Verheijden, K A T; Willemsen, L E M; Braber, S; Leusink-Muis, T; Jeurink, P V; Garssen, J; Kraneveld, A D; Folkerts, G

2016-04-01

The incidence and severity of allergic asthma is rising, and novel strategies to prevent or treat this disease are needed. This study investigated the effects of different mixtures of non-digestible oligosaccharides combined with Bifidobacterium breve M-16V (BB) on the development of allergic airway inflammation in an animal model for house dust mite (HDM)-induced allergic asthma. BALB/c mice were sensitized intranasally (i.n.) with HDM and subsequently challenged (i.n.) with PBS or HDM while being fed diets containing different oligosaccharide mixtures in combination with BB or an isocaloric identical control diet. Bronchoalveolar lavage fluid (BALF) inflammatory cell influx, chemokine and cytokine concentrations in lung homogenates and supernatants of ex vivo HDM-restimulated lung cells were analyzed. The HDM-induced influx of eosinophils and lymphocytes was reduced by the diet containing the short-chain and long-chain fructo-oligosaccharides and BB (FFBB). In addition to the HDM-induced cell influx, concentrations of IL-33, CCL17, CCL22, IL-6, IL-13 and IL-5 were increased in supernatants of lung homogenates or BALF and IL-4, IFN-γ and IL-10 were increased in restimulated lung cell suspensions of HDM-allergic mice. The diet containing FFBB reduced IL-6, IFN-γ, IL-4 and IL-10 concentrations, whereas the combination of galacto-oligosaccharides and long-chain fructo-oligosaccharides with BB was less potent in this model. These findings show that synbiotic dietary supplementation can affect respiratory allergic inflammation induced by HDM. The combination of FFBB was most effective in the prevention of HDM-induced airway inflammation in mice.

Occupational asthma and IgE sensitization to grain dust.

PubMed Central

Park, H. S.; Nahm, D. H.; Suh, C. H.; Kwon, O. Y.; Kim, K. S.; Lee, S. W.; Chung, H. K.

1998-01-01

To evaluate type I hypersensitivity to grain dust (GD), its prevalence and relationship to respiratory dysfunction, we studied clinical and immunologic features, including skin prick tests (SPT), serum specific IgE, and bronchoprovocation tests of 43 employees working in the animal feed industry. To further characterize IgE-mediated reaction, SDS-PAGE and electroblot studies were performed. Our survey revealed that 15 (34.9%) subjects had work-related skin response (> or =2+ of A/H ratio) to GD, thirteen (30.2%) had high specific IgE antibody against GD. The specific IgE antibody was detected more frequently in symptomatic workers (40%) than in asymptomatic workers (11%). Significant association was found between specific IgE antibody and atopy or smoking (p<0.05). The ELISA inhibition test of GD revealed significant inhibitions by GD extract and minimal inhibitions by the house dust mite, storage mite and corn dust. Immunoblot analysis showed 8 IgE binding components within GD ranging from 13.5 to 142.5 kDa. Two bands (13.5, 33 kDa) were bound to the IgE from more than 50% of the 14 sera tested. In conclusion, these findings suggest that GD inhalation could induce IgE-mediated bronchoconstriction in exposed workers. PMID:9681805

Occupational asthma and IgE sensitization to grain dust.

PubMed

Park, H S; Nahm, D H; Suh, C H; Kwon, O Y; Kim, K S; Lee, S W; Chung, H K

1998-06-01

To evaluate type I hypersensitivity to grain dust (GD), its prevalence and relationship to respiratory dysfunction, we studied clinical and immunologic features, including skin prick tests (SPT), serum specific IgE, and bronchoprovocation tests of 43 employees working in the animal feed industry. To further characterize IgE-mediated reaction, SDS-PAGE and electroblot studies were performed. Our survey revealed that 15 (34.9%) subjects had work-related skin response (> or =2+ of A/H ratio) to GD, thirteen (30.2%) had high specific IgE antibody against GD. The specific IgE antibody was detected more frequently in symptomatic workers (40%) than in asymptomatic workers (11%). Significant association was found between specific IgE antibody and atopy or smoking (p<0.05). The ELISA inhibition test of GD revealed significant inhibitions by GD extract and minimal inhibitions by the house dust mite, storage mite and corn dust. Immunoblot analysis showed 8 IgE binding components within GD ranging from 13.5 to 142.5 kDa. Two bands (13.5, 33 kDa) were bound to the IgE from more than 50% of the 14 sera tested. In conclusion, these findings suggest that GD inhalation could induce IgE-mediated bronchoconstriction in exposed workers.

Use of Monte Carlo analysis in a risk-based prioritization of toxic constituents in house dust.

PubMed

Ginsberg, Gary L; Belleggia, Giuliana

2017-12-01

Many chemicals have been detected in house dust with exposures to the general public and particularly young children of potential health concern. House dust is also an indicator of chemicals present in consumer products and the built environment that may constitute a health risk. The current analysis compiles a database of recent house dust concentrations from the United States and Canada, focusing upon semi-volatile constituents. Seven constituents from the phthalate and flame retardant categories were selected for risk-based screening and prioritization: diethylhexyl phthalate (DEHP), butyl benzyl phthalate (BBzP), diisononyl phthalate (DINP), a pentabrominated diphenyl ether congener (BDE-99), hexabromocyclododecane (HBCDD), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and tris(2-chloroethyl) phosphate (TCEP). Monte Carlo analysis was used to represent the variability in house dust concentration as well as the uncertainty in the toxicology database in the estimation of children's exposure and risk. Constituents were prioritized based upon the percentage of the distribution of risk results for cancer and non-cancer endpoints that exceeded a hazard quotient (HQ) of 1. The greatest percent HQ exceedances were for DEHP (cancer and non-cancer), BDE-99 (non-cancer) and TDCIPP (cancer). Current uses and the potential for reducing levels of these constituents in house dust are discussed. Exposure and risk for other phthalates and flame retardants in house dust may increase if they are used to substitute for these prioritized constituents. Therefore, alternative assessment and green chemistry solutions are important elements in decreasing children's exposure to chemicals of concern in the indoor environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Levels of phthalate esters in settled house dust from urban dwellings with young children in Nanjing, China

NASA Astrophysics Data System (ADS)

Zhang, Qi; Lu, Xiao-Mei; Zhang, Xiao-Ling; Sun, Yong-Gang; Zhu, Dong-Mei; Wang, Bing-Ling; Zhao, Ren-Zheng; Zhang, Zheng-Dong

2013-04-01

To investigate the levels and possible determinants of phthalate esters (PEs) in settled house dust from urban dwellings with young children, dust was collected from 215 urban houses in Nanjing, China, and 145 outdoor settled dust samples were collected nearby. Six PEs were measured by gas chromatography/mass spectrometry. All PEs were detected in the dust from approximately 90% of the houses, with the exception of dioctyl phthalate (DOP), which had only a 59% detection rate. Di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DBP) were the most abundant PEs, with geometric means of 110 and 16.4 μg g-1, respectively, and maximal concentrations 9950 and 2150 μg g-1. Factor analysis showed that DBP, DEHP and benzyl butyl phthalate (BBP) might come from the same source and were significantly influenced by the use of solid-wood floor wax. High BBP, DEHP, DOP and total PE levels were associated with indices of dampness, and high DOP was associated with humidifier use. In conclusion, six PEs are ubiquitous in urban settled house dust in Nanjing, China, and both plastic materials and cosmetic and personal care products are important sources. Flooring material, dampness and humidifier use potentially influence house dust PE levels.

Exposure to phthalates in house dust and associated allergies in children aged 6-12years.

PubMed

Ait Bamai, Yu; Araki, Atsuko; Kawai, Toshio; Tsuboi, Tazuru; Saito, Ikue; Yoshioka, Eiji; Cong, Shi; Kishi, Reiko

2016-11-01

Phthalates are widely used as plasticizers in household products. Several studies have reported an association between phthalate exposure and an increased risk of allergies. The present study estimated phthalate exposure in children aged 6-12years and assessed potential correlations with allergies. House dust samples were collected from floors and multi-surface objects >35cm above the floor. Urine samples were collected from the first morning void of the day. Daily phthalate intake (DI dust and DI) was estimated using both house dust and urinary metabolite concentrations. Exposure to di-2-ethylhexyl phthalate (DEHP) in floor dust was associated with parental-reported rhino-conjunctivitis. After stratification by gender, this trend was found to only occur in boys. Furthermore, urinary mono-isobutyl phthalate was inversely associated with parental-reported wheeze in boys. DI dust of benzyl butyl phthalate (BBzP) and DEHP were significantly correlated with DI_BBzP and DI_DEHP, respectively. These correlations were stronger with floor than with multi-surface dust. Our results suggest that, among Japanese children, house dust from low surfaces, such as living room floors, might play a meaningful role in the indoor environmental exposure pathway for BBzP and DEHP. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radiocesium contamination in house dust within evacuation areas close to the Fukushima Daiichi nuclear power plant.

PubMed

Shinohara, Naohide; Yoshida-Ohuchi, Hiroko

2018-05-01

Outdoor decontamination efforts have been ongoing since the Fukushima Daiichi nuclear power plant (FDNPP) accident; however, little is known about indoor contamination. Therefore, house dust was sampled based on particle size in 21 wooden buildings (19 residential houses and 2 community centers) within the evacuation area close to the FDNPP, Fukushima Prefecture, Japan. Activities of radiocesium ( 137 Cs) per gram of house dust increased with decreasing particle size (mean: 6.1 × 10 3 , 2.6 × 10 3 , 1.6 × 10 3 , 7.5 × 10 2 , 5.0 × 10 2 , and 4.6 × 10 2  Bq/g for <4-20, 20-63, 63-180, 180-500, 500-1000, and 1000-2000 μm, respectively). The 137 Cs concentrations in house dust were inversely related to the square of distance from the FDNPP for <4-1000 μm particles. From the results of the multiple linear regression analysis, distance from the FDNPP and direction from the FDNPP (northwest) were significantly related to the radioactivity of house dust. It was found that 19%, 33%, and 48% of 137 Cs in house dust were extracted in water, 1 M HCl, and not extracted, respectively. Considering the bioaccessibility and assuming a 20 mg/day daily intake of house dust, the daily doses would be 7.2 Bq/day (mean) and 18 Bq/day (95th percent quantile). These results provide valuable insight into indoor radioactive Cs contamination in the area around the FDNPP and possible oral exposure to indoor radioactive Cs after returning home. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Predominance of Gram-positive bacteria in house dust in the low-allergy risk Russian Karelia.

PubMed

Pakarinen, Jaakko; Hyvärinen, Anne; Salkinoja-Salonen, Mirja; Laitinen, Sirpa; Nevalainen, Aino; Mäkelä, Mika J; Haahtela, Tari; von Hertzen, Leena

2008-12-01

Simple living conditions and farming environment have been associated with reduced risk for allergic diseases such as atopy and asthma but the factors responsible for this effect remain unresolved. We examined the bacterial composition of house dusts obtained from Finnish and Russian Karelia, two adjacent areas with high and low occurrence of atopic diseases respectively. Two dust mixes, both composed of 10 randomly selected dust samples from 349 Finnish and 417 Russian Karelian households were studied for bacterial biomarkers (DNA, Limulus-active endotoxin, 3-OH fatty acids, muramic acid) and for 16S rRNA gene sequences. Overall, the DNA cloning revealed more taxons (94 different genera) of dustborne bacteria than seen in any previous study on residential environments. Majority (67%) of the bacterial DNA clones in house dust from the low-allergy Russian Kareliarepresented Gram-positive bacteria (Firmicutes and Actinobacteria), predominantly Staphylococcaceae and Corynebacteriaceae. Russian Karelian dust showed up to 20-fold higher contents of muramic acid (marker of Gram-positive bacteria) and a sevenfold higher number of clones of animal-associated species, whereas in Finnish Karelian dust Gram-negatives (mainly Proteobacteria) predominated. Clones of plant-associated bacterial species and of chloroplast, indicating plant biomass, were more numerous in Finnish than in Russian Karelian dust. In conclusion, this study revealed major disparities between Finnish and Russian house dusts. The higher bacterial content and the predominance of Gram-positive bacteria in Russian dust may have implications for occurrence of atopy.

[Fauna and biology of the Pyroglyphidae of Poland].

PubMed

Solarz, K

1995-01-01

5 valid species of pyroglyphid mites are actually known in Polish fauna. It should be stressed that the knowledge of their occurrence in house-dust, bird nests and other habitats is still poor. The most common pyroglyphid house-dust mites, Dermatophagoides pteronyssinus, D. farinae and Euroglyphus maynei, were found in samples of dust from houses (Warszawa, Bydgoszcz, Upper Silesia), hospitals (Katowice, Sosnowiec), libraries (Sosnowiec) and port buildings (Gdynia). The both species of the genus Dermatophagoides were also found in house-dust samples in Poznań and Poznań vicinity, whereas E. maynei and D. pteronyssinus--occasionally in stored herbs in Grudziadz. Moreover, Gymnoglyphus longior was reported from house-dust (Tarnowskie Góry, Upper Silesia), debris from a byre in Lesko and from barn litter in Solarnia near Lubliniec, while Hirstia passericola was found in byre debris in Lesko. It seems that D. pteronyssinus and D. farinae are common in house-dust all over the country. The following pyroglyphid mite species--D. pteronyssinus, H. passericola, G. longior--are reported from nests of birds in Poland.

TH17-induced neutrophils enhance the pulmonary allergic response following BALB/c exposure to house dust mite allergen and fine particulate matter from California and China.

PubMed

Zhang, Jingjing; Fulgar, Ciara C; Mar, Tiffany; Young, Dominique E; Zhang, Qi; Bein, Keith J; Cui, Liangliang; Castañeda, Alejandro; Vogel, Christoph F A; Sun, Xiaolin; Li, Wei; Smiley-Jewell, Suzette; Zhang, Zunzhen; Pinkerton, Kent E

2018-05-28

Asthma is a global and increasingly prevalent disease. According to the World Health Organization, approximately 235 million people suffer from asthma. Studies suggest that fine particulate matter (PM2.5) can induce innate immune responses, promote allergic sensitization, and exacerbate asthmatic symptoms and airway hyper-responsiveness. Recently, severe asthma and allergic sensitization have been associated with T-helper cell type 17 (TH17) activation. Few studies have investigated the links between PM2.5 exposure, allergic sensitization, asthma, and TH17 activation. This study aimed to determine whether 1) low-dose extracts of PM2.5 from California (PMCA) or China (PMCH) enhance allergic sensitization in mice following exposure to house dust mite (HDM) allergen; 2) eosinophilic or neutrophilic inflammatory responses result from PM and HDM exposure; and 3) TH17-associated cytokines are increased in the lung following exposure to PM and/or HDM.Ten-week old male BALB/c mice (n = 6-10/group) were intranasally instilled with phosphate-buffered saline (PBS), PM+PBS, HDM, or PM+HDM, on Days 1, 3, and 5 (sensitization experiments), and PBS or HDM on Days 12-14 (challenge experiments). Pulmonary function, bronchoalveolar lavage cell differentials, plasma immunoglobulin (Ig) protein levels, and lung tissue pathology, cyto-/chemo-kine proteins, and gene expression were assessed on Day 15.Results indicated low-dose PM2.5 extracts can enhance allergic sensitization and TH17-associated responses. While PMCA+HDM significantly decreased pulmonary function, and significantly increased neutrophils, Igs, and TH17-related protein and gene levels compared to HDM, there were no significant differences between HDM and PMCH+HDM treatments. This may result from greater copper and oxidized organic content in PMCA versus PMCH.

Associations between brominated flame retardants in house dust and hormone levels in men

PubMed Central

Johnson, Paula I.; Stapleton, Heather M.; Mukherjee, Bhramar; Hauser, Russ; Meeker, John D.

2013-01-01

Brominated flame retardants (BFRs) are used in the manufacture of a variety of materials and consumer products in order to meet fire safety standards. BFRs may persist in the environment and have been detected in wildlife, humans and indoor dust and air. Some BFRs have demonstrated endocrine and reproductive effects in animals, but human studies are limited. In this exploratory study, we measured serum hormone levels and flame retardant concentrations [31 polybrominated diphenyl ether (PBDE) congeners and 6 alternate flame retardants] in house dust from men recruited through a US infertility clinic. PBDE congeners in dust were grouped by commercial mixtures (i.e. penta-, octaand deca-BDE). In multivariable linear regression models adjusted by age and body mass index (BMI), significant positive associations were found between house dust concentrations of pentaBDEs and serum levels of free T4, total T3, estradiol, and sex hormone binding globulin (SHBG), along with an inverse association with follicle stimulating hormone (FSH). There were also positive associations of octaBDE concentrations with serum free T4, thyroid stimulating hormone (TSH), luteinizing hormone (LH) and testosterone and an inverse association of decaBDE concentrations with testosterone. Hexabromocyclododecane (HBCD) was associated with decreased SHBG and increased free androgen index. Dust concentrations of bis-tribromophenoxyethane (BTBPE) and tetrabromo-diethylhexylphthalate (TBPH) were positively associated with total T3. These findings are consistent with our previous report of associations between PBDEs (BDE 47, 99 and 100) in house dust and hormone levels in men, and further suggest that exposure to contaminants in indoor dust may be leading to endocrine disruption in men. PMID:23333513

Feather and nest mites of two common resident birds in two ecologically different Egyptian governorates.

PubMed

Morsy, T A; Mazyad, S A; Younis, M S

1999-08-01

The study of the role played by birds in the distribution of various bacterial, viral and parasitic infections is increasingly from year to year, taking into consideration the flying ability of birds and their migration for food and vital processes. Two of the common Egyptian resident birds, house sparrow (Passer d. niloticus) and laughing dove (Streptopelia s. aegyptiaca) were chosen to study their mite fauna. The overall mite index was 4.74 on the house sparrow and 7.22 on the laughing dove. As to mites, a total of 31 species belonging to 23 genera, 17 families and 3 suborders were collected. The common mites on both types of birds were 22 species. Three species only on house sparrow, and six species only on laughing dove. The house sparrow served host for 25 mite species and the laughing dove served host for 28 mite species. The infestation rates of mites on house sparrow ranged between 1.11% to 23.33% and 0.21% to 34.54% in Sharkia and Qalyobia governorates respectively. For laughing dove, the mite infestation rates ranged between 0.82% to 50% and 3.45% to 55.17% for both governorates respectively. Some of the collected mites have medical and/or veterinary importance. The whole results were discussed.

Investigating A Novel Flame Retardant Known as V6: Measurements in Baby Products, House Dust and Car Dust

PubMed Central

Fang, Mingliang; Webster, Thomas F.; Gooden, David; Cooper, Ellen M.; McClean, Michael D.; Carignan, Courtney; Makey, Colleen; Stapleton, Heather M.

2013-01-01

With the phase-out of polybrominated diphenyl ether (PBDE) flame retardants, the use of new and alternate flame retardants has been increasing. 2,2-bis(chloromethyl)propane-1,3-diyltetrakis(2-chloroethyl) bisphosphate, known as V6, is a flame retardant applied to polyurethane foam commonly found in furniture and automobile foam. However, to the authors’ knowledge, no research has been conducted on V6 levels in the environment. The intention of this study was to measure the concentration of V6 in foam collected from baby products where it was recently detected, and measure levels in dust samples collected from homes and automobiles in the Boston, MA area. To accomplish this a pure V6 commercial standard was purchased from a Chinese manufacturer and purified (> 98%). An analytical method to measure V6 in dust samples using liquid chromatography tandem mass spectrometry (LC/MS-MS) was developed. Extraction was conducted using Accelerated Solvent Extraction (ASE) and extracts were purified using an ENVI-Florisil SPE column (500 mg, 3mL). V6 was measured in foam samples collected from baby products with a concentration ranging from 24,500,000 to 59,500,000 ng/g of foam (n = 12, average ± sd: 46,500,000 ± 12,000,000 ng/g; i.e., on average, 4.6 % of the foam mass was V6). V6 was also detected in 19 of 20 car dust samples and 14 of 20 house dust samples analyzed. The concentration of V6 in the house dust ranged from < 5 ng/g to 1,110 ng/g with a median of 12.5 ng/g, and < 5 ng/g to 6,160 ng/g in the car dust with a median of 103.0 ng/g. Concentrations in car dust were significantly higher than the house dust, potentially indicating higher use of V6 in automobiles compared to products found in the home. Furthermore, tris (2-chloroethyl) phosphate (TCEP), a known carcinogen, was found in the V6 commercial mixture (14% by weight) as an impurity and was consistently detected with V6 in the foam samples analyzed. A significant correlation was also observed between V6 and

POLYBROMINATED DIPHENYL ETHERS IN HOUSE DUST AND CLOTHES DRYER LINT

EPA Science Inventory

Polybrominated diphenyl ether (PBDE) flame retardants are now considered ubiquitous and persistent pollutants. Few studies have examined the concentrations of these chemicals in the home and here we report measurements of PBDEs in house dust samples collected from the Washington...

[Effect of 1-year specific immunotherapy with standardized house dust mite vaccine on mild to moderate allergic asthmatic patients].

PubMed

Wang, Hong-yu; Lin, Xiao-ping; Hao, Chuang-li; Zhang, Chun-qing; Sun, Bao-qing; Zheng, Jin-ping; Chen, Ping; Sheng, Jin-yun; Wu, Adrian; Zhong, Nan-shan

2006-10-01

To evaluate the clinical efficacy and safety of specific immunotherapy (SIT) with standardized house dust mite (HDM) vaccine on allergic asthmatic patients. The investigation was a multicentre, randomized, double-blind, placebo-controlled clinical study. 132 patients with mild to moderate asthma who were allergic to HDM, recruited from three hospitals of China (The First Affiliated Hospital of Guangzhou Medical College, Shenyang General Military Hospital, Suzhou Children's Hospital), were randomly allocated to the active group (n = 66) or the control group (n = 66) respectively. The active group received SIT with a standardized depot Dermatophagoides pteronyssinus (Der p) extract absorbed to aluminium hydroxide (Alutard SQ, ALK-Abelló, Denmark), while the control group received a placebo containing histamine dihydrochloride by subcutaneous injections for 1 year. Treatment of each group was started from the initial concentration. Updosing was performed with weekly injections from four 10-fold dose-increase vials (active group: 100, 1,000, 10,000, 100,000 SQ-U/ml, control group: 0.01, 0.1, 1.0, 10 microg/ml. 100,000 SQ-U/ml of Der p extract contains 9.8 microg/ml of the majoy allergen Der p1). The single-dose was injected weekly with 0.2, 0.4, 0.8 ml of each concentration in turn from the preceding 3 vials, totally for 9 weeks. Subsequently, the dose with 0.1, 0.2, 0.4, 0.6, 0.8 ml of the highest concentration was injected weekly from the 10th-14th week and a maintenance dose with 1 ml was reached at the 15th week. The dosing interval was then gradually increased to 2, 4, 6 weeks until the end of the first 26-weeks updosing phase (phase I, H(1)). Thereafter, the dosing continued at 6-week intervals for maintenance phase (phase II, H(2)) till the end of the complete treatment. The patient was observed for at least 30 minutes in the clinic after each injection. A total of 132 subjects were randomized and 129 subjects (64 in the active group, 65 in the control group

Comparison of Gastric versus Gastrointestinal PBET Extractions for Estimating Oral Bioaccessibility of Metals in House Dust

PubMed Central

Boros, Kristina; Fortin, Danielle; Jayawardene, Innocent; Chénier, Marc; Levesque, Christine; Rasmussen, Pat E.

2017-01-01

Oral bioaccessibility estimates for six metals which are prevalent as contaminants in Canada (zinc, lead, cadmium, copper, nickel, and chromium) are investigated for house dust using the simple gastric phase versus the two-phase physiologically-based extraction technique (PBET). The purpose is to determine whether a complete gastrointestinal (GI) assay yields a more conservative (i.e., higher) estimate of metal bioaccessibility in house dust than the gastric phase alone (G-alone). The study samples include household vacuum dust collected from 33 homes in Montreal, Canada, plus four certified reference materials (NIST 2583, NIST 2584, NIST 2710 and NIST 2710a). Results indicate that percent bioaccessibilities obtained using G-alone are generally greater than or equivalent to those obtained using the complete GI simulation for the six studied metals in house dust. Median bioaccessibilities for G-alone/GI in household vacuum dust samples (n = 33) are 76.9%/19.5% for zinc, 50.4%/6.2% for lead, 70.0%/22.4% for cadmium, 33.9%/30.5% for copper and 28.5%/20.7% for nickel. Bioaccessible chromium is above the detection limit in only four out of 33 samples, for which G-alone results are not significantly different from GI results (p = 0.39). It is concluded that, for the six studied metals, a simple G-alone extraction provides a conservative and cost-effective approach for estimating oral bioaccessibility of metals in house dust. PMID:28106788

Detection of Organophosphate Flame Retardants in Furniture Foam and US House Dust

PubMed Central

Stapleton, Heather M.; Klosterhaus, Susan; Eagle, Sarah; Fuh, Jennifer; Meeker, John D.; Blum, Arlene; Webster, Thomas F.

