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Sample records for dust mite control

  1. House dust mite control measures for asthma

    DEFF Research Database (Denmark)

    Gøtzsche, Peter C.; Johansen, Helle Krogh

    2008-01-01

    antigens in the homes of people with mite-sensitive asthma. SEARCH STRATEGY: PubMed and The Cochrane Library (last searches Nov 2007), reference lists. SELECTION CRITERIA: Randomised trials of mite control measures vs placebo or no treatment in people with asthma known to be sensitive to house dust mites.......07), or in medication usage (standardised mean difference -0.06, 95% CI -0.18 to 0.07). AUTHORS' CONCLUSIONS: Chemical and physical methods aimed at reducing exposure to house dust mite allergens cannot be recommended. It is doubtful whether further studies, similar to the ones in our review, are worthwhile. If other...

  2. Dust Mite Allergy

    Science.gov (United States)

    Dust mite allergy Overview By Mayo Clinic Staff Dust mite allergy is an allergic reaction to tiny bugs that commonly live in house dust. Signs of dust mite allergy include those common to hay fever, such as ...

  3. House dust mite control measures for asthma: systematic review

    DEFF Research Database (Denmark)

    Gøtzsche, Peter C.; Johansen, Helle Krogh

    2008-01-01

    The major allergen in house dust comes from mites. We performed a systematic review of the randomized trials that had assessed the effects of reducing exposure to house dust mite antigens in the homes of people with mite-sensitive asthma, and had compared active interventions with placebo...... improved (relative risk 1.01, 95% CI 0.80-1.27), asthma symptom scores (standardized mean difference -0.04, 95% CI -0.15 to 0.07) or in medication usage (standardized mean difference -0.06, 95% CI -0.18 to 0.07). Chemical and physical methods aimed at reducing exposure to house dust mite allergens cannot...

  4. House dust mites, our intimate associates.

    Science.gov (United States)

    Nadchatram, M

    2005-06-01

    House dust mites have lived in human contact from time immemorial. Human dander or dead skin constitutes the major organic component of the house dust ecosystem. Because the mites feed on dander, dust mites and human association will continue to co-exist as part of our environment. Efficient house-keeping practice is the best form of control to reduce infestation. However, special precautions are important when individuals are susceptible or sensitive to dust mites. House dust mites are responsible for causing asthma, rhinitis and contact dermatitis. The respiratory allergies are caused by the inhalation of dead or live mites, their faecal matter or other byproducts. Immune factors are of paramount importance in the development of dust related or mite induced respiratory diseases. House dust mites were found in some 1,000 samples of dust taken from approximately 330 dwellings in Peninsular Malaysia and Singapore. Mattresses, carpets, corners of a bedroom, and floor beneath the bed are favourable dust mite habitats. The incriminating species based on studies here and elsewhere, as well as many other species of dust mites of unknown etiological importance are widely distributed in Malaysian homes. Density of dust mites in Malaysia and Singapore is greater than in temperate countries. Prevention and control measures with reference to subjects sensitive to dust mite allergies, including chemical control described in studies conducted in Europe and America are discussed. However, a cost free and most practical way to remove mites, their faecal matter and other products is to resort to sunning the bedding and carpets to kill the living mites, and then beaten and brushed to remove the dust and other components.

  5. House dust mite barrier bedding for childhood asthma: randomised placebo controlled trial in primary care [ISRCTN63308372

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    Barnes Greta

    2002-06-01

    Full Text Available Abstract Background The house dust mite is the most important environmental allergen implicated in the aetiology of childhood asthma in the UK. Dust mite barrier bedding is relatively inexpensive, convenient to use, and of proven effectiveness in reducing mattress house dust mite load, but no studies have evaluated its clinical effectiveness in the control of childhood asthma when dispensed in primary care. We therefore aimed to evaluate the effectiveness of house dust mite barrier bedding in children with asthma treated in primary care. Methods Pragmatic, randomised, double-blind, placebo controlled trial conducted in eight family practices in England. Forty-seven children aged 5 to 14 years with confirmed house dust mite sensitive asthma were randomised to receive six months treatment with either house dust mite barrier or placebo bedding. Peak expiratory flow was the main outcome measure of interest; secondary outcome measures included asthma symptom scores and asthma medication usage. Results No difference was noted in mean monthly peak expiratory flow, asthma symptom score, medication usage or asthma consultations, between children who received active bedding and those who received placebo bedding. Conclusions Treating house dust mite sensitive asthmatic children in primary care with house dust mite barrier bedding for six months failed to improve peak expiratory flow. Results strongly suggest that the intervention made no impact upon other clinical features of asthma.

  6. [House dust mite allergy].

    Science.gov (United States)

    Carrard, A; Pichler, C

    2012-04-01

    House dust mites can be found all over the world where human beings live independent from the climate. Proteins from the gastrointestinal tract- almost all known as enzymes - are the allergens which induce chronic allergic diseases. The inhalation of small amounts of allergens on a regular base all night leads to a slow beginning of the disease with chronically stuffed nose and an exercise induced asthma which later on persists. House dust mites grow well in a humid climate - this can be in well isolated dwellings or in the tropical climate - and nourish from human skin dander. Scales are found in mattresses, upholstered furniture and carpets. The clinical picture with slowly aggravating complaints leads quite often to a delayed diagnosis, which is accidently done on the occasion of a wider spectrum of allergy skin testing. The beginning of a medical therapy with topical steroids as nasal spray or inhalation leads to a fast relief of the complaints. Although discussed in extensive controversies in the literature - at least in Switzerland with the cold winter and dry climate - the recommendation of house dust mite avoidance measures is given to patients with good clinical results. The frequent ventilation of the dwelling with cold air in winter time cause a lower indoor humidity. Covering encasings on mattresses, pillow, and duvets reduces the possibility of chronic contact with mite allergens as well as the weekly changing the bed linen. Another option of therapy is the specific immunotherapy with extracts of house dust mites showing good results in children and adults. Using recombinant allergens will show a better quality in diagnostic as well as in therapeutic specific immunotherapy.

  7. A controlled intervention study concerning the effect of intended temperature rise on house dust mite load

    DEFF Research Database (Denmark)

    Sidenius, Kirsten E; Hallas, Thorkil E; Poulsen, Lars K.

    2002-01-01

    In epidemiological studies, increased indoor temperature--producing a lower relative humidity--is associated with low house dust mite (HDM) load. Twenty-eight dwellings were allocated for either intervention (12/15 completed) or control (11/13 completed). In the intervention group, participants...... were asked to increase the bedroom temperature by at least 3 degrees C compared to the self-assessed temperature of the previous winter. Dust samples were repeatedly collected from mattress and floor, and bedroom temperature and relative humidity were recorded hourly throughout one year. Dust...... C). Groups turned out not to be comparable with respect to initial (self-assessed) bedroom temperature (lowest in the intervention group). There was a significant seasonal variation, with doubled Der 1 concentrations in dust collected in July-November compared to January-May samples. No effect...

  8. Mite-control activities of active constituents isolated from Pelargonium graveolens against house dust mites.

    Science.gov (United States)

    Jeon, Ju-Hyun; Kim, Hyung-Wook; Kim, Min-Gi; Lee, Hoi-Seon

    2008-10-01

    The mite-control activities of materials obtained from Pelargonium graveolens oil against Dermatophagoides farinae and D. pteronyssinus were examined using an impregnated fabric disk bioassay and were compared with those shown by commercial benzyl benzoate and N,N-diethylm- toluamide (DEET). Purification of the biologically active constituents from P. graveolens oil was done by silica gel chromatography and high performance liquid chromatography. The structures of the active components were analyzed by EI/MS, (1)H-NMR, (13)C-NMR, (1)H-(13)C COSYNMR, and DEPT-NMR spectra, and were identified as geraniol (C(10)H(18)O, MW 154.25, trans-3,7-dimethyl-2,6- octadien-1-ol) and beta-citronellol (C(10)H(20)O, MW 156.27, 3,7-dimethyl-6-octen-1-ol). Based on the LD50 values, the most toxic compound was geraniol (0.26 microg/cm(2)), followed by beta-citronellol (0.28 microg/cm(2)), benzyl benzoate (10.03 microg/ cm(2)), and DEET (37.12 microg/cm(2)) against D. farinae. In the case of D. pteronyssinus, geraniol (0.28 microg/cm(2)) was the most toxic, followed by beta-citronellol (0.29 microg/cm(2)), benzyl benzoate (9.58 microg/cm(2)), and DEET (18.23 microg/cm(2)). These results suggest that D. farinae and D. pteronyssinus may be controlled more effectively by the application of geraniol and beta-citronellol than benzyl benzoate and DEET. Furthermore, geraniol and beta-citronellol isolated from P. graveolens could be useful for managing populations of D. farinae and D. pteronyssinus.

  9. THE USE OF SUPEROXIDE DISMUTASE IN ACCELERATING SYMPTOM RELIEF IN ASTHMATIC AND HOUSE DUST MITE ALLERGIC CHILDREN RECEIVING HOUSE DUST MITE IMMUNOTHERAPY: DOUBLE BLIND RANDOMIZED CONTROLLED CLINICAL TRIAL

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    Anang Endaryanto

    2015-09-01

    Full Text Available Objective: To evaluate the efficacy of superoxide dismutase (SOD in lung function (FEV1 reversibility and respiratory symptoms (drug scores, symptoms scores in asthmatic and house dust mite allergic children receiving house dust mites immunotherapy. Methods: Forty subjects aged 6–17 years old with asthma, tested positive for house dust mite allergy on skin prick test, and received immunotherapy were enrolled in this study. All subjects completed clinical based assessments and diary-based assessments for drug and symptom scores. Following a four-week baseline assessment, all subjects were randomized to receive SOD or placebo. Respiratory symptoms (drug and symptoms score and FEV1 were evaluated at the end of the 1st, 2nd, 3rd, and 4th weeks after randomization. Drug score, symptoms score, and FEV1 reversibility test results were analyzed using a Paired t test and repeated measure of ANOVA. Results: There was a significant difference in drug scores, symptoms score, and FEV1 reversibility test outcomes between SOD and placebo. SOD group showed a significant decrease in all outcome measures compared to those in placebo group. Conclusions: The use of SOD as antioxidants is effective in accelerating symptom relief for children with asthma and house dust mite allergy receiving house dust mite immunotherapy.

  10. Placebo-controlled trial of house dust mite-impermeable mattress covers - Effect on symptoms in early childhood

    NARCIS (Netherlands)

    Koopman, LP; van Strien, RT; Kerkhof, M; Wijga, A; Smit, HA; de Jongste, JC; Gerritsen, J; Aalberse, RC; Brunekreef, B; Neijens, HJ

    2002-01-01

    We investigated the effect of house dust mite (HDM)-allergen avoidance on the development of respiratory Symptoms, atopic dermatitis, and atopic sensitization by performing a double blind, placebo-controlled trial. In total, 1,282 allergic pregnant women were selected (416 received HDM allergen-impe

  11. House Dust Mite Respiratory Allergy

    DEFF Research Database (Denmark)

    Calderón, Moisés A; Kleine-Tebbe, Jörg; Linneberg, Allan

    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 e...

  12. Recombinant house dust mite allergens

    OpenAIRE

    2013-01-01

    House dust mites (HDM) are a globally important source of allergen responsible for the sensitization of more than 50% of allergic patients. Specific immunotherapy with HDM extracts is effective but allergen extracts cannot be fully standardized and severe side-effects can occur during the protracted course of treatment. The introduction of molecular biological techniques into allergy research allowed the indentification of more than 20 groups of HDM allergens. Recombinant HDM allergens can be...

  13. House dust mite allergen avoidance and self-management in allergic patients with asthma: randomised controlled trial.

    NARCIS (Netherlands)

    Vries, M.P. de; Bemt, L. van den; Aretz, K.; Thoonen, B.P.A.; Muris, J.W.M.; Kester, A.D.; Cloosterman, S.G.M.; Schayck, C.P. van

    2007-01-01

    BACKGROUND: The efficacy of bed covers that are impermeable to house dust mites has been disputed. AIM: The aim of the present study was to investigate whether the combination of 'house dust mite impermeable' covers and a self-management plan, based on peak flow values and symptoms, leads to reduced

  14. THE MAIN CULPRIT IN ALLERGIC RHINITIS - HOUSE DUST OR HOUSE DUST MITE

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    Abhey

    2015-10-01

    Full Text Available Allergic rhinitis especially perennial type makes life miserable for the patient. House dust mite is one of the major players causing it. This study is to compare the allergen i n city of house dust mite versus house dust and evaluate any cross - allergenicity between them. STUDY DESIGN: Prospective study in a tertiary referral hospital. MATERIALS & METHODS: Forty patients of allergic rhinitis and well matched controls were subjected to intradermal skin tests to house dust and house dust mite allergen. The skin tests were graded as per standard norms and the responses matched after correlating with different parameters. Statistical analysis was done and the results evaluated. RESULTS: House dust mite was the main allergen, as compared to house dust, responsible for causing allergic rhinitis. The allergen reactivity potential of house dust mite was significantly more as compared to house dust. And, as such there was no statistically significant cross - allergenicity between the two groups. CONCLUSION: House dust mite rather than house dust is the main culprit in causing allergic rhinitis. Hence, precautionary and preventive measures to control the exposure to house dust mite can be undertaken

  15. [House dust mites and their allergens].

    Science.gov (United States)

    Bessot, J-C; Pauli, G

    2011-02-01

    The taxonomy, anatomy, life cycle and ecology of Pyroglyphidae mites and storage mites (Acaridae, Glycyphagidae, B. tropicalis) are described. Pyroglyphidae and storage mites have similar morphologies: they are octopods, with characteristic gnathosoma and sensory hairs. Salivary glands and the mid gut produce most of the allergens excreted, which are enzymatic proteins. Biological cycles and development are similar, although fecundity is superior in storage mites compared to the Pyroglyphides. Relative humidity is the main parameter, which regulates mite development, with a higher degree of temperature and humidity required for storage mites. Bedding is the ecological niche of Pyroglyphidae, which feed on human skin. Moulds and food products are the storage mite biotope from which they spread in the dwelling. Initially considered as rural mites, storage mites are also present in urban dwellings. B. tropicalis, in tropical regions is a true domestic mite. Because of this, it is justified to denominate Pyroglyphidae "house dust mites" and storage mites "domestic mites". In addition to the respiratory allergic symptoms, the storage mites can also cause occupational contact dermatoses.

  16. Allergy to house dust mites and asthma.

    Science.gov (United States)

    Milián, Evelyn; Díaz, Ana María

    2004-03-01

    House dust mites have been shown to be important sources of indoor allergens associated with asthma and other allergic conditions. Asthma is a chronic respiratory disease that affects millions of people worldwide, and numerous scientific studies have shown that the prevalence of asthma is increasing. The most common dust mite species around the world include Dermatophagoides pteronyssinus (Dp), Dermatophagoides farinae (Df), Euroglyphus maynei (Em) and Blomia tropicalis (Bt). Over the past three decades, many important allergens from these species have been identified and characterized at the molecular level. The biological function of several house dust mite allergens has been elucidated, with many of them showing enzymatic activity. However, Bt allergens remain the least studied, even though this mite is very common in tropical and subtropical regions of the world, including Puerto Rico. Therefore, it is very important to include Bt in diagnostic and therapeutic strategies for house dust mite induced allergy and asthma, particularly in areas where Bt exposure and sensitization is high. Recombinant DNA technology, as well as other molecular biology and immunological techniques, have played a fundamental role in advances towards a better understanding of the biology of house dust mites and their role in allergic diseases. This kind of study also contributes to the understanding of the complex immunologic mechanisms involved in allergic reactions. The development of effective diagnostic and therapeutic approaches depends on the continuity of research of house dust mite allergens. The objectives of this review are to describe the most important aspects of house dust mite allergy and to acquaint the scientific community with the latest findings pertaining to house dust mite allergens, particularly those derived from Bt.

  17. Effect of Activated Charcoal Fibers on the Survival of the House Dust Mite, Dermatophagoides pteronyssinus: A Pilot Study.

    Science.gov (United States)

    Nam, Hae-Seon; Lee, Sun-Hwa; Choi, Young-Jin; Park, Joon-Soo; Cho, Moon-Kyun; Lee, Sang-Han; Crane, Julian; Siebers, Robert

    2012-01-01

    House dust mites produce potent allergens that exacerbate asthma in sensitized patients, whom are recommended to practice allergen avoidance within their home environment. We tested the effect of activated charcoal impregnated fibers on house dust mite survival. One hundred live adult house dust mites (Dermatophagoides pteronyssinus) were added to eight culture dishes preequilibrated at room temperature (n = 4) and 70% humidity (n = 4) containing house dust mite food and active charcoal fibers. At 10 minute intervals, live and dead house dust mites were counted. All house dust mites instantly attached to the activated charcoal fibers and started to shrink almost immediately. There were no live house dust mites present as early as 40 minutes in some dishes while after 190 minutes all house dust mites were dead. In conclusion, activated charcoal fibers, if incorporated into bedding items, have the potential to control house dust mites in the indoor environment.

  18. Mite antigen and allergen contents of house dust samples.

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    Ishii,Akira

    1988-02-01

    Full Text Available The house dust mite (Dermatophagoides pteronyssinus antigen and allergen contents were measured by enzyme-linked immunosorbent assay (ELISA with enzyme-labelled anti-human IgE and anti-mite rabbit IgG antibodies. Antigen content was high in dust samples from homes of patients with allergy but not in samples from homes of patients with Kawasaki disease or of normal control subjects. Allergen content was high in dust samples from homes of Kawasaki disease patients. However, the values overlapped, and we considered these differences to be of little ecological significance, although the assay method itself is useful.

  19. Pheromonal Communication in the European House Dust Mite, Dermatophagoides pteronyssinus

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    Johannes L.M. Steidle

    2014-08-01

    Full Text Available Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897, the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME revealed that nerol, neryl formate, pentadecane, (6Z,9Z-6,9-heptadecadiene, and (Z-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies.

  20. Activated charcoal suppresses breeding of the house dust mite, Dermatophagoides pteronyssinus, in culture.

    Science.gov (United States)

    Nam, Hae-Seon; Siebers, Robert; Lee, Sun-Hwa; Kim, Sung-Ho; Lee, Sang-Han; Crane, Julian

    2007-04-01

    House dust mite sensitized asthmatics are advised to practice allergen avoidance. Charcoal pillows are used in Korea with unsubstantiated claims regarding their efficacy in alleviating asthma symptoms. We tested the effects of activated charcoal on breeding of house dust mites in culture. Twenty live adult house dust mites (Dermatophagoides pteronyssinus) were inoculated, 10 replicates, on culture media containing 0%, 1%, 3%, 5%, 10%, and 20% activated charcoal and incubated at 25 degrees C and a relative humidity of 75%. After four weeks, the mean numbers of live house dust mites were 286, 176, 46, 16, 7, and 0 for the 0%, 1%, 3%, 5%, 10%, and 20% charcoal-containing culture media, respectively. Thus, activated charcoal suppresses breeding of house dust mites and offers a new promising method for house dust mite control.

  1. Respiratory allergy caused by house dust mites

    DEFF Research Database (Denmark)

    Calderón, Moisés A; Linneberg, Allan; Kleine-Tebbe, Jörg

    2015-01-01

    The house dust mite (HDM) is a major perennial allergen source and a significant cause of allergic rhinitis and allergic asthma. However, awareness of the condition remains generally low. This review assesses the links between exposure to HDM, development of the allergic response, and pathologic ...

  2. Laboratory evaluation of the effect of inert dust formulations on the poultry red mite, Dermanyssus gallinae

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Steenberg, Tove

    In the EU-project SAFEHOUSE one objective is to develop alternative control methods against poultry red mites based on a combination of inert dusts and mite-pathogenic fungal isolates. Both components have some pathogenicity to the mites. However, the question is whether a combination of the two ...

  3. Diversity of House Dust Mite Species in Xishuangbanna Dai, a Tropical Rainforest Region in Southwest China

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    Jing-Miao Yu

    2015-01-01

    Full Text Available Purpose. To survey the species diversity of home dust mites (HDM in Xishuangbanna, a tropical rainforest region in Southwest China. Methods. From August 2010 to January 2011, mite-allergic patients and healthy controls were invited to participate. Dust samples from the patients’ homes were collected, and mites in the samples were isolated. Permanent slides were prepared for morphologically based species determination. Results. In total, 6316 mite specimens of morphologically identifiable species were found in 233 dust samples taken from 41 homes. The result shows that the mite family of Pyroglyphidae occupied the highest percentage of the total amount of mites collected, followed by Cheyletidae family. The most common adult Pyroglyphidae mites were Dermatophagoides (D. farinae, D. pteronyssinus, and D. siboney. The most common mites found from other families were Blomia tropicalis, Tyrophagus putrescentiae, and Aleuroglyphus ovatus. Four main allergenic dust mite species D. farinae, D. pteronyssinus, D. siboney, and Blomia tropicalis were found to be coinhabiting in 6/41 homes. Conclusion. The HDM population in homes in Xishuangbanna, a tropical rainforest region in Southwest China, has its own characteristics. It has rich dust mite species and the dust mite densities do not show significant variation across seasons.

  4. House dust mites in Brazil - an annotated bibliography

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    Binotti Raquel S

    2001-01-01

    Full Text Available House dust mites have been reported to be the most important allergen in human dwellings. Several articles had already shown the presence of different mite species at homes in Brazil, being Pyroglyphidae, Glycyphagidae and Cheyletidae the most important families found. This paper is an annotated bibliography that will lead to a better knowledge of house dust mite fauna in Brazil.

  5. Dust mites in a routine clinical stool sample

    Institute of Scientific and Technical Information of China (English)

    Bushra Zia; Hassaan Bin Aftab; Mohammad Faizan Zahid; Joveria Farooqi; Feroze Uddin; Mohammad Asim Beg

    2014-01-01

    We report a case of dust mite carriage in a 56-year-old gentleman. Dust mites eggs and larvae were found in a stool sample which was taken for a routine clinical examination. He was completely asymptomatic with no history of rash, airway disease or other allergic manifestations associated with dust mites. We noticed that the oval structure of mite eggs resembled helminth eggs and therefore may be misidentified during routine clinical analysis. As the patient was otherwise healthy, it was concluded that no rigorous antiparasitic therapy was necessary to eliminate dust mites from his system.

  6. HOUSE DUST MITE ALLERGY IN VIEW OF MOLECULAR ALLERGOLOGY

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    E. S. Korovkina

    2012-01-01

    Full Text Available Abstract. Incidence of allergic diseases is increased over last years. House dust is considered a major risk factor of allergic sensitization which plays an important role in development of allergic rhinitis, bronchial asthma, atopic dermatitis. Dust mites in the home comprise a large part of domestic allergens. Dermatophagoides pteronyssinus, Dermatophagoides farinae, Euroglyphus maynei, Lepidoglyphus destructor, Blomia tropicalis are most important in this respect. Der p 1 and Der p 2 are regarded as major house dust mite allergens. Recent studies concerned induction of IgE responses against mite tropomyosin (Der p 10, an allergen occurring in mites which exhibits high cross-reactivity with tropomyosins from a variety of sea foods (e.g. shrimps, as well as human tropomyosins. Allergen-specific immunotherapy (ASIT represents the only causative approach to allergy treatment in such cases. From this viewpoint, a quantitation of specific IgЕ against major house dust mite allergens would be necessary to predict ASIT efficiency. Treatment by house dust mites allergen extracts is effective in management of allergic rhinitis and mild asthma. A component-resolved diagnostic (CRD with purified house-dust mites allergens allows to discriminate patients who were mostly sensitized to the major house dust mites allergens (e.g. Der p 10, tropomyosin. The component-resolved diagnostics could be performed before starting the allergen-specific immunotherapy by mite allergens, in order to avoid unresponsiveness to this mode of therapy.

  7. Induction of atopic dermatitis by inhalation of house dust mite

    NARCIS (Netherlands)

    Tupker, RA; DeMonchy, JGR; Coenraads, PJ; vanderMeer, JB

    Background: The pathogenetic role of house dust mite in atopic dermatitis remains controversial. Recent studies have shown that intensive epicutaneous contact of house dust mite allergen with premanipulated skin may induce dematitis. It is, however, uncertain whether such conditions are met during

  8. Induction of atopic dermatitis by inhalation of house dust mite

    NARCIS (Netherlands)

    Tupker, RA; DeMonchy, JGR; Coenraads, PJ; vanderMeer, JB

    1996-01-01

    Background: The pathogenetic role of house dust mite in atopic dermatitis remains controversial. Recent studies have shown that intensive epicutaneous contact of house dust mite allergen with premanipulated skin may induce dematitis. It is, however, uncertain whether such conditions are met during n

  9. House dust mites and their allergens at selected locations in the homes of house dust mite-allergic patients

    DEFF Research Database (Denmark)

    Sidenius, K E; Hallas, T E; Brygge, T

    2002-01-01

    Knowledge of the occurrence of house dust mites (HDM) and their allergens in domestic locations is important when planning intervention.......Knowledge of the occurrence of house dust mites (HDM) and their allergens in domestic locations is important when planning intervention....

  10. Randomized double-blind placebo-controlled trial of sublingual immunotherapy in children with house dust mite allergy in primary care: study design and recruitment

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    de Jongste Johan C

    2008-10-01

    Full Text Available Abstract Background For respiratory allergic disorders in children, sublingual immunotherapy has been developed as an alternative to subcutaneous immunotherapy. Sublingual immunotherapy is more convenient, has a good safety profile and might be an attractive option for use in primary care. A randomized double-blind placebo-controlled study was designed to establish the efficacy of sublingual immunotherapy with house dust mite allergen compared to placebo treatment in 6 to18-year-old children with allergic rhinitis and a proven house dust mite allergy in primary care. Described here are the methodology, recruitment phases, and main characteristics of the recruited children. Methods Recruitment took place in September to December of 2005 and 2006. General practitioners (in south-west Netherlands selected children who had ever been diagnosed with allergic rhinitis. Children and parents could respond to a postal invitation. Children who responded positively were screened by telephone using a nasal symptom score. After this screening, an inclusion visit took place during which a blood sample was taken for the RAST test. Results A total of 226 general practitioners invited almost 6000 children: of these, 51% was male and 40% Conclusion Our study was designed in accordance with recent recommendations for research on establishing the efficacy of sublingual immunotherapy; 98% of the target sample size was achieved. This study is expected to provide useful information on sublingual immunotherapy with house dust mite allergen in primary care. The results on efficacy and safety are expected to be available by 2010. Trial registration the trial is registered as ISRCTN91141483 (Dutch Trial Register

  11. Decay of house-dust mite allergen Der f 1 at indoor climatic conditions

    DEFF Research Database (Denmark)

    Sidenius, Kirsten E; Hallas, Thorkil E; Stenderup, Jørgen;

    2002-01-01

    The decay of house-dust mite allergens is important for the outcome of avoidance measures for house-dust mite-allergic patients.......The decay of house-dust mite allergens is important for the outcome of avoidance measures for house-dust mite-allergic patients....

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

    DEFF Research Database (Denmark)

    Steenberg, Tove; Kilpinen, Ole Østerlund

    2014-01-01

    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...... weeks. Overall, combinations of desiccant dusts and fungus conidia seem to hold considerable promise for future non-chemical control of poultry red mites....

  13. Protective effect of the DNA vaccine encoding the major house dust mite allergens on allergic inflammation in the murine model of house dust mite allergy

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    Lee Jaechun

    2006-02-01

    Full Text Available Abstract Background Vaccination with naked DNA encoding antigen induces cellular and humoral immunity characterized by the activation of specific Th1 cells. Objective To evaluate the effects of vaccination with mixed naked DNA plasmids encoding Der p 1, Der p 2, Der p 3, Der f 1, Der f 2, and Der f 3, the major house dust mite allergens on the allergic inflammation to the whole house dust mites (HDM crude extract. Methods Three hundred micrograms of these gene mixtures were injected into muscle of BALB/c mice. Control mice were injected with the pcDNA 3.1 blank vector. After 3 weeks, the mice were actively sensitized and inhaled with the whole house dust mite extract intranasally. Results The vaccinated mice showed a significantly decreased synthesis of total and HDM-specific IgE compared with controls. Analysis of the cytokine profile of lymphocytes after challenge with HDM crude extract revealed that mRNA expression of interferon-γ was higher in the vaccinated mice than in the controls. Reduced infiltration of inflammatory cells and the prominent infiltration of CD8+ T cells were observed in histology of lung tissue from the vaccinated mice. Conclusion Vaccination with DNA encoding the major house dust mite allergens provides a promising approach for treating allergic responses to whole house dust mite allergens.

  14. FDA Approves New Treatment for Dust Mite Allergies

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_163882.html FDA Approves New Treatment for Dust Mite Allergies Odactra ... life," said Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research. "The approval ...

  15. Do other components of bedding dust affect sensitisation to house dust mites?

    Science.gov (United States)

    Smith, Claire; Stanley, Thorsten; Crane, Julian; Siebers, Robert

    2011-01-01

    Bedding dust is a mixture of many components, of which the house dust mite (HDM) allergen, Der p 1, is the most allergenic. There has been little work to investigate the effect of other bedding dust components on HDM sensitisation. The objective of the study was to determine the effect of endotoxin in bedding dust on the allergic response in HDM-sensitised individuals. Twenty-nine house dust mite-sensitised adults were skin prick and allergen patch tested against a sterile solution of their own bedding dust and against a solution containing the same concentration of Der p 1 as the bedding solution for comparison. There was no significant difference in wheal size between the diluted house dust mite solution and the bedding dust in spite of their high levels of endotoxin. Symptomatic subjects had larger, but not statistically significant, responses to commercial house dust mite solution than asymptomatic subjects. Allergen patch test responses were negative in 22/29 of subjects using either bedding dust solutions or comparable diluted house dust mite solutions. An individual's own bedding dust does not appear to contain factors that enhance skin prick test or atopy patch test responses to house dust mites.

  16. House dust mites: a risk factor to be considered for occupational safety or source of work-related allergens.

    Science.gov (United States)

    Saleh, Ahmed Megahed Ahmed; Ali, Hisham Abd El-Raouf; Ahmed, Salwa Abdalla Mohamed; Mohammad, Naema Mahmoud; Morsy, Tosson A

    2013-12-01

    House dust mites (HDM) can be found worldwide where human beings live independent from the climate and are a major source of multiple allergens. Mite allergens sensitize and induce perennial rhinitis, asthma, or atopic dermatitis in a large portion of patients with allergic disease particularly children. There is convincing evidence that avoidance of mite allergen can effectively reduce allergic symptoms. This study examined dust from a military hospital and the private home of some nursing staff. A total of seven species of mites belonging to six genera were recovered. The commonest species was Dermatophagoides farinae followed by D. pteronyssinus and the lowest Laelaps nuttalli. Besides, the 7th mite or Parasitus consanguineous live free on dust as a bio-control agent of mites. The presence of mites in and out doors in a hospital and dwellings of medical personnel pave the way to consider HDM as occupational or nosocomial Allergens.

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

    Science.gov (United States)

    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 gallinae.

  18. SQ house dust mite (HDM) SLIT-tablet provides clinical improvement in HDM-induced allergic rhinitis

    DEFF Research Database (Denmark)

    Klimek, Ludger; Mosbech, Holger; Zieglmayer, Petra

    2016-01-01

    House dust mite (HDM) allergy represents a highly prevalent inhalant allergy, and exposure to HDM allergens results in allergic rhinitis with persistent symptoms that may not be adequately controlled with available allergy pharmacotherapy. Allergy immunotherapy constitutes a complementary treatme...

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

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Steenberg, Tove

    2009-01-01

    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....... 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...... 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....

  20. Control of poultry red mites

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Steenberg, Tove

    2008-01-01

    The poultry red mite (PRM), Dermanyssus gallinae, is the most important ectoparasite in European egg production. The mites hide in cracks and crevices in the near vicinity of the resting places of the birds, coming out to feed mainly during the night. Under favourable conditions the population can...... grow rapidly, leading to serious problems. Large mite populations may cause anaemia or even death to the poultry, but also in lower numbers mites may be a nuisance to the birds causing decreased egg production and egg quality. Furthermore, they may have the potential of acting as reservoir....../carriers for various micro-organisms e.g. Salmonella. In SAFEHOUSE, an EU-project running from 2006-2009, partners from 11 European countries aim at developing new methods for prevention and control of Salmonella in egg production systems with particular focus on the transition to enriched cages in the EU. Enriched...

  1. Effect of mattress and pillow encasings on children with asthma and house dust mite allergy

    DEFF Research Database (Denmark)

    Halken, Susanne; Høst, Arne; Niklassen, Ulla

    2003-01-01

    BACKGROUND: House dust mite (HDM) allergy is a frequent cause of allergic asthma in children. Reduction of exposure seems to be the most logical way to treat these patients. OBJECTIVE: Our aim was to investigate whether mattress and pillow encasings resulted in an effective long-term control of H...

  2. Stability evaluation of house dust mite vaccines for sublingual immunotherapy

    Directory of Open Access Journals (Sweden)

    MARIJA GAVROVIĆ-JANKULOVIĆ

    2010-01-01

    Full Text Available Allergen-specific immunotherapy with house dust mite (HDM allergen extracts can effectively alleviate the symptoms of allergic rhinitis and asthma. The efficacy of the immunotherapeutic treatment is highly dependent on the quality of house dust mite vaccines. This study was performed to assess the stability of house dust mite allergen vaccines prepared for sublingual immunotherapy. Lyophilized Dermatophagoides pteronyssinus (Dpt mite bodies were the starting material for the production of sublingual vaccines in four therapeutic concentrations. The stability of the extract for vaccine production, which was stored below 4 °C for one month, showed consistence in the protein profile in SDS PAGE. ELISA-inhibition showed that the potencies of Dpt vaccines during a 12 month period were to 65–80 % preserved at all analyzed therapeutic concentrations. This study showed that glycerinated Dpt vaccines stored at 4 °C preserved their IgE-binding potential during a 12 month period, implying their suitability for sublingual immunotherapeutic treatment of HDM allergy.

  3. Evidence refuting the contribution of the fungus Aspergillus penicillioides to the allergenicity of the house dust mite Dermatophagoides pteronyssinus.

    Science.gov (United States)

    Hay, D B; Hart, B J; Douglas, A E

    1992-01-01

    This communication demonstrates unequivocally that the fungi associated with house dust mites do not contribute to mite allergenicity. The evidence is twofold: first, larval mites which lack fungi have allergen profiles indistinguishable from fungus-bearing adult mites. Second, the allergen profile of experimentally-derived fungus-free adult mites and mites re-fed the fungus Aspergillus penicillioides are identical.

  4. A house dust mite allergen homologue from poultry red mite Dermanyssus gallinae (De Geer).

    Science.gov (United States)

    Nisbet, A J; Huntley, J F; Mackellar, A; Sparks, N; McDevitt, R

    2006-08-01

    Tropomyosin is an allergenic, actin-binding protein and a proposed vaccine candidate from several species of parasite. Tropomyosin cDNA, obtained by polymerase chain reaction (PCR) amplification from Dermanyssus gallinae RNA, encoded a predicted protein with 89% and 88% identity to tropomyosins from the ticks Boophilus microplus and Haemaphysalis longicornis, respectively, and 85% identity to the house dust mite (HDM) tropomyosin Der p 10. Mouse antibodies raised against HDM tropomyosin reacted with a band of 38 kDa on Western blots of D. gallinae extract, consistent with the molecular masses of acarine tropomyosins and the putative product of the cDNA encoding D. gallinae tropomyosin. When the same preparation of D. gallinae proteins was used in Western blots with serum from infested hens, the IgY component of the serum bound to a number of mite proteins, but not to tropomyosin, indicating that hens are not directly exposed to this allergen during a natural infestation. Immunolocalization of tropomyosin in mites indicated a ubiquitous distribution of the molecule in mite tissues. Immunolocalization and Western blotting also indicated that poultry red mites ingest host IgY.

  5. Improvement of shrimp allergy after sublingual immunotherapy for house dust mites: a case report.

    Science.gov (United States)

    Cortellini, G; Spadolini, I; Santucci, A; Cova, V; Conti, C; Corvetta, A; Passalacqua, G

    2011-10-01

    The appropriateness of house dust mite specific immunotherapy in patients allergic to shrimps still remains unclear We present a clinical case as an immunological model for the strong sensitization to tropomyosin with symptoms of anaphylaxis due to shrimps and coexisting asthma due to house dust mite. The improvement in respiratory symptoms for house dust mite and in the food challenge for shrimps during mite immunotherapy with a known and high dosage of tropomyosin suggests the hypothesis that efficacy of mite immunotherapy in food allergy to tropomyosin may be dose dependent.

  6. House dust-mite allergen exposure is associated with serum specific IgE but not with respiratory outcomes.

    NARCIS (Netherlands)

    Bakolis, I.; Heinrich, J.; Zock, J.P.; Norbäck, D.; Svanes, C.; Chen, C.M.; Accordini, S.; Verlato, G.; Olivieri, M.; Jarvis, D.

    2015-01-01

    Exposure to house dust has been associated with asthma in adults, and this is commonly interpreted as a direct immunologic response to dust-mite allergens in those who are IgE sensitized to house dust-mite. Mattress house dust-mite concentrations were measured in a population-based sample of 2890

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

    Science.gov (United States)

    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.

  8. Requirements for acquiring a high-quality house dust mite extract for allergen immunotherapy

    Directory of Open Access Journals (Sweden)

    Frati F

    2012-05-01

    Full Text Available Franco Frati,1 Cristoforo Incorvaia,2 Marie David,3 Silvia Scurati,3 Simona Seta,4 Guglielmo Padua,4 Eleonora Cattaneo,1 Carlo Cavaliere,5 Alessia Di Rienzo,6 Ilaria Dell'Albani,1 Paola Puccinelli11Medical and Scientific and Regulatory Department, Stallergenes, Milan, Italy; 2Allergy/Pulmonary Rehabilitation, ICP Hospital, Milan, Italy; 3Laboratoire Stallergenes, Antony, France; 4Marketing Department, Stallergenes, Milan, Italy; 5Ear, Nose and Throat Department, University Sapienza, Rome, Italy; 6Azienda Sanitaria Locale, Allergology Service, Frosinone, ItalyAbstract: The house dust mite is a major cause of respiratory allergy worldwide. The management of mite allergy is based on avoidance measures, drug treatment, and allergen immunotherapy, but only allergen immunotherapy is able to modify the natural history of the disease. Injectable subcutaneous immunotherapy was introduced a century ago, while sublingual immunotherapy was proposed in the 1980s and emerged in the ensuing years as an effective and safe option to subcutaneous immunotherapy. However, the quality of the extracts to be used in allergen immunotherapy is crucial for the success of treatment. The mite extract for sublingual immunotherapy known as Staloral 300 was developed to offer optimal characteristics concerning the mite culture medium, standardization, and allergen dose. Double-blind, placebo-controlled trials with Staloral 300 have provided a substantial part of the clinical evidence analyzed in a meta-analysis of the efficacy of allergen immunotherapy in mite-induced rhinitis and asthma. Safety and tolerability are very good, mild local reactions in the mouth being the most common side effect. This makes it feasible to carry out sublingual immunotherapy for the 3–5-year duration needed to achieve long-lasting tolerance to the specific allergen. The performance of Staloral 300 may provide optimal conditions for an effective and safe sublingual immunotherapy in patients with

  9. [Control strategies against Varroa mites].

    Science.gov (United States)

    Lodesani, M

    2004-06-01

    In many cases, the easiest way to control a pest or a pathogen is to resort to chemical treatments. In the short period this option is often the most convenient economically and usually does not require refined knowledge of the biology of the pest. Many efforts have been directed to develop chemical treatments against Varroa destructor Anderson & Trueman. Nowadays, product based on organic acids, essential oils, pyrethroids, organophosphate, and formamidine are available. Resistance is serious problem in the chemotherapy of parasites and pathogens of the honeybee. High-level resistance to several active substances (the pyrethroids acrinathrin, flumethrin, fluvalinate; the organophosphate coumaphos; the formamidine amitraz) was detected with laboratory assays in different varroa populations and caused failure of the control in the field. At the end of the '80s, products based on pyrethroids, very effective against the mite, but without any appreciable side effect on bees, became available. Resistance to fluvalinate in Italy and later in other countries caused serious damage to beekeeping; early detection was crucial to reduce losses. The problem of developing suitable treatments was difficult in the case of the varroa mite because most substances active against V. destructor have unacceptable side effects on bees. The idea that the mite could be controlled indefinitely with these strategies began to gain ground.

  10. Child car seats – a habitat for house dust mites and reservoir for harmful allergens

    Directory of Open Access Journals (Sweden)

    David Clarke

    2015-02-01

    Full Text Available [b]Introduction and objective[/b]. House dust mites produce allergens which can cause or aggravate diseases such as asthma, eczema and rhinitis. The objectives of this study are to quantify typical house dust mite and Der p 1 allergen levels in child car seats, and to determine external variables that may influence mite populations in cars. [b]Materials and Methods[/b]. Dust samples were collected from the child car seats and driver seats of 106 cars using a portable vacuum sampling pump over a two minute sampling period. Mites were counted and identified and results were expressed as mites per gram (mites/g of dust, while Der p 1 content of samples were measured by enzyme-linked immunosorbent assay (ELISA. Questionnaires were completed by participants to identify environmental and behavioural effects on mite populations. Results were analysed using General Linear Model (GLM procedures. [b]Results[/b]. Twelve species of mites, of which nine are known to produce harmful allergens, were recorded from 212 dust samples. Over 80% of drivers’ seats and over 77% of child car seats harboured dust mites with a significant correlation (p = 0.001 between the mites/g of dust and Der p 1 content recovered from each seat. A mean of 53 mites/g of dust per seat was recovered, with a mean Der p 1 level of 1.1µg/g. Over 12% of driver seats and 15% of child car seats contained house dust mite levels sufficient to be risk factors for sensitisation and allergic reactions. [b]Conclusions[/b]. Child car seats and driver seats are habitats to a range of mite species which can be present in sufficient concentrations to cause or aggravate allergen related illnesses in individuals who are genetically predisposed.

  11. 226 Analysis of an After-Care Questionnaire in Allergic People to Dust Mites Using Anti-Dust Mites Bed Covers

    OpenAIRE

    Boukhettala, Nabile; Bourgeon, Solveig

    2012-01-01

    Background The goal of the study was to assess in a declarative way, the symptoms felt by the patients and the impact of micro-woven cotton (MWC) and a non woven polyester polyamide (NWP) anti-dust mites bed covers on allergic volunteers to dust mites. Methods This study is a descriptive survey based on an after-care questionnaire handed out to a group of 419 volunteers allergic to dust mites. 109 questionnaires have been used. Regarding the allergy, we asked questions in order to assess the ...

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

    Science.gov (United States)

    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.

  13. [The relationship between the skin allergy test and house dust mites].

    Science.gov (United States)

    Atambay, Metin; Aycan, Ozlem M; Yoloğlu, Saim; Karaman, Ulkü; Daldal, Nilgün

    2006-01-01

    Since 1960 it has been known that house dust mites are related to allergy and that they cause pulmonary tract diseases. There are various house dust mites and among these Dermatophagoides pteronyssinus (Trouessart, 1897) and Dermatophagoides farinae (Hughes, 1961) are best known with regard to their medical importance and morphological characteristics. Skin tests are used to determine the role of mites in allergic diseases. The tests are performed by using D. pteronyssinus and D. farinae antigens. In order to study, the concordance between the skin test results and the presence of house dust mites, dust samples from the houses of 49 patients diagnosed with allergic diseases who underwent skin tests were taken to investigate the presence of mites in dust. House dust mites were determined in 23 (46.3%) of the houses. Mites were found in the houses of 15 (50.0%) of 30 patients with positive skin test results and 8 (42.0%) of 19 patients with negative skin test results. There was no significant difference between the skin test positivity and negativity in the presence of house dust mites (P>0,005). In conclusion, we thought that it was necessary to evaluate the presence of mites in the houses of people who have allergic symptoms even if they had negative skin test results.

  14. Allergens with Protease Activity from House Dust Mites

    Directory of Open Access Journals (Sweden)

    Manuel Reithofer

    2017-06-01

    Full Text Available Globally, house dust mites (HDM are one of the main sources of allergens causing Type I allergy, which has a high risk of progressing into a severe disabling disease manifestation such as allergic asthma. The strong protease activities of a number of these allergens are thought to be involved in several steps of the pathophysiology of this allergic disease. It has been a common notion that protease activity may be one of the properties that confers allergenicity to proteins. In this review we summarize and discuss the roles of the different HDM proteases in the development of Type I allergy.

  15. Structure of the house dust mite allergen Der f 2

    DEFF Research Database (Denmark)

    Johannessen, Birthe R; Skov, Lars; Kastrup, Jette S

    2005-01-01

    The X-ray structure of the group 2 major allergen from Dermatophagoides farinae (Der f 2) was determined to 1.83 A resolution. The overall Der f 2 structure comprises a single domain of immunoglobulin fold with two anti-parallel beta-sheets. A large hydrophobic cavity is formed in the interior of...... of Der f 2. Structural comparisons to distantly related proteins suggest a role in lipid binding. Immunoglobulin E (IgE) cross-reactivity between group 2 house dust mite major allergens can be explained by conserved surface areas representing IgE binding epitopes....

  16. How relevant are house dust mite-fungal interactions in laboratory culture to the natural dust system?

    Science.gov (United States)

    Hay, D B; Hart, B J; Pearce, R B; Kozakiewicz, Z; Douglas, A E

    1992-11-01

    Both house dust and house dust mites Dermatophagoides pteronyssinus contained a wider range of fungi than laboratory mite cultures. In total, nine species of fungi were isolated from D. pteronyssinus in house dust, and these included three xerophilic species (Eurotium amstelodami, Aspergillus penicillioides and Wallemia sebi) commonly found in laboratory cultures of D. pteronyssinus. It is concluded that mites do interact with a similar range of fungi in natural dust and in laboratory culture, but that the diversity of fungal species in the laboratory is reduced and the density of individual fungal species in culture exceeds that of house dust. In a second experiment, dust samples were incubated at room temperature with 75% relative humidity. The diversity of fungi invariably declined from up to 13 genera to the few species recorded in laboratory culture. This suggests that the dominance of xerophilic fungi in laboratory mite rearings is mediated primarily by low relative humidity, and the exclusion of air-borne spores.

  17. House Dust Mites Confer a Distinct Immunological Feature among Dermatitis

    Directory of Open Access Journals (Sweden)

    Safa Baris

    2016-08-01

    Full Text Available Atopic dermatitis (AD is a heterogeneous disease with regard to clinical phenotype and natural history. We investigated T cell subtypes and cytokine responses in peripheral blood and skin lesions of AD patients with various sensitivities. Immunological studies were performed in 27 subjects: 9 house dust mite (HDM-sensitized; 6 subjects with sensitizations other than HDM; 7 non-allergic AD patients and 5 healthy controls. Among those, skin biopsy samples of 13 subjects were evaluated for immunohistochemical analyses, as well. The mean age was 8.93±5.17 years. HDM-allergic AD emerged as a distinct immunologic phenotype, with higher production of interleukin (IL-4, -5, -2 both at rest and when stimulated by Der p1 or SEB along with higher Th17. As for TH17 cell percentage, it was increased in all AD groups compared to healthy controls, while HDM-allergic group was distinguished with a significantly lower production of IL-17. Patients with sensitizations other than HDM were mostly similar to non-allergic AD, with increased Th17 and CD4+CD69+interferon-gamma (IFN-γ+ T cells percentage. The biopsy of lesional skin showed that HDM-allergic AD had lower IFN-γ and IFN-γ co-expressing CD8+ T cells compared to patients with other sensitizations (p=0.03 and p=0.04, respectively. Among the HDM allergic patients, pairwise comparison of lesional versus non-lesional skin revealed higher CD4+ T cells numbers, expression of forkhead box P3 (Foxp3 and T-cell-specific transcription factor (T-bet (p=0.018, p=0.018, p=0.018, respectively. HDM-allergic AD is a distinct subtype with a predominant skewing in Th2 and higher Th17 cell percentage along with a blunted Th1 response in the skin, all of which may have therapeutic implications.

  18. Effect of mattress and pillow encasings on children with asthma and house dust mite allergy

    DEFF Research Database (Denmark)

    Halken, Susanne; Høst, Arne; Niklassen, Ulla

    2003-01-01

    House dust mite (HDM) allergy is a frequent cause of allergic asthma in children. Reduction of exposure seems to be the most logical way to treat these patients.......House dust mite (HDM) allergy is a frequent cause of allergic asthma in children. Reduction of exposure seems to be the most logical way to treat these patients....

  19. Mechanical ventilation and house-dust mites. Mekanisk ventilation og husstoevmider

    Energy Technology Data Exchange (ETDEWEB)

    Korsgaard, J. (Lungeklinikken, Aarhus Kommunehospital, Aarhus (DK))

    1991-01-01

    Nationally and internationally, it is recognised that the rational way to reduce inhabitant exposure to house-dust meters in a temperate climate is to reduce indoor absolute humidity to a level below 7.0 g/kg in the dry winter period. Consequently, it is medically recommended to install mechanical ventilation as environmental treatment of patients with chronic asthma caused by indoor exposure to house-dust mites. In this controlled investigation on the effect of mechanical ventilation on indoor climate conditions, it is documented that the establishment of a basic ventilation rate of 0.5 ach implies a significant reduction in the occurrence of house-dust mites in dwellings. Parallel with this effect, the rate of inside condensation on double-glazed windows was reduced, and the reported complaint rate of humid air, stuffy and dustry air and the indoor smelling sensation were reduced by a factor 2 to 7. No side effects relating to ventilation equipment were reported. It is conclued that the installation of mechanical ventilation in the treatment of mite allergy should be individualized with recommended air exchange rates adjusted to the actual size of dwelling and number of inhabitants. Furthermore care should be taken to avoid risk of condensation in the ventilation equipment. (author).

  20. House-dust mites in our homes are a contamination from outdoor sources

    DEFF Research Database (Denmark)

    Hallas, Thorkil E.

    2010-01-01

    Avoidance advices for house-dust mite sensitized persons are currently based upon the idea, that the mites (Dermatophagoides spp.) are part of the indoor fauna. A closer look at development stages in the house-dust samples shows, however, that only the mites' active stages are present there and t...... no effect of avoidance measures. The verification of the entire hypothesis or part of it may have great impact on the management of the disease house-dust mite allergy.......Avoidance advices for house-dust mite sensitized persons are currently based upon the idea, that the mites (Dermatophagoides spp.) are part of the indoor fauna. A closer look at development stages in the house-dust samples shows, however, that only the mites' active stages are present...... there and that the stages between them, the inactive moulting stages, are absent. Therefore the mites probably do not carry out their life cycles in our dwellings, but are more likely contaminations from the open. Findings of low level concentrations can be explained by mites coming from outdoors and sedimented...

  1. Immunoinformatics and Similarity Analysis of House Dust Mite Tropomyosin

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Ranjbar

    2015-10-01

    Full Text Available Background: Dermatophagoides farinae and Dermatophagoides pteronyssinus are house dust mites (HDM that they cause severe asthma and allergic symptoms. Tropomyosin protein plays an important role in mentioned immune and allergic reactions to HDMs. Here, tropomyosin protein from Dermatophagoides spp. was comprehensively screened in silico for its allergenicity, antigenicity and similarity/conservation.Materials and Methods: The amino acid sequences of D. farinae tropomyosin, D. pteronyssinus and other mites were retrieved. We included alignments and evaluated conserved/ variable regions along sequences, constructed their phylogenetic tree and estimated overall mean distances. Then, followed by with prediction of linear B-cell epitope based on different approaches, and besides in-silico evaluation of IgE epitopes allergenicity (by SVMc, IgE epitope, ARPs BLAST, MAST and hybrid method. Finally, comparative analysis of results by different approaches was made.Results: Alignment results revealed near complete identity between D. farina and D. pteronyssinus members, and also there was close similarity among Dermatophagoides spp. Most of the variations among mites' tropomyosin were approximately located at amino acids 23 to 80, 108 to 120, 142 to 153 and 220 to 230. Topology of tree showed close relationships among mites in tropomyosin protein sequence, although their sequences in D. farina, D. pteronyssinus and Psoroptes ovis are more similar to each other and clustered. Dermanyssus gallinae (AC: Q2WBI0 has less relationship to other mites, being located in a separate branch. Hydrophilicity and flexibility plots revealed that many parts of this protein have potential to be hydrophilic and flexible. Surface accessibility represented 7 different epitopes. Beta-turns in this protein are with high probability in the middle part and its two terminals. Kolaskar and Tongaonkar method analysis represented 11 immunogenic epitopes between amino acids 7-16. From

  2. Control of poultry red mites

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Steenberg, Tove

    2008-01-01

    The poultry red mite (PRM), Dermanyssus gallinae, is the most important ectoparasite in European egg production. The mites hide in cracks and crevices in the near vicinity of the resting places of the birds, coming out to feed mainly during the night. Under favourable conditions the population can...... grow rapidly, leading to serious problems. Large mite populations may cause anaemia or even death to the poultry, but also in lower numbers mites may be a nuisance to the birds causing decreased egg production and egg quality. Furthermore, they may have the potential of acting as reservoir...

  3. Effect of mattress and pillow encasings on children with asthma and house dust mite allergy

    DEFF Research Database (Denmark)

    Halken, Susanne; Høst, Arne; Niklassen, Ulla

    2003-01-01

    BACKGROUND: House dust mite (HDM) allergy is a frequent cause of allergic asthma in children. Reduction of exposure seems to be the most logical way to treat these patients. OBJECTIVE: Our aim was to investigate whether mattress and pillow encasings resulted in an effective long-term control of HDM...... allergen levels, thereby reducing the need for asthma medication in children with asthma and HDM allergy. METHODS: In a prospective, double-blind, placebo-controlled study 60 children (age range, 6-15 years) with asthma and HDM allergy were randomized to active (allergy control) or placebo mattress...... children with asthma and HDM allergy....

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

    DEFF Research Database (Denmark)

    Steenberg, Tove; Kilpinen, Ole Østerlund

    2014-01-01

    , 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...

  5. HOUSE DUST MITE CONTAMINATION IN HOTELS AND INNS IN BANDAR ABBAS, SOUTH OF IRAN

    Directory of Open Access Journals (Sweden)

    M. Soleimani, J. Rafinejad

    2008-07-01

    Full Text Available House dust mites have been shown to be strongly associated with allergic respiratory diseases such as, bronchial asthma, rhinitis and atopic dermatitis in the world. The climatic conditions of Bandar-Abbas, which is located in a coastal area and has a humid subtropical climate, provide a suitable place to proliferate mites. The aim of this study was to determine the contamination rate and analyze the house dust mite fauna in hotels and inns in Bandar-Abbas that had not been investigated previously. In this study 6 hotels and 6 inns were selected randomly in six areas of Bandar-Abbas. Two dust samples were collected from each place with a vacuum cleaner. One square meter of carpets and mattresses were vacuumed for a period of 1 min. Then the samples were cleared in lactic acid and then mites were mounted in Hoyer's medium for study and identification. A total of 2644 mites were collected and identified. The major mite family was Pyroglyphidae (98%. Dermatophagoides pteronyssinus was the most frequent and most numerous species recorded, occurring in 91% of samples examined and forming 88% of the Pyroglyphidae and 86% of the total mite populations. The family Cheyletidae was less commonly found with Cheyletus malaccensis (2%. Most of the mites were isolated from the carpets (57.5%, and a smaller number from mattresses (42.5%. Mites were present in 96% of the dust samples. Results revealed that all inns and 83% of hotels were contaminated by more than one species of mite and 34% of them had a population of more than 100 mites /g dust. This rate of contamination can be a major risk factor in asthma and other respiratory allergic diseases

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

    Institute of Scientific and Technical Information of China (English)

    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 LC50 of either essential oils or monoterpenoids against the mite was time dependant. The LC50 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.

  7. [Sensitization to house dust and storage mites in allergic adults from the South of Mexico city].

    Science.gov (United States)

    Ramírez-Heredia, Jennifer; Oífarrill-Romanillos, Patricia María; Guidos-Fogelbach, Guillermo; Miyagui-Nakamura, Roberto Ken; Segura-Méndez, Nora Hilda

    2013-01-01

    Mites are the most common cause of respiratory allergy. Sensitization to house dust mites is estimated at 30%. Families Euroglyphus and Dermatophagoides, are the most important. Recently, storage mites, from the families Acaridae and Glyciphagidae, have become more important as a cause of allergic respiratory diseases. The aim of this study was to identify sensitization to house dust and storage mites by skin tests in adult patients with allergic respiratory diseases. This is a descriptive study in patients with asthma and/or allergic rhinitis, with the approval of the local research committee 2009-3601-46. Patients underwent skin prick tests, with seven standardized extracts of mites (IPI ASACR). The results were analyzed with descriptive statistics. A total of 150 patients, 109 women and 41 men, with an average age 31 years (±11) were studied. The more common allergic diseases in this group of patients were: asthma and rhinitis 72 and 26%, respectively, and asthma plus rhinitis 3.2%. Positive skin tests for Dermatophagoides pteronyssinus and Dermatophagoides farinae were 82.1% 71.5%, respectively, and for storage mites: A. siro 51.7%, Tyrophagus 47.4%, Glycyphagus 47.7%, B. tropicalis 39.7% and Lepidoglyphus 39.1%. Storage mites produced greater sensitization than house dust mites, 32% vs 10%. The results show that adult patients with respiratory allergy, in southern Mexico City, have a higher rate of sensitization to storage mites than the one reported in the literature.

  8. SQ house dust mite sublingually administered immunotherapy tablet (ALK) improves allergic rhinitis in patients with house dust mite allergic asthma and rhinitis symptoms

    DEFF Research Database (Denmark)

    Mosbech, Holger; Canonica, G Walter; Backer, Vibeke;

    2015-01-01

    BACKGROUND: House dust mite (HDM) allergy is associated with persistent allergic rhinitis (AR) and allergic asthma. OBJECTIVE: To investigate the efficacy and safety of a SQ HDM sublingually administered immunotherapy tablet (ALK, Hørsholm, Denmark) in adults and adolescents with HDM respiratory ...

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

    Science.gov (United States)

    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…

  10. Efficacy of a House Dust Mite Sublingual Allergen Immunotherapy Tablet in Adults With Allergic Asthma

    DEFF Research Database (Denmark)

    Virchow, J Christian; Backer, Vibeke; Kuna, Piotr;

    2016-01-01

    IMPORTANCE: The house dust mite (HDM) sublingual allergen immunotherapy (SLIT) tablet is a potential novel treatment option for HDM allergy-related asthma. OBJECTIVES: To evaluate the efficacy and adverse events of the HDM SLIT tablet vs placebo for asthma exacerbations during an inhaled corticos......IMPORTANCE: The house dust mite (HDM) sublingual allergen immunotherapy (SLIT) tablet is a potential novel treatment option for HDM allergy-related asthma. OBJECTIVES: To evaluate the efficacy and adverse events of the HDM SLIT tablet vs placebo for asthma exacerbations during an inhaled...... moderate or severe asthma exacerbation during the ICS reduction period. Secondary outcomes were deterioration in asthma symptoms, change in allergen-specific immunoglobulin G4 (IgG4), change in asthma control or asthma quality-of-life questionnaires, and adverse events. RESULTS: Among 834 randomized...... in allergen-specific IgG4. However, there was no significant difference for change in asthma control questionnaire or asthma quality-of-life questionnaire for either dose. There were no reports of severe systemic allergic reactions. The most frequent adverse events were mild to moderate oral pruritus (13...

  11. Rhinovirus exacerbates house-dust-mite induced lung disease in adult mice.

    Directory of Open Access Journals (Sweden)

    Jennifer A Phan

    Full Text Available Human rhinovirus is a key viral trigger for asthma exacerbations. To date, murine studies investigating rhinovirus-induced exacerbation of allergic airways disease have employed systemic sensitisation/intranasal challenge with ovalbumin. In this study, we combined human-rhinovirus infection with a clinically relevant mouse model of aero-allergen exposure using house-dust-mite in an attempt to more accurately understand the links between human-rhinovirus infection and exacerbations of asthma. Adult BALB/c mice were intranasally exposed to low-dose house-dust-mite (or vehicle daily for 10 days. On day 9, mice were inoculated with human-rhinovirus-1B (or UV-inactivated human-rhinovirus-1B. Forty-eight hours after inoculation, we assessed bronchoalveolar cellular inflammation, levels of relevant cytokines/serum antibodies, lung function and responsiveness/sensitivity to methacholine. House-dust-mite exposure did not result in a classical TH2-driven response, but was more representative of noneosinophilic asthma. However, there were significant effects of house-dust-mite exposure on most of the parameters measured including increased cellular inflammation (primarily macrophages and neutrophils, increased total IgE and house-dust-mite-specific IgG1 and increased responsiveness/sensitivity to methacholine. There were limited effects of human-rhinovirus-1B infection alone, and the combination of the two insults resulted in additive increases in neutrophil levels and lung parenchymal responses to methacholine (tissue elastance. We conclude that acute rhinovirus infection exacerbates house-dust-mite-induced lung disease in adult mice. The similarity of our results using the naturally occurring allergen house-dust-mite, to previous studies using ovalbumin, suggests that the exacerbation of allergic airways disease by rhinovirus infection could act via multiple or conserved mechanisms.

  12. Rhinovirus exacerbates house-dust-mite induced lung disease in adult mice.

    Science.gov (United States)

    Phan, Jennifer A; Kicic, Anthony; Berry, Luke J; Fernandes, Lynette B; Zosky, Graeme R; Sly, Peter D; Larcombe, Alexander N

    2014-01-01

    Human rhinovirus is a key viral trigger for asthma exacerbations. To date, murine studies investigating rhinovirus-induced exacerbation of allergic airways disease have employed systemic sensitisation/intranasal challenge with ovalbumin. In this study, we combined human-rhinovirus infection with a clinically relevant mouse model of aero-allergen exposure using house-dust-mite in an attempt to more accurately understand the links between human-rhinovirus infection and exacerbations of asthma. Adult BALB/c mice were intranasally exposed to low-dose house-dust-mite (or vehicle) daily for 10 days. On day 9, mice were inoculated with human-rhinovirus-1B (or UV-inactivated human-rhinovirus-1B). Forty-eight hours after inoculation, we assessed bronchoalveolar cellular inflammation, levels of relevant cytokines/serum antibodies, lung function and responsiveness/sensitivity to methacholine. House-dust-mite exposure did not result in a classical TH2-driven response, but was more representative of noneosinophilic asthma. However, there were significant effects of house-dust-mite exposure on most of the parameters measured including increased cellular inflammation (primarily macrophages and neutrophils), increased total IgE and house-dust-mite-specific IgG1 and increased responsiveness/sensitivity to methacholine. There were limited effects of human-rhinovirus-1B infection alone, and the combination of the two insults resulted in additive increases in neutrophil levels and lung parenchymal responses to methacholine (tissue elastance). We conclude that acute rhinovirus infection exacerbates house-dust-mite-induced lung disease in adult mice. The similarity of our results using the naturally occurring allergen house-dust-mite, to previous studies using ovalbumin, suggests that the exacerbation of allergic airways disease by rhinovirus infection could act via multiple or conserved mechanisms.

  13. Hierarchy and molecular properties of house dust mite allergens

    Directory of Open Access Journals (Sweden)

    Wayne R. Thomas

    2015-10-01

    Full Text Available The allergenic load of house dust mite allergy is largely constituted by a few proteins with a hierarchical pattern of allergenicity. The serodominant specificities are the group 1&2 and the group 23 faecal allergens. The collective IgE binding to the group 1&2 allergens can measure unequivocal HDM sensitisation better than HDM extracts although discrepancies have been found in regions with complex acarofauna suggesting a need to investigate the specificity with allergen components. The group 4, 5, 7&21 allergens that each induce responses in about 40% of subjects are mid-tier allergens accounting for most of the remaining IgE binding. Their titres are proportional to the concomitant responses to Der p1&2. Group 2 allergen variants have different antibody binding. Body proteins only occasionally induce sensitisation although a higher prevalence of binding by atopic dermatitis patients provides a new avenue of research. A broad spectrum of IgE binding has been associated with diverse symptoms but not with the severity of asthma which is associated with low IgG antibody. Some allergens such as the group 14 large lipid binding proteins and the recently described proteins Der f 24–33, need further investigation but with the cognoscence that other denominated allergens have been found to be minor sensitisers by comparative quantitative analyses. Scabies is a confounder for diagnosis with extracts, inducing cross-reactive antibodies with Der p 4&20 as is seafood allergy with cross reactivity to Der p 10 a minor HDM allergen. The HDM genome sequence can now be used to verify allelic and paralogous variations.

  14. Hierarchy and molecular properties of house dust mite allergens.

    Science.gov (United States)

    Thomas, Wayne R

    2015-10-01

    The allergenic load of house dust mite allergy is largely constituted by a few proteins with a hierarchical pattern of allergenicity. The serodominant specificities are the group 1&2 and the group 23 faecal allergens. The collective IgE binding to the group 1&2 allergens can measure unequivocal HDM sensitisation better than HDM extracts although discrepancies have been found in regions with complex acarofauna suggesting a need to investigate the specificity with allergen components. The group 4, 5, 7&21 allergens that each induce responses in about 40% of subjects are mid-tier allergens accounting for most of the remaining IgE binding. Their titres are proportional to the concomitant responses to Der p1&2. Group 2 allergen variants have different antibody binding. Body proteins only occasionally induce sensitisation although a higher prevalence of binding by atopic dermatitis patients provides a new avenue of research. A broad spectrum of IgE binding has been associated with diverse symptoms but not with the severity of asthma which is associated with low IgG antibody. Some allergens such as the group 14 large lipid binding proteins and the recently described proteins Der f 24-33, need further investigation but with the cognoscence that other denominated allergens have been found to be minor sensitisers by comparative quantitative analyses. Scabies is a confounder for diagnosis with extracts, inducing cross-reactive antibodies with Der p 4&20 as is seafood allergy with cross reactivity to Der p 10 a minor HDM allergen. The HDM genome sequence can now be used to verify allelic and paralogous variations.

  15. [Risk factors for recurrent wheezing in infants and young children suffering from dust mite allergy after their first wheezing].