2009-01-01

Restrictions on the use of polybrominated diphenyl ethers (PBDEs) have resulted in the increased use of alternate flame retardant chemicals to meet flammability standards. However, it has been difficult to determine which chemical formulations are currently being used in high volumes to meet flammability standards since the use of flame retardant formulations in consumer products is not transparent (i.e. not provided to customers). To investigate chemicals being used as replacements for PentaBDE in polyurethane foam, we analyzed foam samples from 26 different pieces of furniture purchased in the United States primarily between 2003 and 2009 using gas chromatography mass spectrometry. Samples included foam from couches, chairs, mattress pads, pillows, and, in one case, foam from a sound proofing system of a laboratory grade dust sieve. Fifteen of the foam samples contained the flame retardant tris(1,3-dichloro-2-propyl) phosphate (TDCPP; 1–5% by weight), four samples contained tris(1-chloro-2-propyl) phosphate (TCPP; 0.5 –2.2 % by weight), one sample contained brominated chemicals found in a new flame retardant mixture called Firemaster 550 (4.2% by weight), and one foam sample collected from a futon likely purchased prior to 2004 contained PentaBDE (0.5% by weight). Due to the high frequency of detection of the chlorinated phosphate compounds in furniture foam, we analyzed extracts from 50 house dust samples collected between 2002 and 2007 in the Boston, MA area for TDCPP, TCPP, and another high volume use organophosphate-based flame retardant used in foam, triphenylphosphate (TPP). Detection frequencies for TDCPP and TPP in the dust samples were >96% and were log normally distributed, similar to observations for PBDEs. TCPP was positively detected in dust in only 24% of the samples, but detection was significantly limited by a co-elution problem. The geometric mean concentrations for TCPP, TDCPP and TPP in house dust were 570, 1890, and 7360 ng/g, respectively

Application of Synchrotron Microprobe Methods to Solid-Phase Speciation of Metals and Metalloids in House Dust

DOE Office of Scientific and Technical Information (OSTI.GOV)

S Walker; H Jamieson; P Rasmussen

2011-12-31

Determination of the source and form of metals in house dust is important to those working to understand human and particularly childhood exposure to metals in residential environments. We report the development of a synchrotron microprobe technique for characterization of multiple metal hosts in house dust. We have applied X-ray fluorescence for chemical characterization and X-ray diffraction for crystal structure identification using microfocused synchrotron X-rays at a less than 10 {micro}m spot size. The technique has been evaluated by application to archived house dust samples containing elevated concentrations of Pb, Zn, and Ba in bedroom dust, and Pb and Asmore » in living room dust. The technique was also applied to a sample of soil from the corresponding garden to identify linkages between indoor and outdoor sources of metals. Paint pigments including white lead (hydrocerussite) and lithopone (wurtzite and barite) are the primary source of Pb, Zn, and Ba in bedroom dust, probably related to renovation activity in the home at the time of sampling. The much lower Pb content in the living room dust shows a relationship to the exterior soil and no specific evidence of Pb and Zn from the bedroom paint pigments. The technique was also successful at confirming the presence of chromated copper arsenate treated wood as a source of As in the living room dust. The results of the study have confirmed the utility of this approach in identifying specific metal forms within the dust.« less

Time-Based Measurement of Personal Mite Allergen Bioaerosol Exposure over 24 Hour Periods

PubMed Central

Tovey, Euan R.; Liu-Brennan, Damien; Garden, Frances L.; Oliver, Brian G.; Perzanowski, Matthew S.; Marks, Guy B.

2016-01-01

Allergic diseases such as asthma and rhinitis are common in many countries. Globally the most common allergen associated with symptoms is produced by house dust mites. Although the bed has often been cited as the main site of exposure to mite allergens, surprisingly this has not yet been directly established by measurement due to a lack of suitable methods. Here we report on the development of novel methods to determine the pattern of personal exposure to mite allergen bioaerosols over 24-hour periods and applied this in a small field study using 10 normal adults. Air was sampled using a miniature time-based air-sampler of in-house design located close to the breathing zone of the participants, co-located with a miniature time-lapse camera. Airborne particles, drawn into the sampler at 2L/min via a narrow slot, were impacted onto the peripheral surface of a disk mounted on the hour-hand of either a 12 or 24 hour clock motor. The impaction surface was either an electret cloth, or an adhesive film; both novel for these purposes. Following a review of the time-lapse images, disks were post-hoc cut into subsamples corresponding to eight predetermined categories of indoor or outdoor location, extracted and analysed for mite allergen Der p 1 by an amplified ELISA. Allergen was detected in 57.2% of the total of 353 subsamples collected during 20 days of sampling. Exposure patterns varied over time. Higher concentrations of airborne mite allergen were typically measured in samples collected from domestic locations in the day and evening. Indoor domestic Der p 1 exposures accounted for 59.5% of total exposure, whereas total in-bed-asleep exposure, which varied 80 fold between individuals, accounted overall for 9.85% of total exposure, suggesting beds are not often the main site of exposure. This study establishes the feasibility of novel methods for determining the time-geography of personal exposure to many bioaerosols and identifies new areas for future technical

Time-Based Measurement of Personal Mite Allergen Bioaerosol Exposure over 24 Hour Periods.

PubMed

Tovey, Euan R; Liu-Brennan, Damien; Garden, Frances L; Oliver, Brian G; Perzanowski, Matthew S; Marks, Guy B

2016-01-01

Allergic diseases such as asthma and rhinitis are common in many countries. Globally the most common allergen associated with symptoms is produced by house dust mites. Although the bed has often been cited as the main site of exposure to mite allergens, surprisingly this has not yet been directly established by measurement due to a lack of suitable methods. Here we report on the development of novel methods to determine the pattern of personal exposure to mite allergen bioaerosols over 24-hour periods and applied this in a small field study using 10 normal adults. Air was sampled using a miniature time-based air-sampler of in-house design located close to the breathing zone of the participants, co-located with a miniature time-lapse camera. Airborne particles, drawn into the sampler at 2L/min via a narrow slot, were impacted onto the peripheral surface of a disk mounted on the hour-hand of either a 12 or 24 hour clock motor. The impaction surface was either an electret cloth, or an adhesive film; both novel for these purposes. Following a review of the time-lapse images, disks were post-hoc cut into subsamples corresponding to eight predetermined categories of indoor or outdoor location, extracted and analysed for mite allergen Der p 1 by an amplified ELISA. Allergen was detected in 57.2% of the total of 353 subsamples collected during 20 days of sampling. Exposure patterns varied over time. Higher concentrations of airborne mite allergen were typically measured in samples collected from domestic locations in the day and evening. Indoor domestic Der p 1 exposures accounted for 59.5% of total exposure, whereas total in-bed-asleep exposure, which varied 80 fold between individuals, accounted overall for 9.85% of total exposure, suggesting beds are not often the main site of exposure. This study establishes the feasibility of novel methods for determining the time-geography of personal exposure to many bioaerosols and identifies new areas for future technical

House dust as possible route of environmental exposure to cadmium and lead in the adult general population

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hogervorst, Janneke; Plusquin, Michelle; Vangronsveld, Jaco

2007-01-15

Contaminated soil particles and food are established routes of exposure. We investigated the relations between biomarkers of exposure to cadmium and lead, and the metal loading rates in house dust in the adult residents of an area with a soil cadmium concentration of >=3mg/kg (n=268) and a reference area (n=205). We determined the metal concentrations in house dust allowed to settle for 3 months in Petri dishes placed in the participants' bedrooms. The continuously distributed vegetable index was the first principal component derived from the metal concentrations in six different vegetables. The biomarkers of exposure (blood cadmium 9.2 vs. 6.2nmol/L;more » 24-h urinary cadmium 10.5 vs. 7.0nmol; blood lead 0.31 vs. 0.24{mu}mol/L), the loading rates of cadmium and lead in house dust (0.29 vs. 0.12 and 7.52 vs. 3.62ng/cm{sup 2}/92 days), and the vegetable indexes (0.31 vs. -0.44 and 0.13 vs. -0.29 standardized units) were significantly higher in the contaminated area. A two-fold increase in the metal loading rate in house dust was associated with increases (P<0.001) in blood cadmium (+2.3%), 24-h urinary cadmium (+3.0%), and blood lead (+2.0%), independent of the vegetable index and other covariates. The estimated effect sizes on the biomarkers of internal exposure were three times greater for house dust than vegetables. In conclusion, in the adult population, house dust is potentially an important route of exposure to heavy metals in areas with contaminated soils, and should be incorporated in the assessment of health risks.« less

Human exposure to per- and polyfluoroalkyl substances (PFASs) via house dust in Korea: Implication to exposure pathway.

PubMed

Tian, Zhexi; Kim, Seung-Kyu; Shoeib, Mahiba; Oh, Jeong-Eun; Park, Jong-Eun

2016-05-15

A wide range of per- and polyfluoroalkyl substances (PFASs), including fluorotelomer alcohols (FTOHs), perfluorooctane sulfonamidoethanols (FOSEs), perfluoroalkyl carboxylic acids (PFCAs), and perfluoroalkane sulfonic acids (PFSAs), were measured in fifteen house dust and two nonresidential indoor dust of Korea. Total concentrations of PFASs in house dust ranged from 29.9 to 97.6 ng g(-1), with a dominance of perfluorooctane sulfonic acid (PFOS), followed by 8:2 FTOH, N-Ethyl perfluorooctane sulfonamidoethanol (EtFOSE), perfluoroctanoic acid (PFOA). In a typical exposure scenario, the estimated daily intakes (EDIs) of total PFASs via house dust ingestion were 2.83 ng d(-1) for toddlers and 1.13 ng d(-1) for adults, which were within the range of the mean EDIs reported from several countries. For PFOA and PFOS exposure via house dust ingestion, indirect exposure (via precursors) was a minor contributor, accounting for 5% and 12%, respectively. An aggregated exposure (hereafter, overall-EDIs) of PFOA and PFOS occurring via all pathways, estimated using data compiled from the literature, were 53.6 and 14.8 ng d(-1) for toddlers, and 20.5 and 40.6 ng d(-1) for adults, respectively, in a typical scenario. These overall-EDIs corresponded to 82% (PFOA) and 92% (PFOS) of a pharmacokinetic model-based EDIs estimated from adults' serum data. Direct dietary exposure was a major contributor (>89% of overall-EDI) to PFOS in both toddlers and adults, and PFOA in toddlers. As for PFOA exposure of adults, however direct exposure via tap water drinking (37%) and indirect exposure via inhalation (22%) were as important as direct dietary exposure (41%). House dust-ingested exposure (direct+indirect) was responsible for 5% (PFOS in toddlers) and <1% (PFOS in adults, and PFOA in both toddlers and adults) of the overall-EDIs. In conclusion, house-dust ingestion was a minor contributor in this study, but should not be ignored for toddlers' PFOS exposure due to its significance in the

In vitro and field studies on the contact and fumigant toxicity of a neem-product (Mite-Stop) against the developmental stages of the poultry red mite Dermanyssus gallinae.

PubMed

Locher, Nina; Al-Rasheid, Khaled A S; Abdel-Ghaffar, Fathy; Mehlhorn, Heinz

2010-07-01

The acaricidal activity of the neem product MiteStop was investigated for its potential use as a botanical acaricide for the control of the poultry red mite Dermanyssus gallinae. This neem product is a special formulation of an extract of the seeds of the neem tree Azadirachta indica A. Juss. The efficacy was tested under laboratory conditions as well as in poultry houses. Four different methods of application were used in a filter paper bioassay to evaluate contact and vapour phase toxicity tests. The neem product proved to be already active in very small doses. In order to investigate the efficacy under field conditions, a poultry house was sprayed twice within a 7-day period using 1:33 and 1:50 diluted MiteStop. Cardboard traps were used to assess the mite population before, during and after the treatment. The mite population could be reduced by 89%. In a second poultry house, the spraying of defined areas with a 1:30, 1:33 or 1:50 dilution of the acaricide proved to be highly efficacious against all mite stages. Three other field trials proved that MiteStop is highly active against the red poultry mite. The most efficient dilution is 1:33 with tap water and spraying two or three times at intervals of 7 days.

Phthalates in dormitory and house dust of northern Chinese cities: Occurrence, human exposure, and risk assessment.

PubMed

Li, Hai-Ling; Song, Wei-Wei; Zhang, Zi-Feng; Ma, Wan-Li; Gao, Chong-Jing; Li, Jia; Huo, Chun-Yan; Mohammed, Mohammed O A; Liu, Li-Yan; Kannan, Kurunthachalam; Li, Yi-Fan

2016-09-15

Phthalates are widely used chemicals in household products, which severely affect human health. However, there were limited studies emphasized on young adults' exposure to phthalates in dormitories. In this study, seven phthalates were extracted from indoor dust that collected in university dormitories in Harbin, Shenyang, and Baoding, in the north of China. Dust samples were also collected in houses in Harbin for comparison. The total concentrations of phthalates in dormitory dust in Harbin and Shenyang samples were significantly higher than those in Baoding samples. The total geometric mean concentration of phthalates in dormitory dust in Harbin was lower than in house dust. Di-(2-ethylhexyl) phthalate (DEHP) was the most abundant phthalate in both dormitory and house dust. The daily intakes of the total phthalates, carcinogenic risk (CR) of DEHP, hazard index (HI) of di-isobutyl phthalate (DiBP), dibutyl phthalate (DBP), and DEHP were estimated, the median values for all students in dormitories were lower than adults who live in the houses. Monte Carlo simulation was applied to predict the human exposure risk of phthalates. HI of DiBP, DBP, and DEHP was predicted according to the reference doses (RfD) provided by the United States Environmental Protection Agency (U.S.EPA) and the reference doses for anti-androgenicity (RfD AA) developed by Kortenkamp and Faust. The results indicated that the risks of some students had exceeded the limitation, however, the measured results were not exceeded the limitation. Risk quotients (RQ) of DEHP were predicted based on China specific No Significant Risk Level (NSRL) and Maximum Allowable Dose Level (MADL). The predicted results of CR and RQ of DEHP suggested that DEHP could pose a health risk through intake of indoor dust. Copyright © 2016 Elsevier B.V. All rights reserved.

Elemental composition of airborne dust in the Shale Shaker House during an offshore drilling operation.

PubMed

Hansen, A B; Larsen, E; Hansen, L V; Lyngsaae, M; Kunze, H

1991-12-01

During 2 days of an offshore drilling operation in the North Sea, 16 airborne dust samples from the atmosphere of the Shale Shaker House were collected onto filters. During this operation, drilling mud composed of a water slurry of barite (BaSO4) together with minor amounts of additives, among them chrome lignosulphonate and chrome lignite, was circulated between the borehole and the Shale Shaker House. The concentration of airborne dust in the atmosphere was determined and the elemental composition of the particles analysed by both PIXE (proton-induced X-ray emission) and ICP-MS (inductively coupled plasma-mass spectrometry). The total amount of dust collected varied from 0.04 to 1.41 mg m-3 with barium (Ba) as the single most abundant element. The open shale shakers turned out to be the major cause of generation of dust from the solid components of the drilling mud.

Non-PBDE halogenated flame retardants in Canadian indoor house dust: sampling, analysis, and occurrence.

PubMed

Fan, Xinghua; Kubwabo, Cariton; Rasmussen, Pat E; Wu, Fang

2016-04-01

An analytical method was developed for the measurement of 18 novel halogenated flame retardants in house dust. Sample preparation was based on ultrasound-assisted solvent extraction and clean up with solid phase extraction (SPE). Sample extracts were analyzed by gas chromatography-mass spectrometry (GC/MS) operated in electron capture negative ion (ECNI) chemical ionization mode. Baseline data from 351 fresh (active) dust samples collected under the Canadian House Dust Study (CHDS) revealed that five out of 18 target chemicals were present with detection frequencies higher than 90 %. Median (range) concentrations for these five compounds were as follows: 104 (<1.5-13,000) ng/g for 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB), 8.5 (<1.7-2390) ng/g for 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), 10.2 (<1.7-430) ng/g for hexabromobenzene (HBB), 2.9 (<1.2-1410) ng/g for syn-dechlorane plus (syn-DP) and 5.6 (<1.9-1570) ng/g for anti-dechlorane plus (anti-DP). A comparison of two sampling methods in a subset of 40 homes showed significant positive correlations between samples of "active" dust and samples taken directly from the household vacuum cleaner for all target compounds having median values above their corresponding method detection limits (MDLs). In addition, the method was also applied to the analysis of the targeted compounds in National Institute of Standards and Technology (NIST) standard reference material (SRM 2585, organic contaminants in house dust). Results from the current study could contribute to the potential certification of target chemicals in SRM 2585.

Clinicopathologic findings, sensitivity to house dust mites and efficacy of milbemycin oxime treatment of dogs with Cheyletiella sp. infestation.

PubMed

White, S D; Rosychuk, R A; Fieseler, K V

2001-02-01

Twenty-three dogs with positive skin scrapings for Cheyletiella sp. were treated with milbemycin oxime using a protocol approximating 2 mg kg-1 orally once weekly for three weeks. Nineteen of these dogs belonged to a household of 41 dogs and two dogs were in households with one other dog. All in-contact dogs were treated. Pre-treatment intradermal skin tests showed positive reactions to D. farinae in 13 dogs and to D. pteronyssinus in 12 dogs; these became negative post-treatment in four and seven dogs, respectively. All dogs showed a dramatic reduction in clinical signs one week after the third treatment. Eighteen dogs no longer had mites on skin scrapings, three had dead mites and two had deformed eggs. Recurrence of clinical signs necessitated two additional courses of the protocol in the multiple dog household and for a dog receiving immunosuppressive treatment for pemphigus foliaceus. Possible adverse reactions to the milbemycin (vomiting, lethargy) were noted once in two dogs.

Lack of Association Between Dust Mite Sensitivity and Atopic Dermatitis.

PubMed

Silverberg, Jonathan Ian; Hanifin, Jon M; Law, Sandra; White, Kevin; Storrs, Frances J

2016-01-01

Dust mites (DMs) play a role in type I respiratory allergy. Studies relating to DM irritant versus immune reactions are somewhat conflicting in atopic dermatitis (AD). The aim of this study was to assess the diagnostic use of patch testing to DM in patients with AD and other dermatitides. We performed a prospective study of 323 adults recruited in a patch testing clinic. Patch testing antigens were DM extract (0.01%, 0.1%, 1%, 10%, and 20% in petrolatum; Chemotechnique) and/or 200 index of reactivity in petrolatum (Stallergenes). Patches were placed and read at 48 hours with delayed readings after 72 to 168 hours. There was no association of DM positivity with AD, asthma, hay fever, or demographic factors. There was no association of DM positivity with the clinical diagnosis or phenotype. The number of positive (+, ++, and +++) and doubtful reactions to Chemotechnique DM extract increased with higher concentrations. Positive reactions to DM had a morphological appearance characterized by numerous discrete erythematous papules and, rarely, papulovesicles. Positive reactions to Stallergenes DM 200 IR were infrequent and all weak reactions, similar to DM 0.01%. Patch testing to DM does not seem to have clinical use for determining the etiology of dermatitis.

Chemical speciation and bioaccessibility of lead in surface soil and house dust, Lavrion urban area, Attiki, Hellas.

PubMed

Demetriades, Alecos; Li, Xiangdong; Ramsey, Michael H; Thornton, Iain

2010-12-01

In the Lavrion urban area study, Hellas, a five-step sequential extraction method was applied on samples of 'soil' (n = 224), affected by long-term mining and metallurgical activities, and house dust (n = 127), for the purpose of studying the potential bioaccessibility of lead and other metals to humans. In this paper, the Pb concentrations in soil and house dust samples are discussed, together with those in rocks and children's blood. Lead is mainly associated with the carbonate, Fe-Mn oxides and residual fractions in soil and house dust. Considering the very low pH of gastric fluids (1-3), a high amount of metals, present in soil (810-152,000 mg/kg Pb) and house dust (418-18,600 mg/kg Pb), could be potentially bioaccessible. Consequently, children in the neighbourhoods with a large amount of metallurgical processing wastes have high blood-Pb concentrations (5.98-60.49 μg/100 ml; median 17.83 μg/100 ml; n = 235). It is concluded that the Lavrion urban and sub-urban environment is extremely hazardous to human health, and the Hellenic State authorities should urgently tackle this health-related hazard in order to improve the living conditions of local residents.

Activation of human peroxisome-activated receptor-gamma (PPARy) by house dust extracts

EPA Science Inventory

Obesity in children has become an epidemic and recent research suggests a possible contribution from exposure to environmental chemicals. Several chemicals, such as phthalates, brominated flame retardants, and perfluorinated chemicals, are common in house dust on floors where chi...

A new exposure metric for traffic-related air pollution? An analysis of determinants of hopanes in settled indoor house dust.

PubMed

Sbihi, Hind; Brook, Jeffrey R; Allen, Ryan W; Curran, Jason H; Dell, Sharon; Mandhane, Piush; Scott, James A; Sears, Malcolm R; Subbarao, Padmaja; Takaro, Timothy K; Turvey, Stuart E; Wheeler, Amanda J; Brauer, Michael

2013-06-19

Exposure to traffic-related air pollution (TRAP) can adversely impact health but epidemiologic studies are limited in their abilities to assess long-term exposures and incorporate variability in indoor pollutant infiltration. In order to examine settled house dust levels of hopanes, engine lubricating oil byproducts found in vehicle exhaust, as a novel TRAP exposure measure, dust samples were collected from 171 homes in five Canadian cities and analyzed by gas chromatography-mass spectrometry. To evaluate source contributions, the relative abundance of the highest concentration hopane monomer in house dust was compared to that in outdoor air. Geographic variables related to TRAP emissions and outdoor NO2 concentrations from city-specific TRAP land use regression (LUR) models were calculated at each georeferenced residence location and assessed as predictors of variability in dust hopanes. Hopanes relative abundance in house dust and ambient air were significantly correlated (Pearson's r=0.48, p<0.05), suggesting that dust hopanes likely result from traffic emissions. The proportion of variance in dust hopanes concentrations explained by LUR NO2 was less than 10% in Vancouver, Winnipeg and Toronto while the correlations in Edmonton and Windsor explained 20 to 40% of the variance. Modeling with household factors such as air conditioning and shoe removal along with geographic predictors related to TRAP generally increased the proportion of explained variability (10-80%) in measured indoor hopanes dust levels. Hopanes can consistently be detected in house dust and may be a useful tracer of TRAP exposure if determinants of their spatiotemporal variability are well-characterized, and when home-specific factors are considered.

DEVELOPMENT OF ANALYTICAL METHODS FOR SPECIFIC LAWN- APPLIED PESTICIDES IN HOUSE DUST

EPA Science Inventory

Many pesticides have been developed for residential outdoor application, particularly for lawn care. Residues from these applications may be tracked into the home, where they become incorporated with house dust and persist for long periods of time. Consequently, potential human...

DISTRIBUTION OF PESTICIDES AND POLYCYCLIC AROMATIC HYDROCARBONS IN HOUSE DUST AS A FUNCTION OF PARTICLE SIZE

EPA Science Inventory

House dust is a repository for environmental pollutants that may accumulate indoors from both internal and external sources over long periods of time. Dust and tracked-in soil accumulate most efficiently in carpets, and the pollutants associated with it may present an exposure...

Development of a Simultaneous Extraction and Cleanup Method for Pyrethroid Pesticides from Indoor House Dust Samples

EPA Science Inventory

An efficient and reliable analytical method was developed for the sensitive and selective quantification of pyrethroid pesticides (PYRs) in house dust samples. The method is based on selective pressurized liquid extraction (SPLE) of the dust-bound PYRs into dichloromethane (DCM) wi...

Carbamylated monomeric allergoids as a therapeutic option for sublingual immunotherapy of dust mite- and grass pollen-induced allergic rhinoconjunctivitis: a systematic review of published trials with a meta-analysis of treatment using Lais® tablets.