    Science.gov (United States)

    Yang, Yan-Zhen; Cai, Meng-Yun; Zhang, Bao-Zhong; Zhou, Bing-Xin; Chen, Rou; Fang, Run-Tao

    2016-12-01

    To investigate the risk factors for recurrent wheezing in infants and young children suffering from dust mite allergy after their first wheezing. A total of 1 236 infants and young children who experienced a first wheezing episode and were hospitalized between August 2014 and February 2015 were enrolled, among whom 387 were allergic to dust mites. These infants and young children were followed up to 1 year after discharge. A total of 67 infants and young children who experienced 3 or more recurrent wheezing episodes within 1 year were enrolled as the recurrent wheezing group, while 84 infants and young children who did not experience recurrent wheezing during follow-up were enrolled as the control group. Univariate analysis and multivariate logistic stepwise regression analysis were performed to investigate the risk factors for recurrent wheezing in these patients. The univariate analysis showed that the age on admission, wheezing time before admission, Mycoplasma pneumoniae infection rate, and influenza virus infection rate were associated with recurrent wheezing. The multivariate logistic stepwise regression analysis showed that the older age on admission (OR=2.21, P=0.04) and Mycoplasma pneumoniae infection (OR=3.54, P=0.001) were independent risk factors for recurrent wheezing. Infants and young children who are allergic to dust mites, especially young children, have a significantly increased risk of recurrent wheezing if they are complicated by Mycoplasma pneumoniae infection during the first wheezing episode.

  16. House dust mite allergen Der f enhanced bronchial epithelial cell cytokine expression

    Institute of Scientific and Technical Information of China (English)

    BAO QING SUN; WEI TANG; ALBERT CHAN; ADRIAN WU; NAN SHAN ZHONG

    2006-01-01

    The house dust mites ( Dermatophagoides farinae, Der f) are the major source of aeroallergens implicated in the expression of atopic disorders, including asthma, allergic rhinitis and atopic dermatitis. In particular, strong circumstantial evidence suggests that house dust mite antigens are important precipitating factors of asthma. Many house dust mite allergens are proteases that can elicit airway inflammation by stimulating the release of cytokines from bronchial epithelial cells. To investigate whether Derf allergen proteases induced cytokine production from the epithelial cell line BEAS-2B,BEAS-2B cells were cultured with 4 different concentrations of Derf (0.02, 0.2, 2, 20 μg/ml) for 24-96 h, after which supernatants were assayed for interleukin (IL)-6 and IL-8 with ELISA. Reverse transcription-PCR was also performed. The cell sheets were intact throughout the observation in control group without any exposure to Derf antigen. In the experimental groups cells treated with Der f allergen showed changes in the anchorage status of the monolayer. There was a significant increase in the level of cytokine production compared with the untreated sample. The release of IL-6 and IL-8 increased in a concentration-dependent manner ( P < 0.05, respectively) with the addition of increasing dosage of Der f to the cell sheets. Levels of IL-6 and IL-8 began to rise at 24 h and 48 h after allergen exposure, and they increased significantly in the supernatants at 72 h and 96 h. At the same time the concentration dependence of induction of IL-6 and IL-8 expression as well as an increase in the expression of IL-6 and IL-8 mRNA manifested evidently. HDM-induced airway inflammation may include Der f-mediated release of inflammatory mediators, and the proteolytic activity of an allergen may stimulate the release of proinflammatory cytokines from human bronchial epithelium. It is suggested that IL-6 and IL-8 production by bronchial epithelial cells may play a role in the

  17. Simulation of temperature and humidity in mattresses to evaluate risks on house dust mite allergy

    Energy Technology Data Exchange (ETDEWEB)

    Van Ginkel, J.T. [OTB Research Inst. for Housing, Urban and Mobility Studies, Delft (Netherlands). Dept. of Sustainable and Healthy Housing

    2004-07-01

    Mattresses and carpets in bedrooms are the main habitats of house dust mites in thermally well-insulated homes. The major source of allergens are the feces of house mites which feed on human skin scales and which extract vapour from the air by hygroscopic secretion. The critical equilibrium humidity (CEH) is the relative humidity at which the rate of water loss is equal to the rate of water uptake. House dust mites live in human habitats where the relative humidity is greater than the CEH. This paper presents a newly developed simulation model which shows the transient and spatial distribution of temperature and humidity levels in a mattress influenced by skin scales and ambient conditions. It was developed in an attempt to reduce risks on house dust mite allergy from mattresses and carpets. Preliminary results indicate that transmission of water vapour occurs much faster than the transmission of heat. It was suggested that a spring mattress has a lower risk for growth of house mites than a foam mattress. 21 refs., 1 tab., 3 figs.

  18. Dust Mites Population in Indoor Houses of Suspected Allergic Patients of South Assam, India

    OpenAIRE

    Dhruba Sharma; Dutta, B. K.; Singh, A. B.

    2011-01-01

    Background. In the present study, quality and quantity of indoor dust mites was evaluated at the residence of 150 atopic allergic patients from four different districts of South Assam. Methods. Suspected patients with case history of allergic disease were selected for indoor survey. Dust samples (500 mg) were collected from the selected patient's house and were analyzed using standard methods. Results. About 60% of the selected patients were found suffering from respiratory disorders and rest...

  19. Allergy to dust mites may contribute to early onset and severity of alopecia areata.

    Science.gov (United States)

    Li, S F; Zhang, X T; Qi, S L; Ye, Y T; Cao, H; Yang, Y Q; McElwee, K J; Zhang, X

    2015-03-01

    A higher risk of allergic diseases such as rhinitis, asthma and atopic eczema (atopic dermatitis) has been reported for patients with alopecia areata (AA) compared with the general population, but the significance of this is still largely unclear. To determine whether serum total or specific IgE play a role in the onset and severity of AA. We tested 461 serum samples from 351 patients with AA and 110 healthy controls (HC) for total IgE (tIgE) and specific IgE (sIgE) by ImmunoCAP-100 or in vitro test (IVT). The absolute value of tIgE was higher in patients with AA than in normal controls (P 120 IU/mL) detected in patients with AA (29.3%) was similar to that of HC (21.8%). Prevalences of raised sIgE against various allergens detected by ImmunoCAP-100 showed that Dermatophagoides pteronyssinus (Der p; 31.1%) and Dermatophagoides farinae (Der f; 29.0%) were the most common allergens. Similar results were found by IVT, with the most common response being against Der p/Der f (29.0%). However, the prevalences of tIgE and sIgE against dust mites (Der p and Der f) in patients with early-onset AA and severe AA were significantly higher than those with late-onset AA and mild AA (P = 0.02, P = 0.02 vs. P = 0.03 and P = 0.001, respectively). Notably, the increases in tIgE and sIgE were independent of atopy history. Allergy to dust mites may have an effect on the immune response in AA, and may contribute to its early onset and severity in patients of Chinese origin. © 2014 British Association of Dermatologists.

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

    Directory of Open Access Journals (Sweden)

    Toktam Ziyaei

    2017-06-01

    Full Text Available 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.

  1. House-dust mite hypersensitivity, eczema, and other nonpulmonary manifestations of allergy

    NARCIS (Netherlands)

    Tupker, RA; de Monchy, JGR; Coenraads, PJ

    1998-01-01

    The pathogenetic role of house-dust mites (HDM) in atopic dermatitis (AD) remains controversial, mainly because there is no common agreement on a provocation test that mimics ordinary exposure to HDM. This is related to the lack of knowledge of the mechanism of how HDM allergens enter the body.

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

    Science.gov (United States)

    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...

  3. Sublingual immunotherapy not effective in house dust mite-allergic children in primary care

    NARCIS (Netherlands)

    de Bot, Cindy M. A.; Moed, Heleen; Berger, Marjolein Y.; Roder, Esther; Hop, Wim C. J.; de Groot, Hans; de Jongste, Johan C.; van Wijk, Roy Gerth; Bindels, Patrick J. E.; van der Wouden, Johannes C.

    2012-01-01

    Background: Sublingual immunotherapy (SLIT) as a therapy for the treatment of allergic rhinitis in children might be acceptable as an alternative for subcutaneous immunotherapy. However, the efficacy of SLIT with house dust mite extract is not well established. Objective: To investigate whether SLIT

  4. Epidermal growth factor receptor signalling contributes to house dust mite-induced epithelial barrier dysfunction

    NARCIS (Netherlands)

    Heijink, I H; van Oosterhout, A; Kapus, A

    2010-01-01

    Impaired airway epithelial barrier function has emerged as a key factor in the pathogenesis of allergic asthma. We aimed to discern the involvement of the epidermal growth factor receptor (EGFR) in allergen-induced epithelial barrier impairment, as we previously observed that house dust mite (HDM) s

  5. Influence of house dust mite impermeable covers on health-related quality of life of adult patients with asthma: results of a randomized clinical trial.

    NARCIS (Netherlands)

    Bemt, L. van den; Vries, M.P. de; Cloosterman, S.G.M.; Thoonen, B.P.A.; Muris, J.W.M.; Goossens, M.; Wesseling, G.; Schayck, C.P. van

    2007-01-01

    The aim of this study was to evaluate the effect of house dust mite impermeable covers on asthma-specific health-related quality of life in adult asthmatic patients that were trained in guided self-management. In a 2-year randomized placebo-controlled clinical trial, information on the quality of li

  6. Influence of house dust mite impermeable covers on health-related quality of life of adult patients with asthma: results of a randomized clinical trial.

    NARCIS (Netherlands)

    Bemt, L. van den; Vries, M.P. de; Cloosterman, S.G.M.; Thoonen, B.P.A.; Muris, J.W.M.; Goossens, M.; Wesseling, G.; Schayck, C.P. van

    2007-01-01

    The aim of this study was to evaluate the effect of house dust mite impermeable covers on asthma-specific health-related quality of life in adult asthmatic patients that were trained in guided self-management. In a 2-year randomized placebo-controlled clinical trial, information on the quality of li

  7. Effect of fluticasone propionate aqueous nasal spray treatment on platelet activating factor and eicosanoid production by nasal mucosa in patients with a house dust mite allergy

    NARCIS (Netherlands)

    I.M. Garrelds (Ingrid); T. De Graaf-In 't Veld (T.); A.P.H. Jansen (A. P H); R. Gerth van Wijk (Roy); F.J. Zijlstra (Freek)

    1994-01-01

    textabstractThe relationship between the release of platelet activating factor (PAF), leukotriene C4/D4/EE (LTC4/D4/E4) and prostaglandin D2 (PGD2) from nasal mucosa in vivo was examined in 24 rhinitis patients allergic to the house dust mite (HDM). During a double blind placebo controlled cross-ove

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

    Science.gov (United States)

    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 (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.

  9. Is permanent parasitism reversible?--critical evidence from early evolution of house dust mites.

    Science.gov (United States)

    Klimov, Pavel B; OConnor, Barry

    2013-05-01

    Long-term specialization may limit the ability of a species to respond to new environmental conditions and lead to a higher likelihood of extinction. For permanent parasites and other symbionts, the most intriguing question is whether these organisms can return to a free-living lifestyle and, thus, escape an evolutionary "dead end." This question is directly related to Dollo's law, which stipulates that a complex trait (such as being free living vs. parasitic) cannot re-evolve again in the same form. Here, we present conclusive evidence that house dust mites, a group of medically important free-living organisms, evolved from permanent parasites of warm-blooded vertebrates. A robust, multigene topology (315 taxa, 8942 nt), ancestral character state reconstruction, and a test for irreversible evolution (Dollo's law) demonstrate that house dust mites have abandoned a parasitic lifestyle, secondarily becoming free living, and then speciated in several habitats. Hence, as exemplified by this model system, highly specialized permanent parasites may drastically de-specialize to the extent of becoming free living and, thus escape from dead-end evolution. Our phylogenetic and historical ecological framework explains the limited cross-reactivity between allergens from the house dust mites and "storage" mites and the ability of the dust mites to inhibit host immune responses. It also provides insights into how ancestral features related to parasitism (frequent ancestral shifts to unrelated hosts, tolerance to lower humidity, and pre-existing enzymes targeting skin and keratinous materials) played a major role in reversal to the free-living state. We propose that parasitic ancestors of pyroglyphids shifted to nests of vertebrates. Later the nest-inhabiting pyroglyphids expanded into human dwellings to become a major source of allergens.

  10. The distribution of dust mite allergen in the houses of patients with asthma

    Energy Technology Data Exchange (ETDEWEB)

    Tovey, E.R.; Chapman, M.D.; Wells, C.W.; Platts-Mills, T.A.

    1981-11-01

    Using an inhibition radioimmunoassay for the major allergen from Dermatophagoides pteronyssinus (antigen P1), we studied the distribution of this dust allergen in the houses of patients with asthma. Both bed and floor dust samples contained a wide range of antigen P1, 100 to 100,000 ng/g of fine dust, and this concentration correlated well with the number of mite bodies (r . 0.81, p less than 0.001). We were unable to detect antigen P1 in the air of undisturbed rooms. However, during domestic activity, between 1 and 30 ng were collected on a filter than sampled air for 45 min at 17 L/min. Using a cascade impactor it was shown that greater than 80% of the airborne antigen P1 was associated with particles greater than 10 mu in diameter. Some of the particles containing allergen could be identified because they formed precipitin rings when impacted onto agarose containing rabbit antimite antiserum. These particles had the physical appearance of mite feces, which are the major source of antigen P1 in mite cultures. The results suggested that natural exposure to this dust allergen allows occasional fecal particles to enter the lungs and that these particles contain very concentrated allergen.

  11. Evaluation of skin sensitivity in dogs bearing allergic dermatitis to standardized allergenic extract of house dust and storage mites

    National Research Council Canada - National Science Library

    Victor E.S. Cunha; Ruppert L. Hahnstadt; Ana Maria B. Soares; João Luiz H. Faccini

    2007-01-01

    The objective of the study was to evaluate whether allergenic extracts of five house dust and storage mite species standardized for humans might be used for the diagnosis of canine atopic dermatitis (CAD...

  12. House-dust mite and mite-and pet-allergens in indoor environment; Dani oyobi dani-allergen, pet-allergen no jittai

    Energy Technology Data Exchange (ETDEWEB)

    Irie, T. [Shinshu Univ., Matsumoto, Nagano (Japan)

    1998-05-31

    In this paper, the actual state of mite and mite-allergen, and the actual state of pet-allergen that the researches thereof proceed gradually in recent years are described. The following findings are obtained as the results of the actual state investigations. In respect to the mite-allergen, airborne mite, particularly I with high allergen activity shows high concentration from fall to winter. The reasons thereof are considered from two aspects, I.e., the fragmentation and suspension of mite-allergen, and the decrease of ventilation frequency, while it can also be explained from a fact that the fit of infantile asthma is most frequent during a period from October to November. Mite-allergen contained in futon dust is about 10 times more than that contained in floor dust. In respect to pet-allergen, although the indoor accumulative amount and airborne concentration of main pet-allergen such as cat-, and dog-allergen varies greatly depending on whether pet is kept indoor or outdoor, the quantities of dog- and cat-allergen are almost of the same order, but 2 to 3-order higher than the quantity of mite-allergen. 9 refs., 9 figs.

  13. Establishing health standards for indoor foreign proteins related to asthma: Dust mite, cat and cockroach

    Energy Technology Data Exchange (ETDEWEB)

    Platts-Mills, T.A.E.; Chapman, M.D.; Pollart, S.M.; Heymann, P.W.; Luczynska, C.M. (Univ. of Virginia, Charlottesville (United States))

    1990-01-01

    There is no doubt that a large number of individuals become allergic to foreign proteins that are predominantly or exclusively present indoors. In each case this immune response can be demonstrated either by immediate skin test responses or by measuring serum IgE antibodies. It has also been obvious for some time that patients presenting with asthma, perennial rhinitis and atopic dermatitis have an increased prevalence of IgE antibodies to these indoor allergens. More recently several epidemiological surveys have suggested that both mite exposure and IgE antibodies are important risk factors for asthma. The present situation is that assays have been developed capable of measuring the presence of mite, cockroach and cat allergens in house dust. Further clinical studies will be necessary to test the proposed standards for mite allergens and to define risk levels for other allergens.

  14. Gene silencing by RNA interference in the house dust mite, Dermatophagoides pteronyssinus.

    Science.gov (United States)

    Marr, Edward J; Sargison, Neil D; Nisbet, Alasdair J; Burgess, Stewart T G

    2015-12-01

    This is the first report of gene silencing by RNA interference (RNAi) in the European house dust mite, Dermatophagoides pteronyssinus, Trouessart, 1897. Using a non-invasive immersion method first developed for the honey bee mite, Varroa destructor, a significant reduction in the expression of D. pteronyssinus glutathione-S-transferase mu-class 1 enzyme (DpGST-mu1) was achieved following overnight immersion in double stranded RNA encoding DpGST-mu1. Although no detrimental phenotypic changes were observed following silencing, this technique can now be used to address fundamental physiological questions and assess the potential therapeutic benefit in silencing D. pteronyssinus target genes in selected domestic situations of high human-mite interface.

  15. House dust mites and their allergens in Danish mattresses -- results from a population based study

    DEFF Research Database (Denmark)

    Sidenius, Kirsten E; Hallas, Thorkil E; Poulsen, Lars K.

    2002-01-01

    The purpose of this study was to identify the level of house dust mites (HDMs) and their allergens in mattresses, not selected on their owners atopic status, and to find associated factors. Dust was collected from 68 mattresses. The recruitment was population-based and conducted during the screen......The purpose of this study was to identify the level of house dust mites (HDMs) and their allergens in mattresses, not selected on their owners atopic status, and to find associated factors. Dust was collected from 68 mattresses. The recruitment was population-based and conducted during...... the screening phase of a HDM intervention study. The visited persons declared to have had a "cold" bedroom the previous winter. HDMs were counted and dust was analysed by ELISA for Der 1 (= Der f 1+ Der p 1+ Der m 1). Multiple regression analysis was carried out to find housing conditions associated with high...... HDM levels. Type of housing, mattress age and self-assessed winter bedroom-temperature explained 47% of Der 1. Median concentrations were 3.77 microg Der 1/g and 1 HDM/0.1 g dust. Both immunochemically and microscopically Dermatophagoides farinae was dominant; D. pteronyssinus less frequent...

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

    Science.gov (United States)

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

    2015-01-01

    Introduction 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. Aim 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. Material and methods 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. Results 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. Conclusions 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. PMID:26015775

  17. A study on the prevalence of house dust mites in Al-Arish city, North Sinai Governorate, Egypt.

    Science.gov (United States)

    El-Sherbiny, Gihad T; El-Sherbini, Eman T; Saled, Nagla Mostafa K; Haridy, Fouad M; Morsy, Ayman T A

    2010-04-01

    Free living mites comprise a huge and various groups of tiny arthropods in the class Arachida, mainly of the Pyroglyphidae family. Exposure to allergens derived from house dust mite (HDM) feces is a postulated risk factor for allergic sensitization, asthma development and asthma morbidity. However, practical and effective method to mitigate these allergens in low-income, urban home environments remains elusive. It well known that (HDM) physiology is greatly affected by hydrothermal microclimatic condition. El Arish has subtropical climate and warm humid summer, such situation are favourable to proliferate house dust mites. As no valid data are available for house dust mites fauna of El Arish, this study was carried out to determine the prevalence and contamination rates of homes in El Arish city. Samples of house dust collected in 2008 from 50 houses in El Arish city were subjected to acarological examination. Acri were found in (34.6 %) of the samples collected from these homes. Results indicated that dust mites were present in all humid environments. Also, hypersensitivity to dust mites was common among patients with asthma.

  18. Cloning, bioinformatics analysis, and expression of the dust mite allergen Der f 5 of Dermatophagoides farinae

    Directory of Open Access Journals (Sweden)

    Yubao Cui

    2012-08-01

    Full Text Available Crude extracts of house dust mites are used clinically for diagnosis and immunotherapy of allergic diseases, including bronchial asthma, perennial rhinitis, and atopic dermatitis. However, crude extracts are complexes with non-allergenic antigens and lack effective concentrations of important allergens, resulting in several side effects. Dermatophagoides farinae (Hughes; Acari: Pyroglyphidae is one of the predominant sources of dust mite allergens, which has more than 30 groups of allergen. The cDNA coding for the group 5 allergen of D. farinae from China was cloned, sequenced and expressed. According to alignment using the VECTOR NTI 9.0 software, there were eight mismatched nucleotides in five cDNA clones resulting in seven incompatible amino acid residues, suggesting that the Der f 5 allergen might have sequence polymorphism. Bioinformatics analysis revealed that the matured Der f 5 allergen has a molecular mass of 13604.03 Da, a theoretical pI of 5.43 and is probably hydrophobic and cytoplasmic. Similarities in amino acid sequences between Der f 5 and allergens of other domestic mite species, viz. Der p 5, Blo t 5, Sui m 5, and Lep d 5, were 79, 48, 53, and 37%, respectively. Phylogenetic analysis indicated that Der f 5 and Der p 5 clustered together. Blo t 5 and Ale o 5 also clustered together, although Blomia tropicalis and Aleuroglyphus ovatus belong to different mite families, viz. Echimyopodidae and Acaridae, respectively.

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

    Institute of Scientific and Technical Information of China (English)

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

    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.

  20. Orchestration of an uncommon maturation cascade of the house dust mite protease allergen quartet

    Directory of Open Access Journals (Sweden)

    Marie-Eve eDumez

    2014-03-01

    Full Text Available In more than 20% of the world population, sensitization to house dust mite (HDM allergens triggers typical allergic diseases such as allergic rhinitis and asthma. Amongst the 23 mite allergen groups hitherto identified, groups 1 are cysteine proteases belonging to the papain-like family whereas groups 3, 6 and 9 are serine proteases displaying trypsin, chymotrypsin and collagenolytic activities, respectively. While these proteases are more likely to be involved in the mite digestive system, they also play critical roles in the initiation and in the chronicity of the allergic response notably through the activation of innate immune pathways. All these allergenic proteases are expressed in mite as inactive precursor form. Until recently, the exact mechanisms of their maturation into active proteases remained to be fully elucidated. Recent breakthroughs in the understanding of the activation mechanisms of mite allergenic protease precursors have highlighted an uncommon and unique maturation pathway orchestrated by group 1 proteases that tightly regulates the proteolytic activities of groups 1, 3, 6 and 9 through complex intra- or intermolecular mechanisms. This review presents and discusses the currently available knowledge of the activation mechanisms of group 1, 3, 6 and 9 allergens of Dermatophagoides pteronyssinus laying special emphasis on their localization, regulation and interconnection.

  1. Ready-to-use house dust mites atopy patch test (HDM-Diallertest), a new screening tool for detection of house dust mites allergy in children.

    Science.gov (United States)

    Benhamou, P H; Kalach, N; Soulaines, P; Donne, N; Dupont, C

    2009-10-01

    to assess the accuracy and safety of a ready-to-use atopy patch test (HDM-Diallertest, DBV Technologies, Paris) in the diagnosis of sensitization to house-dust mite (HDM) allergens in children with or without atopic dermatitis. prospective analysis of a systematic allergic work-up was carried out in 47 children, age 57.4+42 months (mean + SD, range 7 to 176 mo), presenting with isolated or combined atopic dermatitis (AD, n = 28) or other symptoms without AD (control group, n = 19). Children were routinely tested for specific HDM-IgE [against D. pteronyssinus (DPT) and D. farinae (DF)], and skin testing based on HDM (DPT & DF) skin prick test (SPT) and ready-to-use HDM-ATP (HDM-Diallertest), with a reading at 72 hours. 15 children (31.9%) exhibited specific IgE against both DPT and DF, 16 children (34.04%) exhibited positive SPT against DPT and 17 (36.1%) against DF. HDM-Diallertest was positive in 15 cases (31.9%). Among these, 9 exhibited with an eczematous reaction showed an excellent correlation with both SPT and specific IgE for DPT and DF, respectively 93.3%, 97.77%, 90.47%, and 90.47%. The different diagnostic techniques of HDM sensitization neither differ between groups, nor correlated specifically with the different clinical manifestations. No side effect was observed during and after patch testing, except for a local reaction without diffusion outside the local test area. The 3 diagnostic techniques exhibited a comparable level of accuracy for the diagnosis of HDM allergens sensitization. The excellent concordance of the highest class reactions of HDM-Diallertest with the other diagnostic techniques indicates a potential role as a screening tool for the detection of HDM sensitization in infancy.

  2. Isolation and characterization of the 68 kD allergen from house dust mite Dermatophagoides pteronyssinus

    Directory of Open Access Journals (Sweden)

    KATARINA MILOVANOVIĆ

    2009-05-01

    Full Text Available House dust mites (HDM represent a major source of allergens, contributing to the increasing incidence of type I hypersensitivity disease worldwide. Over 30 different IgE-binding proteins from the HDM extract were detected. Although group 1 and 2 have been identified as major allergens, due to the safety and efficacy of allergy diagnosis and immunotherapy, there is a need to carefully evaluate the clinical relevance of other allergens present in the HDM extract. In regard to this, a high molecular mass allergen of about 68 kD was purified from the HDM extract using a combination of gel permeation chromatography and reversed-phase chromatography. The IgG and IgE reactivity of the purified protein were preserved during the purification process, as confirmed by Western blot analysis with polyclonal rabbit antibodies and dot blot analysis with a pool of sera from subjects with house dust mite allergy, respectively. In addition, the IgE reactivity was confirmed using ELISA testing with nine patient sera. The biological potency of the 68 kD allergen was confirmed by skin prick testing in five allergic subjects, suggesting that the high molecular mass allergen is a good candidate for component-resolved diagnosis of house dust mite allergy and eventual therapeutic treatment.

  3. New house dust collection system and its use in a study of asthma in dust mite sensitive children in Raleigh, North Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Lindstrom, A.B.; Beck, M.A.; Henry, M.M.; Barnes, D.M.; Henderson, F.W.

    1993-01-01

    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 dust samples from all potentially relevant domestic substrates, with the primary sampling objective being the retrieval at least 100 mg of sample material. During the winter of 1991-92, dust samples were collected from six different microenvironments in the homes of 49 dust mite sensitive children living in the Raleigh, NC metropolitan area. In addition to the standard antigen immunoassay, the performance of the HDVI was assessed by conducting side by side comparison tests using two alternative antigen collection systems. Microenvironmental antigen concentrations were found to be lognormally distributed within the test homes and within each microenvironment. With the relatively large quantity of sample material collected and the ease with which the HDVI was able to collect samples from a wide variety of substrates, the new unit was determined to be well suited for surface dust and dust mite antigen collection studies.

  4. Comparisons of permethrin formulations and application methods for northern fowl mite control on caged laying hens.

    Science.gov (United States)

    Arthur, F H; Axtell, R C

    1982-05-01

    Formulations of permethrin (Ectiban), a synthetic pyrethroid, as an emulsifiable concentrate (EC), wettable powder (WP), and dust were nearly equally effective for 9 or more weeks for control of the northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), on caged laying hens under environmentally controlled conditions. The permethrin was applied to the vent area as .05% active ingredient (AI) spray of the diluted EC or WP at 40 ml per bird, .1% AI mist of the diluted EC at 20 ml per bird, and 4.5 g per bird of the .25% AI dust. Dilute sprays of .05% permethrin prepared from the EC and WP and applied at 40 ml per bird were more effective in a commercial caged-laying hen house for northern fowl mite control than were .5% sprays of tetrachlorvinphos (Rabon), Ravap, and carbaryl (Sevin). Satisfactory mite control was obtained with .6% permethrin prepared from the EC and misted at the rate of 2.5 ml per bird. Low volume, high concentration misting of permethrin was a promising method for mite control with satisfactory control achieved with .2% AI at 5 ml per bird and .6% AI at 2.5 ml per bird.

  5. Respiratory allergy caused by house dust mites: What do we really know?

    Science.gov (United States)

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

    2015-07-01

    The house dust mite (HDM) is a major perennial allergen source and a significant cause of allergic rhinitis and allergic asthma. However, awareness of the condition remains generally low. This review assesses the links between exposure to HDM, development of the allergic response, and pathologic consequences in patients with respiratory allergic diseases. We investigate the epidemiology of HDM allergy to explore the interaction between mites and human subjects at the population, individual, and molecular levels. Core and recent publications were identified by using "house dust mite" as a key search term to evaluate the current knowledge of HDM epidemiology and pathophysiology. Prevalence data for HDM allergen sensitization vary from 65 to 130 million persons in the general population worldwide to as many as 50% among asthmatic patients. Heterogeneity of populations, terminology, and end points in the literature confound estimates, indicating the need for greater standardization in epidemiologic research. Exposure to allergens depends on multiple ecological strata, including climate and mite microhabitats within the domestic environment, with the latter providing opportunity for intervention measures to reduce allergen load. Inhaled mite aeroallergens are unusually virulent: they are able to activate both the adaptive and innate immune responses, potentially offering new avenues for intervention. The role of HDM allergens is crucial in the development of allergic rhinitis and asthma, but the translation of silent sensitization into symptomatic disease is still incompletely understood. Improved understanding of HDMs, their allergens, and their microhabitats will enable development of more effective outcomes for patients with HDM allergy. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  6. High rate of house dust mite sensitization in a shrimp allergic southern Ontario population.

    Science.gov (United States)

    Rosenfield, Lana; Tsoulis, Michael William; Milio, Kirolos; Schnittke, Meghan; Kim, Harold

    2017-01-01

    Shrimp and house dust mite (HDM) allergies are common in Canadians. Often, both of these allergies occur in the same patient. This may be due to homology of tropomyosin or other potentially shared proteins. The aim of our study was to assess the frequency of house dust mite sensitization in a shrimp allergic Canadian population. We undertook a retrospective chart review of shrimp allergic patients at an outpatient allergy clinic in Kitchener, Ontario, Canada. Our primary endpoint was to assess for presence of HDM sensitization in this population. Patients were categorized into approximate quartiles. We assessed the severity of the shrimp reactions, correlated shrimp skin test size to HDM skin test size, and measured the proportion of patients with atopic symptoms. We identified 95 shrimp allergic patients who were tested for house dust mite. 86 (90.5%) of these patients had a positive skin test to HDM. Patients with a shrimp skin test ≥5 mm were 5.31 times (95% CI, 1.55-18.14; p = 0.008) more likely to exhibit a dust mite skin test ≥5 mm than patients with a shrimp skin test shrimp skin test between 10 and 18 mm having a larger HDM skin test were 3.93 times (95% CI 1.03-14.98, p = 0.045) the odds for a patient with a shrimp skin test size between 3 and 4 mm. We did not find a correlation between shrimp skin test size and shrimp reaction symptom grade (p = 0.301). In our Canadian patients, we found a large majority of shrimp allergic patients to be sensitized to HDM. We found that patients with a large skin test to shrimp were more likely to have a large skin test to HDM compared to those patients with a small skin test to shrimp. We did not find a correlation between shrimp skin test size and shrimp reaction symptom severity. Most of these patients had symptoms of rhinitis and/or asthma that may have been caused by house dust mite allergy.

  7. A milestone in house dust-mite-allergen immunotherapy: the new sublingual tablet S-524101 (actair).

    Science.gov (United States)

    Bahceciler, Nerin N; Babayigit Hocaoglu, Arzu; Galip, Nilufer

    2014-12-01

    Subcutaneous allergen-specific immunotherapy has long been used in the treatment of allergic rhinitis and/or asthma and its efficacy has been confirmed. However, due to the discomfort of injections and the risk of severe adverse reactions, alternative routes of allergen administration have emerged. Delivery of allergens through the mucosal route had been proposed and investigated thoroughly, confirming the sublingual route to be the most efficacious. Later, the efficacy and safety of this route have been documented by numerous controlled trials both for house dust mite (HDM) and pollens. Recently, sublingual orodispersable grass pollen allergen tablets were in use followed by the newly developed HDM allergen tablets with satisfactory clinical results: Moreover, very recently 1 year of HDM tablet treatment was demonstrated to exert its clinical efficacy 1 year after discontinuation of tablet IT. The persistence of efficacy after only 1 year of treatment is a new and promising era. Currently, Sublingual Immunotherapy is the most easily administered and safe treatment option until more immunogenic, less allergenic and more efficient allergen extracts are developed.

  8. The Nottingham energy, health and housing study: reducing relative humidity, dust mites and asthma

    Energy Technology Data Exchange (ETDEWEB)

    Pretlove, S.E.C. [South Bank University, London (United Kingdom); Critchley, R. [Health and Housing Group, Nottingham (United Kingdom); Howard, R. [NEA, Nottingham (United Kingdom); Oreszczyn, T. [University College, London (United Kingdom). The Bartlett

    2002-04-01

    This paper describes the Nottingham energy, health and housing study, a project where seven Nottingham City Council households subject to either fuel poverty or heat poverty have been refurbished to improve the internal environmental conditions and therefore the health of the occupants. The main aim was to provide improvements in ventilation, insulation, draughtproofing and heating control in the dwellings. An intervention study was carried out in the seven dwellings where temperature, relative humidity, health, dust mite numbers and ventilation were measured before the introduction of a range of heating, ventilation and insulation improvements. These were then monitored again a year later. The results of the study indicate that with a limited budget, significant improvements have been realized in the comfort levels of the occupants and in their health. Modelling of the environmental conditions and energy consumption in each dwelling has been carried out using the steady-state Condensation Targeter II model. Comparisons between the model predictions and the measured data show that Condensation Targeter II can be used as an effective tool for selecting the most appropriate design modifications for an individual dwelling and can assess the impact that these modifications will have on the energy efficiency of the dwelling and the health of the occupants. (author)

  9. Alpha-actinin is a new type of house dust mite allergen.

    Directory of Open Access Journals (Sweden)

    Su An

    Full Text Available Main indoor allergens for humans are from house dust mites. There are more than 30 allergens in Dermatophagoides farinae but only fourteen allergens have been identified from this mite including Der f 1-3, 6, 7, 10, 11, 13-18, and 22. A native allergen protein (Der f 24, 90 kDa was purified from D. farinae by gel filtration and anionic exchange liquid chromatography combined with IgE immunodetection. Its primary structure was determined by Edman degradation, mass spectrometry analysis and cDNA cloning. Enzyme-linked immunosorbent assay inhibition tests (ELISA-IT, immunoblots, basophil activation test (BAT and skin prick test (SPT were performed to evaluate the allergenicity. It was identified as an alpha (α-actinin containing a CaM-like domain with EF-hand motifs. Der f 24 reacted to sera from 85.4% (35/41 of patients on western blot analysis. It reduced ∼20% sera IgE reactivity to D. farinae extracts on a competitive ELISA. Eighty percent (8/10 of patients with D. farinae allergy showed positive reactions to Der f 24 in skin prick test. The expression of CD63 on basophils from patients was up-regulated by Der f 24 by ∼5.4-fold. Alpha-actinin was identified as a new type of house dust mite allergen. To the best of our knowledge, this is the first report of α-actinin as an allergen.

  10. Alpha-actinin is a new type of house dust mite allergen.

    Science.gov (United States)

    An, Su; Shen, Chuanbing; Liu, Xiaoyu; Chen, Lingling; Xu, Xuemei; Rong, Mingqiang; Liu, Zhigang; Lai, Ren

    2013-01-01

    Main indoor allergens for humans are from house dust mites. There are more than 30 allergens in Dermatophagoides farinae but only fourteen allergens have been identified from this mite including Der f 1-3, 6, 7, 10, 11, 13-18, and 22. A native allergen protein (Der f 24, 90 kDa) was purified from D. farinae by gel filtration and anionic exchange liquid chromatography combined with IgE immunodetection. Its primary structure was determined by Edman degradation, mass spectrometry analysis and cDNA cloning. Enzyme-linked immunosorbent assay inhibition tests (ELISA-IT), immunoblots, basophil activation test (BAT) and skin prick test (SPT) were performed to evaluate the allergenicity. It was identified as an alpha (α)-actinin containing a CaM-like domain with EF-hand motifs. Der f 24 reacted to sera from 85.4% (35/41) of patients on western blot analysis. It reduced ∼20% sera IgE reactivity to D. farinae extracts on a competitive ELISA. Eighty percent (8/10) of patients with D. farinae allergy showed positive reactions to Der f 24 in skin prick test. The expression of CD63 on basophils from patients was up-regulated by Der f 24 by ∼5.4-fold. Alpha-actinin was identified as a new type of house dust mite allergen. To the best of our knowledge, this is the first report of α-actinin as an allergen.

  11. The Effect of Indoor Environmental Characteristics on the Detection of House Dust Mite Der p2 and Der f2 in Asthmatics

    Directory of Open Access Journals (Sweden)

    Nimet Demirtaş

    2016-12-01

    Full Text Available Objective: Mites in house dust play a prominent role in the development of allergic sensitization and as a triggering factor that impairs disease control in asthma. The aim of the study was to determine whether the concentration of house dust mite allergens is associated with indoor conditions in stable asthmatics. Materials and Methods: During the study period, a total of 97 asthmatic patients were queried with a standard survey for their demographical characteristics and living environment. House dust samples from their houses were collected to quantitatively measure Dermatophagoides farinae (Der f2 and Dermatophagoides pteronyssinus (Der p2 levels by using the Enzyme-linked immunosorbent assay (ELISA method. Results: Using the quantitative ELISA method, measurable levels of mite allergens were found in 54.1% of the houses. Higher antigen detection rate was found in houses with visible mould and in those with moisture. The number of household was found to be significantly higher in houses with antigens than in those without antigens. When the indoor characteristics were evaluated by logistic regression analysis, larger number of household (≥4 was found to be a significant risk factor for the presence of mite allergens. The odds ratio for detecting Der p2 and Der f2 antigen was found to be 5.29 (confidence interval 2.18-12.86 (p<0.001. Conclusion: Mite allergen was detected in the house dusts of more than half of the cases by using quantitative ELISA method. Our results did not found any association between concentrations of allergens and indoor characteristics.

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

    Energy Technology Data Exchange (ETDEWEB)

    Chruszcz, Maksymilian; Pomés, Anna; Glesner, Jill; Vailes, Lisa D.; Osinski, Tomasz; Porebski, Przemyslaw J.; Majorek, Karolina A.; Heymann, Peter W.; Platts-Mills, Thomas A.E.; Minor, Wladek; Chapman, Martin D. (INDOOR Bio.); (UV); (UVHS)

    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 contact 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.

  13. Gene expression in the skin of dogs sensitized to the house dust mite Dermatophagoides farinae.

    Science.gov (United States)

    Schamber, Paz; Schwab-Richards, Rachel; Bauersachs, Stefan; Mueller, Ralf S

    2014-10-01

    Atopic dermatitis is a multifactorial allergic skin disease in humans and dogs. Genetic predisposition, immunologic hyperreactivity, a defective skin barrier, and environmental factors play a role in its pathogenesis. The aim of this study was to analyze gene expression in the skin of dogs sensitized to house dust mite antigens. Skin biopsy samples were collected from six sensitized and six nonsensitized Beagle dogs before and 6 hr and 24 hr after challenge using skin patches with allergen or saline as a negative control. Transcriptome analysis was performed by the use of DNA microarrays and expression of selected genes was validated by quantitative real-time RT-PCR. Expression data were compared between groups (unpaired design). After 24 hr, 597 differentially expressed genes were detected, 361 with higher and 226 with lower mRNA concentrations in allergen-treated skin of sensitized dogs compared with their saline-treated skin and compared with the control specimens. Functional annotation clustering and pathway- and co-citation analysis showed that the genes with increased expression were involved in inflammation, wound healing, and immune response. In contrast, genes with decreased expression in sensitized dogs were associated with differentiation and barrier function of the skin. Because the sensitized dogs did not show differences in the untreated skin compared with controls, inflammation after allergen patch test probably led to a decrease in the expression of genes important for barrier formation. Our results further confirm the similar pathophysiology of human and canine atopic dermatitis and revealed genes previously not known to be involved in canine atopic dermatitis.

  14. Analysis of basophil activation by flow cytometry in pediatric house dust mite allergy.

    Science.gov (United States)

    González-Muñoz, Miguel; Villota, Julian; Moneo, Ignacio

    2008-06-01

    Detection of allergen-induced basophil activation by flow cytometry has been shown to be a useful tool for allergy diagnosis. The aim of this study was to assess the potential of this technique for the diagnosis of pediatric house dust mite allergy. Quantification of total and specific IgE and basophil activation test were performed to evaluate mite allergic (n = 24), atopic (n = 23), and non-allergic children (n = 9). Allergen-induced basophil activation was detected as a CD63-upregulation. Receiver operating characteristics (ROC) curve analysis was performed to calculate the optimal cut-off value of activated basophils discriminating mite allergic and non-allergic children. ROC curve analysis yielded a threshold value of 18% activated basophils when mite-sensitized and atopic children were studied [area under the curve (AUC) = 0.99, 95% confidence interval (CI) = 0.97-1.01, p Analysis of the data obtained with 1.6 microg/ml mite extract defined a cut-off value of 8% activated basophils (AUC = 0.96, 95% CI = 0.91-1.01; p basophils (AUC = 1.0) with 16 microg/ml allergen extract and a sensitivity and specificity of 100%. The same threshold and specificity values were obtained with 1.6 microg/ml extract (AUC = 97%, 95% CI = 0.92-1.02; p basophil activation tests and high specific IgE (>43 kU/l) values for Dermatophagoides pteronyssinus allergen. They also showed positive prick (wheal diameter >1.0 cm) and basophil activation (>87%) tests and high specific IgE (>100 kU/l) with shrimp allergen. Shrimp sensitization was demonstrated by high levels of Pen a 1-specific IgE (>100 kU/l). Cross-reactivity between mite and shrimp was confirmed by fluorescence enzyme immunoassay (FEIA-CAP) inhibition study in these two cases. This study demonstrated that the analysis of allergen-induced CD63 upregulation by flow cytometry is a reliable tool for diagnosis of mite allergy in pediatric patients, with sensitivity similar to routine diagnostic tests and a higher specificity

  15. Increased ventilation rate as way to reduce the exposure to house dust mites and improve the health of asthmatic children - an intervention design

    DEFF Research Database (Denmark)

    Spilak, Michal; Kolarik, Barbara; Gunnarsen, Lars

    2012-01-01

    International field studies have documented that indoor air quality is unsatisfactory in many buildings. The overall hypothesis of this project is that improving the indoor environment in dwellings can improve health and reduce suffering from indoor related diseases such as allergy and asthma...... that have shown a marked increase in incidence all around the world during last decades. The purpose of this study is to investigate the effect of increased ventilation and expected lower exposure to house dust mites on symptoms and medication intake among asthmatic children. This will be done by installing...... for the intervention are children with verified asthma and allergy to house dust mites. Children will be exposed to titration of medication prior to the study and randomly distributed to groups with fake or controlled ventilation system. The intervention will last for nine months in each house and will be blinded...

  16. Control of exposure to mite allergen and allergen-impermeable bed covers for adults with asthma.

    Science.gov (United States)

    Woodcock, Ashley; Forster, Louise; Matthews, Edward; Martin, Jeannett; Letley, Louise; Vickers, Madge; Britton, John; Strachan, David; Howarth, Peter; Altmann, Daniel; Frost, Christopher; Custovic, Adnan

    2003-07-17

    The effectiveness of avoidance of house-dust-mite allergen (Dermatophagoides pteronyssinus 1 [Der p1]) in the management of asthma is uncertain. We conducted a double-blind, randomized, placebo-controlled study of allergen-impermeable bed covers involving 1122 adults with asthma. The primary outcomes were the mean morning peak expiratory flow rate over a four-week period during the run-in phase and at six months and the proportion of patients who discontinued inhaled corticosteroid therapy as part of a phased-reduction program during months 7 through 12. Der p1 was measured in mattress dust in a 10 percent random subsample of homes at entry and at 6 and 12 months. The prevalence of sensitivity to dust-mite allergen was 65.4 percent in the group supplied with allergen-impermeable bed covers (active-intervention group) and 65.1 percent in the control group supplied with non-impermeable bed covers. The concentration of Der p1 in mattress dust was significantly lower in the active-intervention group at 6 months (geometric mean, 0.58 microg per gram vs. 1.71 microg per gram in the control group; P=0.01) but not at 12 months (1.05 microg per gram vs. 1.64 microg per gram; P=0.74). The mean morning peak expiratory flow rate improved significantly in both groups (from 410.7 to 419.1 liters per minute in the active-intervention group, Pimpermeable covers, as a single intervention for the avoidance of exposure to dust-mite allergen, seem clinically ineffective in adults with asthma. Copyright 2003 Massachusetts Medical Society

  17. HOUSE DUST MITE ALLERGEN (Derp1 AND Blot5) LEVELS IN ASTHMATICS' HOME IN HONGKONG

    Institute of Scientific and Technical Information of China (English)

    Bao-qing Sun; Adrian Wu; Albert Chan; Stanley Chik; Dorothy Wong; Nan-shan Zhong

    2004-01-01

    Objective To measure Derpl and Blot5 allergen levels in asthmatics' homes in Hongkong.Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients' house: bed and floor. Derpl and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique.Results The levels of Derpl allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g)and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P=0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derpl and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P< 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 =0 μg/g of dust as compared with Derpl in bed and on the floor (4.3% and 14.5% respectively, P< 0.05).Conclusions Derpl and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus (Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hongkong.

  18. The Effectiveness of Acupuncture Compared to Loratadine in Patients Allergic to House Dust Mites

    Directory of Open Access Journals (Sweden)

    Bettina Hauswald

    2014-01-01

    Full Text Available Background. The aim of this work was to evaluate the clinical effectiveness of acupuncture and its impact on the immune system in comparison to loratadine in the treatment of persistent allergic rhinitis caused by house dust mites. Methods. In this study, 24 patients suffering from persistent allergic rhinitis induced by house dust mites were treated either with acupuncture (n=15 or with loratadine (n=9. The evaluation of the data was based on the subjective and the objective rhinoconjunctivitis symptom scores, specific and total IgE, and interleukins (IL-4, IL-10, and IFN-γ as markers for the activity of Th1 or Th2 cells. Results. The treatments with acupuncture as well as with loratadine were considered effective in the patients’ subjective assessment, whereby the effect of the acupuncture tended to be assessed as more persistent after the end of treatment. A change in the specific or the total IgE was not detectable in either group. The interleukin profile showed the tendency of an increasing IL-10 value in the acupuncture group. The results of the study show that the effectiveness of acupuncture is comparable to that of loratadine. Conclusion. Acupuncture is a clinically effective form of therapy in the treatment of patients suffering from persistent allergic rhinitis. The results indicate the probability of an immunomodulatory effect.

  19. Serological identification of house dust mite allergens in dogs with atopic dermatitis

    Directory of Open Access Journals (Sweden)

    Victor E.S. Cunha

    2012-09-01

    Full Text Available House dust mite antigens have been used for decades to diagnose allergic diseases in humans and animals. The objective of this study was to identify allergens in commercial Dermatophagoides farinae and Blomia tropicalis extracts by immunoblotting using sera from allergic dogs and anti-dog IgE conjugate. The analysis of antigens present in the D. farinae extract (FDA Allergenic using sera from 10 dogs allergic to D. farinae showed that eight sera recognized a band of approximately 102 kDa, eight recognized two bands of 52 to 76 kDa, five recognized one band of approximately 76 kDa, four recognized one band of 31 to 38 kDa, and two recognized one band of 12 to 17 kDa. Immunoblot assays of the B. tropicalis extract (FDA Allergenic using sera from 10 animals allergic to B. tropicalis showed that five sera recognized two bands of 52 to 76 kDa. These results demonstrate the importance of the two house dust mite species for the pathogenesis of canine atopic dermatitis in Brazil. In addition, the results indicate which allergens should be present in allergenic extracts used for diagnosis and allergen-specific immunotherapy.

  20. Prolonged effect of allergen sublingual immunotherapy for house dust mites in elderly patients.

    Science.gov (United States)

    Bozek, Andrzej; Starczewska-Dymek, Liwia; Jarzab, Jerzy

    2017-07-01

    The prolonged effect of allergen immunotherapy is unknown, especially in older patients. To analyze the 3-year effect of sublingual allergen-specific immunotherapy (SLIT) to house dust mites in elderly patients with allergic rhinitis. Forty-seven elderly patients (65.78 ± 4.89 years old) underwent SLIT to house dust mites and were monitored for 3 years and compared with a placebo group. SLIT was performed with the use of oral Staloral 300 SR Der p and Der f 50/50% extract (Stallergens Greer, London, United Kingdom) or placebo. Symptoms and medication score, represented by the average adjusted symptom score (AAdSS), serum level of immunoglobulin (Ig) G4 to Dermatophagoides pteronyssinus, Dermatophagoides farinae, Der p 1, and Der p 2, and quality of life, were assessed immediately after SLIT and 3 years later. The AAdSS was significantly decreased after SLIT, and the level remained low during the 3 years after SLIT compared with placebo. Serum-specific IgG4 against D pteronyssinus, D farinae, Der p 1, and Der p 2 increased during the SLIT trial in the study group. For the 3 years of observation after SLIT, there were no significant changes of specific IgG4 levels against the analyzed allergens compared with results just after SLIT. Quality of life based on the Rhinoconjunctivitis Quality of Life Questionnaire score was significantly decreased in patients who received SLIT, from 1.48 (95% confidence interval 1.33-1.79) to 0.98 (95% confidence interval 0.67-1.07; P mites was observed in elderly patients with allergic rhinitis. Further trials are needed to confirm this effect. ClinicalTrials.gov Identifier: NCT01605760. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  1. Mite allergy and mite exposure in Iceland.

    Science.gov (United States)

    Hallas, Thorkil E; Gislason, Thorarinn; Gislason, David

    2011-01-01

    In this overview of investigations into mite allergy in Iceland and of the current understanding of the sources of exposure, 2 major categories of mite-induced allergies were encountered. The first was house dust mite allergy due to house dust mites from unknown sources, and the second was barn allergy caused by mites connected with the degradation of stored hay. Characteristics of these diseases have been obtained from surveys where skin prick tests were made with commercially available extracts of mites and from zoological investigations where mites had been found in different kinds of dusts relevant for the tested persons. The investigations uncovered a discrepancy between the capital Reykjavik and countryside farms. While the frequencies of sensitization to house dust mites and barn mites are rather similar in the capital area and in the rural area, the exposure to these mites is unexpectedly low in the capital area. Thus, sensitization appears to take place preferably in the rural area.

  2. A study on indoor environment contaminants related to dust mite in dwellings of allergic asthma patients and of healthy subjects.

    Science.gov (United States)

    Feng, M; Yang, B; Zhuang, Y J; Yanagi, U; Cheng, X J

    2012-02-01

    This study investigated the pollution of dust mite allergens in the houses of 30 families and their infection to young allergic asthma patients in Shanghai. Medical records, family information, and dust samples were collected from the dwellings of 15 young allergic asthma patients and 15 healthy subjects. Der 1 allergen, which is a common allergen causing allergic asthma, was measured in collected dust samples using the Pharmacia Uni-CAP System. A significant correlation was found between the number of Der 1 allergens collected from floor surfaces and the number of Der 1 allergens collected from bed surfaces. Some factors influencing Der 1 allergen levels were found in this study. Relative humidity in dwellings was found to be most influential to the allergen levels. The findings suggested that traditional reduction methods for coarse particles, such as opening windows and periodic cleaning of beddings, may be effective in removing dust mite allergens.

  3. Microbiota of Demodex mites from rosacea patients and controls.

    Science.gov (United States)

    Murillo, Nathalia; Aubert, Jérome; Raoult, Didier

    2014-01-01

    Proliferation of Demodex mites is associated with rosacea. Furthermore, Demodex-associated bacteria were suggested to play a role in the pathogenesis of rosacea. We decided to analyze Demodex microbiota. Mites were collected by standardized skin surface biopsies from patients with erythematotelangiectatic, papulopustular rosacea or from control subjects. The microbiota from each mite was characterized by 16S rRNA clone library approach. The 16S rRNA clone library consisted of 367 clones obtained from 73 extracts originating from 5 samples per study group (ETR, PPR or healthy subjects). A total of 86 species were identified with 36 as Demodex-specific microbiota. In the papulopustular group, proportions of Proteobacteria and Firmicutes increased whereas proportion of Actinobacteria decreased. Here, we report preliminary results on the microbiota of Demodex mites based on a molecular approach showing an unexpected diversity. Differences according to the host status need to be confirmed but open new perspectives for diagnostic of rosacea.

  4. Purification and characterization of M-177, a 177 kDa allergen, from the house dust mite Dermatophagoides farinae

    Directory of Open Access Journals (Sweden)

    Akihiro Fujikawa

    1999-01-01

    Full Text Available A high molecular weight allergen, M-177, was recently discovered in the house dust mite, Dermatophagoides farinae (D. farinae. The aims of this study were to develop a conventional purification procedure for M-177 and then to analyze some of the immunochemical properties of M-177. Mite extracts obtained from purified mite bodies were a suitable material for preparing M-177, because the purified mite extract contained large amounts of M-177. The purification of this allergen from the extract was achieved by ethanol fractionation, anion exchange chromatography, and gel filtration chromatography. The purified antigen was immunochemically equivalent to that of a preparation obtained by a previous affinity method using an anti-Mag 3-immobilized column. The yield of this purification procedure was 36.8% of the initial amount of M-177 in the extract, 40-fold greater than that of the previous immunoaffinity method. Our purification method was useful for preparing this allergen. The purified M-177 reacted in skin tests in 11 of 16 miteallergic patients, compared to 10 of 16 with Der f 2. The amount of M-177 in the purified mite extract determined by enzyme-linked immunosorbent assay inhibition was as much as 0.95% of the total protein, which was higher than the amounts of Der f 1 (0.52% and Der f 2 (0.32%. The potent allergenic activity and large amount of M-177 in the mites indicate that it is an important mite allergen.

  5. Effects of the fungus Aspergillus penicillioides on the house dust mite Dermatophagoides pteronyssinus: an experimental re-evaluation.

    Science.gov (United States)

    Hay, D B; Hart, B J; Douglas, A E

    1993-07-01

    In this report the widely-held view that house dust mites benefit from fungal contamination of the dietary substratum is re-examined. The performance of Dermatophagoides pteronyssinus (Acari: Pyroglyphidae) is documented over two successive generations in the presence or absence of the xerophilic fungus Aspergillus penicillioides (Hyphomycetales: Moniliaceae). This fungus reduced survival, development rate, adult length and fecundity of D. pteronyssinus. Detrimental effects of A. penicillioides were proportional to the fungal density. Despite the antagonistic effects of A. penicillioides, a requirement for the fungus was indicated by the poor performance of fungus-free mites in the second generation; sustained culture of D. pteronyssinus in the absence of fungi is probably not possible. It is suggested that fungi may alter the particulate nature of the substratum to the detriment of house dust mites, but also provide micronutrients deficient in the diet.

  6. Effective treatment of house dust mite-induced allergic rhinitis with 2 doses of the SQ HDM SLIT-tablet

    DEFF Research Database (Denmark)

    Demoly, Pascal; Emminger, Waltraud; Rehm, Dorte

    2016-01-01

    BACKGROUND: The SQ HDM SLIT-tablet (ALK) has been developed for treatment of house dust mite (HDM)-induced respiratory allergic disease. OBJECTIVE: This trial investigated the efficacy and safety of the SQ HDM SLIT-tablet in adults with moderate-to-severe HDM-induced allergic rhinitis (AR). METHODS...

  7. Seasonal differences in airway hyperresponsiveness in asthmatic patients : Relationship with allergen exposure and sensitization to house dust mites

    NARCIS (Netherlands)

    vanderHeide, S; deMonchy, JGR; deVries, K; Dubois, AEJ; Kauffman, HF

    Background The degree of airway hyperresponsiveness in allergic asthmatic patients may be influenced by changes in environmental exposure to inhalant allergens. Objective This study investigates the relationship between seasonal changes in exposure to house dust mite (HDM) allergens and non-specific

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

    NARCIS (Netherlands)

    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.

    2006-01-01

    Background Studies of the association between indoor allergen exposure and the development of allergic diseases have often measured allergen exposure at one point in time. Objective 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

  9. ADAM10 mediates the house dust mite-induced release of chemokine ligand CCL20 by airway epithelium

    NARCIS (Netherlands)

    Post, S.; Rozeveld, D.; Jonker, M. R.; Bischoff, R.; van Oosterhout, A. J.; Heijink, I. H.

    2015-01-01

    Background: House dust mite (HDM) acts on the airway epithelium to induce airway inflammation in asthma. We previously showed that the ability of HDM to induce allergic sensitization in mice is related to airway epithelial CCL20 secretion. Objective: As a disintegrin and metalloprotease (ADAM)s have

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

    NARCIS (Netherlands)

    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.

    2006-01-01

    Background Studies of the association between indoor allergen exposure and the development of allergic diseases have often measured allergen exposure at one point in time. Objective 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

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

    Science.gov (United States)

    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...

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

    NARCIS (Netherlands)

    Post, Sijranke; Heijink, Irene; Petersen, A 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,

  13. Protease-activated receptor-2 activation contributes to house dust mite-induced IgE responses in mice

    NARCIS (Netherlands)

    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,

  14. Prevalence of sensitization to the storage mites Acarus siro, Tyrophagus putrescentiae, and Lepidoglyphus destructor in allergic patients with different degrees of sensitization to the house-dust mite Dermatophagoides pteronyssinus

    NARCIS (Netherlands)

    van der Heide, S; Niemeijer, NR; Hovenga, H; de Monchy, JGR; Dubois, AEJ; Kauffman, HF

    The prevalence of sensitization to the storage mites Acarus sire (AS), Tyrophagus putrescentiae (TP), and Lepidoglyphus destructor (LD) was studied in 250 sera of patients with different degrees of sensitization to the house-dust mite Dermatophagoides pteronyssinus (DP) by measuring IgE binding to

  15. Prevalence of sensitization to the storage mites Acarus siro, Tyrophagus putrescentiae, and Lepidoglyphus destructor in allergic patients with different degrees of sensitization to the house-dust mite Dermatophagoides pteronyssinus

    NARCIS (Netherlands)

    van der Heide, S; Niemeijer, NR; Hovenga, H; de Monchy, JGR; Dubois, AEJ; Kauffman, HF

    1998-01-01

    The prevalence of sensitization to the storage mites Acarus sire (AS), Tyrophagus putrescentiae (TP), and Lepidoglyphus destructor (LD) was studied in 250 sera of patients with different degrees of sensitization to the house-dust mite Dermatophagoides pteronyssinus (DP) by measuring IgE binding to e

  16. Allergy to house dust mites in primary health care subjects with chronic or recurrent inflammatory states of respiratory system.

    Science.gov (United States)

    Paszkowski, Jacek; Łopatyński, Jerzy

    2002-01-01

    Chronic and recurrent respiratory tract disorders are a frequent problem in general practice. The purpose of the study was to investigate the role of hypersensitivity to house dust mites in respiratory tract diseases in general practice patients. We tried to assess the influence of determined risk factors exposure on development of respiratory tract allergy. Patients from family practitioners surgeries with chronic or recurrent respiratory tract symptoms who had no diagnosis of allergy were recruited to the study (n = 89). All patients responded to a questionnaire focused on history of symptoms, atopic conditions in family and exposure to determined environmental factors like dwelling conditions, obstetrician history, diet in the first year of life. All patients underwent skin prick test with common inhalant allergens. Families of the patients were asked to participate in the study. Families who agreed to take part also responded to the questionnaire and underwent skin tests. In patients and their families blood samples were taken to determine total IgE and specific IgE antibodies to mites allergens. Dust samples were collected by vacuuming of patients' bedroom carpets and mattresses to determine house dust mites allergens concentration. Data on 30 complete patients family sets of their brotherhood, mother and father were collected. Total and specific serum IgE antibodies were determined by disc enzyme-immunoassay (Analco). Mites allergens concentration in dust was measured by simple Acarex strip test (Nexter). The results of the assays (positive skin tests and/or elevated levels of specific IgE) showed allergy to house dust mites in 24 of 89 study patients from general practitioners surgeries (27%). The prevalence of chronic rhinitis, recurrent bronchitis, chronic or recurrent cough, wheezing, dyspnoea was higher in allergic than in nonallergic subjects. Patients with the diagnosis of allergy to house dust mites had usually worse dwelling conditions. Especially

  17. Immune response to allergens in sheep sensitized to house dust mite

    Directory of Open Access Journals (Sweden)

    Velden Joanne

    2008-10-01

    Full Text Available Abstract Background House dust mite (HDM allergens are a major cause of allergic asthma. Most studies using animal models of allergic asthma have used rodents sensitized with the 'un-natural' allergen ovalbumin. It has only recently been recognized that the use of animal models based on HDM provide a more relevant insight into the allergen-induced mechanisms that underpin human allergic disease. We have previously described a sheep model of human allergic asthma that uses Dermatophagoides pteronyssinus HDM. The present study extends our understanding of the immune effects of HDM and the allergens Der p 1 and Der p 2 in the sheep model of asthma. Methods Peripheral blood sera from non-sensitized (control sheep and sheep sensitized to HDM was collected to determine immunoglobulin (Ig reactivities to HDM, Der p 1 and Der p 2 by ELISA. Bronchoalveolar lavage (BAL fluid collected following allergen challenge was also assessed for the presence of HDM-specific antibodies. To examine the cellular immune response to HDM allergens, T cell proliferation and cutaneous responses were assessed in sensitized and control sheep. Results Strong HDM- and Der p 1-specific IgE, IgG1, IgG2 and IgA serum responses were observed in sensitized sheep, while detectable levels of HDM-specific IgG1 and IgA were seen in BAL fluid of allergen-challenged lungs. In contrast, minimal antibody reactivity was observed to Der p 2. Marked T cell proliferation and late phase cutaneous responses, accompanied by the recruitment of eosinophils, indicates the induction of a cellular and delayed-type hypersensitivity (DTH type II response by HDM and Der p 1 allergen, but not Der p 2. Conclusion This work characterizes the humoral and cellular immune effects of HDM extract and its major constituent allergens in sheep sensitized to HDM. The effects of allergen in HDM-sensitized sheep were detectable both locally and systemically, and probably mediated via enzymatic and immune actions of the

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

    NARCIS (Netherlands)

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

    2012-01-01

    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

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

    NARCIS (Netherlands)

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

    2012-01-01

    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

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

    NARCIS (Netherlands)

    Lesna, I.; Sabelis, M.W.; van Niekerk, T.G.C.M.; Komdeur, J.

    2012-01-01

    o 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

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

    NARCIS (Netherlands)

    Lesna, I.; Sabelis, M.W.; Niekerk, van T.G.C.M.; Komdeur, J.

    2012-01-01

    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

  2. Selective allergy to lobster in a case of primary sensitization to house dust mites.

    Science.gov (United States)

    Iparraguirre, A; Rodríguez-Pérez, R; Juste, S; Ledesma, A; Moneo, I; Caballero, M L

    2009-01-01

    Allergy to only 1 kind of seafood is uncommon. We report a case of selective allergy to lobster. We studied a 30-year-old man who suffered generalized urticaria, facial erythema, and pharyngeal pruritus after eating lobster. He had a more than 10-year history of mild persistent asthma and sensitization to house dust mites. The study was performed by skin prick test, and prick-prick test, oral food challenge, specific immunoglobulin (Ig) E determinations by CAP (Phadia, Uppsala, Sweden) and ADVIA-Centaur (ALK-Abelló, Madrid, Spain), and IgE-immunoblotting. The patient's serum recognized 2 allergens of around 198 kDa and 2 allergens of around 65 kDa from the lobster extract, allergens of around 15, 90, and 120 kDa from Dermatophagoides pteronyssinus extract, and allergens of around 15 and 65 kDa from Dermatophagoides farinae extract. Serum did not recognize purified shrimp tropomyosin. Immunoblot-inhibition assay results indicated cross-reactivity between lobster and mite allergens. This is the first report of selective allergy to lobster.

  3. Dose of house dust mite antigen (P1) inhaled by infants aged one month

    Energy Technology Data Exchange (ETDEWEB)

    Carswell, F.; Clark, J.; Robinson, P.; Platts-Mills, T.A.

    1983-11-01

    A survey of the habitats occupied by 12 infants of one month of age revealed that approximately 10% of their day was spent in conditions of potential exposure to the major (P1) allergen of the house dust mite, Dermatophagoides pteronyssinus. A respiratory pump which reproduced the minute ventilation of an infant was placed in representative infant habitats. The P1 allergen trapped by the filter in this pump was measured as an estimate of infants' allergen intake. Detectable P1 intake was only present when there was active air disturbance (bed making and vacuuming). The average P1 intake was approximately 3 ng P1/24 hours. Comparison of this P1 intake with that which sensitizes in other situations suggests that it is usually inadequate to sensitize infants.

  4. Prevention of house dust mite induced allergic airways disease in mice through immune tolerance.

    Science.gov (United States)

    Agua-Doce, Ana; Graca, Luis

    2011-01-01

    Allergic airways disease is a consequence of a Th2 response to an allergen leading to a series of manifestations such as production of allergen-specific IgE, inflammatory infiltrates in the airways, and airway hyper-reactivity (AHR). Several strategies have been reported for tolerance induction to allergens leading to protection from allergic airways disease. We now show that CD4 blockade at the time of house dust mite sensitization induces antigen-specific tolerance in mice. Tolerance induction is robust enough to be effective in pre-sensitized animals, even in those where AHR was pre-established. Tolerant mice are protected from airways eosinophilia, Th2 lung infiltration, and AHR. Furthermore, anti-CD4 treated mice remain immune competent to mount immune responses, including Th2, to unrelated antigens. Our findings, therefore, describe a strategy for tolerance induction potentially applicable to other immunogenic proteins besides allergens.

  5. Effectiveness of Ectiban, egg oil, Rabon, or Sevin for control of northern fowl mites on laying hens.

    Science.gov (United States)

    McKeen, W D; Loomis, E C; Dunning, L L

    1983-12-01

    Two field trials were conducted on different ranches to compare acaricides for control of northern fowl mite (NFM) on White Leghorn hens. In Trial 1 Ectiban spray and dust treatments were compared to Rabon and Sevin spray-treatments; egg oil, Rabon, and Sevin sprays were tested in Trial 2. Concentration and rates of application followed label recommendations for the registered compounds. In Trial 1 Ectiban spray gave excellent NFM control; Ectiban dust, Rabon, and Sevin spray treatments resulted in poor NFM control. Egg oil and Rabon sprays gave effective NFM control in Trial 2. Sevin, as in Trial 1, gave poor NFM control. The failure of Sevin to control mites both times suggests the possibility of NFM resistance to this chemical.