PubMed

Mösges, R; Ritter, B; Kayoko, G; Allekotte, S

2010-10-01

Lais® allergoid tablets contain allergens that are modified by carbamylation. Due to their modified chemical structure, they are suitable for sublingual immunotherapy (SLIT) (13, 16, 17, 24). Based on their small molecule size of 12 to 40 kDa, they can be easily absorbed via the oral mucosa (1). In this review, we studied the efficacy of SLIT with carbamylated monomeric allergoid tablets in the treatment of grass pollen- and dust mite-induced allergic rhinoconjunctivitis on the basis of symptom and medication score improvements. Following a selective internet and databank search, six trials-some placebo-controlled-regarding the treatment of grass pollen- (n = 266) and dust mite-induced (n = 241) allergic rhinoconjunctivitis were used to draw conclusions regarding the clinical efficacy of allergoid tablets. The primary endpoints in these trials were decreases in the need for allergy medications and/or reductions in the occurrence of rhinoconjunctivitis symptoms. Data was recorded from patient diaries regarding their symptoms and medications used and conclusions were then drawn about the effectiveness and tolerabieity of Lais® tablets. The average improvement in symptom score in three trials of grass pollen allergy treatment was 34% in comparison to the placebo group. The treatment of dust mite-induced rhinoconjunctivitis produced an average symptom score improvement of 22% compared to the placebo or control groups. The intake of symptomatic rescue medication during allergoid tablet therapy declined. Treatment of grass pollen allergies and dust mite-induced rhinoconjunctivitis showed an average medication score improvement of 49% and 24%, respectively. Few side effects were documented in the trials and predominantly local effects were observed. Severe systemic side effects did not occur. On the basis of the trial results summarized in this review, we suggest that SLIT using Lais® sublingual tablets is an effective and well-tolerated form of treatment.

Association of pediatric asthma severity with exposure to common household dust allergens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gent, Janneane F., E-mail: janneane.gent@yale.edu; Belanger, Kathleen; Triche, Elizabeth W.

Background: Reducing exposure to household dust inhalant allergens has been proposed as one strategy to reduce asthma. Objective: To examine the dose-response relationships and health impact of five common household dust allergens on disease severity, quantified using both symptom frequency and medication use, in atopic and non-atopic asthmatic children. Methods: Asthmatic children (N=300) aged 4-12 years were followed for 1 year. Household dust samples from two indoor locations were analyzed for allergens including dust mite (Der p 1, Der f 1), cat (Fel d 1), dog (Can f 1), cockroach (Bla g 1). Daily symptoms and medication use were collectedmore » in monthly telephone interviews. Annual disease severity was examined in models including allergens, specific IgE sensitivity and adjusted for age, gender, atopy, ethnicity, and mother's education. Results: Der p 1 house dust mite allergen concentration of 2.0 {mu}g/g or more from the main room and the child's bed was related to increased asthma severity independent of allergic status (respectively, OR 2.93, 95% CI 1.37, 6.30 for 2.0-10.0 {mu}g/g and OR 2.55 95% CI 1.13, 5.73 for {>=}10.0 {mu}g/g). Higher pet allergen levels were associated with greater asthma severity, but only for those sensitized (cat OR 2.41 95% CI 1.19, 4.89; dog OR 2.06 95% CI 1.01, 4.22). Conclusion: Higher levels of Der p 1 and pet allergens were associated with asthma severity, but Der p 1 remained an independent risk factor after accounting for pet allergens and regardless of Der p 1 specific IgE status.« less

A new exposure metric for traffic-related air pollution? An analysis of determinants of hopanes in settled indoor house dust

PubMed Central

2013-01-01

Background Exposure to traffic-related air pollution (TRAP) can adversely impact health but epidemiologic studies are limited in their abilities to assess long-term exposures and incorporate variability in indoor pollutant infiltration. Methods In order to examine settled house dust levels of hopanes, engine lubricating oil byproducts found in vehicle exhaust, as a novel TRAP exposure measure, dust samples were collected from 171 homes in five Canadian cities and analyzed by gas chromatography–mass spectrometry. To evaluate source contributions, the relative abundance of the highest concentration hopane monomer in house dust was compared to that in outdoor air. Geographic variables related to TRAP emissions and outdoor NO2 concentrations from city-specific TRAP land use regression (LUR) models were calculated at each georeferenced residence location and assessed as predictors of variability in dust hopanes. Results Hopanes relative abundance in house dust and ambient air were significantly correlated (Pearson’s r=0.48, p<0.05), suggesting that dust hopanes likely result from traffic emissions. The proportion of variance in dust hopanes concentrations explained by LUR NO2 was less than 10% in Vancouver, Winnipeg and Toronto while the correlations in Edmonton and Windsor explained 20 to 40% of the variance. Modeling with household factors such as air conditioning and shoe removal along with geographic predictors related to TRAP generally increased the proportion of explained variability (10-80%) in measured indoor hopanes dust levels. Conclusions Hopanes can consistently be detected in house dust and may be a useful tracer of TRAP exposure if determinants of their spatiotemporal variability are well-characterized, and when home-specific factors are considered. PMID:23782977

[Gohieria fusca found in dust of air-conditioner filters].

PubMed

Qiang, Chai; Xiao-Dong, Zhan; Wei, Guo; Chao-Pin, Li

2017-09-25

To investigate the pollution status of Gohieria fusca in the air conditioner-filters of different places in Wuhu City. The dust samples were collected from the filters of air-conditioners in dining rooms, shopping malls, hotels and households between June and September, 2013, and G. fusca was detected in the dust samples. There were 430 dust samples collected and 98 were G. fusca positive with the breeding rate of 22.79%. The difference of breeding rates of G. fusca were statistically significant among the different places ( χ 2 =18.294, P < 0.05). Among 510.5 g dust samples in total, 783 G. fusca mites were detected with an average breeding density of 1.53 mite/g. G. fusca breeds in the dust of air-conditioner filters in Wuhu City gravely.

Garden soil and house dust as exposure media for lead uptake in the mining village of Stratoni, Greece.

PubMed

Argyraki, Ariadne

2014-08-01

The relationships between two exposure media, garden soil and house dust, were studied for Pb uptake in Stratoni village in northern Greece, an industrial area of mining and processing of sulphide ore. Lead data for the two media were assessed in terms of total and bioaccessible content, measurement and geochemical variability, and mineralogical composition. It was found that total Pb was enriched in house dust samples by a factor of 2 on average. Total Pb concentration in soil samples had a maximum of 2,040 mg/kg and reached a maximum of 7,000 mg/kg in house dust samples. The estimated variability due to measurement uncertainty was dominated by the sampling process, and the proportion of sampling variance was greater for soil samples, indicating a higher degree of Pb heterogeneity in soil on the given spatial scale of sampling strata. Although the same general spatial trend was observed for both sampling media with decreasing Pb concentration by increasing distance from the ore-processing plant, Pb in dust samples displayed the highest concentrations within a 300-600-m zone from the ore-processing facility. The significant differences which were observed in Pb speciation between the studied media were explained by differences in mineralogical composition of outdoor soil and indoor dust. Lead-enriched Fe and Mn oxides predominated in soil samples while fine galena grains (<10-20 μm diameter) were the major Pb-bearing phase in dust samples. The integrated exposure uptake biokinetic model was used to predict the risk of elevated blood lead levels in children of Stratoni. Model prediction indicated an average probability of 61 % for blood-Pb to exceed 10 μg/dl. The results underline the importance of house dust in risk assessment and highlight the effect of outdoor and indoor conditions on the fate of Pb in the particular environment of Stratoni.

Associations between flame retardant applications in furniture foam, house dust levels, and residents' serum levels.

PubMed

Hammel, Stephanie C; Hoffman, Kate; Lorenzo, Amelia M; Chen, Albert; Phillips, Allison L; Butt, Craig M; Sosa, Julie Ann; Webster, Thomas F; Stapleton, Heather M

2017-10-01

Polyurethane foam (PUF) in upholstered furniture frequently is treated with flame retardant chemicals (FRs) to reduce its flammability and adhere to rigorous flammability standards. For decades, a commercial mixture of polybrominated diphenyl ethers (PBDEs) called PentaBDE was commonly applied to foam to fulfill these regulations; however, concerns over toxicity, bioaccumulation, and persistence led to a global phase-out in the mid-2000s. Although PentaBDE is still detected in older furniture, other FR compounds such as tris(1,3-dichloroisopropyl) phosphate (TDCIPP) and Firemaster® 550 (FM550) have been increasingly used as replacements. While biomonitoring studies suggest exposure is widespread, the primary sources of exposure are not clearly known. Here, we investigated the relationships between specific FR applications in furniture foam and human exposure. Paired samples of furniture foam, house dust and serum samples were collected from a cohort in North Carolina, USA and analyzed for FRs typically used in PUF. In general, the presence of a specific FR in the sofa of a home was associated with an increase in the concentration of that FR in house dust. For example, the presence of PentaBDE in sofas was associated with significantly higher levels of BDE-47, a major component of PentaBDE, in house dust (10 β =6.4, p<0.001). A similar association was observed with a component of FM550, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), with levels that were approximately 3 times higher in house dust when FM550 was identified in the sofa foam (p<0.01). These relationships were modified by dust loading rates in the living room and the ratio of sofa size to room size. Interestingly, levels of TDCIPP and tris(1-chloro-2-isopropyl) phosphate (TCIPP) were also higher in dust with detections in sofa foam; however, these associations were not statistically significant and may suggest there are other prominent sources of these compounds in the home. In addition, the

On the problem of nonsense correlations in allergological tests after routine extraction.

PubMed

Rijckaert, G

1981-01-01

The influence of extraction procedures and culturing methods of material used for the preparation of allergenic extracts on correlation patterns found in allergological testing (skin test and RAST) was investigated. In our laboratory a short extraction procedure performed at O degrees C was used for Aspergillus repens. A. penicilloides, Wallemia sebi, their rearing media and non-inoculated medium. For the commercially available extracts from house dust, house-dust mite, pollen of Dactylus glomerata and A. penicilloides a longer procedure (several days) performed at room temperature was used. Statistical analysis showed a separation of all test results into two clusters, each cluster being composed of correlations between extracts from only one the manufacturers did not show any correlation. The correlations found between the short time incubated extracts of the xerophilic fungi and their rearing media could be explained by genetical and biochemical relationships between these fungi depending on ecological conditions. However, while the correlation found between house dust and house-dust mite is understandable, correlations found between long time incubated extracts from house-dust mite and D. glomerata or A. penicilloides may be nonsense correlations, that do not adequately describe the in vivo situation. The similarity of these extracts is presumably artificially created during extraction.

Fusarium semitectum, a potential mycopathogen against thrips and mites in chilli, Capsicum annuum.

PubMed

Mikunthan, G; Manjunatha, M

2006-01-01

In India, chilli (Capsicum annuum L.) suffers with a characteristic leaf curl symptoms due to the attack of mite, Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae) and thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) or both. Experiments were conducted in the fields of College of Agriculture, Shimoga, India during kharif (September 2003 to January 2004) and summer (March-June) 2004. After proving its pathogenicity, the potential of the mycopathogen, Fusarium semitectum was evaluated under field conditions using the popular chilli variety "Byadagi". Different combinations of Fusarium semitectum formulations with monocrotophos (0.025% and 0.05%) were tested. Oil-emulsion and dust-water formulations (DWF) at 1x 10(8) spore/ml, DWF with monocrotophos and 5% Neem Seed Kernal Extract (NSKE) were evaluated. Population of S. dorsalis, P. latus, predatory mite Amblyseius ovalis and damage index were estimated. Populations of thrips, mite and the predatory mite were estimated at 15 days interval after 30 days of transplanting. Damage index was assessed using a visual rating method. Plant height, fruit length and dry chilli yield of each treatment were also taken. Among the treatments, oil-emulsion formulation and dust water formulation of F. semitectum in combination with monocrotophos (0.05%) reduced the population of thrips significantly over other treatments. Dust water formulation was achieved a significant decline of thrips population in chilli plants after 60 days of transplanting. This reduction of thrips population could be achieved due to the effect of second spraying, which was given at 50 days after transplanting. Chilli plant height and fruit length did not vary significantly among the treatment in both seasons. The highest dry chilli yield of 512 and 1058 kg/ha was recorded in dust water formulation in combination with monocrotophos (0.05%) followed by oil formulation (432 kg/ha and 763 kg/ha) in Kharif and summer seasons, respectively

[Analysis of allergens characteristic in 1172 patients with allergic rhinitis in Changzhou area].

PubMed

Shi, Mei; Yao, Lina; Yang, Xiaojun; Chen, Jian; Zhang, Lirong; Sun, Jing; Xu, Xiaopeng

2016-01-01

To determine the distribution of allergens in patients with allergic rhinitis during from 2008 to 2015 in Changzhou area. Allergy Screen method was used to detect the specifical-allergen IgE levels of 1172 patients with allergic rhinitis. Among the patients, the distribution of all allergens was analyzed. The positive rate was compared with age, gender, season and so on. The most common allergens in allergic rhinitis patients in Changzhou were dust mite, fungus, house dust, milk, dander of dog, weed mixture, farina and dander of cat. The more higher positive rates of dust mite, fungus, house dust, milk, dander of dog, dander of cat, eggs were found in teenager group than adult group (P < 0.05). There were more higer positive rates of weed mixture, farina, cashew, cockroaches and crab in teenager group than adult group (P < 0.05). There was no significant difference of positive rate between female group and male group. There was significant difference of variation with seasons. Dust mite, fungus and house dust were the most common allergens among patiens with allergic rhinitis in Changzhou area. The positive rates of allergens varied with ages and seasons.

Nurse Case Management and Housing Interventions Reduce Allergen Exposures: The Milwaukee Randomized Controlled Trial

PubMed Central

Breysse, Jill; Wendt, Jean; Dixon, Sherry; Murphy, Amy; Wilson, Jonathan; Meurer, John; Cohn, Jennifer; Jacobs, David E.

2011-01-01

Objective We examined the impact of a combination of home environmental interventions and nurse case management services on total settled dust loadings and on allergen concentrations in the homes of asthmatic children. Methods Using a randomized longitudinal controlled trial study design, we randomly assigned homes of asthmatic children in Milwaukee to either a control (n=64) or an intervention (n=57) group. Control group homes received a visual assessment, education, bed/pillow dust mite encasings, and treatment of lead-based paint hazards. The intervention group received these same services plus nurse case management that included tailored, individual asthma action plans, provision of minor home repairs, home cleaning using special vacuuming and wet washing, and integrated pest management. Dust vacuum samples were collected from measured surface areas of floors in the TV room, kitchen, and child's bedroom at baseline and at three-, six-, and 12-month follow-up visits. Dust loading (mass per surface area) is a means of measuring total dust and the total amount of allergen present. Results For the intervention group, geometric mean dust loadings declined significantly from baseline (39 milligrams per square foot [mg/ft2]) to post-intervention (11 mg/ft2) (p<0.001). Baseline dust loading, treatment group, visit, and season were significant predictors of follow-up dust loadings. Mean post-intervention dust loadings were 72% higher in the control group. The total amount of allergen in settled house dust declined significantly following the intervention because total dust loading declined; the concentration of allergens in settled dust did not change significantly. Conclusion The combination of nurse case management and home environmental interventions promotes collaboration between health and housing professionals and is effective in reducing exposures to allergens in settled dust. PMID:21563716

Overview on relative importance of house dust ingestion in human exposure to polybrominated diphenyl ethers (PBDEs): International comparison and Korea as a case.

PubMed

Kim, Seung-Kyu; Kim, Kyoung-Soo; Sang, Hee Hong

2016-11-15

Human exposure studies to polybrominated diphenyl ethers (PBDEs) have reached different results about the relative importance of diet intake and house dust ingestion. In the present study, concentrations of PBDEs in Korean house dust (n=15) from geographically different cities were measured, which were in agreement with a previous result, and compared with those for 22 countries of five continents collected from the most recent scientific literature. Compared with other exposure pathways, diet intake was the most important contributor to total PBDEs exposure of Korean adults (i.e., 71% of overall intake). On global comparison, total PBDE levels in house dust differed by two to three orders of magnitude among the countries investigated, with a significant relationship with gross domestic product (GDP). Whereas, dietary daily intakes exhibited a narrow difference within one order of magnitude worldwide and no relationship with GDP. Consequently, the relative importance of major two pathways depended on the contamination extent of PBDEs in house dust, which may be associated with the amount of PBDE products in use. In most countries except for UK and USA, the contribution of house dust ingestion was less important than diet intake in the current and are expected to much more mitigate in the future. However, how fast the effect of regulation will be reflected to house dust and human exposure is necessary to be monitored steadily. Copyright © 2016 Elsevier B.V. All rights reserved.

Mutagenic Azo Dyes, Rather Than Flame Retardants, Are the Predominant Brominated Compounds in House Dust.

PubMed

Peng, Hui; Saunders, David M V; Sun, Jianxian; Jones, Paul D; Wong, Chris K C; Liu, Hongling; Giesy, John P

2016-12-06

Characterization of toxicological profiles by use of traditional targeted strategies might underestimate the risk of environmental mixtures. Unbiased identification of prioritized compounds provides a promising strategy for meeting regulatory needs. In this study, untargeted screening of brominated compounds in house dust was conducted using a data-independent precursor isolation and characteristic fragment (DIPIC-Frag) approach, which used data-independent acquisition (DIA) and a chemometric strategy to detect peaks and align precursor ions. A total of 1008 brominated compound peaks were identified in 23 house dust samples. Precursor ions and formulas were identified for 738 (73%) of the brominated compounds. A correlation matrix was used to cluster brominated compounds; three large groups were found for the 140 high-abundance brominated compounds, and only 24 (17%) of these compounds were previously known flame retardants. The predominant class of unknown brominated compounds was predicted to consist of nitrogen-containing compounds. Following further validation by authentic standards, these compounds (56%) were determined to be novel brominated azo dyes. The mutagenicity of one major component was investigated, and mutagenicity was observed at environmentally relevant concentrations. Results of this study demonstrated the existence of numerous unknown brominated compounds in house dust, with mutagenic azo dyes unexpectedly being identified as the predominant compounds.

Anti-inflammatory potential of a heat-killed Lactobacillus strain isolated from Kimchi on house dust mite-induced atopic dermatitis in NC/Nga mice.

PubMed

Choi, C-Y; Kim, Y-H; Oh, S; Lee, H J; Kim, J H; Park, S H; Kim, H J; Lee, S J; Chun, T

2017-08-01

Atopic dermatitis (AD) is an allergic skin disease driven by the Th2-prone immune response. Therefore, a fundamental approach to restoring the Th1/Th2 balance is needed to treat AD. Eighteen different Lactobacillus strains isolated from Kimchi were screened to identify those that stimulated immune cells to secret Th1-type or Th2-type cytokines. Lactobacillus brevis NS1401 induced the greatest IFN-γ and IL-12 secretion and the least IL-4 production among the tested Lactobacillus strains. Furthermore, oral administration of heat-killed NS1401 ameliorated the symptoms of dust mite-induced AD in NC/Nga mice by decreasing the serum IgE level and reducing the number of mast cells and eosinophils in lesions. Also, the size and number of cells in the draining lymph nodes of NS1401-administered mice were significantly reduced. In agreement with these results, secretion of a Th1-type cytokine (IFN-γ) and allergen-specific IgG2a were increased, whereas secretion of Th2-type cytokines (IL-4, IL-5, and IL-10) and allergen-specific IgG1 were decreased upon administration of NS1401 in mice. Lactobacillus brevis NS1401 alleviates the symptoms of AD by restoring the Th1/Th2 balance through enhancing Th1-prone immunity. The immunomodulatory function of L. brevis NS1401 may provide effective new therapeutics against AD. © 2017 The Society for Applied Microbiology.

House Dust Endotoxin Levels Are Associated with Adult Asthma in a U.S. Farming Population

PubMed Central

Carnes, Megan Ulmer; Hoppin, Jane A.; Metwali, Nervana; Wyss, Annah B.; Hankinson, John L.; O’Connell, Elizabeth Long; Richards, Marie; Long, Stuart; Freeman, Laura E. Beane; Sandler, Dale P.; Henneberger, Paul K.; Barker-Cummings, Christie; Umbach, David M.; Thorne, Peter S.

2017-01-01

Rationale: Endotoxin initiates a proinflammatory response from the innate immune system. Studies in children suggest that endotoxin exposure from house dust may be an important risk factor for asthma, but few studies have been conducted in adult populations. Objectives: To investigate the association of house dust endotoxin levels with asthma and related phenotypes (wheeze, atopy, and pulmonary function) in a large U.S. farming population. Methods: Dust was collected from the bedrooms (n = 2,485) of participants enrolled in a case–control study of current asthma (927 cases) nested within the Agricultural Health Study. Dust endotoxin was measured by Limulus amebocyte lysate assay. Outcomes were measured by questionnaire, spirometry, and blood draw. We evaluated associations using linear and logistic regression. Measurements and Main Results: Endotoxin was significantly associated with current asthma (odds ratio [OR], 1.30; 95% confidence interval [CI], 1.14–1.47), and this relationship was modified by early-life farm exposure (born on a farm: OR, 1.18; 95% CI, 1.02–1.37; not born on a farm: OR, 1.67; 95% CI, 1.26–2.20; Interaction P = 0.05). Significant positive associations were seen with both atopic and nonatopic asthma. Endotoxin was not related to either atopy or wheeze. Higher endotoxin was related to lower FEV1/FVC in asthma cases only (Interaction P = 0.01). For asthma, there was suggestive evidence of a gene-by-environment interaction for the CD14 variant rs2569190 (Interaction P = 0.16) but not for the TLR4 variants rs4986790 and rs4986791. Conclusions: House dust endotoxin was associated with current atopic and nonatopic asthma in a U.S. farming population. The degree of the association with asthma depended on early-life farm exposures. Furthermore, endotoxin was associated with lower pulmonary function in patients with asthma. PMID:27977294

House Dust Endotoxin Levels Are Associated with Adult Asthma in a U.S. Farming Population.

PubMed

Carnes, Megan Ulmer; Hoppin, Jane A; Metwali, Nervana; Wyss, Annah B; Hankinson, John L; O'Connell, Elizabeth Long; Richards, Marie; Long, Stuart; Freeman, Laura E Beane; Sandler, Dale P; Henneberger, Paul K; Barker-Cummings, Christie; Umbach, David M; Thorne, Peter S; London, Stephanie J

2017-03-01

Endotoxin initiates a proinflammatory response from the innate immune system. Studies in children suggest that endotoxin exposure from house dust may be an important risk factor for asthma, but few studies have been conducted in adult populations. To investigate the association of house dust endotoxin levels with asthma and related phenotypes (wheeze, atopy, and pulmonary function) in a large U.S. farming population. Dust was collected from the bedrooms (n = 2,485) of participants enrolled in a case-control study of current asthma (927 cases) nested within the Agricultural Health Study. Dust endotoxin was measured by Limulus amebocyte lysate assay. Outcomes were measured by questionnaire, spirometry, and blood draw. We evaluated associations using linear and logistic regression. Endotoxin was significantly associated with current asthma (odds ratio [OR], 1.30; 95% confidence interval [CI], 1.14-1.47), and this relationship was modified by early-life farm exposure (born on a farm: OR, 1.18; 95% CI, 1.02-1.37; not born on a farm: OR, 1.67; 95% CI, 1.26-2.20; Interaction P = 0.05). Significant positive associations were seen with both atopic and nonatopic asthma. Endotoxin was not related to either atopy or wheeze. Higher endotoxin was related to lower FEV 1 /FVC in asthma cases only (Interaction P = 0.01). For asthma, there was suggestive evidence of a gene-by-environment interaction for the CD14 variant rs2569190 (Interaction P = 0.16) but not for the TLR4 variants rs4986790 and rs4986791. House dust endotoxin was associated with current atopic and nonatopic asthma in a U.S. farming population. The degree of the association with asthma depended on early-life farm exposures. Furthermore, endotoxin was associated with lower pulmonary function in patients with asthma.

Th2 polarization by Der p 1--pulsed monocyte-derived dendritic cells is due to the allergic status of the donors.