  6. Sulfur Dust Bag: A Novel Technique for Ectoparasite Control in Poultry Systems.

    Science.gov (United States)

    Murillo, Amy C; Mullens, Bradley A

    2016-07-18

    Animal welfare-driven legislation and consumer demand are changing how laying chickens are housed, thus creating challenges for ectoparasite control. Hens housed in suspended wire cages (battery cages) are usually treated with high-pressure pesticides. This application type is difficult in enriched-cage or cage-free production. Alternatives to pesticide sprays are needed in enriched-cage or cage-free systems. In this study, we tested the efficacy of sulfur dust deployed in "dust bags" for control against the northern fowl mite (Ornithonyssus sylviarum), which causes host stress, decreased egg production, and reduced feed conversion efficiency. Dust bags were hung from the tops of cages or were clipped to the inside front of cages. We also tested permethrin-impregnated plastic strips, marketed for ectoparasite control in caged or cage-free commercial and backyard flocks. Previous work has shown sulfur to be very active against poultry ectoparasites; however, we found that the placement of bags was important for mite control. Sulfur in hanging bags reduced mites on treatment birds by 95 or 97% (depending on trial) within one week of being deployed, and mite counts on these birds were zero after 2 wk. Clipped sulfur bags acted more slowly and did not significantly reduce mites in one trial, but reduced mite counts to zero after 4 wk in trial 2. Permethrin strips had no effect on mite populations. This may have been due to mite resistance, even though this mite population had not been exposed to pyrethroids for several years. Sulfur bags should be effective in caged or cage-free systems. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

    Science.gov (United States)

    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.

  8. House dust mites as potential carriers for IgE sensitization to bacterial antigens.

    Science.gov (United States)

    Dzoro, S; Mittermann, I; Resch-Marat, Y; Vrtala, S; Nehr, M; Hirschl, A M; Wikberg, G; Lundeberg, L; Johansson, C; Scheynius, A; Valenta, R

    2017-07-25

    IgE reactivity to antigens from Gram-positive and Gram-negative bacteria is common in patients suffering from respiratory and skin manifestations of allergy, but the routes and mechanisms of sensitization are not fully understood. The analysis of the genome, transcriptome and microbiome of house dust mites (HDM) has shown that Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) species are abundant bacteria within the HDM microbiome. Therefore, our aim was to investigate whether HDM are carriers of bacterial antigens leading to IgE sensitization in patients suffering from atopic dermatitis. Plasma samples from patients with AD (n = 179) were analysed for IgE reactivity to a comprehensive panel of microarrayed HDM allergen molecules and to S. aureus and E. coli by IgE immunoblotting. Antibodies specific for S. aureus and E. coli antigens were tested for reactivity to nitrocellulose-blotted extract from purified HDM bodies, and the IgE-reactive antigens were detected by IgE immunoblot inhibition experiments. IgE antibodies directed to bacterial antigens in HDM were quantified by IgE ImmunoCAP™ inhibition experiments. IgE reactivity to bacterial antigens was significantly more frequent in patients with AD sensitized to HDM than in AD patients without HDM sensitization. S. aureus and E. coli antigens were detected in immune-blotted HDM extract, and the presence of IgE-reactive antigens in HDM was demonstrated by qualitative and quantitative IgE inhibition experiments. House dust mites (HDM) may serve as carriers of bacteria responsible for the induction of IgE sensitization to microbial antigens. © 2017 The Authors. Allergy Published by John Wiley & Sons Ltd.

  9. Poor sleep is highly associated with house dust mite allergic rhinitis in adults and children.

    Science.gov (United States)

    Leger, Damien; Bonnefoy, Bénédicte; Pigearias, Bernard; de La Giclais, Bertrand; Chartier, Antoine

    2017-01-01

    Sleep disorders are often underreported to physicians by patients with allergies. This study aimed to characterize the sleep disorders associated with respiratory allergy to house dust mites (HDM) at the time of initiation of sublingual allergen immunotherapy (SLIT) in routine clinical practice. This prospective, cross-sectional, observational study was conducted between November 2014 and March 2015 at 189 French trial sites and included 1750 participants suffering from HDM allergy who were initiating SLIT. Participants aged less than 5 years old and those who had previously started an allergen immunotherapy (AIT) for HDM allergy were not enrolled in the study. Sleep disorders were assessed by self-administered questionnaires: the Epworth Sleepiness Scale (ESS), the Insomnia Severity Index (ISI) and a modified version of the Hotel Dieu-42 (HD-42) sleep disorder questionnaire. Logistic regression models adjusted for obesity, smoking status, asthma control and nasal obstruction were used to study the relationship between allergic rhinitis (AR) classification and sleep disorders/complaints. Of the 1786 participants enrolled, 1750 (907 adults and 843 children) composed the analysis population. The majority of participants (73.5% of adults and 65.8% of children) reported that their sleep disorders had prompted them to consult their physician. The most commonly observed sleep complaints were poor-quality sleep (50.3% of adults and 37.3% of children), snoring (48.1 and 41.4%, respectively) and nocturnal awakening (37.6 and 28.2%, respectively). Difficulties falling asleep were reported by 27.0% of adults and 24.7% of children. Adults and children suffering from severe persistent AR experienced sleep complaints significantly more often than participants with intermittent or mild persistent AR. This study highlights the high frequency of sleep disorders and their significant impact on patients with AR induced by HDM, in particular when AR is persistent and severe

  10. Effect of a commercial air ionizer on dust mites Dermatophagoides pteronyssinus and Dermatophagoides farinae (Acari:Pyroglyphidae) in the laboratory

    Institute of Scientific and Technical Information of China (English)

    Suhaili Zainal Abidin; Ho Tze Ming

    2012-01-01

    Objective:To investigate the short and long term efficacy of a commercial air ionizer in killing Dermatophagoides pteronyssinus (D. pteronyssinus) and Dermatophagoides farinae (D. farinae) mites. Methods: The effect of a commercial ionizer on D. pteronyssinus and D. farinae was evaluated in the laboratory, using a specially designed test. Mortality was assessed after 6, 16 and 24 hours for direct exposure and after 24, 36, 48, 60 and 72 hours for exposure in simulated mattress. New batches of mites were used for each exposure time. Results: LT50 for direct exposure of ionizer was 10 hours for D. pteronyssinus and 18 hours for D. farinae. The LT50 for exposure in simulated mattress was 132 hours or 5.5 days for D. pteronyssinus and 72 hours or 3 days for D. farinae. LT95 for direct exposure of ionizer was 36 hours for D. pteronyssinus and D. farinae. Meanwhile, the LT95 for exposure in simulated mattress was 956 hours or 39.8 days for D. pteronyssinus and 403 hours or 16.8 days for D. farinae. Conclusions:This study demonstrates the increasing mite mortalities with increasing exposure time of a commercial ionizer and suggests that negative ions produced by an ionizer kill dust mites and can be used to reduce natural mite populations on exposed surfaces such as floors, clothes, curtains, etc. However, there is reduced efficacy on mites inside stuffed materials as in mattresses and furniture.

  11. Unlocking the allergenic structure of the major house dust mite allergen der f 2 by elimination of key intramolecular interactions.

    Science.gov (United States)

    Takai, T; Ichikawa, S; Yokota, T; Hatanaka, H; Inagaki, F; Okumura, Y

    2000-11-03

    We report on the structural background of the remarkable reduction of allergenicity in engineering of the major house dust mite allergen Der f 2. Disruption of intramolecular disulfide bonds in Der f 2 caused extensive conformational change that was monitored by circular dichroism and gel-filtration analysis. The degree of conformational change correlated well with the degree of reductions in the capacity to bind IgE and to induce histamine release from basophils in mite-allergic patients. Loosening the rigid tertiary structure by elimination of key intramolecular interactions is an effective strategy to reduce the number of high affinity IgE epitopes of allergen vaccine.

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

    Science.gov (United States)

    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

  13. OZONE: ALTERNATIVE METHOD FOR MITE CONTROL ON SPECK

    Directory of Open Access Journals (Sweden)

    C. Cantoni

    2013-02-01

    Full Text Available This study is aimed at the development of a method for integrated mite control in the industrial production of speck. The investigation were carried out on the premises of five factories in the north-east of Italy. Tyrophagus putrescentiae and T. longior were predominant. The gaseous ozone treatment at low level (0.4 ppm was able to kill mites in a period within 15 days and 1 month. The characteristic layer of mould on the product surface reappears within 1 month from the end of treatment with ozone.

  14. Distribution and abundance of house dust mites, Dermatophagoides spp., in different ecological localities in Esna City, Kena Governorate, Egypt.

    Science.gov (United States)

    Yassin, M K; Rifaat, M M

    1997-08-01

    The distribution and abundance of house dust mites, Dermatophagoides spp. were studied in July, September and November, 1995 in three different localities in Esna City, Kena Governorate, Upper Egypt. During these months, 15 houses were sampled in each locality. 87% of riverside houses were infested with mites where D. pteronyssinus dominated (80%) over D. farinae. Sixty percent of the valley houses sampled were infested, where D. farinae was dominant (66%). Densities of both Dermatophagoides spp., were considerably higher in riverside than in valley houses. Live mites were not found in the lightly infested houses sampled in the desert area (54% positive). Relative humidity, which varied in houses located in different climatic localities in Esna City, was noted to be the principal limiting factor influencing the distribution and abundance of both species. Temperature did not appear to be an important factor influencing the distribution and abundance.

  15. Influence of house dust mite impermeable covers on health-related quality of life of adult patients with asthma: results of a randomized clinical trial.

    Science.gov (United States)

    van den Bemt, Lisette; de Vries, Marjolein P; Cloosterman, Sonja; Thoonen, Bart; Muris, Jean W M; Goossens, Marielle; Wesseling, Geertjan; van Schayck, Constant P

    2007-12-01

    The aim of this study was to evaluate the effect of house dust mite impermeable covers on asthma-specific health-related quality of life in adult asthmatic patients that were trained in guided self-management. In a 2-year randomized placebo-controlled clinical trial, information on the quality of life was collected. The improvement of Mini Asthma Quality of Life Questionnaire (AQLQ) score in the allergens-avoidance group (0.26) was comparable to the improvement in the placebo group (0.30) and not significant. HDM-impermeable covers for pillows, duvets, and mattresses did not result in improved health-related quality of life.

  16. 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.

    Science.gov (United States)

    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 (pallergy 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 (pallergies were common and independently associated with asthma, airway symptoms and rhinitis. Der f 1 allergen can be a risk factor for daytime breathlessness.

  17. Reduction of the in vivo allergenicity of Der p 2, the major house-dust mite allergen, by genetic engineering.

    Science.gov (United States)

    Chen, Kuan-Wei; Fuchs, Gudrun; Sonneck, Karoline; Gieras, Anna; Swoboda, Ines; Douladiris, Nikolas; Linhart, Birgit; Jankovic, Marija; Pavkov, Tea; Keller, Walter; Papadopoulos, Nikolaos G; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

    2008-05-01

    The major allergen of the house-dust mite Dermatophagoides pteronyssinus, Der p 2, is recognized by approximately 90% of mite-allergic patients. We have produced two recombinant fragments of Der p 2 comprising aa 1-53 and aa 54-129 and a hybrid molecule (aa 54-129+1-53), combining the two fragments in inverse order, by genetic engineering. The recombinant Der p 2 derivatives were expressed in E. coli and purified to homogeneity. rDer p 2 derivatives (fragments and hybrid) showed a considerably reduced beta sheet structure and IgE reactivity compared to the Der p 2 wild-type allergen. The allergenic activity of the Der p 2 derivatives was reduced more than tenfold as evaluated in vitro in basophil activation assays and in vivo by skin prick testing of mite-allergic patients. Immunization of mice and rabbits with rDer p 2 derivatives induced Der p 2-specific IgG antibodies, which inhibited the binding of allergic patients' IgE to Der p 2. Immunization of mice with rDer p 2 derivatives induced less allergenic IgE responses than immunization with rDer p 2. Thus the rDer p 2 derivatives exhibited less in vivo allergenic activity and allergenicity than the Der p 2 allergen but preserved immunogenicity and may hence represent candidates for specific immunotherapy of house-dust mite allergy.

  18. The efficacy of sublingual immunotherapy for house dust mites respiratory allergy: results of a GA2LEN meta-analysis.

    Science.gov (United States)

    Compalati, E; Passalacqua, G; Bonini, M; Canonica, G W

    2009-11-01

    Recent meta-analyses documented the efficacy and safety of sublingual immunotherapy (SLIT) in patients with allergic rhinitis (AR) and asthma (AA). Although SLIT appeared globally effective, the sub-analyses for single allergens provided uncertain results. This study is aimed to investigate the efficacy of SLIT with house dust mite (HDM) extracts in AR and AA through an updated reassessment of randomized controlled trials. Electronic databases were searched up to March 31, 2008, for randomized DBPC trials, assessing the efficacy of SLIT in AR and AA due to HDM sensitization. Outcomes were symptom scores and rescue medications use. For AR, eight studies fulfilled the selection criteria. A significant reduction in symptoms of AR (SMD -0.95; CI 95%-1.77 to -0.14 P = 0.02) was found in 194 patients (adults and children) receiving SLIT compared to 188 receiving placebo. For AA, with nine studies, similar results were found for symptoms (SMD -0.95; CI 95%-1.74 to -0.15 P = 0.02) in 243 patients (adults and children) receiving SLIT compared to 209 receiving placebo. A reduction in rescue medication use was found for AR (SMD -1.88; CI 95%-3.65 to -0.12 P = 0.04) in 89 patients, and AA (SMD -1.48; CI 95%-2.70 to -0.26 P = 0.02) in 202 patients. A relevant inter-study heterogeneity was detected. Promising evidence of efficacy for SLIT, using mite extract in allergic patients suffering from AR and AA, are herein shown. These findings suggest that more data are needed, derived from large-population-based high quality studies, and corroborated by objective outcomes, mainly for AA.

  19. HLA-DR polymorphism modulates response to house dust mites in a transgenic mouse model of airway inflammation.

    Science.gov (United States)

    Rajagopalan, G; Tilahun, A Y; Iijima, K; David, C S; Kita, H; Juhn, Y J

    2011-06-01

    We and others have reported that HLA-DRB1*03 is associated with childhood asthma. To extend this observation and to prove this association, we sensitized and challenged either HLA-DR2 (HLA-DRB1*1502) or HLA-DR3 (HLA-DRB1*0301) transgenic mice with house-dust mite extract. Inflammatory cell counts and cytokine levels in the bronchoalveolar lavage (BAL) fluid between HLA-DR3 and DR2 mice were compared. HLA-DR3 transgenic mice had significantly elevated eosinophil counts, Interleukin-4 and Interleukin-13 levels in the BAL fluid but not interferron gamma-γ. Thus, our study suggests that HLA-DRB1*0301 plays an important role in mounting a Th2-predominant immune response to house dust mite and Th2-type inflammation in the lung. © 2011 John Wiley & Sons A/S.

  20. Immunization of rabbits with nematode Ascaris lumbricoides antigens induces antibodies cross-reactive to house dust mite Dermatophagoides farinae antigens.

    Science.gov (United States)

    Nakazawa, Takuya; Khan, Al Fazal; Yasueda, Hiroshi; Saito, Akemi; Fukutomi, Yuma; Takai, Toshiro; Zaman, Khalequz; Yunus, Md; Takeuchi, Haruko; Iwata, Tsutomu; Akiyama, Kazuo

    2013-01-01

    There are controversial reports on the relationship between helminthic infection and allergic diseases. Although IgE cross-reactivity between nematode Ascaris antigens and house dust-mite allergens in allergic patients have been reported, whether Ascaris or the mite is the primary sensitizer remains unknown. Here we found that immunization of naïve animals with Ascaris lumbricoides (Al) antigens induced production of antibodies cross-reactive to mite antigens from Dermatophagoides farinae (Df). Sera from Bangladeshi children showed IgE reactivity to Ascaris and mite extracts. IgG from rabbits immunized with Al extract exhibited reactivity to Df antigens. Treatment of the anti-Al antibody with Df antigen-coupled beads eliminated the reactivity to Df antigens. In immunoblot analysis, an approximately 100-kDa Df band was the most reactive to anti-Al IgG. The present study is the first step towards the establishment of animal models to study the relationship between Ascaris infection and mite-induced allergic diseases.

  1. Candidate predators for biological control of the poultry red mite Dermanyssus gallinae

    NARCIS (Netherlands)

    Lesna, Izabela; Wolfs, Peter; Faraji, Farid; Roy, Lise; Komdeur, Jan; Sabelis, Maurice W.

    2009-01-01

    The poultry red mite, Dermanyssus gallinae, is currently a significant pest in the poultry industry in Europe. Biological control by the introduction of predatory mites is one of the various options for controlling poultry red mites. Here, we present the first results of an attempt to identify poten

  2. [Ecological data on house dust mites in the city of Semipalatinsk].

    Science.gov (United States)

    Iagofarov, F F; Galikeev, Kh L

    1987-01-01

    Distribution of mites of the genus Dermatophagoides in flats of allergic patients depending on the type of the building structure, relative air humidity and season of the year was studied. The mites are most frequently encountered in houses of wood or adobe with high air humidity. Autumn is an optimum season for reproduction of mites.

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

    Science.gov (United States)

    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 food from the paper (P 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.

  4. Measurement of serum immunoglobulin E (IgE) specific for house dust mite antigens in normal cats and cats with allergic skin disease.

    Science.gov (United States)

    Taglinger, K; Helps, C R; Day, M J; Foster, A P

    2005-05-01

    The purpose of this study was to determine whether cats with allergic skin disease have significant concentrations of serum Immunoglobulin E (IgE) specific for antigens derived from the house dust mites (HDM) Dermatophagoides farinae (DF) and Dermatophagoides pteronyssinus (DP). Enzyme-linked immunosorbent assays (ELISA) were developed for this purpose. Binding of serum allergen-specific IgE was detected via the use of biotinylated Fc-epsilon receptor alpha chain protein (FcvarepsilonRIalpha). Following optimisation of the assay, serum samples from 59 cats with allergic skin disease and 54 clinically normal cats were screened. Results were expressed as ELISA units per ml (EU/ml) compared to a standard curve. Serological findings were correlated with the clinical presentation of affected cats. Cats with symptoms of feline allergic skin disease were grouped as follows: self-induced alopecia without lesions (group 1), papulocrusting dermatitis (group 2), eosinophilic granuloma complex (group 3), papular/ulcerative dermatitis of head and neck/facial dermatitis (group 4), and a combination of symptoms (group 5). Control normal cats comprised the final group (group 6). The Kruskal-Wallis test was used for statistical analysis. There was no significant difference between groups for DF- and DP-specific IgE concentrations with a p-value of 0.875 and 0.705, respectively. Although the FcvarepsilonRIalpha-based ELISA was able to detect house dust mite-specific feline IgE, the presence of this allergen-specific IgE correlates poorly with the presence of clinical manifestations of allergic skin disease. The results of this study question the clinical relevance of house dust mite-specific IgE in feline allergic skin disease.

  5. Allergic Responses Induced by a Fungal Biopesticide Metarhizium anisopliae and House Dust Mite Are Compared in a Mouse Model

    Directory of Open Access Journals (Sweden)

    Marsha D. W. Ward

    2011-01-01

    Full Text Available Biopesticides can be effective in controlling their target pest. However, research regarding allergenicity and asthma development is limited. We compared the ability of fungal biopesticide Metarhizium anisopliae (MACA and house dust mite (HDM extracts to induce allergic responses in BALB/c mice. The extracts were administered by intratracheal aspiration at doubling doses (2.5–80 g protein 4X over a four-week period. Three days after the last exposure, serum and bronchoalveolar lavage fluid (BALF were collected. The extracts' relative allergenicity was evaluated based on response robustness (lowest significant dose response compared to control (0 g. MACA induced a more robust serum total IgE response than HDM. However, in the antigen-specific IgE assay, a similar dose of both MACA and HDM was required to achieve the same response level. Our data suggest a threshold dose of MACA for allergy induction and that M. anisopliae may be similar to HDM in allergy induction potential.

  6. Failure of the mite-pathogenic fungus Neozygites tanajoae and the predatory mite Neoseiulus idaeus to control a population of the cassava green mite, Mononychellus tanajoa.

    Science.gov (United States)

    Elliot, Simon L; de Moraes, Gilberto J; Mumford, John D

    2008-12-01

    Monitoring of a population of the phytophagous cassava green mite, Mononychellus tanajoa (Bondar), and its natural enemies was undertaken in central Bahia, Brazil, in mid-1996. In spite of the presence of extremely high densities of the predatory phytoseiid mite Neoseiulus idaeus Denmark & Muma, the phytophagous mite population reached such high densities itself that there was total overexploitation of the cassava plants, leading to total leaf loss. Meanwhile, the mite-pathogenic fungus Neozygites tanajoae Delalibera, Humber & Hajek did not affect the M. tanajoa population in its growth phase as there was no inoculum present, even though we predict from a simple regression model that there was the potential for epizootics at that time. Soon after the M. tanajoa population crashed due to defoliation, there could have been an epizootic but there were simply no mite hosts to infect. These data demonstrate the ineffectiveness of one natural enemy (the predator) in terms of prey population regulation and demonstrate the importance of timing in the possible effectiveness of the other (the pathogen). For the pathogen, this probably explains its sporadic effect on host populations as previously reported. We conclude that the fungus is likely to be most useful as an adjunct to biological control with predatory mites other than N. idaeus.

  7. Silicas for control of the poultry red mite Dermanyssus gallinae

    OpenAIRE

    Maurer, Veronika; Perler, Erika

    2006-01-01

    Control of the poultry red mite Dermanyssus gallinae is a challenge for organic as well as conventional egg producers. In organic agriculture, control should be attempted by mechanically acting substances (e.g. oils or diatomaceous earth), before acaricides are applied. Diatomaceous earth (DE) without acaricides was at least as effective as DE supplemented with pyrethrum or essential oils and a liquid formulation of silica in vitro. In on farm experiments, DE was effective during a limited pe...

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

    Science.gov (United States)

    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.

  9. Sublingual immunotherapy for house dust mite allergy in Southeast Asian children.

    Science.gov (United States)

    Lee, Melissa; Lee, Bee Wah; Vichyanond, Pakit; Wang, Jiu-Yao; Bever, Hugo Van

    2013-09-01

    To determine the use and efficacy of sublingual immunotherapy (SLIT) for house dust mite (HDM) allergies in Southeast Asian children. Aliterature search was performed in Pubmed and the Asian Pacific Journal of Allergy and Immunology. We also evaluated the literature for similar studies performed in Asia. Clinical trials involving children that assess SLIT for HDM allergies in Southeast Asia and Asia. There are no published studies on the use of SLIT for HD Mallergies in Southeast Asian children. However, there are seven studies from Asia which show that there are discrepancies over the benefits of SLIT for HDM allergies in Asian children. Limitations in these studies include small sample sizes and short study periods. We cannot say with certainty what the impact of SLIT is on HDM allergies in Southeast Asian children due to the lack of data. The available studies performed in Asia have their limitations but are suggestive of the potential of SLIT for HDM allergies in Southeast Asian children. This review highlights that good quality clinical research in this area in the Southeast Asian setting is warranted.

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

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Steenberg, Tove

    2016-01-01

    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...

  11. p-Anisaldehyde: acaricidal component of Pimpinella anisum seed oil against the house dust mites Dermatophagoides farinae and Dermatophagoides pteronyssinus.

    Science.gov (United States)

    Lee, Hoi-Seon

    2004-03-01

    The acaricidal activity of anise seed oil-derived p-anisaldehyde and commercially available components of anise seed oil was examined against Dermatophagoides farinae and D. pteronyssinus and compared with those of the synthetic acaricides, benzyl benzoate and N,N-diethyl- m-toluamide (DEET). On the basis of LD 50 values, the compound most toxic to D. farinae adults was p-anisaldehyde (1.11 microg/cm2) followed by benzyl benzoate (9.32 microg/cm2), DEET (36.84 microg/cm2), 3-carene (42.10 microg/cm2), and estragol (43.23 microg/cm2). Against D. pteronyssinus adults, p-anisaldehyde (0.98 microg/cm2) was much more effective than benzyl benzoate (6.54 microg/cm2), DEET (17.79 microg/cm2), 3-carene (39.84 microg/cm 2), and estragol (40.11 microg/cm2). p-Anisaldehyde was about 8.4 and 6.7 times more toxic than benzyl benzoate against D. farinae and D. pteronyssinus adults, respectively. The results suggested that p-anisaldehyde may be useful as a lead compound for the development of new agents for the selective control of house dust mites.

  12. 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.

    Directory of Open Access Journals (Sweden)

    Fang Lee Lim

    Full Text Available 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.

  13. Gravimetric dust sampling for control purposes and occupational dust sampling.

    CSIR Research Space (South Africa)

    Unsted, AD

    1997-02-01

    Full Text Available Prior to the introduction of gravimetric dust sampling, konimeters had been used for dust sampling, which was largely for control purposes. Whether or not absolute results were achievable was not an issue since relative results were used to evaluate...

  14. Dust mite allergen, glutathione S-transferase, induces T cell immunoglobulin mucin domain-4 in dendritic cells to facilitate initiation of airway allergy.

    Science.gov (United States)

    Mo, L-H; Yang, L-T; Zeng, L; Xu, L-Z; Zhang, H-P; Li, L-J; Liu, J-Q; Xiao, X-J; Zheng, P-Y; Liu, Z-G; Yang, P-C

    2017-02-01

    Allergens from dust mites play a critical role in the pathogenesis of airway allergy. The mechanism by which dust mite allergens induce allergic diseases is not fully understood yet. This study tests a hypothesis that the eighth subtypes of Dermatophagoides farina allergen (Derf8) play an important role in the induction of airway allergy. The protein of Derf8 was synthesized via molecular cloning approach. Dendritic cells (DC) were stimulated with Derf8 in the culture, and then, the expression of T cell immunoglobulin mucin domain 4 (TIM4) in dendritic cells (DC) was analysed. The role of Derf8 in the induction of airway allergy was evaluated with a mouse model. Exposure to Derf8 markedly induced the TIM4 expression in DCs by modulating the chromatin at the TIM4 promoter locus. Derf8 played a critical role in the expansion of the T helper 2 response in the mouse airway via inducing DCs to produce TIM4. Administration with Derf8-depleted dust mite extracts (DME) inhibited the allergic inflammation and induced regulatory T cells in mice with airway allergy. Derf8 plays an important role in the initiation of dust mite allergy. Vaccination with Derf8-deficient DME is more efficient to inhibit the dust mite allergic inflammation than using wild DME. © 2016 John Wiley & Sons Ltd.

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

    Directory of Open Access Journals (Sweden)

    Vanholme Bartel

    2009-03-01

    Full Text Available Abstract 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

  16. Suppression of dust mite allergy by mucosal delivery of a hypoallergenic derivative in a mouse model.

    Science.gov (United States)

    Ai, Chunqing; Zhang, Qiuxiang; Ding, Junrong; Ren, Chengcheng; Wang, Gang; Liu, Xiaoming; Tian, Fengwei; Zhao, Jianxin; Zhang, Hao; Chen, Yong Q; Chen, Wei

    2015-05-01

    Allergic asthma caused by house dust mite (HDM) is becoming a public health problem. Specific immunotherapy is considered to be the only curative treatment, but it is always associated with IgE-mediated side effects in the therapy process. A few studies showed that the disruption of allergen IgE epitopes could reduce IgE reactivity and thus reduce allergenic activity. In this study, a hypoallergenic derivative of the major HDM allergen Der p2 was constructed by genetic engineering. This derivative was confirmed to have a considerably reduced IgE reactivity compared with Der p2. For its application in vivo, recombinant Lactococcus lactis (LL-DM) was engineered to deliver the Der p2 derivative to the intestinal mucosal surface. Oral administration of LL-DM significantly alleviated Der p2-induced airway inflammation, as shown by reduced inflammatory infiltration and a reduction in Th2 cytokines in bronchoalveolar lavage. This protective effect was associated with an up-regulation of specific IgG2a and a decrease in IL-4 level in the spleen which may affect specific IgE response. Moreover, the levels of regulatory T cells in the mesenteric lymph nodes and spleen were markedly increased in mice fed with LL-DM, suggesting that LL-DM can inhibit allergic responses via the induction of regulatory T cell. Our results indicate that the Der p2 derivative is a promising therapeutic molecule for specific immunotherapy and recombinant lactic acid bacteria could be developed as a promising treatment or prevention strategy for allergic diseases.

  17. Neonatal exposure to pneumococcal phosphorylcholine modulates the development of house dust mite allergy during adult life.

    Science.gov (United States)

    Patel, Preeyam S; Kearney, John F

    2015-06-15

    Currently, ∼20% of the global population suffers from an allergic disorder. Allergies and asthma occur at higher rates in developed and industrialized countries. It is clear that many human atopic diseases are initiated neonatally and herald more severe IgE-mediated disorders, including allergic asthma, which is driven by the priming of Th2 effector T cells. The hygiene hypothesis attempts to link the increased excessively sanitary conditions early in life to a default Th2 response and increasing allergic phenomena. Despite the substantial involvement of IgE Abs in such conditions, little attention has been paid to the effects of early microbial exposure on the B cell repertoire prior to the initiation of these diseases. In this study, we use Ab-binding assays to demonstrate that Streptococcus pneumoniae and house dust mite (HDM) bear similar phosphorylcholine (PC) epitopes. Neonatal C57BL/6 mice immunized with a PC-bearing pneumococcal vaccine expressed increased frequencies of PC-specific B cells in the lungs following sensitizing exposure to HDM as adults. Anti-PC IgM Abs in the lung decreased the interaction of HDM with pulmonary APCs and were affiliated with lowered allergy-associated cell infiltration into the lung, IgE production, development of airway hyperresponsiveness, and Th2 T cell priming. Thus, exposure of neonatal mice to PC-bearing pneumococci significantly reduced the development of HDM-induced allergic disease during adult life. Our findings demonstrate that B cells generated against conserved epitopes expressed by bacteria, encountered early in life, are also protective against the development of allergic disease during adult life. Copyright © 2015 by The American Association of Immunologists, Inc.

  18. Shifting of Immune Responsiveness to House Dust Mite by Influenza A Infection: Genomic Insights

    KAUST Repository

    Al-Garawi, A.

    2011-12-14

    Respiratory viral infections have been associated with an increased incidence of allergic asthma. However, the mechanisms by which respiratory infections facilitate allergic airway disease are incompletely understood.We previously showed that exposure to a low dose of house dust mite (HDM) resulted in enhanced HDM-mediated allergic airway inflammation, and, importantly, marked airway hyperreactivity only when allergen exposure occurred during an acute influenza A infection. In this study, we evaluated the impact of concurrent influenza infection and allergen exposure at the genomic level, using whole-genome micro-array. Our data showed that, in contrast to exposure to a low dose of HDM, influenza A infection led to a dramatic increase in gene expression, particularly of TLRs, C-type lectin receptors, several complement components, as well as FcεR1. Additionally, we observed increased expression of a number of genes encoding chemokines and cytokines associated with the recruitment of proinflammatory cells. Moreover, HDM exposure in the context of an influenza A infection resulted in the induction of unique genes, including calgranulin A (S100a8), an endogenous damage-associated molecular pattern and TLR4 agonist. In addition, we observed significantly increased expression of serum amyloid A (Saa3) and serine protease inhibitor 3n (Serpina3n). This study showed that influenza infection markedly increased the expression of multiple gene classes capable of sensing allergens and amplifying the ensuing immune-inflammatory response. We propose that influenza A infection primes the lung environment in such a way as to lower the threshold of allergen responsiveness, thus facilitating the emergence of a clinically significant allergic phenotype. Copyright © 2012 by The American Association of Immunologists, Inc.

  19. House dust mite allergen level and allergen sensitization as risk factors for asthma among student in Central Jakarta

    OpenAIRE

    2006-01-01

    This study is a community-based study to get an overview about House Dust Mite (HDM) allergen level, allergen sensitization as risk factors of asthma. This is a cross-sectional study on 3,840 students from 19 junior high schools, aged 13-14 years. All of the respondents filled out the International Study on Asthma and Allergy in Children (ISAAC) questionnaire. Of 3840 respondents, 288 (7.5%) were assigned to asthma group (experience wheezing during the last 12 months). The skin prick test was...

  20. Qualitative and quantitative assessment of mites (Acari in domiciliary dust in rural dwellings in the "Zona da Mata" region, Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Oliveira Aristeu José de

    2003-01-01

    Full Text Available From July to September, 2000 (winter, and from January to March, 2001 (summer, 30 dust samples were collected for each season, from beds of rural dwellings located in farms in the geographical area named "Zona da Mata", Minas Gerais, Brazil. After being sorted, the mites were identified and quantified. The prevalence of mites in the samples was 100%. 891 mites were found in winter (22.97%, and 2988 in summer (77.03%. In winter, Dermatophagoides pteronyssinus (Trouessart, 1897 was the most prevalent (55.00%, followed by Blomia tropicalis (Bronswijk, Cock & Oshima, 1973 (27.06%, Euroglyphus maynei (Cooreman, 1950 (8.85%, and predator mites from Cheyletidae family (8.07%. In summer, the most prevalent species was B. tropicalis (47.79%, followed by D. pteronyssinus (43.38%, Cheyletidae (6.87%, and E. maynei (1.28%. Few Dermatophagoides farinae (Hughes, 1961, Chortoglyphus arcuatus (Troupeau, 1879, and mites from Tarsonemidae and Cunaxidae families were found, the last two occurring only in summer. No mites from Acaridae family were found. The greatest number of immature forms found in summer suggested a greater breeding activity in this season. It was also noted that different building materials and varied cleaning routines may influence the population size of domiciliary dust mites.