PubMed

Hammad, H; Charbonnier, A S; Duez, C; Jacquet, A; Stewart, G A; Tonnel, A B; Pestel, J

2001-08-15

The polarization of the immune response toward a Th2 or a Th1 profile can be mediated by dendritic cells (DCs) following antigen presentation and interaction with T cells. Costimulatory molecules such as CD80 and CD86 expressed by DCs, the polarizing cytokine environment during DC--T-cell interaction, and also the nature of the antigen are critical in the orientation of the immune response. In this study, the effect of the cysteine protease Der p 1, one of the major allergens of the house dust mite Dermatophagoides pteronyssinus, on these different parameters was evaluated comparatively on monocyte-derived DCs obtained from healthy donors, from pollen-sensitive patients, or from patients sensitive to Dermatophagoides pteronyssinus. Results showed that Der p 1 induced an increase in CD86 expression only on DCs from house dust mite--sensitive patients. This was also associated with a higher capacity to induce T-cell proliferation, a rapid increase in the production of proinflammatory cytokines, tumor necrosis factor--alpha and interleukin (IL)-1 beta, and the type 2 cytokine IL-10. No changes in the release of IL-12 p70 were induced by Der p 1. Finally, purified T cells from house dust mite-sensitive patients stimulated by autologous Der p 1--pulsed DCs preferentially produced IL-4 rather than interferon-gamma. These effects were abolished in the presence of the inactive precursor of Der p 1 (ProDer p 1). Taken together, these data suggest that DCs from house dust mite--sensitive patients, in contrast to DCs from healthy donors and from pollen-sensitive patients, exposed to Der p 1 play a pivotal role in the enhancement of the Th2 response associated with the allergic reaction developed in response to house dust mite exposure. (Blood. 2001;98:1135-1141)

Optimal cutoff values of allergen-specific immunoglobulin E to house dust mites and animal dander based on skin-prick test results: Analysis in 16,209 patients with allergic rhinitis.

PubMed

2017-10-25

The most common tests for allergen sensitization in patients with allergic rhinitis are the skin-prick test(SPT) and an in vitro test to detect serum specific immunoglobulin E (sIgE). However, in vitro allergen test results were interpreted dichotomically as positive or negative at a threshold of 0.35kU/L of sIgE, regardless of the patient characteristics or antigen types. The purpose of this study was to determine the cutoff value for sIgE in house-dust mites and animal dander, and to analyze differences in cutoff value according to age and gender. A total of 16,209 patients with more than one allergic rhinitis symptom who underwent both SPT and serum sIgE testing were retrospectively evaluated between March 2008 and May 2012. There were 9374 male (57.8%) and 6835 female (42.2%) patients. The mean age was 31.8 years (range, 2-89 years). The criterion standard for allergen sensitization was defined as a wheal of > 3 mm or an allergen-to-histamine ratio of greater than or equal to 1 in SPT results. The Youden index was used to calculate the cutoff value of sIgE. Cutoff values of sIgE for Dermatophagoides pteronyssinus, Dermatophagoides farinae, cat, and dog were 0.69, 1.16, 0.13, and 0.45 kU/L, respectively. The cutoff value of sIgE changed according to age for D. pteronyssinus and D. farinae but not for cat and dog allergens. When categorizingaccording to age group, the cutoff values of sIgE for D. pteronyssinus and D. farinae had a tendency to decrease with age. There was no significant difference in cutoff value according to gender. The cutoff value for sIgE differed for each antigen and changed with age. Physicians should select the proper cutoff value for sIgE for appropriate criteria according to antigen and patient age rather than using a uniform cutoff value.

Optimal cutoff values of allergen-specific immunoglobulin E to house dust mites and animal dander based on skin-prick test results: Analysis in 16,209 patients with allergic rhinitis.

PubMed

Hong, Sang Duk; Ryu, Gwanghui; Seo, Min Young; Jeong, Jong In; Kim, Hyo Yeol; Chung, Seung-Kyu; Dhong, Hun-Jong

2018-01-25

The most common tests for allergen sensitization in patients with allergic rhinitis are the skin-prick test (SPT) and an in vitro test to detect serum specific immunoglobulin E (sIgE). However, in vitro allergen test results were interpreted dichotomically as positive or negative at a threshold of 0.35 kU/L of sIgE, regardless of the patient characteristics or antigen types. The purpose of this study was to determine the cutoff value for sIgE in house-dust mites and animal dander, and to analyze differences in cutoff value according to age and gender. A total of 16,209 patients with more than one allergic rhinitis symptom who underwent both SPT and serum sIgE testing were retrospectively evaluated between March 2008 and May 2012. There were 9374 male (57.8%) and 6835 female (42.2%) patients. The mean age was 31.8 years (range, 2-89 years). The criterion standard for allergen sensitization was defined as a wheal of >3 mm or an allergen-to-histamine ratio of ≥1 in SPT results. The Youden index was used to calculate the cutoff value of sIgE. Cutoff values of sIgE for Dermatophagoides pteronyssinus, Dermatophagoides farinae, cat, and dog were 0.69, 1.16, 0.13, and 0.45 kU/L, respectively. The cutoff value of sIgE changed according to age for D. pteronyssinus and D. farinae but not for cat and dog allergens. When categorizing according to age group, the cutoff values of sIgE for D. pteronyssinus and D. farinae had a tendency to decrease with age. There was no significant difference in cutoff value according to gender. The cutoff value for sIgE differed for each antigen and changed with age. Physicians should select the proper cutoff value for sIgE for appropriate criteria according to antigen and patient age rather than using a uniform cutoff value.

Utilizing Pyrosequencing and Quantitative pCR to Characterize Fungal Populations among House Dust Samples

EPA Science Inventory

Molecular techniques are an alternative to culturing and counting methods in quantifying indoor fungal contamination. Pyrosequencing offers the possibility of identifying unexpected indoor fungi. In this study, 50 house dust samples were collected from homes in the Yakima Valley,...

Human Exposure Assessment: Development of methods to assess the bioaccessibility of organic contaminants sorbed to soils and house dusts

EPA Science Inventory

Research task- Are physicochemical properties of soil and house dust predictive of the bioaccessibility of sorbed organic compoundsGoalIdentify dust and soil characteristics that influence the bioaccessibility of organic compounds and provide chemical specific data on the fractio...

The Potential for a Blood Test for Scabies.

PubMed

Arlian, Larry G; Feldmeier, Hermann; Morgan, Marjorie S

2015-01-01

Scabies afflicts millions of people worldwide, but it is very difficult to diagnose by the usual skin scrape test, and a presumptive diagnosis is often made based on clinical signs such as rash and intense itch. A sensitive and specific blood test to detect scabies would allow a physician to quickly make a correct diagnosis. Our objective was to profile the mite-specific antibodies present in the sera of patients with ordinary scabies. Sera of 91 patients were screened for Ig, IgD, IgE, IgG and IgM antibodies to S. scabiei, as well as to the house dust mites Dermatophagoides farinae, D. pteronyssinus and Euroglyphus maynei. 45%, 27% and 2.2% of the patients had measurable amounts of mixed Ig, IgG and IgE that recognized scabies mite antigens. However, 73.6% of the scabies patients had serum IgM that recognized scabies proteins, and all except two of them also had IgM that recognized all of the three species of dust mites. No patient had serum antibody exclusively reactive to scabies mite antigens. Co-sensitization or cross-reactivity between antigens from scabies and house dust mites confounds developing a blood test for scabies.

Lead speciation in indoor dust: a case study to assess old paint contribution in a Canadian urban house

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beauchemin, Suzanne; MacLean, Lachlan C.W.; Rasmussen, Pat E.

Residents in older homes may experience increased lead (Pb) exposures due to release of lead from interior paints manufactured in past decades, especially pre-1960s. The objective of the study was to determine the speciation of Pb in settled dust from an urban home built during WWII. X-ray absorption near-edge structure (XANES) and micro-X-ray diffraction (XRD) analyses were performed on samples of paint (380-2,920 mg Pb kg{sup -1}) and dust (200-1,000 mg Pb kg{sup -1}) collected prior to renovation. All dust samples exhibited a Pb XANES signature similar to that of Pb found in paint. Bulk XANES and micro-XRD identified Pbmore » species commonly found as white paint pigments (Pb oxide, Pb sulfate, and Pb carbonate) as well as rutile, a titanium-based pigment, in the <150 {micro}m house dust samples. In the dust fraction <36 {micro}m, half of the Pb was associated with the Fe-oxyhydroxides, suggesting additional contribution of outdoor sources to Pb in the finer dust. These results confirm that old paints still contribute to Pb in the settled dust for this 65-year-old home. The Pb speciation also provided a clearer understanding of the Pb bioaccessibility: Pb carbonate > Pb oxide > Pb sulfate. This study underscores the importance of taking precautions to minimize exposures to Pb in house dust, especially in homes where old paint is exposed due to renovations or deterioration of painted surfaces.« less

Lead Speciation in Indoor Dust: A Case Study to Assess Old Paint Contribution in a Canadian Urban House

DOE Office of Scientific and Technical Information (OSTI.GOV)

S Beauchemin; L MacLean; P Rasmussen

Residents in older homes may experience increased lead (Pb) exposures due to release of lead from interior paints manufactured in past decades, especially pre-1960s. The objective of the study was to determine the speciation of Pb in settled dust from an urban home built during WWII. X-ray absorption near-edge structure (XANES) and micro-X-ray diffraction (XRD) analyses were performed on samples of paint (380-2,920 mg Pb kg{sup -1}) and dust (200-1,000 mg Pb kg{sup -1}) collected prior to renovation. All dust samples exhibited a Pb XANES signature similar to that of Pb found in paint. Bulk XANES and micro-XRD identified Pbmore » species commonly found as white paint pigments (Pb oxide, Pb sulfate, and Pb carbonate) as well as rutile, a titanium-based pigment, in the <150 m house dust samples. In the dust fraction <36 {mu}m, half of the Pb was associated with the Fe-oxyhydroxides, suggesting additional contribution of outdoor sources to Pb in the finer dust. These results confirm that old paints still contribute to Pb in the settled dust for this 65-year-old home. The Pb speciation also provided a clearer understanding of the Pb bioaccessibility: Pb carbonate > Pb oxide > Pb sulfate. This study underscores the importance of taking precautions to minimize exposures to Pb in house dust, especially in homes where old paint is exposed due to renovations or deterioration of painted surfaces.« less

Concentrations and sources of cadmium, copper, lead and zinc in house dust in Christchurch, New Zealand.

PubMed

Kim, N; Fergusson, J

1993-09-30

The amounts (microgram m-2) and concentrations (microgram g-1) of cadmium, copper, lead and zinc have been measured in house dust in Christchurch, New Zealand. For 120 houses surveyed the geometric mean concentrations of the four metals are 4.24 micrograms g-1, 165 micrograms g-1, 573 micrograms g-1 and 10,400 micrograms g-1, respectively. In addition eleven variables, such as house age, carpet wear and traffic density, were recorded for each property and the results analysed with respect to their effects on the amounts and concentrations of the four elements. The amounts of all the metals were highly correlated with the overall dustiness of the houses, which was found to be predominantly determined by the degree of carpet wear. No one dominant source of cadmium was identified, although several minor sources including carpet wear, galvanized iron roofs and red/orange/yellow coloured carpets were implicated. Petrol lead and lead-based paints were identified as significant sources of lead in house dust. Rubber carpet underlays or backings were identified as a significant source of zinc, with some contribution from galvanized iron roofs. Road traffic and probably the existence of a fire place appear to contribute to the copper levels.

Foliar nectar enhances plant-mite mutualisms: the effect of leaf sugar on the control of powdery mildew by domatia-inhabiting mites.

PubMed

Weber, Marjorie G; Porturas, Laura D; Taylor, Scott A

2016-09-01

Mite domatia are small structures on the underside of plant leaves that provide homes for predacious or fungivorous mites. In turn, mites inhabiting domatia defend the plant by consuming leaf herbivores and pathogens, which can result in a domatia-mediated, plant-mite defence mutualism. Several recent studies have suggested that plants receive enhanced benefits when they provide a foliar food source, such as sugars secreted from extrafloral nectaries, to mite mutualists alongside mite domatia. However, the effect of foliar sugar on reducing leaf pathogen load via domatia-inhabiting mites has not been directly investigated. To fill this gap, the links between foliar sugar addition, domatia-inhabiting mite abundance, and pathogen load were experimentally evaluated in wild grape. Furthermore, because the proposed combined benefits of providing food and housing have been hypothesized to select for the evolutionary correlation of extrafloral nectaries and domatia across plant lineages, a literature survey aimed at determining the overlap of mite domatia and extrafloral nectaries across plant groups was also conducted. It was found that leaves with artificial addition of foliar sugar had 58-80 % more mites than leaves without foliar sugar addition, and that higher mite abundances translated to reduced powdery mildew (Erysiphe necator) loads on leaves. It was found that mite domatia and extrafloral nectaries occur non-randomly in the same clades across Eudicots. Genera with both traits are reported to highlight candidate lineages for future studies. Together, the results demonstrate that foliar sugar can indeed enhance the efficacy of domatia-mediated plant-mite mutualisms, and suggest that this synergism has the potential to influence the co-distribution of foliar nectar and mite domatia across plants. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Foliar nectar enhances plant–mite mutualisms: the effect of leaf sugar on the control of powdery mildew by domatia-inhabiting mites

PubMed Central

Weber, Marjorie G.; Porturas, Laura D.; Taylor, Scott A.

2016-01-01

Background and Aims Mite domatia are small structures on the underside of plant leaves that provide homes for predacious or fungivorous mites. In turn, mites inhabiting domatia defend the plant by consuming leaf herbivores and pathogens, which can result in a domatia-mediated, plant–mite defence mutualism. Several recent studies have suggested that plants receive enhanced benefits when they provide a foliar food source, such as sugars secreted from extrafloral nectaries, to mite mutualists alongside mite domatia. However, the effect of foliar sugar on reducing leaf pathogen load via domatia-inhabiting mites has not been directly investigated. Methods To fill this gap, the links between foliar sugar addition, domatia-inhabiting mite abundance, and pathogen load were experimentally evaluated in wild grape. Furthermore, because the proposed combined benefits of providing food and housing have been hypothesized to select for the evolutionary correlation of extrafloral nectaries and domatia across plant lineages, a literature survey aimed at determining the overlap of mite domatia and extrafloral nectaries across plant groups was also conducted. Key Results It was found that leaves with artificial addition of foliar sugar had 58–80 % more mites than leaves without foliar sugar addition, and that higher mite abundances translated to reduced powdery mildew (Erysiphe necator) loads on leaves. It was found that mite domatia and extrafloral nectaries occur non-randomly in the same clades across Eudicots. Genera with both traits are reported to highlight candidate lineages for future studies. Conclusions Together, the results demonstrate that foliar sugar can indeed enhance the efficacy of domatia-mediated plant–mite mutualisms, and suggest that this synergism has the potential to influence the co-distribution of foliar nectar and mite domatia across plants. PMID:27343230

Measurement of nicotine in household dust

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Sungroul; Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205; Aung, Ther

An analytical method of measuring nicotine in house dust was optimized and associations among three secondhand smoking exposure markers were evaluated, i.e., nicotine concentrations of both house dust and indoor air, and the self-reported number of cigarettes smoked daily in a household. We obtained seven house dust samples from self-reported nonsmoking homes and 30 samples from smoking homes along with the information on indoor air nicotine concentrations and the number of cigarettes smoked daily from an asthma cohort study conducted by the Johns Hopkins Center for Childhood Asthma in the Urban Environment. House dust nicotine was analyzed by isotope dilutionmore » gas chromatography-mass spectrometry (GC/MS). Using our optimized method, the median concentration of nicotine in the dust of self-reported nonsmoking homes was 11.7 ng/mg while that of smoking homes was 43.4 ng/mg. We found a substantially positive association (r=0.67, P<0.0001) between house dust nicotine concentrations and the numbers of cigarettes smoked daily. Optimized analytical methods showed a feasibility to detect nicotine in house dust. Our results indicated that the measurement of nicotine in house dust can be used potentially as a marker of longer term SHS exposure.« less

Endotoxin and dust at respirable and nonrespirable particle sizes are not consistent between cage- and floor-housed poultry operations.

PubMed

Kirychuk, Shelley P; Reynolds, Stephen J; Koehncke, Niels K; Lawson, Joshua; Willson, Philip; Senthilselvan, Ambikaipakan; Marciniuk, Darcy; Classen, Henry L; Crowe, Trever; Just, Natasha; Schneberger, David; Dosman, James A

2010-10-01

Individuals engaged in work in intensive animal houses experience some of the highest rates of occupationally related respiratory symptoms. Organic dust and in particular endotoxin has been most closely associated with respiratory symptoms and lung function changes in workers. It has previously been shown that for intensive poultry operations, type of poultry housing [cage-housed (CH) versus floor-housed (FH)] can influence the levels of environmental contaminants. The goal of the study was to determine the differences in endotoxin and dust levels at different size fractions between CH and FH poultry operations. Fifteen CH and 15 FH poultry operations were sampled for stationary measurements (area) of dust and associated endotoxin. Fractioned samples were collected utilizing Marple cascade impactors. Gravimetric and endotoxin analysis were conducted on each of the filters. When assessed by individual Marple stage, there was significantly greater airborne endotoxin concentration (endotoxin units per cubic meter) in the size fraction >9.8 μm for the FH operations whereas at the size fraction 1.6-3.5 μm, the CH operations had significantly greater airborne endotoxin concentration than the FH operations. Endotoxin concentration in the dust mass (endotoxin units per milligram) was significantly greater in the CH operations as compared to the FH operations for all size fractions >1.6 μm. As such, endotoxin in the respirable fraction accounted for 24% of the total endotoxin in the CH operations whereas it accounted for only 11% in the FH operations. There was significantly more dust in all size fractions in the FH operations as compared to the CH poultry operations. There is more endotoxin in the presence of significantly lower dust levels in the respirable particle size fractions in CH poultry operations as compared to the FH poultry operations. This difference in respirable endotoxin may be important in relation to the differential respiratory response experienced by

Haematophagus Mites in Poultry Farms of Iran

PubMed Central

Rahbari, S; Nabian, S; Ronaghi, H

2009-01-01

Background: Blood sucking mites are important avian ectoparasites which being found on bird species worldwide. Their presence are problematic for the producers either through potential direct effects on weight gain, egg production, sperm production in roosters or as nuisance pests on worker handle hens and eggs. The aim of this study was pointing out of the status of haematophagus mites. Methods: Eight caged layer and four breeder flocks were visited, monitoring for the presence of chicken mites performed by removing and examining debris from poultry house, infested nesting material collected into zip lock plastic bags and at least 20 birds were also randomly selected to examine the presence of chicken mites. Mites obtained from each population were mounted in Hoyer’s medium on microscope slides and identified. All eight caged layer and four breeder flocks were inspected, which were infested with chicken blood feeding mites. Results: Massive infestations of Dermanyssus gallinae were common with huge numbers of parasites on birds, cages and the conveyor belts for egg. Only one farm from Mazandaran Province was infested to Ornithonyssus bursa. Conclusion: Dermanyssus gallinae was the most prevalent blood feeder mite in the breeder and caged layer flocks in Iran, while O. bursa was reported as a first record, which found only in a breeder flock in Mazanderan Province. It seems that its presence is limited into the area which affected by both warm and humid environmental conditions. PMID:22808378

Associations between bacterial communities of house dust and infant gut

DOE Office of Scientific and Technical Information (OSTI.GOV)

Konya, T.; Koster, B.; Maughan, H.

The human gut is host to a diverse and abundant community of bacteria that influence health and disease susceptibility. This community develops in infancy, and its composition is strongly influenced by environmental factors, notably perinatal anthropogenic exposures such as delivery mode (Cesarean vs. vaginal) and feeding method (breast vs. formula); however, the built environment as a possible source of exposure has not been considered. Here we report on a preliminary investigation of the associations between bacteria in house dust and the nascent fecal microbiota from 20 subjects from the Canadian Healthy Infant Longitudinal Development (CHILD) Study using high-throughput sequence analysismore » of portions of the 16S rRNA gene. Despite significant differences between the dust and fecal microbiota revealed by Nonmetric Multidimensional Scaling (NMDS) analysis, permutation analysis confirmed that 14 bacterial OTUs representing the classes Actinobacteria (3), Bacilli (3), Clostridia (6) and Gammaproteobacteria (2) co-occurred at a significantly higher frequency in matched dust–stool pairs than in randomly permuted pairs, indicating an association between these dust and stool communities. These associations could indicate a role for the indoor environment in shaping the nascent gut microbiota, but future studies will be needed to confirm that our findings do not solely reflect a reverse pathway. Although pet ownership was strongly associated with the presence of certain genera in the dust for dogs (Agrococcus, Carnobacterium, Exiguobacterium, Herbaspirillum, Leifsonia and Neisseria) and cats (Escherichia), no clear patterns were observed in the NMDS-resolved stool community profiles as a function of pet ownership.« less

[Sampling of allergens in dust deposited in the workplace].

PubMed

Perfetti, L; Galdi, E; Pozzi, V; Moscato, G

2001-01-01

Some workplaces share with domestic dwellings many characteristics favouring house dust mite growth. Moreover it has recently been shown that pets owners can bring allergens to public places with their clothes. So it is possible that significant exposure to indoor allergens can occur outside homes, at the workplace. The recent availability of immunoassays with monoclonal antibodies for indoor allergens has enabled many investigators to quantify exposure to such allergens in epidemiological studies. Analysis of allergens in settled dust is a simple method of quantification exposure to indoor allergens. The concentrations of indoor allergens in public places have already been investigated and high levels of indoor allergens have been reported. A study performed by our group in offices (banks and media) in different regions of Italy has also shown significant levels of indoor allergens. Thus, evaluating exposure to indoor allergens at the workplace is critical to evaluate risk factors for sensitization and elicitation of symptoms in sensitized subjects and such data help in addressing correctly the problem of reducing exposure levels.

[The use and successfulness of minihygrometers for studying the ecology of house dust mites in Central Asia].

PubMed

Nazrullaeva, M F; Alekseev, A N

1991-01-01

The efficacy of minihygrometers in the study of bed microclimate (a shelter of dust ticks) has been assessed. Maximum difference between minihygrometer and August's psychrometer parameters reaches 0.5%. In all shelters of ticks humidity at night was higher than in the premises, which demonstrates the efficacy of the method used.

Acaroid mite allergens from the filters of air-conditioning system in China.

PubMed

Li, Chao-Pin; Guo, Wei; Zhan, Xiao-Dong; Zhao, Bei-Bei; Diao, Ji-Dong; Li, Na; He, Lian-Ping

2014-01-01

Accumulation of acaroid mites in the filters of air-conditioners is harmful to human health. It is important to clarify the allergen components of mites from the filters of local air-conditioning system. The present study was to detect the allergen types in the filters of air-conditioners and assesse their allergenicity by asthmatic models. Sixty aliquots of dust samples were collected from air conditioning filters in civil houses in Wuhu area. Total protein was extracted from the dust samples using PBS and quantified by Bradford method. Allergens I and II were also detected by Western blot using primary antibody (anti-Der f1/2, Der p1/Der f2/Der p2, respectively). Ten aliquots of the positive samples were randomly selected for homogenization and sensitized the mice for developing asthmatic animal models. Total serum IgE level and IFN-γ, IL-4 and IL-5 in the bronchoalveolar lavage fluid (BALF). The allergenicity of the extraction was assessed using pathological sections developed from the mouse pulmonary tissues. The concentration of extract from the 60 samples was ranged from 4.37 μg/ml to 30.76 μg/ml. After analyzing with Western blot, 31 of 60 samples were positive for 4 allergens of acaroid mites, and yet 16 were negative. The levels of total IgE from serum IL-4 and IL-5 from the BALF in the experimental group were apparently higher than that of negative control and PBS group (P < 0.01), but there were no statistical difference compared to OVA group (P > 0.05). However,the IFN-γ level in BALF was lower compared with the negative control and PBS group (P < 0.05) but with the OVA group (P > 0.05). The pathological changes were evidently emerged in pulmonary tissues, which were similar to those of OVA group, compared with the PBS ground and negative controls. The air-conditioner filters in human dwellings of Wuhu area potentially contain the major group allergen 1 and 2 from D. farinae and D. pteronyssinus, which may be associated with seasonal prevalence of

Acaroid mite allergens from the filters of air-conditioning system in China

PubMed Central

Li, Chao-Pin; Guo, Wei; Zhan, Xiao-Dong; Zhao, Bei-Bei; Diao, Ji-Dong; Li, Na; He, Lian-Ping

2014-01-01

Accumulation of acaroid mites in the filters of air-conditioners is harmful to human health. It is important to clarify the allergen components of mites from the filters of local air-conditioning system. The present study was to detect the allergen types in the filters of air-conditioners and assesse their allergenicity by asthmatic models. Sixty aliquots of dust samples were collected from air conditioning filters in civil houses in Wuhu area. Total protein was extracted from the dust samples using PBS and quantified by Bradford method. Allergens I and II were also detected by Western blot using primary antibody (anti-Der f1/2, Der p1/Der f2/Der p2, respectively). Ten aliquots of the positive samples were randomly selected for homogenization and sensitized the mice for developing asthmatic animal models. Total serum IgE level and IFN-γ, IL-4 and IL-5 in the bronchoalveolar lavage fluid (BALF). The allergenicity of the extraction was assessed using pathological sections developed from the mouse pulmonary tissues. The concentration of extract from the 60 samples was ranged from 4.37 μg/ml to 30.76 μg/ml. After analyzing with Western blot, 31 of 60 samples were positive for 4 allergens of acaroid mites, and yet 16 were negative. The levels of total IgE from serum IL-4 and IL-5 from the BALF in the experimental group were apparently higher than that of negative control and PBS group (P < 0.01), but there were no statistical difference compared to OVA group (P > 0.05). However,the IFN-γ level in BALF was lower compared with the negative control and PBS group (P < 0.05) but with the OVA group (P > 0.05). The pathological changes were evidently emerged in pulmonary tissues, which were similar to those of OVA group, compared with the PBS ground and negative controls. The air-conditioner filters in human dwellings of Wuhu area potentially contain the major group allergen 1 and 2 from D. farinae and D. pteronyssinus, which may be associated with seasonal prevalence of

Analysis of Bisphenol A, Alkylphenols, and Alkylphenol Ethoxylates in NIST SRM 2585 and Indoor House Dust by Gas Chromatography-Tandem Mass Spectrometry (GC/MS/MS).

PubMed

Fan, Xinghua; Kubwabo, Cariton; Wu, Fang; Rasmussen, Pat E

2018-06-26

Background: Ingestion of house dust has been demonstrated to be an important exposure pathway to several contaminants in young children. These compounds include bisphenol A (BPA), alkylphenols (APs), and alkylphenol ethoxylates (APEOs). Analysis of these compounds in house dust is challenging because of the complex composition of the sample matrix. Objective: The objective was to develop a simple and sensitive method to measure BPA, APs, and APEOs in indoor house dust. Methods: An integrated method that involved solvent extraction using sonication, sample cleanup by solid-phase extraction, derivatization by 2,2,2-trifluoro- N -methyl- N -(trimethylsilyl)acetamide, and analysis by GC coupled with tandem MS was developed for the simultaneous determination of BPA, APs, and APEOs in NIST Standard Reference Material (SRM) 2585 (Organic contaminants in house dust) and in settled house dust samples. Results: Target analytes included BPA, 4- tert -octylphenol (OP), OP monoethoxylate, OP diethoxylate, 4- n -nonylphenol (4 n NP), 4 n NP monoethoxylate (4 n NP 1 EO), branched nonylphenol (NP), NP monoethoxylate, NP diethoxylate, NP triethoxylate, and NP tetraethoxylate. The method was sensitive, with method detection limits ranging from 0.05 to 5.1 μg/g, and average recoveries between 82 and 115%. All target analytes were detected in SRM 2585 and house dust except 4 n NP and 4 n NP 1 EO. Conclusions: The method is simple and fast, with high sensitivity and good reproducibility. It is applicable to the analysis of target analytes in similar matrixes, such as sediments, soil, and biosolids. Highlights: Values measured in SRM 2585 will be useful for future research in method development and method comparison.

Risk assessments of PAHs and Hg exposure via settled house dust and street dust, linking with their correlations in human hair.

PubMed

Wang, Wei; Wu, Fuyong; Zheng, Jinshu; Wong, Ming Hung

2013-12-15

Domestic energy, chemicals bioaccessibility and particle size were found as three critical factors for risk assessment of PAHs exposure via settled house dust (SHD) and street dust. ∑PAHs and Hg contained in SHD were significantly (p<0.01) higher in coal-burning households of Qingyang (8.45-121; 0.48-16.4 μg g(-1)) than households in Guangzhou (1.23-22.2; 0.004-10.6 μg g(-1)) and 90% coal-burning houses were estimated with unacceptable cancer risks (>10(-4)) via SHD exposure. The highest accumulation trend of PAHs and Hg were found in <63 μm particles, and different particle sizes resulted in large variations of the obtained risks (up to 10 fold). Bioaccessibility corrected PAHs led to a significant decrease on related cancer risks and decreased in the order of 1.9, 1.1, 0.6 and 0.4 μg g(-1) with the increase of particle sizes (<63, 63-100, 100-280, 280-2000 μm). Scalp hair was tested as an indicator of body burdens of PAHs (0.05-0.9 μg g(-1)) and Hg (0.04-1.6 μg g(-1)). Different PAHs profiles were found between PAHs in SHD and those of hair, indicating that exogenous exposure to PAHs adsorbed on dust was not the major source of hair PAHs. Copyright © 2013 Elsevier B.V. All rights reserved.

Distribution features of biological hazardous pollutants in residential environments in Korea.

PubMed

Lee, Cheol Min; Hong, Soo Jong; Kim, Yoon Shin; Park, Gee Yong; Nam Goung, Sun Ju; Kim, Kyung Hwan

2014-01-01

This research has been conducted continuously since 2009 as part of a cohort of studies examining relationships between asthma and genetic factors, dietary habits, and environmental factors. Based on data from environmental research on house dust mites and endotoxins, which are widely known as pollutants in bedding that cause asthma in pregnant women and children, this work was conducted to obtain basic data that can be used in future cohort studies that analyze links between distribution of biological hazards and physical features of residential environments. The detection rates of house dust mite allergens, Der p1 and Der f1, were 52.7 and 86.5%, respectively, indicating that Der f1 is a dominant species in domestic indoor environments. According to comparisons between concentrations of house dust mites and endotoxins in bedding of pregnant women and children, Der p1 and endotoxins showed significantly lower concentrations in bedding of pregnant women compared with those in bedding of children, whereas Der f1 showed no significant difference in concentration according to bedding.

The Potential for a Blood Test for Scabies

PubMed Central

Arlian, Larry G.; Feldmeier, Hermann; Morgan, Marjorie S.

2015-01-01

Background Scabies afflicts millions of people worldwide, but it is very difficult to diagnose by the usual skin scrape test, and a presumptive diagnosis is often made based on clinical signs such as rash and intense itch. A sensitive and specific blood test to detect scabies would allow a physician to quickly make a correct diagnosis. Objective Our objective was to profile the mite-specific antibodies present in the sera of patients with ordinary scabies. Methods Sera of 91 patients were screened for Ig, IgD, IgE, IgG and IgM antibodies to S. scabiei, as well as to the house dust mites Dermatophagoides farinae, D. pteronyssinus and Euroglyphus maynei. Results 45%, 27% and 2.2% of the patients had measurable amounts of mixed Ig, IgG and IgE that recognized scabies mite antigens. However, 73.6% of the scabies patients had serum IgM that recognized scabies proteins, and all except two of them also had IgM that recognized all of the three species of dust mites. No patient had serum antibody exclusively reactive to scabies mite antigens. Conclusions Co-sensitization or cross-reactivity between antigens from scabies and house dust mites confounds developing a blood test for scabies. PMID:26492406

House dust fungal communities' characterization: a double take on the six by sixty by six (6 × 60 × 6) project

NASA Astrophysics Data System (ADS)

Amaro, Raquel; Coelho, Sónia D.; Pastorinho, M. Ramiro; Taborda-Barata, Luís; Vaz-Patto, Maria A.; Monteiro, Marisa; Nepomuceno, Miguel C. S.; Lanzinha, Joăo C. G.; Teixeira, Joăo P.; Pereira, Cristiana C.; Sousa, Ana C. A.

2016-11-01

Fungi are a group of microbes that are found with particular incidence in the indoor environment. Their direct toxicity or capability of generating toxic compounds has been associated with a large number of adverse health effects, such as infectious diseases and allergies. Given that in modern society people spend a large part of their time indoors; fungal communities' characterization of this environmental compartment assumes paramount importance in the comprehension of health effects. House dust is an easy to obtain, time-integrative matrix, being its use in epidemiological studies on human exposure to environmental contaminants highly recommended. Furthermore, dust can carry a great variety of fungal content that undergoes a large number of processes that modulate and further complexify human exposure. Our study aims to identify and quantify the fungal community on house dust samples collected using two different methodologies (an approach not often seen in the literature): active (vacuum cleaner bags) and passive sampling (dust settled in petri dishes). Sampling was performed as part of the ongoing 6 × 60 × 6 Project in which six houses from Covilhă (Portugal), with building dates representative of six decades, were studied for a period of sixty days.

Sensitivity to the house dust mite and airway hyperresponsiveness in a young adult population.

PubMed

Obase, Y; Shimoda, T; Mitsuta, K; Matsuo, N; Matsuse, H; Kohno, S

1999-10-01

The pathogenic mechanisms of airway hyperresponsiveness (AHR) in asthma are unknown and only a few studies have examined the importance of sensitivity to antigens in AHR in young adults. We investigated the correlation between AHR and sensitivity to specific antigens, atopy, history of childhood asthma and spirometry in a young adult population. Based on the results of interviews with 447 students at our university, 308 non-smoker students were classified into six groups. Group 1 comprised subjects with intermittent mild bronchial asthma; group 2, subjects with history of childhood asthma; group 3, subjects with atopic disease, and a RAST score for Dermatophagoides farinae (Def) of > or = 2; group 4, normal subjects with a RAST score for Def of > or = 2; group 5, subjects with cedar pollinosis; and group 6, normal subjects. We measured AHR to methacholine (MCh), spirometry, immunoglobulin E-radioimmunosorbent test (IgE-RIST), IgE-radioallergosorbent test to six common antigens, eosinophil cationic protein (ECP), and eosinophil count in peripheral blood in each subject. Airway hyperresponsiveness to MCh did not correlate with IgE-RIST, eosinophil count, or ECP. The highest AHR to MCh was present in groups 1 and 2 and lowest in groups 5 and 6. Multiple regression analysis showed that sensitivity to Def was the only factor that significantly influenced AHR to MCh. Airway hyperresponsiveness to MCh of groups with a RAST score for Def of 0/1 was lower than groups with a RAST score of 2 to 6. Airway hyperresponsiveness to MCh did not correlate with the degree of positivity to Def antigen among positive sensitized groups (RAST score 2 to 6). Sensitivity to mite antigen may be important in the pathogenesis of AHR and Def is a major contributing antigen in young adults in Japan. Once asthma occurs, AHR remains positive for a long time even after the disappearance of asthma-related symptoms.

Are neighborhood-level characteristics associated with indoor allergens in the household?

PubMed

Rosenfeld, Lindsay; Rudd, Rima; Chew, Ginger L; Emmons, Karen; Acevedo-García, Dolores

2010-02-01

Individual home characteristics have been associated with indoor allergen exposure; however, the influence of neighborhood-level characteristics has not been well studied. We defined neighborhoods as community districts determined by the New York City Department of City Planning. We examined the relationship between neighborhood-level characteristics and the presence of dust mite (Der f 1), cat (Fel d 1), cockroach (Bla g 2), and mouse (MUP) allergens in the household. Using data from the Puerto Rican Asthma Project, a birth cohort of Puerto Rican children at risk of allergic sensitization (n = 261), we examined associations between neighborhood characteristics (percent tree canopy, asthma hospitalizations per 1,000 children, roadway length within 100 meters of buildings, serious housing code violations per 1000 rental units, poverty rates, and felony crime rates), and the presence of indoor allergens. Allergen cutpoints were used for categorical analyses and defined as follows: dust mite: >0.25 microg/g; cat: >1 microg/g; cockroach: >1 U/g; mouse: >1.6 microg/g. Serious housing code violations were statistically significantly positively associated with dust mite, cat, and mouse allergens (continuous variables), adjusting for mother's income and education, and all neighborhood-level characteristics. In multivariable logistic regression analyses, medium levels of housing code violations were associated with higher dust mite and cat allergens (1.81, 95%CI: 1.08, 3.03 and 3.10, 95%CI: 1.22, 7.92, respectively). A high level of serious housing code violations was associated with higher mouse allergen (2.04, 95%CI: 1.15, 3.62). A medium level of housing code violations was associated with higher cockroach allergen (3.30, 95%CI: 1.11, 9.78). Neighborhood-level characteristics, specifically housing code violations, appear to be related to indoor allergens, which may have implications for future research explorations and policy decisions.

Are Neighborhood-Level Characteristics Associated with Indoor Allergens in the Household?

PubMed Central

Rosenfeld, Lindsay; Rudd, Rima; Chew, Ginger L.; Emmons, Karen; Acevedo-García, Dolores

2010-01-01

Background Individual home characteristics have been associated with indoor allergen exposure; however, the influence of neighborhood-level characteristics has not been well-studied. We defined neighborhoods as community districts determined by the New York Department of City Planning. Objective We examined the relationship between neighborhood-level characteristics and the presence of dust mite (Der f 1), cat (Fel d 1), cockroach (Bla g 2), and mouse (MUP) allergens in the household. Methods Using data from the Puerto Rican Asthma Project, a birth cohort of Puerto Rican children at risk of allergic sensitization (n=261) we examined associations between neighborhood characteristics (percent tree canopy, asthma hospitalizations per 1000 children, roadway length within 100 meters of buildings, serious housing code violations per 1000 rental units, poverty rates, and felony crime rates) and the presence of indoor allergens. Allergen cutpoints were used for categorical analyses and defined as follows: dust mite: >0.25 μg/g; cat: >1 μg/g; cockroach: >1 U/g; mouse: >1.6 μg/g. Results Serious housing code violations were statistically significantly positively associated with dust mite, cat and mouse allergens (continuous variables), adjusting for mother's income and education, and all neighborhood-level characteristics. In multivariable logistic regression analyses, medium levels of housing code violations were associated with higher dust mite and cat allergens (1.81, 95%CI: 1.08, 3.03 and 3.10, 95%CI: 1.22, 7.92, respectively). A high level of serious housing code violations was associated with higher mouse allergen (2.04, 95%CI: 1.15, 3.62). A medium level of housing code violations was associated with higher cockroach allergen (3.30, 95%CI: 1.11, 9.78). Conclusions Neighborhood-level characteristics, specifically housing code violations, appear to be related to indoor allergens, which may have implications for future research explorations and policy decisions. PMID

Isomer Profiles of Perfluorochemicals in Matched Maternal, Cord, and House Dust Samples: Manufacturing Sources and Transplacental Transfer

PubMed Central

Beesoon, Sanjay; Webster, Glenys M.; Shoeib, Mahiba; Harner, Tom; Benskin, Jonathan P.

2011-01-01

Background: Perfluorochemicals (PFCs) are detectable in the general population and in the human environment, including house dust. Sources are not well characterized, but isomer patterns should enable differentiation of historical and contemporary manufacturing sources. Isomer-specific maternal–fetal transfer of PFCs has not been examined despite known developmental toxicity of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in rodents. Objectives: We elucidated relative contributions of electrochemical (phased out in 2001) and telomer (contemporary) PFCs in dust and measured how transplacental transfer efficiency (TTE; based on a comparison of maternal and cord sera concentrations) is affected by perfluorinated chain length and isomer branching pattern. Methods: We analyzed matching samples of house dust (n = 18), maternal sera (n = 20), and umbilical cord sera (n = 20) by isomer-specific high-performance liquid chromatography tandem mass spectrometry. Results: PFOA isomer signatures revealed that telomer sources accounted for 0–95% of total PFOA in house dust (median, 31%). This may partly explain why serum PFOA concentrations are not declining in some countries despite the phase-out of electrochemical PFOA. TTE data indicate that total branched isomers crossed the placenta more efficiently than did linear isomers for both PFOS (p < 0.01) and PFOA (p = 0.02) and that placental transfer of branched isomers of PFOS increased as the branching point moved closer to the sulfonate (SO3–) end of the molecule. Conclusions: Results suggest that humans are exposed to telomer PFOA, but larger studies that also account for dietary sources should be conducted. The exposure profile of PFOS and PFOA isomers can differ between the mother and fetus—an important consideration for perinatal epidemiology studies of PFCs. PMID:21757419

Heavy metals in food, house dust, and water from an e-waste recycling area in South China and the potential risk to human health.

PubMed

Zheng, Jing; Chen, Ke-hui; Yan, Xiao; Chen, She-Jun; Hu, Guo-Cheng; Peng, Xiao-Wu; Yuan, Jian-gang; Mai, Bi-Xian; Yang, Zhong-Yi

2013-10-01

Concentrations of heavy metals (Cd, Pb, Cu, Zn, and Ni) were measured in the foodstuffs, house dust, underground/drinking water, and soil from an electronic waste (e-waste) area in South China. Elevated concentrations of these potentially toxic metals were observed in the samples but not in drinking water. The health risks for metal exposure via food consumption, dust ingestion, and drinking water were evaluated for local residents. For the average residents in the e-waste area, the non-carcinogenic risks arise predominantly from rice (hazard index=3.3), vegetables (2.2), and house dust (1.9) for adults, while the risks for young children are dominated by house dust (15). Drinking water may provide a negligible contribution to risk. However, local residents who use groundwater as a water supply source are at high non-carcinogenic risk. The potential cancer risks from oral intake of Pb are 8×10(-5) and 3×10(-4) for average adults and children, and thus groundwater would have a great potential to induce cancer (5×10(-4) and 1×10(-3)) in a highly exposed population. The results also reveal that the risk from oral exposure is much higher than the risk from inhalation and dermal contact with house dust. Copyright © 2013 Elsevier Inc. All rights reserved.

Per- and polyfluorinated compounds (PFCs) in house dust and indoor air in Catalonia, Spain: implications for human exposure.

PubMed

Ericson Jogsten, I; Nadal, M; van Bavel, B; Lindström, G; Domingo, J L

2012-02-01

A total of 27 per- and polyfluorinated compounds (PFCs) were determined in both house dust (n=10) and indoor air (n=10) from selected homes in Catalonia, Spain. Concentrations were found to be similar or lower than those previously reported for household microenvironments in other countries. Ten PFCs were detected in all house dust samples. The highest mean concentrations corresponded to perfluorodecanoic acid (PFDA) and perfluorononanoic acid (PFNA), 10.7 ng/g (median: 1.5 ng/g) and 10.4 ng/g (median: 5.4 ng/g), respectively, while the 8:2 fluorotelomer alcohol (FTOH) was the dominating neutral PFC at a concentration of 0.41 ng/g (median: 0.35 ng/g). The indoor air was dominated by the FTOHs, especially the 8:2 FTOH at a mean (median) concentration of 51 pg/m(3) (median: 42 pg/m(3)). A limited number of ionic PFCs were also detected in the indoor air samples. Daily intakes of PFCs were estimated for average and worst case scenarios of human exposure from indoor sources. For toddlers, this resulted in average intakes of ∑ionic PFCs of 4.9ng/day (0.33 ng/kg(bw)/day for a 15 kg toddlers) and ∑neutral PFCs of 0.072 ng/day (0.005 ng/kg(bw)/day) from house dust. For adults, the average daily intakes of dust were 3.6 and 0.053 ng/day (0.05 and 0.001 ng/kg(bw)/day for a 70 kg adult) for ∑ionic and ∑neutral PFCs, respectively. The average daily inhalation of ∑neutral PFCs was estimated to be 0.9 and 1.3 ng/day (0.06 and 0.02 ng/kg(bw)/day) for toddlers and adults, respectively. For PFOS, the main ionic PFC detected in indoor air samples, the median intakes (based on those samples where PFOS was detected), resulted in indoor exposures of 0.06 and 0.11 ng/day (0.004 and 0.002 ng/kg(bw)/day) for toddlers and adults, respectively. Based on previous studies on dietary intake and drinking water consumption, both house dust and indoor air contribute significantly less to PFC exposure within this population. Copyright © 2011 Elsevier Ltd. All rights reserved.

Impeding movement of the poultry red mite, Dermanyssus gallinae.

PubMed

Pritchard, James; Küster, Tatiana; George, David; Sparagano, Olivier; Tomley, Fiona

2016-07-30

The poultry red mite, Dermanyssus gallinae, is an economically important hematophagous parasite of commercial egg laying hens, also affecting domesticated birds and companion animals. Conventional control of D. gallinae through acaricidal spraying is often ineffective, creating an urgent need to identify alternative management strategies for commercial and domestic infestations. Whilst integrated pest management is being considered for D. gallinae, the potential of impeding mite 'migration' routes, to either prevent initial infestation or manage established populations, has not been researched. Here we demonstrate that barriers of insecticidal glue, double sided sticky tape and thyme oil can contain D. gallinae within a specified area of a petri dish (78-88% of total mite population) and this level of containment was significantly greater than for negative controls (p values <0.05). Further studies in poultry houses are recommended to investigate the efficacy of these barriers in real world application and identity potential for barriers as a strategy for mite control. Copyright © 2016 Elsevier B.V. All rights reserved.

House dust exposure mediates gut microbiome Lactobacillus enrichment and airway immune defense against allergens and virus infection.

PubMed

Fujimura, Kei E; Demoor, Tine; Rauch, Marcus; Faruqi, Ali A; Jang, Sihyug; Johnson, Christine C; Boushey, Homer A; Zoratti, Edward; Ownby, Dennis; Lukacs, Nicholas W; Lynch, Susan V

2014-01-14

Exposure to dogs in early infancy has been shown to reduce the risk of childhood allergic disease development, and dog ownership is associated with a distinct house dust microbial exposure. Here, we demonstrate, using murine models, that exposure of mice to dog-associated house dust protects against ovalbumin or cockroach allergen-mediated airway pathology. Protected animals exhibited significant reduction in the total number of airway T cells, down-regulation of Th2-related airway responses, as well as mucin secretion. Following dog-associated dust exposure, the cecal microbiome of protected animals was extensively restructured with significant enrichment of, amongst others, Lactobacillus johnsonii. Supplementation of wild-type animals with L. johnsonii protected them against both airway allergen challenge or infection with respiratory syncytial virus. L. johnsonii-mediated protection was associated with significant reductions in the total number and proportion of activated CD11c(+)/CD11b(+) and CD11c(+)/CD8(+) cells, as well as significantly reduced airway Th2 cytokine expression. Our results reveal that exposure to dog-associated household dust results in protection against airway allergen challenge and a distinct gastrointestinal microbiome composition. Moreover, the study identifies L. johnsonii as a pivotal species within the gastrointestinal tract capable of influencing adaptive immunity at remote mucosal surfaces in a manner that is protective against a variety of respiratory insults.

House dust exposure mediates gut microbiome Lactobacillus enrichment and airway immune defense against allergens and virus infection

PubMed Central

Fujimura, Kei E.; Demoor, Tine; Rauch, Marcus; Faruqi, Ali A.; Jang, Sihyug; Johnson, Christine C.; Boushey, Homer A.; Zoratti, Edward; Ownby, Dennis; Lukacs, Nicholas W.; Lynch, Susan V.

2014-01-01

Exposure to dogs in early infancy has been shown to reduce the risk of childhood allergic disease development, and dog ownership is associated with a distinct house dust microbial exposure. Here, we demonstrate, using murine models, that exposure of mice to dog-associated house dust protects against ovalbumin or cockroach allergen-mediated airway pathology. Protected animals exhibited significant reduction in the total number of airway T cells, down-regulation of Th2-related airway responses, as well as mucin secretion. Following dog-associated dust exposure, the cecal microbiome of protected animals was extensively restructured with significant enrichment of, amongst others, Lactobacillus johnsonii. Supplementation of wild-type animals with L. johnsonii protected them against both airway allergen challenge or infection with respiratory syncytial virus. L. johnsonii-mediated protection was associated with significant reductions in the total number and proportion of activated CD11c+/CD11b+ and CD11c+/CD8+ cells, as well as significantly reduced airway Th2 cytokine expression. Our results reveal that exposure to dog-associated household dust results in protection against airway allergen challenge and a distinct gastrointestinal microbiome composition. Moreover, the study identifies L. johnsonii as a pivotal species within the gastrointestinal tract capable of influencing adaptive immunity at remote mucosal surfaces in a manner that is protective against a variety of respiratory insults. PMID:24344318

Storage mite contamination of commercial dry dog food in south-eastern Australia.