  1. Effect of the house dust mite allergen Der p 1 on tryptase release from human mast cells.

    Science.gov (United States)

    Wang, D Q; Shen, Y Y; Xu, J H; Tang, H

    2016-07-14

    This study aimed to investigate the effects of the house dust mite allergen Der p 1 on the secretion of tryptase from the human mast cell line HMC-1. Flow cytometry was used to determine the expression levels of protease-activated receptor-2 (PAR2) on the surface of HMC-1 cells. HMC-1 cells were treated with Der p 1, SLIGRL-NH2 (PAR2 agonist), LRGILS-NH2 (control peptide for PAR2), or Der p 1 + FSLLRY (PAR2 antagonist), and the tryptase levels were measured using enzyme-linked immunosorbent assay. The biological functions of PAR2 were determined using the calcium green indicator, and intracellular calcium fluorescence intensity in the different groups (Der p 1, SLIGRL-NH2, LRGILS- NH2, Der p 1 + FSLLRY, tryptase, tryptase + FSLLRY, or cell culture medium) was detected by laser scanning confocal microscopy. The mast cells expressed PAR2 receptor on their surfaces. Der p 1 alone induced a significant release of intracellular calcium and tryptase in HMC-1 cells compared with the SLIGRL- NH2 treatment group and the control group. The combination of Der p 1 and FSLLRY partly inhibited intracellular calcium and tryptase release in HMC-1 cells compared with the Der p 1 treatment group. Moreover, tryptase induced a significant release of intracellular calcium in the HMC-1 cells. Der p 1 induced HMC-1 cell degranulation and the release of tryptase by activating the PAR2 receptor on the cell surfaces. Tryptase activated the PAR2 receptor and induced intracellular calcium release from the HMC-1 cells in a positive feedback loop.

  2. Natural biological control of pest mites in Brazilian sun coffee agroecosystems.

    Science.gov (United States)

    Teodoro, Adenir V; Sarmento, Renato A; Rêgo, Adriano S; da Graça S Maciel, Anilde

    2010-06-01

    Coffee is one of the leading commodities in tropical America. Although plantations are usually established under a canopy of trees in most producing countries in the region, Brazilian coffee is mostly produced under full sun conditions. Such simple, single-crop agroecosystems with intensive agrochemical inputs often suffer with pests like mites. Predatory mites of the family Phytoseiidae are the main natural enemies associated with pest mites in the field. However, these beneficial arthropods struggle to survive in intensive agroecosystems such as coffee monocultures due to unfavorable microclimatic conditions, widespread pesticide use, and lack of alternative food (pollen, nectar). Conservation biological control uses a range of management strategies to sustain and enhance populations of indigenous natural enemies such as predatory mites. We discuss here conservation biological control as a strategy to improve biological control of pest mites by native predatory mites in Brazilian coffee monocultures as well as some related patents.

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

    Directory of Open Access Journals (Sweden)

    Azima Laili Hanifah

    2011-10-01

    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.

  4. Dual oxidase 2 is essential for house dust mite-induced pro-inflammatory cytokine production in human keratinocytes.

    Science.gov (United States)

    Ko, Eunbi; Choi, Hyun; Park, Kkot-Nara; Park, Ju-Yearl; Lee, Tae Ryong; Shin, Dong Wook; Bae, Yun Soo

    2015-12-01

    House dust mites (HDMs) are known to trigger chronic inflammation through Toll-like receptors (TLRs) and their signalling cascades. In this study, we found that TLR2 ligation by HDMs induced the activation of dual oxidase 2 (Duox2) and nuclear factor-κB (NF-κB), leading to the production of pro-inflammatory cytokines in human keratinocytes. Stimulation of human keratinocytes with HDMs resulted in increases in interleukin-8 (IL-8) and chemokine (C-C motif) ligand 20 (CCL20) levels. However, pro-inflammatory cytokine production was abolished in keratinocytes transfected with TLR2 siRNA, indicating that HDM-induced cytokine production was mediated via TLR2 signalling. We also examined the function of Duox1/2 isozymes, which are primarily expressed in keratinocytes, in HDM-mediated pro-inflammatory cytokine production. Human keratinocytes transfected with control siRNA or Duox1 siRNA showed no inhibition of IL-8 or CCL20 production in response to HDMs, whereas the silencing of Duox2 expression resulted in a failure to induce cytokine production. Moreover, the phosphorylation and nuclear localization of RelA/p65, a component of NF-κB, were induced by HDMs in human keratinocytes. Transfection of human keratinocytes with TLR2 siRNA or Duox2 siRNA resulted in the complete abolishment of RelA/p65 nuclear localization in response to HDMs. Taken together, these results indicate that the HDM-dependent TLR2-Duox2 signalling axis indeed promotes NF-κB activation, which induces IL-8 and CCL20 production and mediates epidermal keratinocyte inflammation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Hypoallergenic Der p 1/Der p 2 combination vaccines for immunotherapy of house dust mite allergy.

    Science.gov (United States)

    Chen, Kuan-Wei; Blatt, Katharina; Thomas, Wayne R; Swoboda, Ines; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

    2012-08-01

    More than 50% of allergic patients have house dust mite (HDM) allergy. Group 1 and 2 allergens are the major HDM allergens. We sought to produce and perform preclinical characterization of a recombinant hypoallergenic combination vaccine for specific immunotherapy of HDM allergy. Synthetic genes coding for 2 hybrid proteins consisting of reassembled Der p 1 and Der p 2 fragments with (recombinant Der p 2 [rDer p 2]/1C) and without (rDer p 2/1S) cysteines were expressed in Escherichia coli and purified to homogeneity by means of affinity chromatography. Protein fold was determined by using circular dichroism analysis, allergenic activity was determined by testing IgE reactivity and using basophil activation assays, and the presence of T-cell epitopes was determined based on lymphoproliferation in allergic patients. Mice and rabbits were immunized to study the molecules' ability to induce an allergic response and whether they induce allergen-specific IgG capable of inhibiting allergic patients' IgE binding to the allergens, respectively. rDer p 2/1C and rDer p 2/1S were expressed in large amounts in E coli as soluble and folded proteins. Because of the lack of disulfide bonds, rDer p 2/1S did not form aggregates and was obtained as a monomeric protein, whereas rDer p 2/1C did form aggregates. Both hypoallergens lacked relevant IgE reactivity and had reduced ability to induce allergic inflammation and allergic responses but induced similar T-cell proliferation as the wild-type allergens. Immunization with the hypoallergens (rDer p 2/1S > rDer p 2/1C) induced IgG antibodies in rabbits that inhibited the IgE reactivity of patients with HDM allergy to Der p 1 and Der p 2. The preclinical characterization indicates that particularly rDer p 2/1S can be used as a safe hypoallergenic molecule for both tolerance and vaccination approaches to treat HDM allergy. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  6. Effect of house dust mite immunotherapy on interleukin-10-secreting regulatory T cells in asthmatic children

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; XIANG Li; LIU Yong-ge; WANG Yong-hong; SHEN Kun-ling

    2010-01-01

    Background Subcutaneous specific immunotherapy has been demonstrated to be capable of inducing T-cell regulatory response.Interleukin-10 (IL-10) plays a crucial role in inducing allergen-specific tolerance.However the reports of the changes of IL-10 in house dust mite (HDM)-specific immunotherapy were varied.The aim of this study was to evaluate the function of IL-10-secreting regulatory T cells in asthma children successfully treated with HDM immunotherapy.Methods Peripheral blood mononuclear cells (PBMCs) were isolated from 27 patients following 1.5--2 years of HDM-specific immunotherapy (SIT, SIT group) and from 27 matched treated asthmatic children allergic to HDM (asthmagroup).After 48 hours of in vitro stimulation with HDM extracts, IL-10-secreting regulatory T cells were measured by four colour flow cytometry.Sera were tested for allergen-specific IgG4 and IgE using the Immuno CAP 100 assay.Results PBMCs from children undergoing immunotherapy following HDM extracts stimuli produced significantly more IL-10 compared with the asthma group.The frequency of iTreg cells and aTreg cells increased in SIT group after HDM stimulation, while it was not affected in the asthma group.Among the iTreg cells and aTreg cells, the frequency of CD4+CD25-Foxp3-IL-10+ Treg cells increased the most which was 2 times higher than that in unstimulated cultures in SIT group.The levels of HDM-specific IgG4 of SIT group was significiently higher compared with asthma group, but there was no correlation of the levels of HDM-specific IgG4 and IL-10 secreting Treg cells.Conclusions HDM-specific immunotherapy can successfully upregulate the frequency of IL-10-secreting Treg cells.CD4+CD25-Foxp3-IL-10+ Treg cells may play a key role in inducing the immune tolerance in HDM-specific immunotherapy.

  7. Sero-prevalence study of IgE responses to allergens from Malaysian house dust (HDM) and storage mites (SM).

    Science.gov (United States)

    Chong, K T; Wong, S F; Mak, J W; Loh, L C; Ho, T M

    2015-09-01

    Allergens of Dermatophagoides and Blomia species are well-characterized but not for other species. This study was conducted to determine the prevalence of allergic sensitization to house dust (HDM) and storage mites (SM). One hundred adult subjects (aged ≥ 18) were recruited. The mite specific IgE of all allergic subjects were higher compared with healthy subjetcs despite being not statistically significant except for D. farinae and G. malaysiensis. The mean serum IgE levels against HDM and SM for allergic subjects were significantly higher compared with those in healthy subjects. They were mainly sensitized to Dermatophagoides farinae (35%) and Glycycometus malaysiensis (37%). Immunoblots revealed not all allergic subjects showed positive immuno-reactivity against the mites tested. Single or multiple bands were observed for different species. The subjects were commonly sensitized to Group 2 (9-12 kDa), 10 (38 kDa) and 18 (40-48 kDa) allergens. Twenty-one out of 60 allergic subjects were sensitized to either one or more species. The majority of them (71%) were sensitized to single species. The allergic subjects were mainly sensitized to D. pteronyssinus, followed by Tyrophagus putrecentiae and Aleuroglyphus ovatus. Seven were solely sensitized to HDM while 10 were solely sensitized to SM. Four subjects were sensitized to both. Pre-adsorption study revealed no cross-reactivity. There was difference between the prevalence and reactivity to allergens of HDM and SM in these subjects. Both ELISA and immunoblot did not correlate well but can complement each other in improving the detection of mite allergens to the species level.

  8. Enzymatic activities of allergen extracts from three species of dust mites and cockroaches commonly found in Korean home.

    Science.gov (United States)

    Jeong, Kyoung Yong; Kim, Chungryul; Yong, Tai-Soon

    2010-06-01

    Allergen extracts from dust mites and cockroaches commonly found in Korean homes were used to evaluate their enzymatic activity as they are believed to influence allergenicity. Allergen extracts were prepared from 3 dust mite species (Dermatophagoides farinae, D. pteronyssinus, and Tyrophagus putrescentiae) and 3 cockroach species (Blattella germanica, Periplaneta americana, and P. fuliginosa) maintained in the Korea National Arthropods of Medical Importance Resource Bank. Proteins were extracted in PBS after homogenization using liquid nitrogen. The activities of various enzymes were investigated using the API Zym system. No significant difference in phosphatase, lipase, or glycosidase activity was observed among the 6 allergen extracts, but much difference was observed in protease activity. Protease activity was assessed in more detail by gelatin zymography and the EnzChek assay. Extract from T. putrescentiae showed the highest protease activity, followed by those of the cockroach extracts. Extracts from D. farinae and D. pteronyssinus showed only weak protease activity. Gelatinolytic activity was detected mainly in a 30-kDa protein in D. farinae, a 28-kDa protein in D. pteronyssinus, a > 26-kDa protein in T. putrescentiae, a > 20-kDa protein in B. germanica, and a > 23-kDa protein in P. americana and P. fuliginosa. The information on various enzymatic activities obtained in this study may be useful for future studies. In particular, the strong protease activity found in cockroach extracts could contribute to sensitization to cockroach allergens, which is known to be associated with the development of asthma.

  9. Effect of Alpinia katsumadai Hayata on House Dust Mite-Induced Atopic Dermatitis in NC/Nga Mice

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    Hye-Sun Lim

    2012-01-01

    Full Text Available We evaluated the effects of Alpinia katsumadai Hayata (AKH, Zingiberaceae extract on the production of nitric oxide (NO and prostaglandin E2 (PGE2 in RAW 264.7 cells, thymus- and-activation-regulated chemokine (TARC/CCL17 in HaCaT cells, and histamine level in HMC-1 cells. In an in vivo experiment, atopic dermatitis was induced by topical application of house dust mites for 4 weeks, and the protective effects of AKH was investigated by measuring the severity of the skin reaction on the back and ears, and plasma levels of immunoglobulin E (IgE and histamine. AKH extract suppressed the production of NO and PGE2 in RAW 264.7 cells, TARC in HaCaT cells, and histamine in HMC-1 cells in a dose-dependent manner. In in vivo experiments, the severity of dermatitis, including erythema/hemorrhage, edema, erosion and scaling, and plasma levels of IgE, and histamine were lower in NC/Nga mice with atopic dermatitis, treated with AKH extract than in untreated mice. AKH extract reduced the histological manifestations of atopic dermatitis-like skin lesions such as erosion, hyperplasia of the epidermis and dermis, and inflammatory cell infiltration on the skin of the back and ear. These results suggest that AKH inhibits the development of house dust mite-induced atopic dermatitis in NC/Nga mice.

  10. 159 Therapeutic Effect and Safety of the Sublingual Immunotherapy With Tropical House Dust Mite Allergen Vaccines in Asthmatic Cuban Adult Patients

    Science.gov (United States)

    Castro Almarales, Raúl Lázaro; Ronquillo, Mercedes; Labrada, Alexis; Castello, Mirta Alvarez; González, Mayda; Rodríguez, José; Enriquez, Irene; Navarro Viltres, Bárbara I; DíazLic, Yunia Oliva; Mateo, Maytee

    2012-01-01

    Background Subcutaneous injection route (SCIT) is burdened with the risk of severe adverse events; therefore, sublingual immunotherapy (SLIT) is being increasingly investigated. The efficacy of SLIT in asthma has been reviewed in a Cochrane meta-analysis. Allergic sensitization to Dermatophagoides pteronyssinus (Dp), Dermatophagoides siboney (Ds) and Blomia tropicalis (Bt) is strongly linked to respiratory allergy and asthma in Cuba (3). These last 2 species are relevant in tropical countries or even only in the Caribbean region (4). Nevertheless, well conducted clinical studies of immunotherapy with standardized allergen vaccines of these particular species are very scarce. Objective This study was conducted to assess the therapeutic effect and safety of allergen therapeutic vaccines of Dermatophagoides pteronyssinus, Dermatophagoides siboney and Blomia tropicalis House-Dust mites (VALERGEN, BIOCEN, Cuba) by sublingual route, in asthmatic patients. Methods Three Double-Blind Placebo-Controlled clinical trials were performed in 40 patients each, showing asthmatic symptoms and positive predominant Skin Prick Test (SPT) to each mite, respectively. Half of subjects were randomized to active group. Treatment consisted of sublingual drops with increasing daily doses for 3 weeks and maintenance doses (2000 BU) twice a week until 12 months. Results Therapeutic effect was assessed after 6 and 12 months using symptoms/medication diary cards, peak expiratory flow (PEF) measures and skin sensitivity to investigated mites. Adverse reactions were classified using the World Allergy Organization scale. The treatment reduced significantly (P < 0.01) clinical symptoms (38%, 95% CI, 33-44) and medication intake (26%, 95% CI, 21-32) with respect to placebo. The skin sensitivity to the allergens decreased also significantly (P < 0.01). The allergen amount needed to induce a positive SPT increased 52-fold. PEF variability decreased also significantly (P < 0.05). The treatment was

  11. Specific IgE, IgG and IgG4 antibodies against house dust mite in patients with bronchial asthma.

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    Okazaki,Morihiro

    1991-08-01

    Full Text Available Serum levels of total IgE, specific IgE, IgG and IgG4 against house dust mite were measured in mite-sensitive asthma patients receiving immunotherapy with house dust. Serum levels of total IgE, mite specific IgE and IgG did not significantly change during the course of hyposensitization. Increased levels of mite specific IgG4 were observed in patients during immunotherapy. The increase in specific IgG4 was dependent on the total dose of house dust administered in both children (r = 0.636, p less than 0.001 and adults (r = 0.629, p less than 0.01. However, the increase of specific IgG4 in adults was not as apparent as in children. These results might suggest that mite specific IgG4 is a useful immunological marker in the immunotherapy for allergic asthma, and that IgG4 antibody acts as a blocking antibody in atopic bronchial asthma.

  12. The wet method as one of the methods of investigation of house dust to identify the allergen mites

    Directory of Open Access Journals (Sweden)

    Людмила Вікторівна Газзаві-Рогозіна

    2015-05-01

    Full Text Available Aim. From the second half of the twentieth age there is gradual growth of distribution of allergic diseases. Approximately every fifth habitant has one or another displays of allergy. In addition, for the last decades displacement of beginning of allergic displays is marked on more early age, and increase of number of heavy clinical displays of disease.Methods. With the purpose of help specialists with unmedical education to the entomologists, parasitologists and to the assistants-parasitologists of regional (district and city laboratory centers of sanitary-epidemiology service, to the listeners of medical academies of post-graduate education this method of finding of allergen mites was developed.The wet method of dust selection, which is offered by us, is not only simple and accessible in the use, not requiring economic expenses but also allows to conduct the high-quality monitoring after the state of contamination of the different particles of environment.Result. Kharkov regional Sanitary & Epidemiological Service does more than 5 years of dust researches by this method. These researches were successfully conducted in the presence of dustborne mites. On the basis of these results the patent of Ukraine is got on an invention: Patent № 60763 UA, MPK A61V10 / 00 [9], this method is in detail described in a train aid, which was ratified scientific advice of the Kharkov medical academy of post-graduate education in 2012. «Mines of domestic dust. Distributions. Ways of discovery. Рrophylaxis»Conclusions. By the wet method of selection of domestic dust, even in barbershops, where a minimum of soft inventory, and the working tool of masters-hairdressers (masters of manicure washes and disinfected, positive finds come to light. As compared to a selection and research of dry tests of dust, a wet method is more effective and high-quality yet and because a wet brush does not enable dust, and to the present of mines in it, to fly away at a selection

  13. Proteome, Allergenome, and Novel Allergens of House Dust Mite, Dermatophagoides farinae.

    Science.gov (United States)

    Choopong, Jintarat; Reamtong, Onrapak; Sookrung, Nitat; Seesuay, Watee; Indrawattana, Nitaya; Sakolvaree, Yuwaporn; Chaicumpa, Wanpen; Tungtrongchitr, Anchalee

    2016-02-05

    Dermatophagoides farinae mite is a predominant source of indoor allergens causing high incidence of allergy worldwide. People with different genetic background respond differently to the mite components, and thus the component-resolved diagnosis (CRD) is preferred to the conventional allergy test based on crude mite extract. In this study, proteome and culprit components in the D. farinae whole body extract that sensitized the allergic patients were studied by using SDS-PAGE (1DE) and 2DE-IgE immunoblotting followed by LC-MS/MS and database search for protein identification. From the 1DE, the mite extract revealed 105 proteins that could be classified into seven functionally different groups: allergens, structural components, enzymes, enzyme inhibitor, receptor proteins, transporters, and binding/regulatory/cell signaling proteins. From the 2DE, the mite extract produced 94 spots; 63 were bound by IgE in sera of 20 D. farinae allergic patients. One more protein that was not revealed by the 2DE and protein staining reacted with IgE in 2 allergic patients. Proteins in 40 spots could be identified as 35 different types. Three of them reacted to IgE of >50% of the allergic patients, and hence they are major allergens: tropomyosin or Der f 10 (75%), aconitate hydratase (70%), and one uncharacterized protein (55%). Aconitate hydratase is a novel D. farinae major allergen unraveled in this study. Several mite minor allergens that have never been previously reported are also identified. The data have clinical applications in the component-resolved diagnosis for tailor-designed allergen-specific immunotherapy.

  14. 30 CFR 56.9315 - Dust control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Dust control. 56.9315 Section 56.9315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... control. Dust shall be controlled at muck piles, material transfer points, crushers, and on haulage...

  15. CHARACTERIZATION OF IMMEDIATE AND LATE PHASE AIRWAY RESPONSES TO HOUSE DUST MITE CHALLENGE IN BROWN NORWAY RATS AND CORRELATIONS AMONG PHYSIOLOGICAL MEDIATORS

    Science.gov (United States)

    CHARACTERIZATION OF IMMEDIATE AND LATE PHASE AIRWAY RESPONSES TO HOUSE DUST MITE CHALLENGE IN BROWN NORWAY RATS AND CORRELATIONS AMONG PATHOPHYSIOLOGICAL MEDIATORS (P.SinghI, D.W. Winsett2, M.J. Daniels2, J. Richards2, K. Crissman2, D.L. Doerfler2 and M.I. Gilmour2, 1NCSU, Ra...

  16. Digesting the role of specific pre- and synbiotics in the prevention of house dust mite asthma : Thinking out of the lung

    NARCIS (Netherlands)

    Verheijden, K.A.T.

    2015-01-01

    According to the World Health Organization (WHO) asthma is a chronic disease affecting 235 million people worldwide. The disease is characterized by airway inflammation, airway hyperresponsiveness and airway narrowing. House dust mites (HDM) are common allergens that can induce allergic diseases lik

  17. Impermeable dust mite covers in the primary and tertiary prevention of allergic disease: a meta-analysis.

    Science.gov (United States)

    Arroyave, Whitney D; Rabito, Felicia A; Carlson, John C; Friedman, Eleanor E; Stinebaugh, Sarah J

    2014-03-01

    Up to 40% of the world's population has been diagnosed with an allergic disease. The most prevalent allergy is to house dust mites. Impermeable mattress covers are often the first treatment in the prevention and decrease of symptoms of allergic disease. To perform a meta-analysis evaluating the effectiveness of impermeable mattress covers in the primary prevention of allergic disease and as a single intervention in the tertiary prevention of allergic disease symptoms. MEDLINE, Embase, Web of Science, and CINAHL were systematically searched for relevant publications. Seven primary prevention trials (n = 3,461) and 17 tertiary prevention trials (n = 1,671) met the inclusion criteria and were included in the review. All article reviews and abstractions were performed in duplicate. No significant pooled relative risks were found for the prevention of allergic disease. The pooled relative risks were 0.97 (95% confidence interval [CI] 0.62-1.51) for house dust mite sensitization, 0.92 (95% CI 0.81-1.05) for wheeze, 0.85 (95% CI 0.70-1.02) for asthma, 1.03 (95% CI 0.90-1.19) for allergic rhinitis, and 1.05 (95% CI 0.84-1.32) for allergic dermatitis. Likewise, no significant pooled standardized mean differences were found in the tertiary prevention of symptoms. The pooled standardized mean differences were -0.03 (95% CI -0.15 to 0.09) for peak flow, -0.06 (95% CI -0.32 to 0.20) for asthma symptom score, and -0.39 (95% CI -0.88 to 0.11) for nasal symptom score. A significant effect was seen in the decrease of house mite dust level in the mattress (-0.79, 95% CI -0.98 to -0.60). No evidence was found to support the use of impermeable mattress covers in the primary prevention of allergic disease or in the tertiary prevention of allergic disease symptoms. Copyright © 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  18. Size of predatory mites and refuge entrance determine success of biological control of the coconut mite

    NARCIS (Netherlands)

    da Silva, F.R.; de Moraes, G.J.; Lesna, I.; Sato, Y.; Vasquez, C.; Hanna, R.; Sabelis, M.W.; Janssen, A.

    2016-01-01

    Predators face the challenge of accessing prey that live in sheltered habitats. The coconut mite Aceriaguerreronis Keifer (Acari: Eriophyidae) lives hidden beneath the perianth, which is appressed to the coconut fruit surface, where they feed on the meristematic tissue. Its natural enemy, the predat

  19. Domestic mite antigens in floor and airborne dust at workplaces in comparison to living areas: a new immunoassay to assess personal airborne allergen exposure.

    Directory of Open Access Journals (Sweden)

    Ingrid Sander

    Full Text Available OBJECTIVES: Allergens produced by domestic mites (DM are among the most common allergic sensitizers and risk factors for asthma. To compare exposure levels between workplaces and living areas a new assay able to measure airborne DM antigen concentrations was developed. METHODS: At workplaces and in living areas, 213 floor dust samples and 92 personal inhalable dust samples were collected. For sensitive quantification of DM antigens, a new enzyme immunoassay (EIA based on polyclonal antibodies to Dermatophagoides farinae extract was developed. Reactivity of five house dust mite and four storage mite species was tested. All dust samples were tested with the new EIA and with the Der f 1 and Der p 1-EIAs (Indoor Biotechnologies, UK which detect major allergens from D. farinae and D. pteronyssinus by monoclonal antibodies. Samples below the detection limit in the DM-EIA were retested in an assay variant with a fluorogenic substrate (DM-FEIA. RESULTS: The newly developed DM-EIA detects antigens from all nine tested domestic mite species. It has a lower detection limit of 200 pg/ml of D.farinae protein, compared to 50 pg/ml for the DM-FEIA. DM antigens were detected by DM-EIA/FEIA in all floor dust and 80 (87% of airborne samples. Der f 1 was found in 133 (62% floor dust and in only 6 airborne samples, Der p 1 was found in 70 (33% of floor samples and in one airborne sample. Der f 1 and DM concentrations were highly correlated. DM-antigens were significantly higher in inhalable airborne samples from textile recycling, bed feather filling, feed production, grain storage and cattle stables in comparison to living areas. CONCLUSIONS: A new sensitive EIA directed at DM antigens was developed. DM antigen quantities were well correlated to Der f 1 values and were measurable in the majority (87% of airborne dust samples. Some workplaces had significantly higher DM antigen concentrations than living areas.

  20. Ex-ante analysis of economic returns from biological control of coconut mite in Tanzania

    NARCIS (Netherlands)

    Oleke, J.M.; Manyong, V.; Mignouna, D.; Isinika, A.; Mutabazi, K.; Hanna, R.; Sabelis, M.

    2013-01-01

    The coconut mite, Aceria guerreronis Keifer, has been identified as one of the pests that pose a threat to the coconut industry in Benin. The study presents the simulation results of the economic benefits of the biological control of coconut mites in Benin using a standard economic surplus model. In

  1. Indoor pollutant hexabromocyclododecane enhances house dust mite-induced activation of human monocyte-derived dendritic cells.

    Science.gov (United States)

    Canbaz, Derya; Lebre, M Cristina; Logiantara, Adrian; van Ree, Ronald; van Rijt, Leonie S

    2016-11-01

    The indoor pollutant hexabromocyclododecane (HBCD) has been added as flame retardant to many consumer products but detaches and accumulates in house dust. Inhalation of house dust leads to exposure to house dust mite (HDM) allergens in the presence of HBCD. Activation of dendritic cells is crucial in the sensitization to HDM allergens. The current study examined whether exposure to HBCD affected activation/maturation of HDM-exposed human dendritic cells (DC). Human monocyte-derived DC (moDC) were exposed simultaneously to HDM and a concentration range of HBCD (0.1-20 μM) in vitro. HDM exposure of moDC induced expression of co-stimulatory molecule CD80 and production of pro-inflammatory cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α. However, simultaneous exposure of moDC to HBCD and HDM enhanced the expression of antigen presenting molecule HLA-DR, co-stimulatory molecule CD86 and pro-inflammatory cytokine IL-8 depending on the dose of HBCD. Our results indicate that simultaneous exposure of HDM and HBCD can enhance the antigen presentation and maturation/activation of DC.

  2. Savings associated with high-dose hypoallergenic house dust mite immunotherapy in rhinitis and/or asthma patients in Spain

    Science.gov (United States)

    García Robaina, José Carlos; Polanco Sánchez, Carlos; Estella Pérez, Elvira

    2016-01-01

    Objectives To quantify the cost difference between conventional symptomatic treatment of mite allergy and specific subcutaneous immunotherapy (SCIT). Methods Observational, retrospective, and multicenter study was carried out in Spain in 2013. The medical records of 419 patients diagnosed with rhinitis and/or bronchial asthma for mite allergy were retrieved. Mean age was 24.9 years (standard deviation 14.4). The use of symptomatic medication (rescue and daily), diagnostic tests, unscheduled medical care, and sick leave days associated with SCIT treatment versus no-SCIT treatment was compared. Also measured was the SCIT treatment to no-SCIT treatment costs ratio: used resources (symptomatic medication, unscheduled medical care, diagnostic tests, and 3 years SCIT treatment and sick leave days) were quantified in euros. Efficacy (decreased resource usage) of first-year treatment was assumed during the remaining 2 years and also during the 3-year follow-up period. Results After a single year of SCIT, all quantified resources diminished significantly (P<0.05) from baseline. Estimated reduction in cost items included hospital resources (100% in hospitalizations, 82% in visits to the allergist, and 79% in emergency room visits), therapies (56% in rescue medication and 63% in daily medication), diagnostic tests (77%), and sick leave days (94%). Ratio of comparative calculation described as SCIT treatment versus non-SCIT treatment (or conventional symptomatic treatment) is 0.8. Conclusion Direct costs are reduced by 64% and indirect costs by 94%. SCIT of hypoallergenic preparation of dust mite (Acaroid®) allows cost savings versus conventional treatment. Estimated savings for the public National Health System are 5.7 times the cost of immunotherapy. PMID:27366098

  3. Significance and control of the poultry red mite, Dermanyssus gallinae.

    Science.gov (United States)

    Sparagano, O A E; George, D R; Harrington, D W J; Giangaspero, A

    2014-01-01

    The poultry red mite, Dermanyssus gallinae, poses a significant threat to poultry production and hen health in many parts of the world. With D. gallinae increasingly suspected of being a disease vector, and reports indicating that attacks on alternative hosts, including humans, are becoming more common, the economic importance of this pest has increased greatly. As poultry production moves away from conventional cage systems in many parts of the world, D. gallinae is likely to become more abundant and difficult to control. Control remains dominated by the use of synthetic acaricides, although resistance and treatment failure are widely reported. Alternative control measures are emerging from research devoted to D. gallinae and its management. These alternative control measures are beginning to penetrate the market, although many remain at the precommercial stage. This review compiles the expanding body of research on D. gallinae and assesses options for its current and future control. We conclude that significant advances in D. gallinae control are most likely to come through an integrated approach adopting recent research into existing and novel control strategies; this is being combined with improved monitoring and modeling to better inform treatment interventions.

  4. Genetically engineered Lactococcus lactis protect against house dust mite allergy in a BALB/c mouse model.

    Directory of Open Access Journals (Sweden)

    Chunqing Ai

    Full Text Available Mucosal vaccine based on lactic acid bacteria is an attractive concept for the prevention and treatment of allergic diseases, but their mechanisms of action in vivo are poorly understood. Therefore, we sought to investigate how recombinant major dust mite allergen Der p2-expressing Lactococcus lactis as a mucosal vaccine induced the immune tolerance against house dust mite allergy in a mouse model.Three strains of recombinant L. lactis producing Der p2 in different cell components (extracellular, intracellular and cell wall were firstly constructed. Their prophylactic potential was evaluated in a Der p2-sensitised mouse model, and immunomodulation properties at the cellular level were determined by measuring cytokine production in vitro.Der p2 expressed in the different recombinant L. lactis strains was recognized by a polyclonal anti-Der p2 antibody. Oral treatment with the recombinant L. lactis prior sensitization significantly prevented the development of airway inflammation in the Der p2-sensitized mice, as determined by the attenuation of inflammatory cells infiltration in the lung tissues and decrease of Th2 cytokines IL-4 and IL-5 levels in bronchoalveolar lavage. In addition, the serum allergen-specific IgE levels were significantly reduced, and the levels of IL-4 in the spleen and mesenteric lymph nodes cell cultures were also markedly decreased upon allergen stimulation in the mice fed with the recombinant L. lactis strains. These protective effects correlated with a significant up-regulation of regulatory T cells in the mesenteric lymph nodes.Oral pretreatment with live recombinant L. lactis prevented the development of allergen-induced airway inflammation primarily by the induction of specific mucosal immune tolerance.

  5. Candidate predators for biological control of the poultry red mite Dermanyssus gallinae.

    Science.gov (United States)

    Lesna, Izabela; Wolfs, Peter; Faraji, Farid; Roy, Lise; Komdeur, Jan; Sabelis, Maurice W

    2009-06-01

    The poultry red mite, Dermanyssus gallinae, is currently a significant pest in the poultry industry in Europe. Biological control by the introduction of predatory mites is one of the various options for controlling poultry red mites. Here, we present the first results of an attempt to identify potential predators by surveying the mite fauna of European starling (Sturnus vulgaris) nests, by assessing their ability to feed on poultry red mites and by testing for their inability to extract blood from bird hosts, i.e., newly hatched, young starlings and chickens. Two genuine predators of poultry red mites are identified: Hypoaspis aculeifer and Androlaelaps casalis. A review of the literature shows that some authors suspected the latter species to parasitize on the blood of birds and mammals, but they did not provide experimental evidence for these feeding habits and/or overlooked published evidence showing the reverse. We advocate careful analysis of the trophic structure of arthropods inhabiting bird nests as a basis for identifying candidate predators for control of poultry red mites.

  6. Mites and allergy.

    Science.gov (United States)

    Fernández-Caldas, Enrique; Puerta, Leonardo; Caraballo, Luis

    2014-01-01

    Allergic diseases triggered by mite allergens include allergic rhinoconjunctivitis, asthma, atopic dermatitis and other skin diseases. Since the early discovery of the allergenic role of mites of the genus Dermatophagoides in the mid 1960s, numerous species have been described as the source of allergens capable of sensitizing and inducing allergic symptoms in sensitized and genetically predisposed individuals. The main sources of allergens in house dust worldwide are the fecal pellets of the mite species D. pteronyssinus, D. farinae, Euroglyphus maynei and the storage mites Blomia tropicalis, Lepidoglyphus destructor and Tyropahgus putrescentiae. Group 1 and 2 allergens are major house dust mite allergens. The main allergens in storage mites include fatty acid-binding proteins, tropomyosin and paramyosin homologues, apolipophorin-like proteins, α-tubulins and others, such as group 2, 5 and 7 allergens. Cross-reactivity is an important and common immunological feature among mites. Currently, purified native or recombinant allergens, epitope mapping, proteomic approaches and T cell proliferation techniques are being used to assess cross-reactivity. Mites contain potent enzymes capable of degrading a wide range of substrates. Most mite allergens are enzymes. Advances in genomics and molecular biology will improve our ability to understand the genetics of specific IgE responses to mites. Mite allergen avoidance and immunotherapy are the only two allergen-specific ways to treat mite-induced respiratory and cutaneous diseases. © 2014 S. Karger AG, Basel.

  7. on control of the spider mite (Tetranychus urticae Koch.) in peanut

    African Journals Online (AJOL)

    Samson Edoja

    2016-07-27

    Jul 27, 2016 ... spp. are mites that cause damage to several crops and are primarily controlled by synthetic pesticides. Literature showed that ... increase pesticide resistance of insect-pests (Gill and ... way less aggressive to the environment.

  8. Control of the sheep scab mite Psoroptes ovis in vivo and in vitro using fungal pathogens.

    Science.gov (United States)

    Abolins, S; Thind, B; Jackson, V; Luke, B; Moore, D; Wall, R; Taylor, M A

    2007-09-30

    As part of a research programme designed to identify biological agents for the control of sheep scab, the pathogenicity of the fungus Metarhizium anisopliae to Psoroptes mites in the presence of sheepskin and wool was examined in the laboratory. No inhibitory effects of skin and wool were observed and high levels of infection were recorded. Subsequently the pathogenicity of formulations of both M. anisopliae and Beauveria bassiana to Psoroptes ovis was studied in vivo. For this, 36 batches of 20 adult female Psoroptes mites were confined in 25 mm diameter chambers which were attached to the backs of 6 scab-naive sheep. In some treatments, mites were exposed to the fungal pathogens for 48 h in vitro prior to being placed on the host, while other treatments involved mites with no prior exposure placed directly onto the skin of a host treated with a fungal pathogen. After 48 h on the host, mites were removed, incubated individually and all fungal infections were recorded. Fungal infection was observed in all treatments, except untreated controls. However, B. bassiana infected a significantly greater number of mites than M. anisopliae with all the formulations examined. Infection rates were highest when mites were exposed to dry conidia (>90%) and lowest with M. anisopliae in diatomaceous earth. Overall, the infection rate was not affected by whether or not the mites were given prior exposure to the conidia, before being placed on the sheep. The results demonstrate that Psoroptes mites can become infected by entomopathogenic fungi on the skin of sheep and provides a first demonstration of the potential of this technology for the control of sheep scab.

  9. Savings associated with high-dose hypoallergenic house dust mite immunotherapy in rhinitis and/or asthma patients in Spain

    Directory of Open Access Journals (Sweden)

    García Robaina JC

    2016-06-01

    Full Text Available José Carlos García Robaina,1 Carlos Polanco Sánchez,2 Elvira Estella Pérez,2 1Allergy Department, University Hospital Nuestra Señora de Candelaria, Santa Cruz de Tenerife, 2Health Economics & Outcomes Research, Corporate Affairs, Merck S.L., Madrid, Spain Objectives: To quantify the cost difference between conventional symptomatic treatment of mite allergy and specific subcutaneous immunotherapy (SCIT. Methods: Observational, retrospective, and multicenter study was carried out in Spain in 2013. The medical records of 419 patients diagnosed with rhinitis and/or bronchial asthma for mite allergy were retrieved. Mean age was 24.9 years (standard deviation 14.4. The use of symptomatic medication (rescue and daily, diagnostic tests, unscheduled medical care, and sick leave days associated with SCIT treatment versus no-SCIT treatment was compared. Also measured was the SCIT treatment to no-SCIT treatment costs ratio: used resources (symptomatic medication, unscheduled medical care, diagnostic tests, and 3 years SCIT treatment and sick leave days were quantified in euros. Efficacy (decreased resource usage of first-year treatment was assumed during the remaining 2 years and also during the 3-year follow-up period. Results: After a single year of SCIT, all quantified resources diminished significantly (P<0.05 from baseline. Estimated reduction in cost items included hospital resources (100% in hospitalizations, 82% in visits to the allergist, and 79% in emergency room visits, therapies (56% in rescue medication and 63% in daily medication, diagnostic tests (77%, and sick leave days (94%. Ratio of comparative calculation described as SCIT treatment versus non-SCIT treatment (or conventional symptomatic treatment is 0.8. Conclusion: Direct costs are reduced by 64% and indirect costs by 94%. SCIT of hypoallergenic preparation of dust mite (Acaroid® allows cost savings versus conventional treatment. Estimated savings for the public National Health

  10. Prevalence of sensitivity to cockroach allergens and IgE crossreactivity between cockroach and house dust mite allergens in Chinese patients with allergic rhinitis and asthma

    Institute of Scientific and Technical Information of China (English)

    SUN Bao-qing; LAI Xu-xin; Birgitte Gjesing; Michael Dho Spangfort; ZHONG Nan-shan

    2010-01-01

    Background Cockroaches are an important indoor allergen source causing allergic rhinitis and asthma. The aim of this study was to investigate the cockroach prevalence in mainland of China and the cross-reactivity of IgE between cockroach and house dust mite allergen in Chinese patients.Methods The cockroach sensitization pattern was based on a skin prick test (SPT) obtained from a national multicenter prevalence study, in which 6304 patients from 25 allergy centers across China participated. Factors, including different regions of China, age, gender and the correlations between the American and German cockroaches and house dust mite Der p were investigated. Eighteen out of 1236 clinical sera from south China were selected to perform the cross-inhibition assay between house dust mites and cockroaches.Results Totally 25.7% of patients were SPT positive to the American cockroach (Periplaneta Americana, Per a) and 18.7% SPT positive to the German cockroach (Blattella germanica, Bla g). The prevalence of positive cockroach SPT was higher in southern than in northern China, higher in adults than in children, and higher in males than in females.Patients had relatively low levels of cockroach SPT reactions, mainly class 1 or 2. Of the SPT positive cockroach patients,88% were also SPT positive to house dust mite (Dermatophagoides pteronyssinus, Der p). An IgE cross-inhibition study confirmed that Der P sensitization could cause false positive SPT reactions against cockroach.Conclusions A relatively high prevalence of cockroach sensitivity was found in mainland of China. However, a cross-inhibition study showed that only a small number of patients appear to have Bla g and/or Per a as primary sensitizing source. The importance of cockroaches as a risk factor for sensitization and triggers of allergic symptoms in mainland of China needs to be further investigated.

  11. Protease-activated receptor-2 activation contributes to house dust mite-induced IgE responses in mice.

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    Sijranke Post

    Full Text Available 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

  12. mites y control constitucional en México

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    Arminda Balbuena Cisneros

    2007-01-01

    Full Text Available Los límites a la reforma constitucional es un tema siempre vigente en el derecho constitucional, ello es así por las posibles arbitrariedades que pueden cometer los órganos detentadores del poder mediante las modificaciones a la constitución. En México, hoy en día este tema cobra particular relevancia por el profundo proceso de reforma que se vive, y por la controvertida posición que la corte mexicana ha adoptado en relación con los límites a la reforma. El presente artículo trata de dar una visión general de los límites al poder de reforma y, en particular, de la posición que la suprema corte de justicia de la nación ha adoptado respecto a los mismos.

  13. The use of entomopathogenic fungi for the control of parasitic mites, Psoroptes spp.

    Science.gov (United States)

    Smith, K E; Wall, R; French, N P

    2000-09-20

    In vitro trials were carried out to evaluate the potential of fungal pathogens as biological control agents of parasitic mites, Psoroptes ovis (Hering) (Acari: Psoroptidae) from rabbit hosts (synonym: Psoroptes cuniculi). The fungus Hirsutella thompsonii Fisher showed no pathogenicity. Metarhizium anisopoliae (Metschinkoff), however, showed a high level of pathogenicity; 3 days after exposure to fungal conidia all mites were dead and 6 days after exposure 60% of the dead adult females, 10% of the dead adult males and 30% of the dead female nymphs had fungal hyphae protruding from their cuticular surface. There was a significant effect of conidial concentration on the number of mite cadavers that displayed fungal infection. Exposure to between 1x10(4) and 1x10(6) conidiaml(-1) resulted in 2-25% of the mites being infected. Mean infection levels were highest, 71%, when the mites were exposed to 1x10(7) conidiaml(-1). Similarly, there was a significant effect of conidial concentration on the time taken for the mites to reach 50% levels of mortality (LT(50)) The mean LT(50) value was approximately 2.7 days, when the mites were exposed to a solution of 1x10(7) and 1x10(8) conidiaml(-1) which was significantly shorter than controls exposed to 0.03% Tween-80 solution only. There was no significant effect of passaging the fungus, either once or twice, through the host on the subsequent infectivity of M. anisopliae. The potential for use of entornopathogenic fungi for the control of parasitic mites, particularly in relation to sheep, is discussed.

  14. Guideline recommendations on the use of allergen immunotherapy in house dust mite allergy: Time for a change?

    Science.gov (United States)

    Calderón, Moisés A; Bousquet, Jean; Canonica, G Walter; Cardell, Lars-Olaf; Fernandez de Rojas, Dolores Hernandez; Kleine-Tebbe, Jörg; Demoly, Pascal

    2017-07-01

    Guidelines on the treatment of asthma, allergic rhinitis (AR), and allergen immunotherapy (AIT) lack recommendations for house dust mite (HDM) allergy. An expert panel reviewed current guidelines in the light of new data to assess whether guidelines could be improved. Most guidelines and key position papers did not provide specific recommendations on treatment of allergic asthma (AA) caused by HDM allergy, although some included AIT as a treatment option for AA in general. Around half of the guidelines stated that AIT with HDM extract was an effective treatment for AR, with several indicating sublingual immunotherapy as an option. This heterogeneity is caused by quality issues affecting studies of AIT with perennial allergens in patients with AA and AR, including use of different diagnosis and severity criteria, lack of consistent scoring or grading systems for primary and safety outcomes, and lack of consensus on treatment parameters. There is a need for well-designed clinical trials to serve as a basis for guideline recommendations. Although results from recent studies strengthen the evidence base for the efficacy and safety of sublingual immunotherapy in patients with HDM-induced AA and AR, their effect on subsequent guideline updates will depend on the methodology and evidence model used by each guideline. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

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

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    Ying Lei

    Full Text Available 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.

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

    Science.gov (United States)

    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.

  17. Influenza A facilitates sensitization to house dust mite in infant mice leading to an asthma phenotype in adulthood

    KAUST Repository

    Al-Garawi, A

    2011-08-31

    The origins of allergic asthma, particularly in infancy, remain obscure. Respiratory viral infections and allergen sensitization in early life have been associated with asthma in young children. However, a causal link has not been established. We investigated whether an influenza A infection in early life alters immune responses to house dust mite (HDM) and promotes an asthmatic phenotype later in life. Neonatal (8-day-old) mice were infected with influenza virus and 7 days later, exposed to HDM for 3 weeks. Unlike adults, neonatal mice exposed to HDM exhibited negligible immune responsiveness to HDM, but not to influenza A. HDM responsiveness in adults was associated with distinct Ly6c + CD11b + inflammatory dendritic cell and CD8α + plasmacytoid (pDC) populations that were absent in HDM-exposed infant mice, suggesting an important role in HDM-mediated inflammation. Remarkably, HDM hyporesponsiveness was overcome when exposure occurred concurrently with an acute influenza infection; young mice now displayed robust allergen-specific immunity, allergic inflammation, and lung remodeling. Remodeling persisted into early adulthood, even after prolonged discontinuation of allergen exposure and was associated with marked impairment of lung function. Our data demonstrate that allergen exposure coincident with acute viral infection in early life subverts constitutive allergen hyporesponsiveness and imprints an asthmatic phenotype in adulthood.

  18. Bee Venom Phospholipase A2 Ameliorates House Dust Mite Extract Induced Atopic Dermatitis Like Skin Lesions in Mice

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    Kyung-Hwa Jung

    2017-02-01

    Full Text Available Atopic dermatitis (AD is a biphasic inflammatory skin disease that is provoked by epidermal barrier defects, immune dysregulation, and increased skin infections. Previously, we have demonstrated that bvPLA2 evoked immune tolerance by inducing regulatory T cells (Treg, and thus alleviated Th2 dominant allergic asthma in mice. Here, we would like to determine whether treatment with bvPLA2 exacerbates the AD-like allergic inflammations induced by house dust mite extract (DFE in a murine model. Epidermal thickness, immune cell infiltration, serum immunoglobulin, and cytokines were measured. Ear swelling, skin lesions, and the levels of total serum IgE and Th1/Th2 cytokines were elevated in DFE/DNCB-induced AD mice. Topical application of bvPLA2 elicited significant suppression of the increased AD symptoms, including ear thickness, serum IgE concentration, inflammatory cytokines, and histological changes. Furthermore, bvPLA2 treatment inhibited mast cell infiltration into the ear. On the other hand, Treg cell depletion abolished the anti-atopic effects of bvPLA2, suggesting that the effects of bvPLA2 depend on the existence of Tregs. Taken together, the results revealed that topical exposure to bvPLA2 aggravated atopic skin inflammation, suggesting that bvPLA2 might be a candidate for the treatment of AD.

  19. A GM-CSF/IL-33 pathway facilitates allergic airway responses to sub-threshold house dust mite exposure.

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    Alba Llop-Guevara

    Full Text Available Allergic asthma is a chronic immune-inflammatory disease of the airways. Despite aeroallergen exposure being universal, allergic asthma affects only a fraction of individuals. This is likely related, at least in part, to the extent of allergen exposure. Regarding house dust mite (HDM, we previously identified the threshold required to elicit allergic responses in BALB/c mice. Here, we investigated the impact of an initial immune perturbation on the response to sub-threshold HDM exposure. We show that transient GM-CSF expression in the lung facilitated robust eosinophilic inflammation, long-lasting antigen-specific Th2 responses, mucus production and airway hyperresponsiveness. This was associated with increased IL-33 levels and activated CD11b(+ DCs expressing OX40L. GM-CSF-driven allergic responses were significantly blunted in IL-33-deficient mice. IL-33 was localized on alveolar type II cells and in vitro stimulation of human epithelial cells with GM-CSF enhanced intracellular IL-33 independently of IL-1α. Likewise, GM-CSF administration in vivo resulted in increased levels of IL-33 but not IL-1α. These findings suggest that exposures to environmental agents associated with GM-CSF production, including airway infections and pollutants, may decrease the threshold of allergen responsiveness and, hence, increase the susceptibility to develop allergic asthma through a GM-CSF/IL-33/OX40L pathway.

  20. Proteolytic Activity Present in House-Dust-Mite Extracts Degrades ENA-78/CXCL5 and Reduces Neutrophil Migration.

    Science.gov (United States)

    Keglowich, Laura; Tamm, Michael; Zhong, Jun; Miglino, Nicola; Borger, Pieter

    2014-01-01

    Background. Bronchial smooth muscle cells (BSMC) are a major source of proinflammatory and proangiogenic cytokines and chemokines, including VEGF and CXC-chemokines. CXC-chemokines act primarily on neutrophils, mediating their recruitment to and activation at the site of inflammation. In humans, house-dust mite (HDM) allergens can cause asthmatic exacerbations and trigger an inflammatory response through protease-dependent mechanisms. Objective. We investigated the effect HDM extract on the release of pro-angiogenic and proinflammatory cytokines from BSMC. Methods. Human primary BSMC were stimulated with HDM extract in the absence or presence of fetal calf serum (FCS). Twenty angiogenic cytokines were detected by a specific antibody array and modified protein levels were confirmed by ELISA. Neutrophil migration was measured using a 96-well Boyden chamber. Results. ENA-78/CXCL5 protein levels in conditioned medium of BSMC stimulated with HDM extract were significantly reduced (n = 10, P ENA-78/CXCL5 mRNA levels. Recombinant ENA-78/CXCL5 was degraded after incubation with HDM extracts (n = 7, P ENA-78/CXCL5 was also reduced in the presence of HDM extract. Conclusion. HDM proteases degrade ENA-78/CXCL5. Thus exposure to HDM allergens may alter ENA-78/CXCL5 levels in the lungs and may affect angiogenesis and the inflammatory response in the airways of asthma patients.

  1. High-level expression and purification of the major house dust mite allergen Der p 2 in Escherichia coli.

    Science.gov (United States)

    Cao, Tuo; Zhang, Zhang; Liu, Zhi-Gao; Dou, Xia; Zhang, Jie; Zhang, Wei; Wu, Bo; Yu, Zhen-Dong; Wei, Zhun; Yu, Bo

    2016-05-01

    Der p 2, a major allergen derived from the house dust mite Dermatophagoides pteronyssinus, is one of the most clinically relevant allergens worldwide. Recombinant Der p 2 (rDer p 2) is useful in clinical diagnosis and disease-specific immunotherapy. However, previous studies showed that Der p 2 can only be expressed in Escherichia coli (E. coli) cells as inclusion bodies, thus protein refolding is required to obtain functional products. Here we report a new method to produce biologically active Der p 2 protein in E. coli. N-terminal hexahistidine- and trigger factor (TF)-tagged Der p 2 was expressed in soluble form in E. coli and purified using a combination of chromatography processes. This procedure produced milligram-level high purity Der p 2 per liter of bacterial culture. Moreover, far-UV region circular dichroism (CD) analysis and serum specific IgE reactivity test demonstrated that the secondary structure and IgE reactivity properties of rDer p 2 produced in our study were almost identical to those of natural Der p 2 (nDer p 2). In conclusion, the method developed in this work provides a useful tool for the production of immunologically active recombinant Der p 2 for clinical applications.

  2. A CCL24-dependent pathway augments eosinophilic airway inflammation in house dust mite-challenged Cd163(-/-) mice.

    Science.gov (United States)

    Dai, C; Yao, X; Gordon, E M; Barochia, A; Cuento, R A; Kaler, M; Meyer, K S; Keeran, K J; Nugent, G Z; Jeffries, K R; Qu, X; Yu, Z-X; Aponte, A; Gucek, M; Dagur, P K; McCoy, J P; Levine, S J

    2016-05-01

    CD163 is a macrophage scavenger receptor with anti-inflammatory and pro-inflammatory functions. Here, we report that alveolar macrophages (AMΦs) from asthmatic subjects had reduced cell-surface expression of CD163, which suggested that CD163 might modulate the pathogenesis of asthma. Consistent with this, house dust mite (HDM)-challenged Cd163(-/-) mice displayed increases in airway eosinophils and mucous cell metaplasia (MCM). The increased airway eosinophils and MCM in HDM-challenged Cd163(-/-) mice were mediated by augmented CCL24 production and could be reversed by administration of a neutralizing anti-CCL24 antibody. A proteomic analysis identified the calcium-dependent binding of CD163 to Dermatophagoides pteronyssinus peptidase 1 (Der p1). Der p1-challenged Cd163(-/-) mice had the same phenotype as HDM-challenged Cd163(-/-) mice with increases in airway eosinophils, MCM and CCL24 production, while Der p1 induced CCL24 secretion by bone marrow-derived macrophages (BMMΦs) from Cd163(-/-) mice, but not BMMΦs from wild-type (WT) mice. Finally, airway eosinophils and bronchoalveolar lavage fluid CCL24 levels were increased in Der p1-challenged WT mice that received adoptively transferred AMΦ's from Cd163(-/-) mice. Thus, we have identified CD163 as a macrophage receptor that binds Der p1. Furthermore, we have shown that HDM-challenged Cd163(-/-) mice have increased eosinophilic airway inflammation and MCM that are mediated by a CCL24-dependent mechanism.

  3. A review on emerging frontiers of house dust mite and cockroach allergy research.

    Science.gov (United States)

    Patel, S; Meher, B R

    Currently, mankind is afflicted with diversified health issues, allergies being a common, yet little understood malady. Allergies, the outcome of a baffled immune system encompasses myriad allergens and causes an array of health consequences, ranging from transient to recurrent and mild to fatal. Indoor allergy is a serious hypersensitivity in genetically-predisposed people, triggered by ingestion, inhalation or mere contact of allergens, of which mite and cockroaches are one of the most-represented constituents. Arduous to eliminate, these aeroallergens pose constant health challenges, mostly manifested as respiratory and dermatological inflammations, leading to further aggravations if unrestrained. Recent times have seen an unprecedented endeavour to understand the conformation of these allergens, their immune manipulative ploys and other underlying causes of pathogenesis, most importantly therapies. Yet a large section of vulnerable people is ignorant of these innocuous-looking immune irritants, prevailing around them, and continues to suffer. This review aims to expedite this field by a concise, informative account of seminal findings in the past few years, with particular emphasis on leading frontiers like genome-wide association studies (GWAS), epitope mapping, metabolomics etc. Drawbacks linked to current approaches and solutions to overcome them have been proposed. Copyright © 2016 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

  4. An evaluation of three predatory mite species for the control of greenhouse whitefly (Trialeurodes vaporariorum).

    Science.gov (United States)

    Medd, Nathan C; GreatRex, Richard M

    2014-10-01

    Within integrated pest control programmes, the use of high mite inoculations to control hot spots of whitefly is desirable for many growers. In this experiment, two species of predatory mites established as commercial biological control agents, Typhlodromips montdorensis and Amblyseius swirskii (Acari: Phytoseiidae), were compared with another, more recently introduced species, Amblydromalus limonicus, for their ability to control dense populations of greenhouse whitefly (Trialeurodes vaporariorum) on cucumber plants (Cucumis sativus). Mite formulation type had a significant effect on the number of mites found on plants, but this did not correspond to increased whitefly control. Plots treated with A. limonicus or T. montdorensis, applied as loose product, had significantly reduced whitefly populations throughout the trial. Analysis showed that no species was observed more often on leaves with higher whitefly densities than on those with lower densities. No species was clearly identified as a suitable candidate for treatment of high-density whitefly colonies, but results suggest the highest level of predation in A. limonicus. Strategies for the effective use of these predatory mite species in control programmes are discussed. © 2014 Society of Chemical Industry.

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

    Science.gov (United States)

    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 30 years old (p 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.

  6. Indoor viable dust-bound microfungi in relation to residential characteristics, living habits, and symptoms in atopic and control children.

    Science.gov (United States)

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

    1992-03-01

    Floor dust was collected in the wintertime from the homes of 61 children sensitized to house dust mites, 57 children with sensitization to other aeroallergens, and 57 nonatopic control children. The dust was cultivated and microfungal growth was identified microscopically. Indoor humidity was measured, and condensation on windowpanes was registered during 1 winter week. Housing and sociodemographic and symptom data were obtained by a questionnaire. Penicillium, Alternaria, and Cladosporium were the three most common microfungi. The mean total number of colony-forming units per 30 mg of dust was significantly lower in the homes of the two atopic groups than in homes of the control group, which may be a result of allergen-sanitation measures. High colony-forming unit counts appeared to be related to damp housing. Weak associations were found between the occurrence of viable fungi in dust and allergic symptoms among the house dust mite-sensitized children. However, no consistent association between viable mold growth and sensitization to molds was observed. The health implications of indoor fungal exposure still remain unclear.

  7. Detection of a novel 20 kDa shrimp allergen showing cross-reactivity to house dust mites.

    Science.gov (United States)

    Villalta, D; Tonutti, E; Visentini, D; Bizzaro, N; Roncarolo, D; Amato, S; Mistrello, G

    2010-02-01

    Allergy to crustacean shellfish is one of the most common IgE-mediated food allergies, and tropomyosin has been identified as the major allergen. However, not all subjects affected by this allergy are IgE-positive to tropomyosin. To evaluate whether sera of patients with shrimp allergy but negative for tropomyosin react to other allergen(s); and to evaluate the role such allergen(s) may play in cross-reactivity between crustaceans and house dust mites (HDMs). Three different pools of sera-one from subjects with shellfish allergy and HDMs positivity, but negative for recombinant and native tropomyosin (rPen a 1 and nPen m 1) (Pool 2); a second from subjects with tropomyosin and HDMs positivity (Pool 1); and the last from subjects allergic only to HDMs (Pool 3) were submitted to immunoblotting. Subsequently, a 20 kDa protein- enriched fraction of shrimp extract was used at two different concentrations (10 and 100 microg/mL) to pre-absorb the Pool 2 serum and to evaluate, by ELISA assay, the level of inhibition on shrimp and HDMs-coated wells, respectively. The Pool 2 serum showed IgE reactivity against a 20 kDa component. Its pre-absorption with an enriched fraction of 20 kDa protein caused an inhibition of 56% in IgE binding to shrimp extract at a concentration of 100 microg/mL, and of 14% and 35% to HDMs extract at concentrations of 10 and 100 microg/mL, respectively, as measured by ELISA assay. The 20 kDa component seems to be a new crustacean allergen and it could play a role in cross-reactivity with HDMs.

  8. Dermatophagoides farinae house dust mite allergen challenges reduce stratum corneum ceramides in an experimental dog model of acute atopic dermatitis.

    Science.gov (United States)

    Stahl, Jessica; Paps, Judy; Bäumer, Wolfgang; Olivry, Thierry

    2012-12-01

    Ceramides are essential stratum corneum (SC) lipids and they play a pivotal role in maintaining effective cutaneous barrier function. The present study aimed at determining the effect of a Dermatophagoides farinae house dust mite (Df-HDM) allergen challenge on SC ceramides of atopic dogs experimentally sensitized to these allergens. Six Df-HDM-sensitized atopic Maltese-beagle dogs were used. Prechallenge SC was obtained by cyanoacrylate stripping. One week later, the dogs were challenged topically with Df-HDM allergens, which resulted in mild to moderate inflammation 24 h later. Two weeks after challenge, SC of lesional and nonlesional skin was obtained. Finally, SC was collected from challenge sites 2 months after lesion resolution. The different SC lipids were quantified blindly by thin-layer chromatography. Significantly lower amounts of ceramides [AH], [AP], [AS], [NP], [EOP], [NS] and [EOS] were observed in lesional SC compared with prechallenge samples, while no significant effect was found on the amount of other lipids, including cholesterol and free fatty acids. The ceramide profile of nonlesional skin generally showed the same postchallenge reduction pattern. Ceramide amounts returned to normal within 2 months after lesion remission. These findings suggest that the allergic reactions caused by Df-HDM allergens lead to a selective reduction of SC ceramides, not only at sites of inflammation but also at sites away from those of allergen application. There is normalization of ceramide amounts after inflammation subsides. These observations suggest that the deficiency of ceramides observed in canine atopic skin occurs, at least in part, secondary to inflammation. © 2012 The Authors. Veterinary Dermatology © 2012 ESVD and ACVD.

  9. Neutralisation of interleukin-13 in mice prevents airway pathology caused by chronic exposure to house dust mite.

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    Kate L Tomlinson

    Full Text Available BACKGROUND: Repeated exposure to inhaled allergen can cause airway inflammation, remodeling and dysfunction that manifests as the symptoms of allergic asthma. We have investigated the role of the cytokine interleukin-13 (IL-13 in the generation and persistence of airway cellular inflammation, bronchial remodeling and deterioration in airway function in a model of allergic asthma caused by chronic exposure to the aeroallergen House Dust Mite (HDM. METHODOLOGY/PRINCIPAL FINDINGS: Mice were exposed to HDM via the intranasal route for 4 consecutive days per week for up to 8 consecutive weeks. Mice were treated either prophylactically or therapeutically with a potent neutralising anti-IL-13 monoclonal antibody (mAb administered subcutaneously (s.c.. Airway cellular inflammation was assessed by flow cytometry, peribronchial collagen deposition by histocytochemistry and airway hyperreactivity (AHR by invasive measurement of lung resistance (R(L and dynamic compliance (C(dyn. Both prophylactic and therapeutic treatment with an anti-IL-13 mAb significantly inhibited (P<0.05 the generation and maintenance of chronic HDM-induced airway cellular inflammation, peribronchial collagen deposition, epithelial goblet cell upregulation. AHR to inhaled methacholine was reversed by prophylactic but not therapeutic treatment with anti-IL-13 mAb. Both prophylactic and therapeutic treatment with anti-IL-13 mAb significantly reversed (P<0.05 the increase in baseline R(L and the decrease in baseline C(dyn caused by chronic exposure to inhaled HDM. CONCLUSIONS/SIGNIFICANCE: These data demonstrate that in a model of allergic lung disease driven by chronic exposure to a clinically relevant aeroallergen, IL-13 plays a significant role in the generation and persistence of airway inflammation, remodeling and dysfunction.

  10. The Roles of Malassezia Yeast and House Dust Mites in Atopic Dermatitis with Head and Neck Involvement

    Directory of Open Access Journals (Sweden)

    Gökhan Okan

    2013-03-01

    Full Text Available Objective: The aim of the present study was to evaluate to the effects of Dermatophagoides pteronyssinus, Dermatophagoides farinea and Pityrosporum ovale allergens on atopic dermatitis and to compare the patients with and without head and neck involvement. Moreover, the effect of P. ovale on atopic dermatitis according to different geographic conditions was also determined. Methods: Thirty-one patients with atopic dermatitis, who were admitted to İstanbul Medical Faculty Dermatology Clinic, were enrolled. Skin prick tests were performed for P. ovale and house dust mites (D. pteronyssinus ve D. farinea Results: Ten patients (32.3% showed positive reaction to D. pteronyssinus, nine patients (29% to D. farinea, and nine patients (29% to P. ovale. Head and neck involvement was observed in 22 patients. Head and neck involvement was mostly seen in the patients in the first two decades of life (48%. Eczema was significantly more severe in the patients with head and neck involvement compared to that in those without (p500 IU/mL were significantly higher in the head and neck involvement group (p<0.05. Conclusion: Although the effect of P. ovale on atopic dermatitis in head and neck involvement could not be demonstrated in the present study, it should not be ignored. The results of skin prick test for P. ovale might change according to age and disease severity. Geographical variations of Malassezia species distribution should be kept in mind while evaluating test results. Moreover, it should be remembered that inhalan allergens are also triggering factor in some patients with atopic dermatitis with head and neck involvement.

  11. Proteolytic Activity Present in House-Dust-Mite Extracts Degrades ENA-78/CXCL5 and Reduces Neutrophil Migration

    Directory of Open Access Journals (Sweden)

    Laura Keglowich

    2014-01-01

    Full Text Available Background. Bronchial smooth muscle cells (BSMC are a major source of proinflammatory and proangiogenic cytokines and chemokines, including VEGF and CXC-chemokines. CXC-chemokines act primarily on neutrophils, mediating their recruitment to and activation at the site of inflammation. In humans, house-dust mite (HDM allergens can cause asthmatic exacerbations and trigger an inflammatory response through protease-dependent mechanisms. Objective. We investigated the effect HDM extract on the release of pro-angiogenic and proinflammatory cytokines from BSMC. Methods. Human primary BSMC were stimulated with HDM extract in the absence or presence of fetal calf serum (FCS. Twenty angiogenic cytokines were detected by a specific antibody array and modified protein levels were confirmed by ELISA. Neutrophil migration was measured using a 96-well Boyden chamber. Results. ENA-78/CXCL5 protein levels in conditioned medium of BSMC stimulated with HDM extract were significantly reduced (n=10, P<0.05 but restored in the presence of 5% FCS. HDM extracts did not affect ENA-78/CXCL5 mRNA levels. Recombinant ENA-78/CXCL5 was degraded after incubation with HDM extracts (n=7, P<0.05 but restored after the addition of the serine protease AEBSF. Neutrophil migration towards recombinant ENA-78/CXCL5 was also reduced in the presence of HDM extract. Conclusion. HDM proteases degrade ENA-78/CXCL5. Thus exposure to HDM allergens may alter ENA-78/CXCL5 levels in the lungs and may affect angiogenesis and the inflammatory response in the airways of asthma patients.

  12. Protective Roles for RGS2 in a Mouse Model of House Dust Mite-Induced Airway Inflammation

    Science.gov (United States)

    George, Tresa; Bell, Matthew; Chakraborty, Mainak; Siderovski, David P.; Giembycz, Mark A.

    2017-01-01

    The GTPase-accelerating protein, regulator of G-protein signalling 2 (RGS2) reduces signalling from G-protein-coupled receptors (GPCRs) that signal via Gαq. In humans, RGS2 expression is up-regulated by inhaled corticosteroids (ICSs) and long-acting β2-adrenoceptor agonists (LABAs) such that synergy is produced in combination. This may contribute to the superior clinical efficacy of ICS/LABA therapy in asthma relative to ICS alone. In a murine model of house dust mite (HDM)-induced airways inflammation, three weeks of intranasal HDM (25 μg, 3×/week) reduced lung function and induced granulocytic airways inflammation. Compared to wild type animals, Rgs2-/- mice showed airways hyperresponsiveness (increased airways resistance and reduced compliance). While HDM increased pulmonary inflammation observed on hematoxylin and eosin-stained sections, there was no difference between wild type and Rgs2-/- animals. HDM-induced mucus hypersecretion was also unaffected by RGS2 deficiency. However, inflammatory cell counts in the bronchoalveolar lavage fluid of Rgs2-/- animals were significantly increased (57%) compared to wild type animals and this correlated with increased granulocyte (neutrophil and eosinophil) numbers. Likewise, cytokine and chemokine (IL4, IL17, IL5, LIF, IL6, CSF3, CXCLl, CXCL10 and CXCL11) release was increased by HDM exposure. Compared to wild type, Rgs2-/- animals showed a trend towards increased expression for many cytokines/chemokines, with CCL3, CCL11, CXCL9 and CXCL10 being significantly enhanced. As RGS2 expression was unaffected by HDM exposure, these data indicate that RGS2 exerts tonic bronchoprotection in HDM-induced airways inflammation. Modest anti-inflammatory and anti-remodelling roles for RGS2 are also suggested. If translatable to humans, therapies that maximize RGS2 expression may prove advantageous. PMID:28107494

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

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    Korneliusz Golebski

    Full Text Available 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.