PubMed

Hibberson, C E; Vogelnest, L J

2014-06-01

To evaluate contamination of unopened and opened stored sources of commercial dry dog food by viable storage mites. Prospective laboratory and field study. Samples were collected from nine brands of previously unopened bags (new bags) of dry food and 20 field sources of stored dry food in homes in Sydney and Canberra, Australia. All samples were initially examined for the presence of mites using a stereo-binocular microscope and then placed in separate filter-paper-sealed containers. Field samples were incubated at an average temperature of 29°C and 78% relative humidity (RH) for 5 weeks and then at average 26°C/83% RH for 8 weeks. Paired new-bag samples were stored under room conditions (average 23°C/47% RH) and controlled incubator conditions (average 26°C/80% RH) for 6 weeks. All samples were thoroughly examined for mites, mite eggs and visible mould once weekly using a stereo-binocular microscope. Storage mites were not visualised in any of the field samples or in new-bag samples stored at room temperature. Storage mites, identified as Tyrophagus putrescentiae, were visualised in increasing numbers in seven of nine new-bag samples after incubation, with first mites and then eggs evident after 3 weeks of incubation. We confirmed the presence of viable storage mites in a range of previously unopened commercial dry dog foods in Australia and confirmed the possibility of heavy storage mite contamination for dry food stored under conditions of moderate temperature and high humidity. These findings have relevance to storage mite and/or dust mite sensitivity in canine atopic dermatitis. © 2014 Australian Veterinary Association.

Dermanyssus gallinae (chicken mite): an underdiagnosed environmental infestation.

PubMed

Collgros, H; Iglesias-Sancho, M; Aldunce, M J; Expósito-Serrano, V; Fischer, C; Lamas, N; Umbert-Millet, P

2013-06-01

Dermanyssus gallinae is a mite that normally parasitizes small birds but may occasionally bite humans. We report an unusual case of an 82-year-old woman who presented with pruritus and bite-like lesions over her trunk. Other members of the household were also affected. On physical examination, mites < 1 mm in size were found on the patient's body. The family were residing in the city centre and had no pets, but there were pigeon nests in close proximity to the house. Most dermatologists have difficulties identifying ectoparasitosis. In the case of D. gallinae, the small size of the mites and the fact that they leave the host after feeding means that they may not be seen at presentation, thus such infestations are likely to be underdiagnosed. Physicians should be aware that infection with this mite is possible even in patients from urban areas, and it should be included in the differential diagnosis of conditions causing recurrent pruritus unresponsive to standard treatments. © The Author(s) CED © 2013 British Association of Dermatologists.

Phthalate concentrations in house dust in relation to autism spectrum disorder and developmental delay in the CHildhood Autism Risks from Genetics and the Environment (CHARGE) study.

PubMed

Philippat, Claire; Bennett, Deborah H; Krakowiak, Paula; Rose, Melissa; Hwang, Hyun-Min; Hertz-Picciotto, Irva

2015-06-26

Phthalates are endocrine-disrupting chemicals that influence thyroid hormones and sex steroids, both critical for brain development. We studied phthalate concentrations in house dust in relation to the risks of developing autism spectrum disorder (ASD) or developmental delay (DD). Participants were a subset of children from the CHARGE (CHildhood Autism Risks from Genetics and the Environment) case-control study. ASD and DD cases were identified through the California Department of Developmental Services system or referrals; general population controls were randomly sampled from state birth files and frequency-matched on age, sex, and broad geographic region to ASD cases. All children (50 ASD, 27 DD, 68 typically developing (TD)) were assessed with Mullen Scales of Early Learning, Vineland Adaptive Behavior Scales (VABS) and Aberrant Behavior Checklist. We measured 5 phthalates in dust collected in the child's home using a high volume small surface sampler. None of the phthalates measured in dust was associated with ASD. After adjustment, we observed greater di(2-ethylhexyl) phthalate (DEHP) and butylbenzyl phthalate (BBzP) concentrations in indoor dust from homes of DD children: Odds ratios (OR) were 2.10 (95% confidence interval (CI); 1.10; 4.09) and 1.40 (95% CI; 0.97; 2.04) for a one-unit increase in the ln-transformed DEHP and BBzP concentrations, respectively. Among TD children, VABS communication, daily living, and adaptive composite standard scores were lower, in association with increased diethyl phthalate (DEP) concentrations in dust. Participants with higher dibutyl phthalate (DBP) concentrations in house dust also trended toward reduced performance on these subscales. Among ASD and DD boys, higher indoor dust concentrations of DEP and DBP were associated with greater hyperactivity-impulsivity and inattention. House dust levels of phthalates were not associated with ASD. The inability to distinguish past from recent exposures in house dust and the fact

Patch test reactions to mite antigens: a GERDA multicentre study. Groupe d'Etudes et de Recherches en Dermato-Allergie.

PubMed

Castelain, M; Birnbaum, J; Castelain, P Y; Ducombs, G; Grosshans, E; Jelen, G; Lacroix, M; Meynadier, J; Mougeolle, J M; Lachapelle, J M

1993-11-01

We performed patch tests with Dermatophagoides pteronyssinus (Dp) antigens from 2 different sources in 355 non-randomly selected patients with atopic dermatitis (AD) and 398 subjects of a control group. The study demonstrated that contact sensitization to mites occurred in an appreciable % of AD cases (20.8%), using commonly available assay products. The differences recorded between the 2 materials tested were related to the concentration of P1 antigen. Non-atopic patients rarely showed positive reactions to Dp (0.75%), when strict criteria for readings were applied and if 2 readings were performed. Patients with positive patch tests did not necessarily show positive immediate skin tests. It would be useful to carry out tests systematically in atopic patients, even if it is not yet known what modern treatment would be best for the patient. Laboratories still do not provide standardized house dust mite preparations--measuring and codifying their biological activity--for use in patch tests. It is to be hoped that the extension of this type of test will lead to the production of better test materials, in syringes with homogeneous dispersion and concentration.

The unfavorable effects of concomitant asthma and sleeplessness due to the atopic eczema/dermatitis syndrome (AEDS) on quality of life in subjects allergic to house-dust mites.

PubMed

Terreehorst, I; Duivenvoorden, H J; Tempels-Pavlica, Z; Oosting, A J; de Monchy, J G R; Bruijnzeel-Koomen, C A F M; Post, M W M; Gerth van Wijk, R

2002-10-01

Allergic rhinitis, asthma or the atopic eczema/dermatitis syndrome (AEDS) may independently impair quality of life in patients. However, although many allergic patients may suffer from more than one disorder, the effect of concomitant disease -- in particular, the impact of AEDS -- is largely unknown. As part of a large multicenter clinical trial on the efficacy of mattress casings in house-dust mite (HDM) allergy, generic quality of life in a mixed population of 224 subjects with rhinitis (n = 198) and/or asthma (n = 111) and/or AEDS (n = 64) was studied. The study aimed to estimate quality of life impairment in these atopic patients and to address the question/issue of whether one atopic disorder goes beyond other existing allergic diseases, thereby causing further impairment to quality of life. Generic quality of life was assessed by SF-36. Quality of life in the atopic group was compared with a Dutch norm population. Multiple linear regression was used to determine the effects of disease (i.e. the presence of allergic rhinitis, asthma or AEDS) or disease severity, as assessed by visual analog scores (VAS) for asthma, rhinitis, VAS sleeplessness and VAS itching being considered as major symptoms in AEDS on SF-36 domains. Compared to the norm group, atopic patients were impaired in: physical functioning; role physical functioning; general health; vitality; and social functioning. The diagnosis of asthma was negatively associated with the SF-36 subscales for physical functioning (P = 0.02), and general health (P < 0.01). In line with these findings, asthma severity (VAS asthma) was negatively associated with physical functioning (P < 0.01), role physical functioning (P < 0.01), general health (P < 0.0.1), social functioning (P = 0.01), emotional functioning (P = 0.01), and vitality (P = 0.01). VAS sleeplessness had significant negative effect on role physical functioning (P < 0.01), bodily pain (P < 0.01), General health (P = 0.01), mental health (P < 0

Rare earth elements and select actinoids in the Canadian House Dust Study.

PubMed

Rasmussen, P E; Levesque, C; Chénier, M; Gardner, H D

2017-09-01

Nationally representative baseline data are presented for rare earth elements (REE), thorium (Th) and uranium (U) in house dust sampled from 1025 urban homes, in units of concentrations (μg g -1 ), loadings (μg m -2 ), and loading rates (ng m -2  d -1 ). Spearman rank correlations indicate that, in addition to outdoor sources, consumer products and building materials can influence indoor dust concentrations of REE, Th, and U. Correlations (P<.01) with numbers of occupants, dogs, and cats suggest soil track-in. Correlations (P<.01) with hardwood floors suggest release of REE additives used in pigments and coatings during daily wear and tear. Concentrations of light REE are elevated in smokers' homes compared to non-smokers' homes (P<.001), suggesting that a key source is "mischmetal," the REE alloy used in cigarette-lighter flints. Indoor sources include geological impurities in raw materials used in consumer products, such as U and Th impurities in bentonite clay used in cat litter, and REE impurities in phosphates used for a variety of applications including dog food and building materials. Median gastric bioaccessibility (pH 1.5) of most REE in dust ranges from about 20% to 29%. Household vacuum samples correlate with fresh dust samples from the same homes (P<.001 for all investigated elements). © 2017 Her Majesty the Queen in Right of Canada Indoor Air © 2017 John Wiley & Sons Ltd.

Risk assessment of non-dietary exposure to polycyclic aromatic hydrocarbons (PAHs) via house PM2.5, TSP and dust and the implications from human hair

NASA Astrophysics Data System (ADS)

Wang, Wei; Huang, Min-juan; Chan, Chuen-Yu; Cheung, Kwai Chung; Wong, Ming Hung

2013-07-01

To evaluate the cancer risk due to non-dietary PAHs exposure in home environment (inhalation and ingestion), exposure to fine particles (PM2.5) and polycyclic aromatic hydrocarbons (PAHs) of PM2.5, total suspend particles (TSP) and dust in homes at two urban centers of Pearl River Delta were assessed. House PM2.5 bound PAHs in Guangzhou (GZ) ranged from 10.0 to 61.9 ng m-3 and 0.72 to 8.15 ng m-3 in Hong Kong (HK). PAH profiles found in PM2.5, TSP and dust were different than that in hair (dominated by Nap and Phe). Pyr and Flu in house dust significantly correlated with that in hair (r = 0.69; 0.55, p < 0.05) but no correlation was found between PAHs in hair and PM2.5. High correlation coefficients (r2 = 0.97/0.95, p < 0.01) were noted between dibenzo(a,h)anthracene (DBA) and Toxicity Equivalent Concentrations (TEQs) of dust and PM2.5. The lung cancer risks based on PM2.5 bound PAHs exposure in houses of GZ (10-5-10-4) were significantly higher than those of HK (10-6-10-5), which were also significantly higher than the cancer risks associated with house dust intake (10-7-10-5) in GZ. PAHs exposure via non-dietary route (PM2.5 and dust) was found to be 1-3 times higher than fish consumption for children and contributed to 52-76% of total PAHs intake for children and 24-50% for adults in GZ.

Grain dust and the lungs.

PubMed Central

Chan-Yeung, M.; Ashley, M. J.; Grzybowski, S.

1978-01-01

Grain dust is composed of a large number of materials, including various types of grain and their disintegration products, silica, fungi, insects and mites. The clinical syndromes described in relation to exposure to grain dust are chronic bronchitis, grain dust asthma, extrinsic allergic alveolitis, grain fever and silo-filler's lung. Rhinitis and conjunctivitis are also common in grain workers. While the concentration and the quality of dust influence the frequency and the type of clinical syndrome in grain workers, host factors are also important. Of the latter, smoking is the most important factor influencing the frequency of chronic bronchitis. The role of atopy and of bronchial hyperreactivity in grain dust asthma has yet to be assessed. Several well designed studies are currently being carried out in North America not only to delineate the frequency of the respiratory abnormalities, the pathogenetic mechanisms and the host factors, but also to establish a meaningful threshold limit concentration for grain dust. Images p1272-a PMID:348288

[Polychlorinated biphenyls in house dust at an e-waste site and urban site in the Pearl River Delta, southern China: sources and human exposure and health risks].

PubMed

Zhu, Zhi-Cheng; Chen, She-Jun; Ding, Nan; Wang, Jing; Luo, Xiao-Jun; Mai, Bi-Xian

2014-08-01

Polychlorinated biphenyls (PCBs) were measured in house dust from an e-waste site and urban site in the Pearl River Delta, southern China. The PCB concentrations in house dust at the e-waste site ranged from 12.4 to 87 765 ng x g(-1), with an average of 10 167 ng x g(-1). There was no significant difference in the PCB concentrations between indoor and outdoor dust. The PCB homologue pattern was dominated by tri-, penta-, hexa-, and tetra-CBs, which was not similar to that in Chinese technical PCB product. There was also no significant difference in the PCB compositions between indoor and outdoor dust. PCB sources in house dust at the e-waste site were apportioned by chemical mass balance (CMB) model. The results showed that the PCBs were derived primarily from Aroclor 1262 (36.7% ), Aroclor 1254 (26.7%), Aroclor 1242 (21.4%), and Aroclor 1248 (18.5%). The daily exposure doses were 42, 17, and 2.9 ng x (kg x d)(-1) for toddlers, children/adolescents, and adults in the e-waste area, respectively. Risk assessment indicated that the hazard quotients were higher than 1 for toddlers and children/adolescents indicating adverse effects for them. The lifetime average excess carcinogenic risk for population in the e-waste area was 4.5 x 10(-5), within the acceptable range of U. S. Environmental Protection Agency. The mean concentrations of PCBs in house dust in Guangzhou was 48.7 ng x g(-1). The low PCB level is consistent with the fact that technical PCBs were not widely used in China in the past. The risks of exposure to PCBs via house dust in Guangzhou are very low.

Investigating relationships between biomarkers of exposure and environmental copper and manganese levels in house dusts from a Portuguese industrial city.

PubMed

Reis, A P; Costa, S; Santos, I; Patinha, C; Noack, Y; Wragg, J; Cave, M; Sousa, A J

2015-08-01

This study reports on data obtained from a pilot survey focusing on house dust and toenail metal(loids) concentrations in residents living in the industrial city of Estarreja. The study design hereby described aims at investigating relationships between human toenails and both copper and manganese levels in settled house dusts. A total of 21 households and 30 individuals were recruited for the pilot study: 19 households corresponding to 27 residents living near the industrial complex, forming the exposed group, plus 2 households and 3 residents from residential areas with no anticipated environmental contaminants that were used for comparison. Factorial analysis was used for source identification purposes. Investigation on the potential influence of environmental factors over copper and manganese levels in the toenails was carried out via questionnaire data and multiple correspondence analysis. The results show that copper concentrations are more elevated in the indoor dusts, while manganese concentrations are more elevated in the outdoor dust samples. The geometrical relationships in the datasets suggest that the backyard soil is a probable source of manganese to the indoor dust. Copper and manganese contents in the toenail clippings are more elevated in children than in adults, but the difference between the two age groups is not statistically significant (p > 0.05). Investigation of environmental factors influencing the exposure-biomarker association indicates a probable relationship between manganese contents in indoor dust and manganese levels in toenail clippings, a result that is partially supported by the bioaccessibility estimates. However, for copper, no relationship was found between indoor dusts and the biomarkers of exposure.

Suppressive effect of an aqueous extract of Diospyros kaki calyx on dust mite extract/2,4-dinitrochlorobenzene-induced atopic dermatitis-like skin lesions.

PubMed

Yu, Ju-Hee; Jin, Meiling; Choi, Young-Ae; Jeong, Na-Hee; Park, Jeong-Sook; Shin, Tae-Yong; Kim, Sang-Hyun

2017-08-01

Atopic dermatitis (AD) is a common chronic inflammatory skin disease, affecting 10-20% of individuals worldwide. Therefore, the discovery of drugs for treating AD is an attractive subject and important to human health. Diospyros kaki and Diospyros kaki (D. kaki) folium exert beneficial effects on allergic inflammation. However, the effect of D. kaki calyx on AD remains elusive. The present study evaluated the effects of an aqueous extract of D. kaki calyx (AEDKC) on AD-like skin lesions using mouse and keratinocyte models. We used a mouse AD model by the repeated skin exposure of house dust mite extract [Dermatophagoides farinae extract (DFE)] and 2,4-dinitrochlorobenzene (DNCB) to the ears. In addition, to determine the underlying mechanism of its operation, tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)-activated keratinocytes (HaCaT) were used. Oral administration of AEDKC decreased AD-like skin lesions, as demonstrated by the reduced ear thickness, serum immunoglobulin E (IgE), DFE-specific IgE, IgG2a, histamine level and inflammatory cell infiltration. AEDKC inhibited the expression of pro-inflammatory cytokines and a chemokine via downregulation of nuclear factor-κB and signal transducer and activator of transcription 1 in HaCaT cells. On examination of the AD-related factors in vivo and in vitro, it was confirmed that AEDKC decreased AD-like skin lesions. Taken together, the results suggest that AEDKC is a potential drug candidate for the treatment of AD.

After the PBDE Phase-Out: A Broad Suite of Flame Retardants in Repeat House Dust Samples from California

PubMed Central

2012-01-01

Higher house dust levels of PBDE flame retardants (FRs) have been reported in California than other parts of the world, due to the state’s furniture flammability standard. However, changing levels of these and other FRs have not been evaluated following the 2004 U.S. phase-out of PentaBDE and OctaBDE. We analyzed dust collected in 16 California homes in 2006 and again in 2011 for 62 FRs and organohalogens, which represents the broadest investigation of FRs in homes. Fifty-five compounds were detected in at least one sample; 41 in at least 50% of samples. Concentrations of chlorinated OPFRs, including two (TCEP and TDCIPP) listed as carcinogens under California’s Proposition 65, were found up to 0.01% in dust, higher than previously reported in the U.S. In 75% of the homes, we detected TDBPP, or brominated “Tris,” which was banned in children’s sleepwear because of carcinogenicity. To our knowledge, this is the first report on TDBPP in house dust. Concentrations of Firemaster 550 components (EH-TBB, BEH-TEBP, and TPHP) were higher in 2011 than 2006, consistent with its use as a PentaBDE replacement. Results highlight the evolving nature of FR exposures and suggest that manufacturers continue to use hazardous chemicals and replace chemicals of concern with chemicals with uncharacterized toxicity. PMID:23185960

In vitro efficacy of ByeMite and Mite-Stop on developmental stages of the red chicken mite Dermanyssus gallinae.

PubMed

Abdel-Ghaffar, Fathy; Semmler, Margit; Al-Rasheid, Khaled; Mehlhorn, Heinz

2009-10-01

The present in vitro study shows the efficacy of two antimite products (ByeMite = phoxim, Mite-Stop = neem seed extract) against all developing stages of the important red chicken mite Dermanyssus gallinae (obtained at two farms in France and Germany). While permanent contact with the active compound led to an efficacy of 100% in the case of Mite-Stop on mites in both farms, there was only a 96.2% killing effect of ByeMite on the mites of the French farm. Even short contacts of only 4 s killed 100% of mites in the case of Mite-Stop at the French farm and only 84.5% in the German farm. ByeMite, on the other hand, killed only 27.8% (Germany) and 30% (France) when mites got the chance to escape from the treated grounds to untreated ones. When using only the half doses of both products, Mite-Stop(R) still reached, after permanent contact, 100% activity on the German farm and 98.2% in France, while ByeMite killed 93.8% (Germany) and 90.6% (France). Short contact to half doses of course reduced the activity of both products (Mite-Stop = 59.3% in France, 22.1% in Germany; ByeMite = 28.8% in France, 18.8% in Germany). With respect to the fumigant activity of the products, the strains of D. gallinae reacted differently. While Mite-Stop(R) showed a clear fumigant activity in the case of the German mites, this product did not affect the French mites by air distribution, neither did ByeMite in both cases. Therefore, mites have to come in contact with both products. Against Mite-Stop, there was apparently no resistance and low doses have high efficacy after even short contacts, which regularly occur in a treated stable, where mites have the chance to leave treated places to untreated hidden spots.

Monitoring Indoor Exposure to Organophosphate Flame Retardants: Hand Wipes and House Dust

PubMed Central

Hoffman, Kate; Garantziotis, Stavros; Birnbaum, Linda S.

2014-01-01

: hand wipes and house dust. Environ Health Perspect 123:160–165; http://dx.doi.org/10.1289/ehp.1408669 PMID:25343780

Air

MedlinePlus

... cause outdoor air pollution! Indoor pollutants Outdoor pollutants Animal dander (skin and fur) Ground-level ozone (smog) Dust mites Dust* Cockroaches Dirt* Mold Smoke* Secondhand smoke Liquids* Pesticides (either tracked in from outside or used in the house) Industrial emissions (like smoke and ...

Protocols for the delivery of small molecules to the two-spotted spider mite, Tetranychus urticae

PubMed Central

Nunes, Maria Andreia; Zhurov, Vladimir; Dermauw, Wannes; Osakabe, Masahiro; Van Leeuwen, Thomas; Grbic, Miodrag

2017-01-01

The two-spotted spider mite, Tetranychus urticae, is a chelicerate herbivore with an extremely wide host range and an extraordinary ability to develop pesticide resistance. Due to its responsiveness to natural and synthetic xenobiotics, the spider mite is becoming a prime pest herbivore model for studies of the evolution of host range, plant-herbivore interactions and mechanisms of xenobiotic resistance. The spider mite genome has been sequenced and its transcriptional responses to developmental and various biotic and abiotic cues have been documented. However, to identify biological and evolutionary roles of T. urticae genes and proteins, it is necessary to develop methods for the efficient manipulation of mite gene function or protein activity. Here, we describe protocols developed for the delivery of small molecules into spider mites. Starting with mite maintenance and the preparation of the experimental mite populations of developmentally synchronized larvae and adults, we describe 3 methods for delivery of small molecules including artificial diet, leaf coating, and soaking. The presented results define critical steps in these methods and demonstrate that they can successfully deliver tracer dyes into mites. Described protocols provide guidelines for high-throughput setups for delivery of experimental compounds that could be used in reverse genetics platforms to modulate gene expression or protein activity, or for screens focused on discovery of new molecules for mite control. In addition, described protocols could be adapted for other Tetranychidae and related species of economic importance such as Varroa, dust and poultry mites. PMID:28686745

Nedocromil sodium inhibits antigen-induced contraction of human lung parenchymal and bronchial strips, and the release of sulphidopeptide-leukotriene and histamine from human lung fragments.

PubMed Central

Napier, F. E.; Shearer, M. A.; Temple, D. M.

1990-01-01

1. The effects of nedocromil sodium on antigen-induced release of sulphidopeptide-leukotrienes and histamine from passively sensitized fragments of human lung, and on antigen-induced contraction of sensitized strips of human lung parenchyma and bronchus, have been studied. 2. Nedocromil sodium 0.1 and 1 microM inhibited leukotriene release from fragments of human lung by 30% and 38% respectively, and histamine release by 43% for both concentrations, but 10 microM was ineffective. The lung fragments, which were passively sensitized to house dust mite, Dermataphagoides pteronyssinus, in control experiments released leukotrienes (6.58 +/- 0.12 nmol equiv. leukotriene C4 per g, n = 6) and histamine (10.3 +/- 1.8 of total tissue histamine, n = 5) when challenged with house dust mite extract. 3. Isolated strips of human lung parenchyma, passively sensitized to D. pteronyssinus, contracted when treated with house dust mite extract to a mean value of 40% of the maximal histamine response for each strip. Nedocromil sodium 0.1 and 1 microM inhibited these contractions by 50% and 70% of the control response, but 10 microM had no inhibitory effect. 4. Isolated rings from human bronchus, also passively sensitized to D. pteronyssinus, contracted when treated with house dust mite extract to a mean value of 86% of the maximal histamine response. Nedocromil sodium 1 microM, but not 0.1 or 10 microM, inhibited contractions by 48% of the control response. 5. The therapeutic effects of nedocromil sodium in allergic asthma may depend, partly, on its inhibition of antigen-induced release of leukotrienes and histamine in human lung and its consequent inhibition of antigen-induced contractions of parenchymal and bronchial tissue. PMID:1696152

Temporal changes in distribution, prevalence and intensity of northern fowl mite (Ornithonyssus sylviarum) parasitism in commercial caged laying hens, with a comprehensive economic analysis of parasite impact.

PubMed

Mullens, Bradley A; Owen, Jeb P; Kuney, Douglas R; Szijj, Coralie E; Klingler, Kimberly A

2009-03-09

Establishment and spread of Ornithonyssus sylviarum were documented through time on sentinel hens (50 per house of 28,000-30,000 hens) in the first egg production cycle of three large commercial flocks (12 houses) of white leghorn hens. Mites were controlled using acaricide, and the impacts of treatment on mite populations and economic performance were documented. Mite prevalence and intensity increased rapidly and in tandem for 4-8 weeks after infestation. Intensity declined due to immune system involvement, but prevalence remained high, and this would affect mite sampling plan use and development. Early treatment was more effective at controlling mites; 85% of light infestations were eliminated by a pesticide spray (Ravap), versus 24% of heavy infestations. Hens infested later developed lower peak mite intensities, and those mite populations declined more quickly than on hens infested earlier in life. Raw spatial association by distance indices (SADIE), incorporating both the intensity and distribution of mites within a house, were high from week-to-week within a hen house. Once adjusted spatially to reflect variable hen cohorts becoming infested asynchronously, this analysis showed the association index tended to rebound at intervals of 5-6 weeks after the hen immune system first suppressed them. Large, consistent mite differences in one flock (high vs. low infestation levels) showed the economic damage of mite parasitism (assessed by flock indexing) was very high in the initial stages of mite expansion. Unmitigated infestations overall reduced egg production (2.1-4.0%), individual egg weights (0.5-2.2%), and feed conversion efficiency (5.7%), causing a profit reduction of $0.07-0.10 per hen for a 10-week period. Asynchronous infestation patterns among pesticide-treated hens may have contributed to a lack of apparent flock-level economic effects later in the production cycle. Individual egg weights differed with mite loads periodically, but could be either

Associations between PBDEs exposure from house dust and human semen quality at an e-waste areas in South China-A pilot study.

PubMed

Yu, Yun-Jiang; Lin, Bi-Gui; Liang, Wei-Bo; Li, Liang-Zhong; Hong, Yu-de; Chen, Xi-Chao; Xu, Xing-Yu; Xiang, Ming-Deng; Huang, Shan

2018-05-01

Previous studies have confirmed that house dust is one of the main sources of polybrominated diphenyl ethers (PBDEs) exposure, and also indicated that PBDEs might affect human semen quality. The aim of this study was to explore the association between PBDEs concentration in house dust and the semen quality of male resident. Results showed that the semen qualities of the residents living around the e-waste dismantling workshops for a long time (3-17years) at the e-waste areas in South China significantly decreased, and the DNA damage of sperms were aggravated. The adjusted correlation analysed by multiple linear regression model showed that the sperm concentration and count both had negative correlation with BDE47 level in semen (β = -0.295, 95%CI: -0.553∼-0.036; β = -0.400, 95%CI: -0.708∼-0.092, respectively). In addition, the sperm progressive motility [(A+B)%] and sperm viability both had negative correlation with BDE100 level in dust (β = -0.360, 95%CI: -0.680∼-0.040; β = -0.114, 95% CI: -0.203∼-0.025, respectively). And there were significant linear positive correlation between PBDE congener (e.g. BDE28, 47, 153) concentrations in dust and in paired semen samples (r s  = 0.367-0.547, p < 0.05). This study suggested that exposure to PBDEs from house dust might have adverse effects on human semen quality. But the results need to be confirmed in further studies with a large-scale sampling, and find out more direct and convincing evidence. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of high and low temperatures on development time and mortality of house dust mite eggs.

PubMed

Mahakittikun, Vanna; Boitano, John Joseph; Ninsanit, Prapakorn; Wangapai, Teerapong; Ralukruedej, Kornraphat

2011-12-01

Hatching of Dermatophagoides pteronyssinus eggs was investigated when exposed to temperatures ranging from -70 to +70°C, at varying degrees of humidity (dry and wet heat, direct sunlight) and lengths of time (seven intervals, ranging from 0.5 to 5 h). Exposure to cold was induced using a domestic refrigerator at 4°C, its freezing compartment at -10°C and a deep freezer at -20, -40 and -70°C. For each time interval, there were three slides containing 30 eggs per slide, except for sunlight (five sets of slides). After treatment, all experimental groups were kept on an open work bench for 15 days of observation at ambient room temperature (ca. 22°C) and ca. 75% relative humidity. Control groups with 10 eggs per slide, in triplicate, followed a similar protocol. An egg was considered hatched if an emerging larva was detected from a cracked shell. Results indicated that at 40°C for both dry and wet heat, approximately 80% of all eggs survived. At direct sunlight and dry heat at 50°C, the thermal death point (TDP) occurred at 3 and 5 h, respectively. At 60 and 70°C both wet and dry heat, TDP occurred almost instantaneously. Under cold conditions, only the deep freezer at -70°C was effective in preventing hatching. It may be concluded that exposure to direct sunlight for 3 h, dry/wet heat of 60 and 70°C for a minimum of 30 min, and -70°C prevent egg hatching. This study may have relevance for mite control procedures.

Use of fluorinated polybrominated diphenyl ethers and simplified cleanup for the analysis of polybrominated diphenyl ethers in house dust

EPA Science Inventory

A simple, cost-effective method is described for the analysis of polybrominated diphenyl ethers (PBDEs) in house dust using pressurized fluid extraction, cleanup with modified silica solid phase extraction tubes, and fluorinated internal standards. There are 14 PBDE congeners inc...

Household characteristics and allergen and endotoxin levels in Aleppo, Syrian Arab Republic.

PubMed

Al Ali, W; Custovic, A; Simpson, A; Khoury, A; Woodcock, A

2010-07-01

Few data are available from Eastern Mediterranean countries about levels of domestic allergens and endotoxins. Dust samples were collected from mattresses and floors of 457 homes in the Syrian city of Aleppo and analysed for antigens and endotoxins. The most important predictors for detectable levels of house-dust mite allergen Der p 1 were Arabic-style houses (OR 3.21) and newer houses (OR 1.56). In homes without cats, rubber mattresses were associated with detectable cat allergen Fel d 1 in mattress dust (OR 1.6). Cockroach allergen Bla g 2 was significantly more likely to be detected in houses over 20 years old than newer houses. Endotoxin levels were significantly higher in wool/cotton mattresses and older houses.

Coal-Tar-Based Parking Lot Sealcoat: An Unrecognized Source of PAH to Settled House Dust

PubMed Central

2010-01-01

Despite much speculation, the principal factors controlling concentrations of polycyclic aromatic hydrocarbons (PAH) in settled house dust (SHD) have not yet been identified. In response to recent reports that dust from pavement with coal-tar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT). The median concentration of total PAH (T-PAH) in dust from CT parking lots (4760 μg/g, n = 11) was 530 times higher than that from parking lots with other pavement surface types (asphalt-based sealcoat, unsealed asphalt, concrete [median 9.0 μg/g, n = 12]). T-PAH in SHD from apartments with CT parking lots (median 129 μg/g) was 25 times higher than that in SHD from apartments with parking lots with other pavement surface types (median 5.1 μg/g). Presence or absence of CT on a parking lot explained 48% of the variance in log-transformed T-PAH in SHD. Urban land-use intensity near the residence also had a significant but weaker relation to T-PAH. No other variables tested, including carpeting, frequency of vacuuming, and indoor burning, were significant. PMID:20063893

Coal-tar-based parking lot sealcoat: An unrecognized source of PAH to settled house dust

USGS Publications Warehouse

Mahler, B.J.; Van Metre, P.C.; Wilson, J.T.; Musgrove, M.; Burbank, T.L.; Ennis, T.E.; Bashara, T.J.

2010-01-01

Despite much speculation, the principal factors controlling concentrations of polycyclic aromatic hydrocarbons (PAH) in settled house dust (SHD) have not yet been identified. In response to recent reports that dust from pavement with coaltar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT). The median concentration of total PAH (T-PAH) in dust from CT parking lots (4760 ??g/g, n = 11) was 530 times higher than that from parking lots with other pavement surface types (asphalt-based sealcoat, unsealed asphalt, concrete [median 9.0 ??g/g, n = 12]). T-PAH in SHD from apartments with CT parking lots (median 129 ??g/g) was 25 times higher than that in SHD from apartments with parking lots with other pavement surface types (median 5.1 ??g/g). Presence or absence of CT on a parking lot explained 48% of the variance in log-transformed T-PAH in SHD. Urban land-use intensity near the residence also had a significant but weaker relation to T-PAH. No other variables tested, including carpeting, frequency of vacuuming, and indoor burning, were significant. ?? 2010 American Chemical Society.

The presence of quill mites (Gabucinia bicaudata) and lice (Struthiolipeurus struthionis) in ostrich wing feathers.

PubMed

Cooper, R G; El Doumani, H A A

2006-03-01

Quill mites (Gabucinia bicaudata) and lice (Struthiolipeurus struthionis) may infest ostrich feathers, resulting in skin damage, pruritus and excessive feather preening and loss. Four different feather types (prime white, femina extra wide, femina class 1, and femina short; n = 10) were collected. The quill mites and lice were removed with fine forceps, studied using a photographic optical microscope and counted microscopically at x 100 magnification following collection by sedimentation. They were placed in separate Petri dishes containing lactophenol solution and examined (x40 magnification). Anatomical features are described. The density of quill mites in all feather types of both wings was higher than that of the lice. There was no significant difference between the counts of both arthropods on the left wing and the right wing, respectively, except for the femina class 1 quill mites (P = 0.01). The femina extra wide feathers were a preferred habitat in both wings. Large standard deviations (quill mites left wing: 73 +/- 8; quill mites right wing: 69 +/- 7) suggested variations in the degree of migration between feather shafts or as a response to escape preening. It is recommended that ostriches be treated with an oral preparation of Ivermectin administered per os at a dosage rate of 0.2 mg/kg at 30-day intervals for quill mites, and with a 1-5 % Malathion dust at 14-day intervals for lice.

Evaluating the Bioaccessibility of Flame Retardants in House Dust Using an In Vitro Tenax Bead-Assisted Sorptive Physiologically Based Method

PubMed Central

2015-01-01

Exposure to house dust is a significant source of exposure to flame retardant chemicals (FRs), particularly in the US. Given the high exposure there is a need to understand the bioaccessibility of FRs from dust. In this study, Tenax beads (TA) encapsulated within a stainless steel insert were used as an adsorption sink to estimate the dynamic absorption of a suite of FRs commonly detected in indoor dust samples (n = 17), and from a few polyurethane foam samples for comparison. Organophosphate flame retardants (OPFRs) had the highest estimated bioaccessibility (∼80%) compared to brominated compounds (e.g., PBDEs), and values generally decreased with increasing Log Kow, with <30% bioaccessibility measured for BDE209. These measurements were in very close agreement with reported PBDE bioavailability measures from an in vivo rat exposure study using indoor dust. The bioaccessibility of very hydrophobic FRs (Log Kow > 6) in foam was much less than that in house dust, and increasing bioaccessibility was observed with decreasing particle size. In addition, we examined the stability of more labile FRs containing ester groups (e.g., OPFRs and 2-ethylhexyl-tetrabromo-benzoate (EH-TBB)) in a mock-digestive fluid matrix. No significant changes in the OPFR concentrations were observed in this fluid; however, EH-TBB was found to readily hydrolyze to tetrabromobenzoic acid (TBBA) in the intestinal fluid in the presence of lipases. In conclusion, our study demonstrates that the bioaccessibility and stability of FRs following ingestion varies by chemical and sample matrix and thus should be considered in exposure assessments. PMID:25330458

Pesticides in house dust from urban and farmworker households in California: an observational measurement study

PubMed Central

2011-01-01

Background Studies report that residential use of pesticides in low-income homes is common because of poor housing conditions and pest infestations; however, exposure data on contemporary-use pesticides in low-income households is limited. We conducted a study in low-income homes from urban and agricultural communities to: characterize and compare house dust levels of agricultural and residential-use pesticides; evaluate the correlation of pesticide concentrations in samples collected several days apart; examine whether concentrations of pesticides phased-out for residential uses, but still used in agriculture (i.e., chlorpyrifos and diazinon) have declined in homes in the agricultural community; and estimate resident children's pesticide exposures via inadvertent dust ingestion. Methods In 2006, we collected up to two dust samples 5-8 days apart from each of 13 urban homes in Oakland, California and 15 farmworker homes in Salinas, California, an agricultural community (54 samples total). We measured 22 insecticides including organophosphates (chlorpyrifos, diazinon, diazinon-oxon, malathion, methidathion, methyl parathion, phorate, and tetrachlorvinphos) and pyrethroids (allethrin-two isomers, bifenthrin, cypermethrin-four isomers, deltamethrin, esfenvalerate, imiprothrin, permethrin-two isomers, prallethrin, and sumithrin), one phthalate herbicide (chlorthal-dimethyl), one dicarboximide fungicide (iprodione), and one pesticide synergist (piperonyl butoxide). Results More than half of the households reported applying pesticides indoors. Analytes frequently detected in both locations included chlorpyrifos, diazinon, permethrin, allethrin, cypermethrin, and piperonyl butoxide; no differences in concentrations or loadings were observed between locations for these analytes. Chlorthal-dimethyl was detected solely in farmworker homes, suggesting contamination due to regional agricultural use. Concentrations in samples collected 5-8 days apart in the same home were

A double-blind randomized placebo-controlled trial with short-term beta-glucuronidase therapy in children with chronic rhinoconjunctivitis and/or asthma due to dust mite allergy.

PubMed

Galli, E; Bassi, M S; Mora, E; Martelli, M; Gianni, S; Auricchio, G; Arabito, E; Rossi, P

2006-01-01

Enzyme potentiated desensitization, in which beta-glucuronidase (BG) is administered with low doses of mixed allergens, was proposed in the 1970s for specific immunotherapy. The BG currently commercially available in a purified and standardized preparation devoid of any allergen has been suggested as a regulator in the allergic immune response, acting on the cytokine-network of type 2 helper T cells. A double-blind trial with a single-dose of BG proved effective in preventing symptoms in adult patients with rhinoconjunctivitis due to grass pollens. The aim of this randomized double-blind placebo-controlled trial was to confirm the safety and effectiveness of double-dose intradermal BG immunotherapy in preventing symptoms in children suffering from chronic rhinoconjunctivitis and/or asthma due to dust mite. We randomized 125 children with dust-mite related chronic rhinoconjunctivitis and/or asthma to the BG treated group (67) or the placebo group (58). All patients were screened before treatment (TO), at BG or placebo administration (T1 and T3), and at 3 and 9 months after T1 (T2 and T4). Drug intake and bronchial, nasal and ocular symptoms were recorded in a diary. Patients in both groups completed the study and BG treatment was well tolerated without side effects. Significant differences in symptoms were observed, in particular for conjunctivitis (P= .008). The total drug intake for allergic symptoms was significantly lower in the treated group than in the placebo group (P<. 01). BG immunotherapy is efficacious, safe, and well tolerated in allergic children. Moreover, good compliance with the administration of 2 doses per year and the lack of significant side effects makes the benefit/risk ratio of this treatment particularly favorable.

Mite and pet allergen levels in homes of children born to allergic and nonallergic parents: the PIAMA study.

PubMed

van Strien, Rob T; Koopman, Laurens P; Kerkhof, Marjan; Spithoven, Jack; de Jongste, Johan C; Gerritsen, Jorrit; Neijens, Herman J; Aalberse, Rob C; Smit, Henriette A; Brunekreef, Bert

2002-11-01

The Prevention and Incidence of Asthma and Mite Allergy (PIAMA) study is a birth cohort study that investigates the influence of allergen exposure on the development of allergy and asthma in the first several years of life. The objectives of this study were to investigate the relationship between a family history of allergy and/or asthma and exposure of newborn children to mite and pet allergen and to study the influence of different home and occupant characteristics on mite allergen exposure. Dust was sampled from the child's mattress and the parental mattress at 3 months after birth of the index child and analyzed for mite and pet allergens. Subjects were divided in groups according to history of asthma and allergy in their parents, and allergen exposure was studied in the different groups. Cat allergen exposure was significantly lower on parental mattresses in families with allergic mothers, but dog allergen exposure was not different. Mite allergen exposure was lower on parental mattresses in families with allergic mothers. Use of mite allergen-impermeable mattress covers reduced mite allergen exposure. Some other characteristics such as age of home and mattress were also found to influence mite allergen exposure. Parental mattresses in homes of allergic mothers had lower cat and mite (but not dog) allergen loadings than mattresses in homes of nonallergic parents. Paternal (as opposed to maternal) allergy seemed to have little influence.

Indoor allergens, environmental avoidance, and allergic respiratory disease.

PubMed

Bush, Robert K

2008-01-01

Indoor allergen exposure to sources such as house-dust mites, pets, fungi, and insects plays a significant role in patients with allergic rhinitis and asthma. The identification of the major allergens has led to methods that can quantitate exposure, e.g., immunoassays for Der p 1 in settled dust samples. Sensitization and the development of allergic respiratory disease result from complex genetic and environmental interactions. New paradigms that examine the role of other environmental factors, including exposure to proteases that can activate eosinophils and initiate Th2 responses, and epigenetics, are being explored. Recommendations for specific environmental allergen avoidance measures are discussed for house-dust mites, cockroaches, animal dander, and fungi. Specific measures to reduce indoor allergen exposure when vigorously applied may reduce the risk of sensitization and symptoms of allergic respiratory disease, although further research will be necessary to establish cost-effective approaches.

Simultaneous determination of thirteen organophosphate esters in settled indoor house dust and a comparison between two sampling techniques.

PubMed

Fan, Xinghua; Kubwabo, Cariton; Rasmussen, Pat E; Wu, Fang

2014-09-01

An analytical method for the simultaneous determination of 13 organophosphate esters (OPEs) in house dust was developed. The method is based on solvent extraction by sonication, sample cleanup by solid phase extraction (SPE), and analysis by gas chromatography-positive chemical ionization-tandem mass spectrometry (GC/PCI-MS/MS). Method detection limits (MDLs) ranged from 0.03 to 0.43 μg/g and recoveries from 60% to 118%. The inter- and intra-day variations ranged from 3% to 23%. The method was applied to dust samples collected using two vacuum sampling techniques from 134 urban Canadian homes: a sample of fresh or "active" dust (FD) collected by technicians and a composite sample taken from the household vacuum cleaner (HD). Results show that the two sampling methods (i.e., FD vs HD) provided comparable results. Tributoxyethyl phosphate (TBEP), triphenyl phosphate (TPhP), tris(chloropropyl) phosphate (TCPP), tri(2-chloroethyl) phosphate (TCEP), tris(dichloro-isopropyl) phosphate (TDCPP), tricresyl phosphate (TCrP), and tri-n-butyl phosphate (TnBP) were detected in the majority of samples. The most predominant OPE was TBEP, with median concentrations of 31.9 μg/g and 22.8 μg/g in FD and HD samples, respectively, 1 to 2 orders of magnitude higher than other OPEs. The method was also applied to the analysis of OPEs in the National Institute of Standards and Technology (NIST) standard reference material (NIST SRM 2585, organic contaminants in house dust). The results from SRM 2585 may contribute to the certification of OPE concentration values in this SRM. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

The influence of a central vacuum system on quality life in patients with house dust-associated allergic rhinitis.

PubMed

Naguwa, S M; Gershwin, M E

2001-01-01

Indoor pollution is one of the most common problems addressed by allergists and troublesome for their patients. Although a large variety of products are available for removing such pollutants, including house dust, there is a relative paucity of data on the effectiveness of such devices. In many cases, central vacuum systems are recommended, particularly in new homes. To specifically address the question of whether a central vacuum system produces an improvement in the well characterized domains of Juniper Rhinoconjunctivitis Quality of Life Questionnaire, we selected 25 individuals with a history of documented type I hypersensitivity to house dust. Each of these individuals used either a Beam Central Vacuum System or their own conventional vacuum for a period of 3 months. At the end of this period, the individual switched over to the opposite limb of the study for 3 additional months. Interestingly, in all seven domains of the evaluation, including activity, sleep, nonnasal symptoms, practical problems, nasal symptoms, eye symptoms and emotions, use of the central vacuum proved to be superior.

Characterization of Erysipelothrix rhusiopathiae isolates from laying hens and poultry red mites (Dermanyssus gallinae) from an outbreak of erysipelas.

PubMed

Eriksson, Helena; Brännström, Sara; Skarin, Hanna; Chirico, Jan

2010-12-01

Infection with the zoonotic bacterium Erysipelothrix rhusiopathiae causes severe disease outbreaks (erysipelas) in poultry flocks. As this bacterium has been isolated from the poultry red mite (Dermanyssus gallinae), this parasite has been suggested as a possible means of transmission of E. rhusiopathiae on and between poultry farms. To further elucidate the capacity of the mite as a reservoir, we analysed and compared 56 bacterial isolates from laying hens and nine isolates from mites by pulsed-field gel electrophoresis (PFGE), using the restriction enzyme SmaI. The isolates originated from one outbreak in a laying hen flock housed in an indoor litter-based aviary system. Except for two isolates, a homogeneous banding pattern was obtained from all isolates analysed, suggesting that a single strain was the cause of the outbreak. Another finding was that isolates from individual hens could exhibit slightly different PFGE patterns. Mites collected from the same house at the end of the production period of the following flock were negative for the presence of E. rhusiopathiae. An increasing number of erysipelas outbreaks as well as escalating problems with D. gallinae are expected in other European countries related to the forthcoming changes in housing systems for laying hens. Consequently, further studies are needed to investigate the importance of erysipelas in poultry and the importance of D. gallinae in the transmission of E. rhusiopathiae.

Allergic risks of consuming edible insects: A systematic review.

PubMed

Ribeiro, José Carlos; Cunha, Luís Miguel; Sousa-Pinto, Bernardo; Fonseca, João

2018-01-01

The expected future demand for food and animal-derived protein will require environment-friendly novel food sources with high nutritional value. Insects may be one of such novel food sources. However, there needs to be an assessment of the risks associated with their consumption, including allergic risks. Therefore, we performed a systematic review aiming to analyse current data available regarding the allergic risks of consuming insects. We reviewed all reported cases of food allergy to insects, and studied the possibility of cross-reactivity and co-sensitisation between edible insects, crustaceans and house dust mites. We analysed a total of 25 articles - eight assessing the cross-reactivity/co-sensitisation between edible insects, crustaceans and house dust mites; three characterizing allergens in edible insects and 14 case reports, describing case series or prevalence studies of food allergy caused by insects. Cross-reactivity/co-sensitisation between edible insects and crustaceans seems to be clinically relevant, while it is still unknown if co-sensitisation between house dust mites and edible insects can lead to a food allergy. Additionally, more information is also needed about the molecular mechanisms underlying food allergy to insects, although current data suggest that an important role is played by arthropod pan-allergens such as tropomyosin or arginine kinase. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Skin test hypersensitivity for childhood asthma in Istanbul during a period of 16 years.

PubMed

Akcakaya, N; Cokugras, H; Camcioglu, Y; Ozdemir, M

2005-01-01

For diagnosis of allergic disorders, besides history and physical examination, many in vivo and in vitro laboratory tests are used. Skin prick test (SPT) is an easily performed and valuable test in children. Our aim was to evaluate the SPT results of asthmatic children according to age and gender, in Istanbul and its neighborhood, followed for a period of 16 years. Consecutive 5080 asthmatic children, aged 1 to 18 years, admitted to Pediatric Allergy Policlinics of Istanbul University Cerrahpasa Medicine Faculty from 1987 to 2003, were screened retrospectively for 10 frequently exposed allergens. 3086 cases (61 %) had SPT reactivity for one and/or for multiple allergens; the SPT reactivity percentages of the exposed allergens was 50 % (2554 cases) for house dust mites DP, 49 % (2462 cases) for house dust mites DF, 15 % (784 cases) for cat dander, 10 % (525 cases) for dog dander, 4 % (228 cases) for lamb wool, 10 % (504 cases) for wheat, 3 % (162 cases) for egg white, 6 % (345 cases) for hazelnut pollen, 6 % (318 cases) for Candida Albicans, 6 % (326 cases) for Aspergillus Fumigatus. While house dust mites were determined as the predominant allergen for each age groups in this study, allergy against cat dander was the third important allergen in sequence, as cat is a domestic pet which is frequently kept at home in Turkey.

PCR Testing of a Ventilated Caging System to Detect Murine Fur Mites

PubMed Central

Jensen, Eric S; Allen, Kenneth P; Henderson, Kenneth S; Szabo, Aniko; Thulin, Joseph D

2013-01-01

Rodents housed in microisolation caging are commonly monitored for infectious agents by the use of soiled bedding sentinels. This strategy relies on the successful transmission of rodent pathogens from the index rodents via soiled bedding to sentinel cages and the subsequent infection or colonization of sentinel rodents. When the prevalence of a pathogen is low or the target agent is not readily transmitted by soiled bedding, alternative testing methodologies should be used. Given the continued prevalence of institutions self-reporting murine fur mites and with the advent of a new sensitive and specific PCR assay for mites, we sought to determine whether the exhaust system of an individual ventilated caging (IVC) system could be used for monitoring the rack's rodent population for mites rather than relying on the responses of sentinels. We deployed single cages of mice (Mus musculus) that were known to be infested with either Radfordia affinis or Myobia musculi on a 70-cage rack, sampled the horizontal exhaust manifolds weekly, and used the new PCR assay to test these samples for mite DNA. We detected the presence of fur mites at a 94.1% probability of detection within 4 wk of placement. Therefore, we recommend swabbing and testing the shelf exhaust manifolds of IVC racks rather than relying on soiled-bedding sentinels as an indicator of the mite status of the rodents on that rack. PMID:23562030

Mice housed on coal dust-contaminated sand: A model to evaluate the impacts of coal mining on health

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caballero-Gallardo, Karina, E-mail: kcaballerog@unicartagena.edu.co; Olivero-Verbel, Jesus, E-mail: joliverov@unicartagena.edu.co

Coal dust is the most important air pollutant in coal mining in regards to producing deleterious health effects. It permeates the surrounding environment threatening public health. The aim of this study was to evaluate the toxic effects associated with exposure to sand contaminated with coal dust particles below 38 μm in diameter, obtained from a mineral sample collected in the largest coal mine in South America, La Loma, Cesar, Colombia. Sterilized sand was spiked with coal dust to obtain concentrations ranging from zero to 4% coal dust. To model natural exposure, mice were housed for eight weeks in boxes containingmore » this mixture as bedding after which, they were euthanized and blood and tissue samples were collected. Real time PCR analysis revealed an increase in Cyp1A1 mRNA for living on sand with coal dust concentrations greater than 2% compared to mice living on sand without coal dust. Unexpectedly, for mice on coal dust-polluted sand, Sod1, Scd1 and Nqo1 hepatic mRNA were downregulated. The Comet assay in peripheral blood cells and the micronucleus test in blood smears, showed a significant potential genotoxic effect only at the highest coal dust concentration. Histopathological analysis revealed vascular congestion and peribronchial inflammation in the lungs. A dose–response relationship for the presence of hepatic steatosis, vacuolization and nuclei enlargements was observed in the exposed animals. The data suggest living on a soil polluted with coal dust induces molecular, cellular and histopathological changes in mice. Accordingly, the proposed model can be used to identify deleterious effects of exposure to coal dust deposited in soils that may pose health risks for surrounding wildlife populations. - Highlights: • Mice were exposed to coal dust-contaminated sand. • mRNA Markers for PAH exposure, lipid metabolism and oxidative stress increased. • ALT activity in plasma increased at the highest exposure to coal dust. • Liver tissues of

Assessing the efficacy of immunotherapy with a glutaraldehyde-modified house dust mite extract in children by monitoring changes in clinical parameters and inflammatory markers in exhaled breath.

PubMed

Lozano, Jaime; Cruz, María-Jesús; Piquer, Mónica; Giner, Maria-Teresa; Plaza, Ana María

2014-01-01

The aim of this study was to evaluate the effectiveness of specific immunotherapy (SIT) management with allergoids in children with allergic asthma by monitoring changes in clinical parameters and inflammatory markers in exhaled breath. The study population included 43 patients (24 males) of 6-14 years of age, who had allergic asthma and were sensitized to mites. Twenty-three individuals were treated with subcutaneous SIT (PURETHAL® Mites, HAL Allergy) for 8 months, i.e. the SIT group, and 20 were given medication to treat symptoms only, i.e. the control group. Before treatment and after 4 and 8 months, several clinical parameters, the levels of exhaled nitric oxide and the pH of exhaled breath condensate (EBC) were determined. The SIT group presented with an improvement in asthma classification, a reduction in maintenance drug therapy and improved scores on the quality-of-life questionnaire. These changes were not observed in the control group. Both groups presented significant decreases in EBC pH values at 4 and 8 months after treatment compared to at baseline. However, analysis of the variable 'ratio' showed an increase in the EBC pH values after 8 months of treatment in the SIT group compared with the values at 4 months. SIT with standardized mite extract reduces asthma symptoms in children. A decrease in EBC pH values was observed in both groups, although the SIT group presented a tendency of recovered values after 8 months. Future studies of EBC pH monitoring in the longer term are needed to determine the effectiveness of this marker. © 2014 S. Karger AG, Basel.

Mice housed on coal dust-contaminated sand: A model to evaluate the impacts of coal mining on health.

PubMed

Caballero-Gallardo, Karina; Olivero-Verbel, Jesus

2016-03-01

Coal dust is the most important air pollutant in coal mining in regards to producing deleterious health effects. It permeates the surrounding environment threatening public health. The aim of this study was to evaluate the toxic effects associated with exposure to sand contaminated with coal dust particles below 38 μm in diameter, obtained from a mineral sample collected in the largest coal mine in South America, La Loma, Cesar, Colombia. Sterilized sand was spiked with coal dust to obtain concentrations ranging from zero to 4% coal dust. To model natural exposure, mice were housed for eight weeks in boxes containing this mixture as bedding after which, they were euthanized and blood and tissue samples were collected. Real time PCR analysis revealed an increase in Cyp1A1 mRNA for living on sand with coal dust concentrations greater than 2% compared to mice living on sand without coal dust. Unexpectedly, for mice on coal dust-polluted sand, Sod1, Scd1 and Nqo1 hepatic mRNA were downregulated. The Comet assay in peripheral blood cells and the micronucleus test in blood smears, showed a significant potential genotoxic effect only at the highest coal dust concentration. Histopathological analysis revealed vascular congestion and peribronchial inflammation in the lungs. A dose-response relationship for the presence of hepatic steatosis, vacuolization and nuclei enlargements was observed in the exposed animals. The data suggest living on a soil polluted with coal dust induces molecular, cellular and histopathological changes in mice. Accordingly, the proposed model can be used to identify deleterious effects of exposure to coal dust deposited in soils that may pose health risks for surrounding wildlife populations. Copyright © 2016 Elsevier Inc. All rights reserved.

Concentrations and emission rates of aerial ammonia, nitrous oxide, methane, carbon dioxide, dust and endotoxin in UK broiler and layer houses.

PubMed

Wathes, C M; Holden, M R; Sneath, R W; White, R P; Phillips, V R

1997-03-01

1. A survey of the concentration and emission rates of aerial ammonia, nitrous oxide, methane, carbon dioxide, dust and endotoxin was undertaken in 4 examples each of typical UK broiler, cage and perchery houses over 24 h during winter and summer. 2. Overall the air quality within the poultry houses was unsatisfactory as judged by the dual criteria of farmer health and bird performance. 3. Mean concentrations of ammonia ranged from 12.3 to 24.2 ppm while concentrations of methane and nitrous oxide were close to ambient levels. Mass concentrations of aerial dust ranged from 2 to 10 mg/m3 and 0.3 to 1.2 mg/m3 for inspirable and respirable fractions respectively, while endotoxin concentration was typically about 0.1 microgram/m3 (inspirable fraction). 4. Emission rates of gaseous ammonia were rapid (9.2 g (NH3)/h per 500 kg live body weight) and uniform across the three types of building, while emissions of methane and nitrous oxide were slow. Rates of dust emission ranged from 0.86 to 8.24 g/h per 500 kg live body weight in the inspirable size fraction.

Using paired soil and house dust samples in an in vitro assay to assess the post ingestion bioaccessibility of sorbed fipronil

EPA Science Inventory

For children, ingestion of soils and house dusts can be an important exposure pathway for regulated organic compounds. Following ingestion, the extent to which compounds desorb and become bioaccessible is a critical determinant of systemic adsorption.We characterized the physicoc...

Relative Contributions of Agricultural Drift, Para-Occupational, and Residential Use Exposure Pathways to House Dust Pesticide Concentrations: Meta-Regression of Published Data

EPA Science Inventory

Background: Increased pesticide concentrations in house dust in agricultural areas have been attributed to several exposure pathways, including agricultural drift, para-occupational, and residential use. Objective: To guide future exposure assessment efforts, we quantified rel...

Seasonal Allergies: Symptoms, Diagnosis, and Treatment | NIH MedlinePlus the Magazine

MedlinePlus

... for example, 6 weeks for ragweed or grass pollen seasons) Treatment Antihistamines Decongestants Nonsteroidal anti-inflammatory medicines ... things that you are allergic to, such as pollen, house dust mites, mold, pet dander, cockroaches Complications ...

Bee Mite ID: Bee-associated mite genera of the world

USDA-ARS?s Scientific Manuscript database

Bee Mite ID contains an interactive key, fact sheets, an image gallery, and abundant supporting information. The interactive key allows you to choose characters to obtain a list of mite genera possibly matching your specimen. Consult fact sheets to find images and information for a particular mite g...

Clinical characteristics of black asthmatic children.

PubMed

Luyt, D K; Davis, G; Dance, M; Simmank, K; Patel, D

1995-10-01

A prospective study of 455 black asthmatic children (277 boys) attending the Baragwanath Hospital asthma clinic was undertaken. A history was obtained by means of a standardised questionnaire and skin tests were performed. Cough was the commonest presenting symptom and upper respiratory tract infections, exercise and cold weather the commonest symptom precipitants. The relative incidences of the other precipitants reflected the environment of the study population. Associated atopic conditions were present in 75.5% of patients and a family background in 22.2%. Other respiratory diagnoses were commonly made, particularly tuberculosis, which was diagnosed in 7.4%. Fewer than one-third had no positive skin reaction. The commonest allergens were grasses, pollen and house-dust mites. The high proportion of house-dust mite sensitivity (44.2%) contradicts beliefs that they are rare at higher altitudes.

Origin and higher-level diversification of acariform mites - evidence from nuclear ribosomal genes, extensive taxon sampling, and secondary structure alignment.

PubMed

Pepato, A R; Klimov, P B

2015-09-02

Acariformes is the most species-rich and morphologically diverse radiation of chelicerate arthropods, known from the oldest terrestrial ecosystems. It is also a key lineage in understanding the evolution of this group, with the most vexing question whether mites, or Acari (Parasitiformes and Acariformes) is monophyletic. Previous molecular studies recovered Acari either as monophyletic or non-monophyletic, albeit with a limited taxon sampling. Similarly, relationships between basal acariform groups (include little-known, deep-soil 'endeostigmatan' mites) and major lineages of Acariformes (Sarcoptiformes, Prostigmata) are virtually unknown. We infer phylogeny of chelicerate arthropods, using a large and representative dataset, comprising all main in- and outgroups (228 taxa). Basal diversity of Acariformes is particularly well sampled. With this dataset, we conduct a series of phylogenetically explicit tests of chelicerate and acariform relationships and present a phylogenetic framework for internal relationships of acariform mites. Our molecular data strongly support a diphyletic Acari, with Acariformes as the sister group to Solifugae (PP =1.0; BP = 100), the so called Poecilophysidea. Among Acariformes, some representatives of the basal group Endeostigmata (mainly deep-soil mites) were recovered as sister-groups to the remaining Acariformes (i. e., Trombidiformes + and most of Sarcoptiformes). Desmonomatan oribatid mites (soil and litter mites) were recovered as the monophyletic sister group of Astigmata (e. g., stored product mites, house dust mites, mange mites, feather and fur mites). Trombidiformes (Sphaerolichida + Prostigmata) is strongly supported (PP =1.0; BP = 98-100). Labidostommatina was inferred as the basal lineage of Prostigmata. Eleutherengona (e. g., spider mites) and Parasitengona (e. g., chiggers, fresh water mites) were recovered as monophyletic. By contrast, Eupodina (e. g., snout mites and relatives) was not. Marine mites (Halacaridae) were

Managing the Sneezing Season | NIH MedlinePlus the Magazine

MedlinePlus

... production of a special class of antibody called immunoglobulin E (IgE). Fast Facts Allergies are reactions of ... culprit allergens are those found indoors, such as pets, house dust mites, cockroaches and mold. Source: American ...

Mite avoidance can reduce air trapping and airway inflammation in allergic asthmatic children.

PubMed

Peroni, D G; Piacentini, G L; Costella, S; Pietrobelli, A; Bodini, A; Loiacono, A; Aralla, R; Boner, A L

2002-06-01

We investigated the effects of prolonged allergen avoidance in 18 house dust mite-sensitized asthmatic children during a prolonged residential period at a high altitude, allergen-free environment. Evaluations of residual volume (RV) and exhaled nitric oxide (eNO) were performed (i) at admission to the residential house in September, (ii) in December after 3 months of stay, (iii) in January after 15 days at home, exposed to allergens, and (iv) in June after 9 months of stay. During the study period RV showed a significant decrease in December (from 117.5 +/- 7.7% to 96.5 +/- 3.2%) (P < 0.02) and a following increase in January (126.2 +/- 17.2%), after allergen re-exposure (P < 0.03). RV decreased again in June at the end of the study period (91.1 +/- 6.0%) (P = 0.001). FEV(1), FEF(25-75) and VC values did not present significant variations. ENO showed a significant decrease in December after 3 months at high altitude (from 21.3 +/- 3.9 p.p.b. to 11.9 +/- 1.7 p.p.b.) (P = 0.03), but no further significant change. No correlation was found between lung volumes and eNO, probably reflecting different aspects of asthma. Results suggest that RV may be more sensitive than other respiratory function parameters in identifying children with air trapping, being influenced significantly as the inflammatory indices by effective allergen avoidance/exposure regimen.

House Dust Endotoxin and Peripheral Leukocyte Counts: Results from Two Large Epidemiologic Studies.

PubMed

Fessler, Michael B; Carnes, Megan U; Salo, Päivi M; Wilkerson, Jesse; Cohn, Richard D; King, Debra; Hoppin, Jane A; Sandler, Dale P; Travlos, Greg; London, Stephanie; Thorne, Peter; Zeldin, Darryl

2017-05-31

The peripheral leukocyte count is a biomarker of inflammation and is associated with human all-cause mortality. Although causes of acute leukocytosis are well-described, chronic environmental determinants of leukocyte number are less well understood. We investigated the relationship between house dust endotoxin concentration and peripheral leukocyte counts in human subjects. The endotoxin–leukocyte relationship was evaluated by linear regression in the National Health and Nutrition Examination Survey (NHANES) 2005–2006 (n=6,254) and the Agricultural Lung Health Study (ALHS; n=1,708). In the ALHS, we tested for a gene [Toll-like Receptor 4 ( TLR4 ), encoding the endotoxin receptor]-by-environment interaction in the endotoxin–leukocyte relationship using regression models with an interaction term. There is a statistically significant, positive association between endotoxin concentration and total leukocyte number [estimated change, 0.186×10 3 /μL (95% CI: 0.070, 0.301×10 3 /μL) per 10-fold change in endotoxin; p=0.004) in the NHANES. Similar positive associations were found for monocytes, lymphocytes, and neutrophils. Stratified analyses revealed possible effect modification by asthma and chronic obstructive pulmonary disease. We observed similar associations in the ALHS. For total leukocytes, there was suggestive evidence in the ALHS of a gene-by-environment interaction for minor allele carrier status at the TLR4 haplotype defined by rs4986790 and rs4986791 (interaction p=0.15). This is, to our knowledge, the first report of an association between house dust endotoxin and leukocyte count in a national survey. The finding was replicated in a farming population. Peripheral leukocyte count may be influenced by residential endotoxin exposure in diverse settings. https://doi.org/10.1289/EHP661.

House Dust Endotoxin and Peripheral Leukocyte Counts: Results from Two Large Epidemiologic Studies

PubMed Central

Carnes, Megan U.; Salo, Päivi M.; Wilkerson, Jesse; Cohn, Richard D.; King, Debra; Hoppin, Jane A.; Sandler, Dale P.; Travlos, Greg; London, Stephanie J.; Thorne, Peter S.; Zeldin, Darryl C.

2017-01-01

Background: The peripheral leukocyte count is a biomarker of inflammation and is associated with human all-cause mortality. Although causes of acute leukocytosis are well-described, chronic environmental determinants of leukocyte number are less well understood. Objectives: We investigated the relationship between house dust endotoxin concentration and peripheral leukocyte counts in human subjects. Methods: The endotoxin–leukocyte relationship was evaluated by linear regression in the National Health and Nutrition Examination Survey (NHANES) 2005–2006 (n=6,254) and the Agricultural Lung Health Study (ALHS; n=1,708). In the ALHS, we tested for a gene [Toll-like Receptor 4 (TLR4), encoding the endotoxin receptor]-by-environment interaction in the endotoxin–leukocyte relationship using regression models with an interaction term. Results: There is a statistically significant, positive association between endotoxin concentration and total leukocyte number [estimated change, 0.186×103/μL (95% CI: 0.070, 0.301×103/μL) per 10-fold change in endotoxin; p=0.004) in the NHANES. Similar positive associations were found for monocytes, lymphocytes, and neutrophils. Stratified analyses revealed possible effect modification by asthma and chronic obstructive pulmonary disease. We observed similar associations in the ALHS. For total leukocytes, there was suggestive evidence in the ALHS of a gene-by-environment interaction for minor allele carrier status at the TLR4 haplotype defined by rs4986790 and rs4986791 (interaction p=0.15). Conclusions: This is, to our knowledge, the first report of an association between house dust endotoxin and leukocyte count in a national survey. The finding was replicated in a farming population. Peripheral leukocyte count may be influenced by residential endotoxin exposure in diverse settings. https://doi.org/10.1289/EHP661 PMID:28599265

Fungi of the house dust in Riyadh, Saudi Arabia.

PubMed

Saad, R R; el-Gindy, A A

1990-01-01

30 species belonging to 18 genera were isolated from floor dust of 30 homes in Riyadh. Out of them 16 species and 10 genera were isolated from dust of air conditioners of the same homes. The most common genera in floor dust were Aspergillus, Penicillium and Cladosporium. Aspergillus repens, A. amstelodami, A. versicolor, A. fumigatus, Penicillium purpurogenum, P. crustosum, Cladosporium cladosporoides and C. herbarum were frequently isolated. The most abundant genera in air conditioner dust were Aspergillus and Penicillium. Aspergillus fumigatus, A. ochraceus, A. terreus, Penicillium oxalicium and P. crustosum were most frequent species.

Structural Mechanisms of Inactivation in Scabies Mite Serine Protease Paralogues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fischer, Katja; Langendorf, Christopher G.; Irving, James A.

2009-08-07

The scabies mite (Sarcoptes scabiei) is a parasite responsible for major morbidity in disadvantaged communities and immuno-compromised patients worldwide. In addition to the physical discomfort caused by the disease, scabies infestations facilitate infection by Streptococcal species via skin lesions, resulting in a high prevalence of rheumatic fever/heart disease in affected communities. The scabies mite produces 33 proteins that are closely related to those in the dust mite group 3 allergen and belong to the S1-like protease family (chymotrypsin-like). However, all but one of these molecules contain mutations in the conserved active-site catalytic triad that are predicted to render them catalyticallymore » inactive. These molecules are thus termed scabies mite inactivated protease paralogues (SMIPPs). The precise function of SMIPPs is unclear; however, it has been suggested that these proteins might function by binding and protecting target substrates from cleavage by host immune proteases, thus preventing the host from mounting an effective immune challenge. In order to begin to understand the structural basis for SMIPP function, we solved the crystal structures of SMIPP-S-I1 and SMIPP-S-D1 at 1.85 {angstrom} and 2.0 {angstrom} resolution, respectively. Both structures adopt the characteristic serine protease fold, albeit with large structural variations over much of the molecule. In both structures, mutations in the catalytic triad together with occlusion of the S1 subsite by a conserved Tyr200 residue is predicted to block substrate ingress. Accordingly, we show that both proteases lack catalytic function. Attempts to restore function (via site-directed mutagenesis of catalytic residues as well as Tyr200) were unsuccessful. Taken together, these data suggest that SMIPPs have lost the ability to bind substrates in a classical 'canonical' fashion, and instead have evolved alternative functions in the lifecycle of the scabies mite.« less

A novel and well tolerated mite allergoid subcutaneous immunotherapy: evidence of clinical and immunologic efficacy

PubMed Central

Roger, Albert; Depreux, Nathalie; Jurgens, Yani; Heath, Matthew D; Garcia, Gloria; Skinner, Murray A

2014-01-01

Allergy to house dust mite is one of the most common causes of allergic rhinitis. A novel tyrosine-adsorbed, modified allergen product, Acarovac Plus, developed for the treatment of perennial mite allergy seeks to address the underlying cause of allergic rhinitis in this instance. One of two dosing regimens may be used, either the Conventional Regimen or the Cluster Regimen. We sought to compare the efficacy and safety of a specific immunotherapy, developed for the treatment of perennial mite allergy, administered under a Conventional and Clustered dosing schedule in patients with persistent allergic rhinitis. Thirty adult patients, between 18 and 65 years old, with allergic rhinitis and/or asthma secondary to hypersensitivity to Dermatophagoides pteronyssinus were administered with either conventional or cluster initial regime, with a final visit one week after the last dose administration. The efficacy to the Conventional and Cluster regimens was measured using a Nasal Challenge Test monitoring clinical symptoms and peak nasal inspiratory flow. Total IgE, serum-specific inmunoglobulins (IgE and IgG4) to Dermatophagoides pteronyssinus and relevant cytokines (IFN-γ, IL-4, IL-5, IL-10 and IL-13) were assessed. A Satisfaction Questionnaire (TSQM) was completed after each patient's final visit. The tolerability of the vaccine was assessed monitoring adverse reactions. No adverse events were recorded in either conventional or cluster regime. The specific Nasal Challenge Test led to a decrease in symptom scores and a significant decrease in mean nasal peak inspiratory flow drop was recorded in both dosing regimen groups. A significant increase in IgG4-specific antibody titres was assessed. No significant changes were observed in concentrations of total IgE, specific IgE or cytokines (IFN-γ, IL-4, IL-5, IL-10 and IL-13). Patients declared themselves most satisfied in relation to “Secondary effects”, with high overall satisfaction in both groups. Cluster and

Associations of phthalate concentrations in floor dust and multi-surface dust with the interior materials in Japanese dwellings.

PubMed

Ait Bamai, Yu; Araki, Atsuko; Kawai, Toshio; Tsuboi, Tazuru; Saito, Ikue; Yoshioka, Eiji; Kanazawa, Ayako; Tajima, Shuji; Shi, Cong; Tamakoshi, Akiko; Kishi, Reiko

2014-01-15

Phthalates are widely used as plasticizers in numerous products. However, there has been some concern about the various effects they may have on human health. Thus, household phthalate levels are an important public health issue. While many studies have assessed phthalate levels in house dust, the association of these levels with building characteristics has scarcely been examined. The present study investigated phthalate levels in house dust samples collected from the living areas of homes, and examined associations between these phthalate levels and the interior materials. Dust was collected from two portions of the living area: floor dust from the entire floor surface, and multi-surface dust from objects more than 35 cm above the floor. The levels of seven phthalates were measured using gas chromatography/mass spectrometry in selective ion monitoring mode. Phthalate levels were higher in multi-surface dust than in floor dust. Among floor dust samples, those from dwellings with compressed wooden flooring had significantly higher levels of di-iso-butyl phthalate compared to those with other floor materials, while polyvinyl chloride (PVC) flooring was associated with higher di-2-ethylhexyl phthalate (DEHP) levels. Among multi-surface dust samples, higher levels of DEHP and di-iso-nonyl phthalate (DINP) were found in samples from homes with PVC wallpaper than without. The number of PVC interior materials was significantly positively correlated with the levels of DEHP and DINP in multi-surface dust. The phthalate levels in multi-surface dust were associated with the interior surface materials, and those in floor dust were directly related to the flooring materials. Our findings show that when using house dust as an exposure assessment, it is very important to note where the samples were collected from. The present report provides useful information about the association between phthalates and dust inside dwellings, which will assist with establishing public health

Bacterial and fungal components in house dust of farm children, Rudolf Steiner school children and reference children--the PARSIFAL Study.

PubMed