  14. Understanding the biology and control of the poultry red mite Dermanyssus gallinae: a review.

    Science.gov (United States)

    Pritchard, James; Kuster, Tatiana; Sparagano, Olivier; Tomley, Fiona

    2015-01-01

    Dermanyssus gallinae, the poultry red mite (PRM), is a blood-feeding ectoparasite capable of causing pathology in birds, amongst other animals. It is an increasingly important pathogen in egg layers and is responsible for substantial economic losses to the poultry industry worldwide. Even though PRM poses a serious problem, very little is known about the basic biology of the mite. Here we review the current body of literature describing red mite biology and discuss how this has been, or could be, used to develop methods to control PRM infestations. We focus primarily on the PRM digestive system, salivary glands, nervous system and exoskeleton and also explore areas of PRM biology which have to date received little or no study but have the potential to offer new control targets.

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

    Directory of Open Access Journals (Sweden)

    James D Johnston

    Full Text Available 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.

  16. In vivo and in vitro studies of Th17 response to specific immunotherapy in house dust mite-induced allergic rhinitis patients.

    Directory of Open Access Journals (Sweden)

    Chun Wei Li

    Full Text Available T helper (Th17 cells have been implicated in the development of allergic rhinitis (AR, but their response to specific immunotherapy (SIT remains unclear. We investigated the impact of SIT on Th17 response and Th1/Th2 changes in AR patients. Blood samples from AR patients (n = 20 who were monosensitized to house dust mite (HDM were collected before the initiation of SIT (SIT-untreated and after the end of 2-year SIT (SIT-treated treatment. Twenty healthy volunteers were recruited as controls. In vitro HDM stimulation in peripheral blood mononuclear cells (PBMCs was also performed. Expression levels of Th17 associated genes were determined in both PBMCs and plasma by PCR and ELISA, while Th17/Th1/Th2/IL10 producing cell proportions were evaluated in PBMCs by flow cytometry. The SIT effect was evaluated by assessing clinical symptoms. mRNA levels of Th17 specific genes (IL17 and RORC were increased in SIT-untreated AR versus controls, and decreased following SIT treatment. SIT can change the production of Th17 associated genes (reduction of IL17, IL6, and IL23, but increase of IL27 in plasma from AR patients. Th2/Th1 ratio and proportions of Th17 cells were suppressed while IL10 producing CD4+ T cells were elevated after SIT. In vitro HDM challenge presents concordant patterns with in vivo findings: 1 increase of Th2 and Th17 response in AR patients; 2 suppression of IL10 producing CD4+ T cells in SIT-untreated AR but elevation in SIT-treated AR patients. Most importantly, a positive correlation between IL17 mRNA/protein levels and clinical symptom scores was observed. SIT significantly inhibits Th17 mediated inflammation in AR and IL17 may be a useful biomarker for both AR severity and SIT therapeutic effect.Australian New Zealand Clinical Trials Registry (ANZCTR ACTRN12613000445774.

  17. Single versus multiple enemies and the impact on biological control of spider mites in cassava fields in West-Africa

    NARCIS (Netherlands)

    Onzo, A.; Sabelis, M.W.; Hanna, R.

    2014-01-01

    To determine whether to use single or multiple predator species for biological pest control requires manipulative field experiments. We performed such tests in Benin (West Africa) in cassava fields infested by the cassava green mite Mononychellus tanajoa, and the cotton red mite Oligonychus

  18. Mite Pests in Plant Crops – Current Issues, Inovative Approaches and Possibilities for Controlling Them (2

    Directory of Open Access Journals (Sweden)

    Radmila Petanović

    2010-01-01

    Full Text Available Part one discusses some principal mite pests in agroecosystems and urban horticulturein European countries, Serbia and its neighbouring countries focusing primarily on issueswith regard to plant production, novel methods and approaches in applied acaralogy. Parttwo displays some major properties of acaricides inhibiting respiration, growth and developmentand other synthetic substances with acaricide action on the market in the last decadeof the 20th century and the first decade of the 21st century. Also some products of naturalorigin (azadirachtin, oils, micoacaricides are said to be gaining in importance. Issues withregard to the fact that mites can readily develop resistance to acardicides are discussed anda survey on the results of biochemical, physiological and genetical causes of resistance areanalyzed. Some basic principles of biological control of phytophagous mites and modernadvances and approaches are discussed as well as current knowledge on host plant resistanceto mites. Eventually, the possibility of using a combination of selective acaricides andbiological control agents is discussed but also the inclusion of other modes of control (agriculturalpractices and physical measures expected to contribute to an integrated managementof pest populations.

  19. [Analysis of adverse reactions induced by subcutaneous immunotherapy against dust mite allergy in 234 cases with allergic rhinitis and asthma].

    Science.gov (United States)

    Li, Meng-rong; Wang, Xiao-ning; Jiang, Han-dan; Wang, Qiong-yan; Li, Ying-chun; Lin, Jian; Jin, Ke; Zhang, Hai-lin; Li, Chang-chong

    2012-10-01

    To investigate the incidence of local reactions (LRs) and systemic reactions (SRs) of subcutaneous immunotherapy (SCIT) and to analyze the potential risk factors of such reactions in Chinese population. This is a retrospective study on 234 dust mite sensitized patients with allergic rhinitis and asthma who received allergen immunotherapy in our hospital from 2003 to 2010. Chart review was conducted to capture clinical data of reactions to immunotherapy. Parameters included signs and symptoms, the onset of reaction, and interventions in treating such reactions, particularly, the administration of epinephrine (EPI) and adjustment of vaccine dosage due to LRs and SRs. The 234 patients received a total of 7679 injections. Among them, 4973 LRs (64.8%) and 235 SRs (3.1%) were observed in 67 patients (28.6% of all patients). SRs included respiratory symptoms (205 events, 88.4%) and cutaneous symptoms (31.5%). Of the total of 235 SR events, 212 (90.2%) were presented as mild SRs and 23 (9.8%) were in severe SR category (grade III and grade IV, EAACI grading system). Overall, severe SRs accounted for 0.3% of total injections. Seventeen of the 23 SR events required epinephrine treatment (0.2% of total injections). Of the 67 patients, 61 completed the course of treatment after dose adjustment; 36 patients had their doses decreased prior to further advancing to target dose. Nineteen subjects tolerated splitting two injections at 30 minutes interval. Six patients advanced the dose based on protocol and another 6 had to stop immunotherapy. Most of the SRs (77.4%) occurred during the maintenance phase of immunotherapy. The levels of TIgE, SIgE D1 and SIgE D2 were found to be significantly higher in patients with SRs comparing to patients without SRs (P < 0.05). SRs more commonly occurred in patients with age less than 14 years than their older counterparts (95.5% vs. 85.6%, OR = 3.58, 95%CI = 1.040 - 12.322, P < 0.01). The incidence of SRs were significantly higher in asthma

  20. Der f 35: An MD-2-like house dust mite allergen that cross-reacts with Der f 2 and Pso o 2.

    Science.gov (United States)

    Fujimura, T; Aki, T; Isobe, T; Matsuoka, A; Hayashi, T; Ono, K; Kawamoto, S

    2017-04-25

    Dermatophagoides farinae is a source of airborne house dust mite (HDM) allergens. We elucidated IgE-reactive allergens from D. farinae by two-dimensional immunoblotting-based allergenome analysis, and identified one new allergen, named Der f 35, that possesses IgE-binding capacity comparable to that of Der f 2. The aim of this study was to clarify the allergenic capacity of new HDM allergen Der f 35. We cloned der f 35 from D. farinae mRNA and produced recombinant Der f 35 in Escherichia coli. The IgE-binding capacity of Der f 35 and its cross-reactivity with group 2 allergens from D. farinae and Psoroptes ovis were determined by enzyme-linked immunosorbent assay (ELISA) and ELISA inhibition assays, respectively. The deduced amino acid sequence for der f 35, which possesses the MD-2-related lipid-recognition domain, showed higher identity with group 2 allergens from P. ovis (61.5%) and Blomia tropicalis (50.7%) than with Der f 2 (40.8%). Der f 35 showed IgE-binding frequencies of 77.5% (31/40) for the native form upon allergenome analysis and 51.4% (18/35) for recombinant structure by ELISA. Der f 35 showed cross-reactivity with Der f 2 and Pso o 2 in reaction with HDM-allergic patients' IgE by ELISA inhibition assay. Der f 35 is a candidate major allergen from D. farinae, which is more similar to group 2 allergens from sheep scab mite and storage mites. Der f 35 could be responsible for the cross-reactivity among group 2 mite allergens. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  1. Acaricide treatment affects viral dynamics in Varroa destructor-infested honey bee colonies via both host physiology and mite control.

    Science.gov (United States)

    Locke, Barbara; Forsgren, Eva; Fries, Ingemar; de Miranda, Joachim R

    2012-01-01

    Honey bee (Apis mellifera) colonies are declining, and a number of stressors have been identified that affect, alone or in combination, the health of honey bees. The ectoparasitic mite Varroa destructor, honey bee viruses that are often closely associated with the mite, and pesticides used to control the mite population form a complex system of stressors that may affect honey bee health in different ways. During an acaricide treatment using Apistan (plastic strips coated with tau-fluvalinate), we analyzed the infection dynamics of deformed wing virus (DWV), sacbrood virus (SBV), and black queen cell virus (BQCV) in adult bees, mite-infested pupae, their associated Varroa mites, and uninfested pupae, comparing these to similar samples from untreated control colonies. Titers of DWV increased initially with the onset of the acaricide application and then slightly decreased progressively coinciding with the removal of the Varroa mite infestation. This initial increase in DWV titers suggests a physiological effect of tau-fluvalinate on the host's susceptibility to viral infection. DWV titers in adult bees and uninfested pupae remained higher in treated colonies than in untreated colonies. The titers of SBV and BQCV did not show any direct relationship with mite infestation and showed a variety of possible effects of the acaricide treatment. The results indicate that other factors besides Varroa mite infestation may be important to the development and maintenance of damaging DWV titers in colonies. Possible biochemical explanations for the observed synergistic effects between tau-fluvalinate and virus infections are discussed.

  2. Neoseiulus paspalivorus, a predator from coconut, as a candidate for controlling dry bulb mites infesting stored tulip bulbs.

    Science.gov (United States)

    Lesna, Izabela; da Silva, Fernando R; Sato, Yukie; Sabelis, Maurice W; Lommen, Suzanne T E

    2014-06-01

    The dry bulb mite, Aceria tulipae, is the most important pest of stored tulip bulbs in The Netherlands. This tiny, eriophyoid mite hides in the narrow space between scales in the interior of the bulb. To achieve biological control of this hidden pest, candidate predators small enough to move in between the bulb scales are required. Earlier experiments have shown this potential for the phytoseiid mite, Neoseiulus cucumeris, but only after the bulbs were exposed to ethylene, a plant hormone that causes a slight increase in the distance between tulip bulb scales, just sufficient to allow this predator to reach the interior part of the bulb. Applying ethylene, however, is not an option in practice because it causes malformation of tulip flowers. In fact, to prevent this cosmetic damage, bulb growers ventilate rooms where tulip bulbs are stored, thereby removing ethylene produced by the bulbs (e.g. in response to mite or fungus infestation). Recently, studies on the role of predatory mites in controlling another eriophyoid mite on coconuts led to the discovery of an exceptionally small phytoseiid mite, Neoseiulus paspalivorus. This predator is able to move under the perianth of coconuts where coconut mites feed on meristematic tissue of the fruit. This discovery prompted us to test N. paspalivorus for its ability to control A. tulipae on tulip bulbs under storage conditions (ventilated rooms with bulbs in open boxes; 23 °C; storage period June-October). Using destructive sampling we monitored predator and prey populations in two series of replicated experiments, one at a high initial level of dry bulb mite infestation, late in the storage period, and another at a low initial dry bulb mite infestation, halfway the storage period. The first and the second series involved treatment with N. paspalivorus and a control experiment, but the second series had an additional treatment in which the predator N. cucumeris was released. Taking the two series of experiments together

  3. Chemical control of the red palm mite, Raoiella indica (Acari: Tenuipalpidae) in banana and coconut.

    Science.gov (United States)

    Rodrigues, Jose Carlos Verle; Peña, J E

    2012-08-01

    The red palm mite (RPM), Raoiella indica Hirst, is a predominant pest of coconuts, date palms and other palm species, as well as a major pest of bananas (Musa spp.) in different parts of the world. Recently, RPM dispersed throughout the Caribbean islands and has reached both the North and South American continents. The RPM introductions have caused severe damage to palm species, and bananas and plantains in the Caribbean region. The work presented herein is the result of several acaricide trials conducted in Puerto Rico and Florida on palms and bananas in order to provide chemical control alternatives to minimize the impact of this pest. Spiromesifen, dicofol and acequinocyl were effective in reducing the population of R. indica in coconut in Puerto Rico. Spray treatments with etoxanole, abamectin, pyridaben, milbemectin and sulfur showed mite control in Florida. In addition, the acaricides acequinocyl and spiromesifen were able to reduce the population of R. indica in banana trials.

  4. The prevalence of indoor allergens in the Baltimore area: house dust-mite and animal-dander antigens measured by immunochemical techniques.

    Science.gov (United States)

    Lind, P; Norman, P S; Newton, M; Løwenstein, H; Schwartz, B

    1987-10-01

    Mattress dust samples from 42 homes in Baltimore, Md., were analyzed by ELISA and rocket immunoelectrophoresis (RIE) for major excrement allergens (P1 [equal to Dp 42], Df 6, and Dm 6) of house dust mites, Dermatophagoides pteronyssinus, D. farinae, and D. microceras, by RIE for cat major epithelial allergen (cat Ag 1) and horse major epithelial antigen (horse Ag 11), and by counter-current immunoelectrophoresis (CCIE) for cat and dog antigens. Dp 42 was detected by ELISA in 24 samples (57%) and Df 6 in 39 samples (92%). All samples were negative to Dm 6. Recorded levels varied from 50 ng of allergen per gram of dust (detection limit) to 15,000 ng/gm. A combined content of Dp 42 and Df 6 greater than 700 ng/gm was associated with a positive reaction in RIE. Concentrations of Dp 42 and Df 6 did not correlate (rS = 0.21; p greater than 0.05). Cat and dog antigens were frequently detected by CCIE (77% and 63%, respectively). CCIE titer to cat correlated well with quantitation of cat Ag 1 by RIE (p less than 0.01). Horse antigen was detected in few homes (5%). None of the specific allergen determinations correlated with levels of human serum albumin determined by RIE.

  5. Anti-angiogenic Nanotherapy Inhibits Airway Remodeling and Hyper-responsiveness of Dust Mite Triggered Asthma in the Brown Norway Rat

    Science.gov (United States)

    Lanza, Gregory M.; Jenkins, John; Schmieder, Anne H.; Moldobaeva, Aigul; Cui, Grace; Zhang, Huiying; Yang, Xiaoxia; Zhong, Qiong; Keupp, Jochen; Sergin, Ismail; Paranandi, Krishna S.; Eldridge, Lindsey; Allen, John S.; Williams, Todd; Scott, Michael J.; Razani, Babak; Wagner, Elizabeth M.

    2017-01-01

    Although angiogenesis is a hallmark feature of asthmatic inflammatory responses, therapeutic anti-angiogenesis interventions have received little attention. Objective: Assess the effectiveness of anti-angiogenic Sn2 lipase-labile prodrugs delivered via αvβ3-micellar nanotherapy to suppress microvascular expansion, bronchial remodeling, and airway hyper-responsiveness in Brown Norway rats exposed to serial house dust mite (HDM) inhalation challenges. Results: Anti-neovascular effectiveness of αvβ3-mixed micelles incorporating docetaxel-prodrug (Dxtl-PD) or fumagillin-prodrug (Fum-PD) were shown to robustly suppress neovascular expansion (p<0.01) in the upper airways/bronchi of HDM rats using simultaneous 19F/1H MR neovascular imaging, which was corroborated by adjunctive fluorescent microscopy. Micelles without a drug payload (αvβ3-No-Drug) served as a carrier-only control. Morphometric measurements of HDM rat airway size (perimeter) and vessel number at 21d revealed classic vascular expansion in control rats but less vascularity (p<0.001) after the anti-angiogenic nanotherapies. CD31 RNA expression independently corroborated the decrease in airway microvasculature. Methacholine (MCh) induced respiratory system resistance (Rrs) was high in the HDM rats receiving αvβ3-No-Drug micelles while αvβ3-Dxtl-PD or αvβ3-Fum-PD micelles markedly and equivalently attenuated airway hyper-responsiveness and improved airway compliance. Total inflammatory BAL cells among HDM challenged rats did not differ with treatment, but αvβ3+ macrophages/monocytes were significantly reduced by both nanotherapies (p<0.001), most notably by the αvβ3-Dxtl-PD micelles. Additionally, αvβ3-Dxtl-PD decreased BAL eosinophil and αvβ3+ CD45+ leukocytes relative to αvβ3-No-Drug micelles, whereas αvβ3-Fum-PD micelles did not. Conclusion: These results demonstrate the potential of targeted anti-angiogenesis nanotherapy to ameliorate the inflammatory hallmarks of asthma in a

  6. Field bioassay of Metarhizium anisopliae strains to control the poultry red mite Dermanyssus gallinae.

    Science.gov (United States)

    Tavassoli, M; Allymehr, M; Pourseyed, S H; Ownag, A; Bernousi, I; Mardani, K; Ghorbanzadegan, M; Shokrpoor, S

    2011-06-10

    The poultry red mite, Dermanyssus gallinae is one of the most economically deleterious ectoparasite of laying hens worldwide. To evaluate the efficacy of three strains (V245, 3247 and 715C) of entomopathogenic fungus Metarhizium anisopliae with potential as acaricides against D. gallinae, this investigation was carried out in a commercial caged laying poultry farm in Naghedeh, West Azarbaijan of Iran. The parasite infestation already existed in the farm. Sunflower oil suspension of all fungal strains, each in two concentrations (1×10(7) and 1×10(9) conidia/ml) were used separately as spray on hens and cages, and in the control group the cages were only sprayed with sunflower oil and sterile distilled water. For estimating the population rate of mites before and after treatment, special cardboard traps were fixed to cages during a 1-month period. The traps were placed on weeks -1, 0, 1, 2 and 3 and always removed after 1 w. The results showed that the population rates post fungal treatment with the lower concentration were not significantly different compared to the control group. However, the reduction in mite numbers induced by all three strains at the concentration of 1×10(9) conidia/ml was significantly higher than the control (Pgallinae.

  7. Control of insects and mites in grain using a high temperature/short time (HTST) technique.

    Science.gov (United States)

    Mourier; Poulsen

    2000-07-01

    Wheat infested with grain mites (Acari) and Sitophilus granarius, and maize infested with Prostephanus truncatus, were exposed to hot air in a CIMBRIA HTST Microline toaster((R)). Inlet temperatures of the hot air were in the range of 150-750 degrees C decreasing to outlet temperatures in the range of 100-300 degrees C during the exposure period. A rotating drum, connected to a natural-gas burner was fed with grain which was in constant movement along the drum and thereby mixed thoroughly during the process. The capacity of the toaster was 1000 kg per hour.Complete control of grain mites and adult S. granarius in wheat was obtained with an inlet temperature of 300-350 degrees C and an average residence time in the drum of 6 s. More than 99% mortality was obtained for all stages of S. granarius with an inlet temperature of 300-350 degrees C and an average exposure period of 40 s. For control of P. truncatus in maize, an inlet temperature of 700 degrees C resulted in a complete disinfestation when the exposure time was 19 s.The reduction in grain moisture content was 0.5-1% at treatments giving 100% control. Germination tests indicate that it is possible to choose a combination of inlet temperatures and exposure periods which effectively kills mites and insects in small grains, without harming the functional properties of the grain.Economy of the method was considered to be competitive with fumigation using phosphine.

  8. Increased ventilation rate as way to reduce the exposure to house dust mites and improve the health of asthmatic children - an intervention design

    DEFF Research Database (Denmark)

    Spilak, Michal; Kolarik, Barbara; Gunnarsen, Lars

    2012-01-01

    International field studies have documented that indoor air quality is unsatisfactory in many buildings. The overall hypothesis of this project is that improving the indoor environment in dwellings can improve health and reduce suffering from indoor related diseases such as allergy and asthma...... that have shown a marked increase in incidence all around the world during last decades. The purpose of this study is to investigate the effect of increased ventilation and expected lower exposure to house dust mites on symptoms and medication intake among asthmatic children. This will be done by installing...... balanced mechanical ventilation systems in 80 single-family houses. Half of the houses will be equipped with an effective ventilation system increasing air change rates from normal to approximately 3 h-1. A fake ventilation system will be installed in the other half of the houses. Primary subjects...

  9. Dose-Dependent Immunological Responses after a 6-Month Course of Sublingual House Dust Mite Immunotherapy in Patients with Allergic Rhinitis.

    Science.gov (United States)

    Didier, Alain; Campo, Paloma; Moreno, Francisco; Durand-Perdriel, François; Marin, Alicia; Chartier, Antoine

    2015-01-01

    House dust mite (HDM) immunotherapy has proven efficacy in treating allergic rhinitis (AR) symptoms. This trial evaluated the dose-response relationship of SLIToneULTRA® HDM mix based on immunological parameters and safety in subjects with moderate-to-severe HDM AR not controlled by symptomatic medication. A randomized, parallel-group, open-label, clinical trial compared 50/150/300 standard reactivity unit (SRU) doses of SLIToneULTRA® HDM mix for 6 months. Subjects had moderate-to-severe HDM AR, positive skin prick and IgE against Dermatophagoides pteronyssinus/Dermatophagoides farinae (DP/DF). The primary end point was change from baseline in the IgE-blocking factor against DP after 6 months. Secondary end points measured changes in the IgE-blocking factor for DP at 3 months and for DF at 3 and 6 months, and in IgG4 and specific IgE to DP/DF after 3 and 6 months. Tolerability was assessed through the evaluation of all adverse events (AEs). A total of 219 subjects were randomized and 196 completed the trial. Dose effect was significant on DP IgE-BF after 6 months (p = 0.018). The change in the DP IgE-blocking factor at a 300-SRU dose was higher than at other doses after 3 (p = 0.008) and 6 (p = 0005) months of treatment. Similar changes were observed for IgG4 and allergen-specific IgE. The number of AEs increased with the dose and were mild-to-moderate, with no severe treatment-related AEs reported. The most frequent AEs were oral/tongue pruritus, mouth oedema and abdominal upper pain. Data showed a dose-response for immunological markers and safety with a better immunological response for 300 SRU. The highest dose (300 SRU daily) was considered as the optimal maintenance dose. © 2016 The Author(s) Published by S. Karger AG, Basel.

  10. Limiting factors for growth and development of domestic mites

    NARCIS (Netherlands)

    Lynden, A.M.T. van; Kort, H.S.M.; Koren, L.G.H.; Pernot, C.E.E.; Bronswijk, J.E.M.H. van

    1996-01-01

    A quarter to half of European households are at risk of health damage due to mites in their home. House dust mites (family Pyroglyphidae) and storage mites (families Acaridae and Gly-cyphagidae) are present; both groups being specific for different ecosystems: house-dust ecosystem of textiles (house

  11. Evaluation of skin sensitivity in dogs bearing allergic dermatitis to standardized allergenic extract of house dust and storage mites Avaliação da sensibilidade de cães com dermatite alérgica a extratos padronizados de ácaros da poeira domiciliar

    National Research Council Canada - National Science Library

    Victor E.S. Cunha; Ruppert L. Hahnstadt; Ana Maria B. Soares; João Luiz H. Faccini

    2007-01-01

    The objective of the study was to evaluate whether allergenic extracts of five house dust and storage mite species standardized for humans might be used for the diagnosis of canine atopic dermatitis (CAD...

  12. Lunar Dust Contamination Effects on Lunar Base Thermal Control Systems

    Science.gov (United States)

    Keller, John R.; Ewert, Michael K.

    2000-01-01

    Many studies have been conducted to develop a thermal control system that can operate under the extreme thermal environments found on the lunar surface. While these proposed heat rejection systems use different methods to reject heat, each system contains a similar component, a thermal radiator system. These studies have always considered pristine thermal control system components and have overlooked the possible deleterious effects of lunar dust contamination. Since lunar dust has a high emissivity and absorptivity (greater than 0.9) and is opaque, dust accumulation on a surface should radically alter its optical properties and therefore alter its thermal response compared to ideal conditions. In addition, the non-specular nature of the dust particles will alter the performance of systems that employ specular surfaces to enhance heat rejection. To date, few studies have examined the effect of dust deposition on the normal control system components. These studies only focused on a single heat rejection or photovoltaic system. These studies did show that lunar dust accumulations alter the optical properties of any lunar base hardware, which in turn affects component temperatures, and heat rejection. Therefore, a new study was conducted to determine the effect of lunar dust contamination on heat rejection systems. For this study, a previously developed dust deposition model was incorporated into the Thermal Synthesizer System (TSS) model. This modeling scheme incorporates the original method of predicting dust accumulation due to vehicle landings by assuming that the thin dust layer can be treated as a semitransparent surface slightly above and in thermal contact with the pristine surface. The results of this study showed that even small amounts of dust deposits can radically alter the performance of the heat rejection systems. Furthermore. this study indicates that heat rejection systems be either located far from any landing sites or be protected from dust

  13. The different modes of binding of the dust mite allergens, Der f 7 and Der p 7, on a monoclonal antibody WH9 contribute to the differential reactivity.

    Science.gov (United States)

    Tai, Hsiao-Yun; Zhou, Jia-Kai; Yeh, Chang-Ching; Tam, Ming F; Sheu, Sheh-Yi; Shen, Horng-Der

    2017-06-28

    Der f 7 and Der p 7 are important house dust mite allergens. An IgE-binding inhibition monoclonal antibody WH9 reacts ten folds stronger against Der p 7 than to Der f 7. The purpose of this study is to identify the antigenic determinant(s) and the structural basis of Der f 7 recognize by WH9. WH9-reactive determinant(s) on Der f 7 was identified by immunoblot and immunoblot inhibition. The 3-D binary complex structures of WH9 and the group 7 allergens were simulated with homology modeling and docking methods. WH9 reacted with the Der f 7 f9 fragment. Among the five site-directed Der f 7 mutants, WH9 showed reduced immunoblot reactivity against Der f 7 S156A, D159A and P160A mutants. Only the wild-type protein and the Der f 7 I157A and L158A mutants can inhibit significantly the WH9-binding against Der f 7. The structural model of the Der f 7-WH9 complex suggests residues S156 and D159 of Der f 7 can bind to WH9 via potential hydrogen bonds. The structure models of Der f 7-WH9 and Der p 7-WH9 complexes revealed that the differential modes of binding of Der p 7 and Der f 7 allergens on WH9 contribute to the differential reactivity of WH9 against the Der f 7 and the Der p 7 mite allergens. Copyright © 2017. Published by Elsevier B.V.

  14. [Ecological study of Pyroglyphides mites in house dust in the Grenoble area. A qualitative approach and incidence of various parameters: seasons, altitude, temperature and relative dampness in their multiplication].

    Science.gov (United States)

    Lascaud, D

    1978-01-01

    This study concerns the analysis of 70 samples of dust mites taken periodically from 13 sample areas or mattresses at different altitudes. It shows the presence of Pyroglyphid mites in all the mattresses studied. Four species were found: Dermatophagoides pteronyssinus, Dermatophagoides farinae, Euroglyphus maynei and Dermatophagoides evansi. From a quantitative point of view, the statistical analysis of the results obtained allows the following conclusions to be drawn: -- All the Pyroglyphids (adults and young) undergo seasonal fluctuations at low, middle and high altitude. In the plains and at middle altitude these mites have a seasonal maximum and minimum. At high altitude only the seasonal maximum can be determined. -- The number of Pyroglyphids found is much higher in the plaine than at middle altitude and at middle altitude than at high altitude. The influence of altitude can be demonstrated with certitude. -- The conditions of temperature and relative dampness most favourable to the multiplication of mites are found in the plaine. At middle and high altitude these conditions are only met in summer. In flat country the statistical analysis allows us to show the existance of a correlation between the rate of dampness and the number of Pyroglyphids, and more specially, between the dampness rate and Dermatophagoides farinae, a predominant species at this sampling area. At middle and high altitude such a correlation cannot be shown clearly. At the three altitudes considered, no correlation can be established between the temperature and the number of Pyroglyphid mites found.

  15. 30 CFR 72.630 - Drill dust control at underground areas of underground mines.

    Science.gov (United States)

    2010-07-01

    ... dust control at underground areas of underground mines. (a) Dust resulting from drilling in rock shall... condition. Dust collectors approved under Part 33—Dust Collectors for Use in Connection with Rock Drilling... the purpose of this section. (c) Water control. Water used to control dust from drilling rock shall...

  16. House dust mite major allergens Der p 1 promote the production of IL-8 and MUC5AC in human airway-derived epithelial cells by NF-kB mechanism

    Institute of Scientific and Technical Information of China (English)

    Renping Liu; Qi Hou; and Aiming Meng

    2012-01-01

    Backgroud: House dust mite allergens (HDM) is the most commonly encountered patho- gen of humans, predominantly causing bronchoconstriction in asthma patients and inducing an inflammatory response in the lungs dune to the release of cytokines, chemokines and other medi- ators. During the clinical course of treatment, dexamethasone has a limited effect on asthma pa- tients, especially for refractory asthma, because it is infective to block a large number of theneutrophils to invade the lung tissue.

  17. SPARCLE: Electrostatic Dust Control Tool Proof of Concept

    Science.gov (United States)

    Clark, P. E.; Curtis, S. A.; Minetto, F.; Marshall, J.; Nuth, J.; Calle, C.

    2010-01-01

    Successful exploration of most planetary surfaces, with their impact-generated dusty regoliths, will depend on the capabilities to keep surfaces free of the performance-compromising dust. Once in contact with surfaces, whether set in motion by natural or mechanical means, regolith fines, or dust, behave like abrasive Velcro, coating surfaces, clogging mechanisms, making movement progressively more difticult, and being almost impossible to remove by mechanical mcans (brushing). The successful dust removal strategy will deal with dust dynamics resulting from interaction between Van der Waals and Coulombic forces. Here, proof of concept for an electrostatically-based concept for dust control tool is described and demonstrated. A low power focused electron beam is used in the presence of a small electrical field to increase the negative charge to mass ratio of a dusty surface until dust repulsion and attraction to a lower potential surface, acting as a dust collector, occurred. Our goal is a compact device of less than 5 kg mass and using less than 5 watts of power to be operational in less than 5 years with heritage from ionic sweepers for active spacecraft potential control (e.g ., on POLAR). Rovers could be fitted with devices that could hamess the removal of dust for sampling as part of the extended exploration process on Mercury, Mars, asteroids or outer solar system satellites, as well as the Moon.

  18. SPARCLE: Electrostatic Dust Control Tool Proof of Concept

    Science.gov (United States)

    Clark, P. E.; Curtis, S. A.; Minetto, F.; Marshall, J.; Nuth, J.; Calle, C.

    2010-01-01

    Successful exploration of most planetary surfaces, with their impact-generated dusty regoliths, will depend on the capabilities to keep surfaces free of the performance-compromising dust. Once in contact with surfaces, whether set in motion by natural or mechanical means, regolith fines, or dust, behave like abrasive Velcro, coating surfaces, clogging mechanisms, making movement progressively more difticult, and being almost impossible to remove by mechanical mcans (brushing). The successful dust removal strategy will deal with dust dynamics resulting from interaction between Van der Waals and Coulombic forces. Here, proof of concept for an electrostatically-based concept for dust control tool is described and demonstrated. A low power focused electron beam is used in the presence of a small electrical field to increase the negative charge to mass ratio of a dusty surface until dust repulsion and attraction to a lower potential surface, acting as a dust collector, occurred. Our goal is a compact device of less than 5 kg mass and using less than 5 watts of power to be operational in less than 5 years with heritage from ionic sweepers for active spacecraft potential control (e.g ., on POLAR). Rovers could be fitted with devices that could hamess the removal of dust for sampling as part of the extended exploration process on Mercury, Mars, asteroids or outer solar system satellites, as well as the Moon.

  19. Aceria kuko Mites: a Comprehensive Review of Their Phytosanitary Risk, Pathways and Control

    Directory of Open Access Journals (Sweden)

    Roxana Ciceoi

    2016-11-01

    Full Text Available The present review aims to identify the phytosanitary risk, the pathways and the possible control methods of a new eryophid alien species mentioned for the first time in Romania in 2010. The pest is Aceria kuko, the goji-berries gall mite, imported in Europe from China via orders by mail possibly in 2007 or 2008. Although the import from third countries into the European Union of Solanaceae intended for planting is prohibited according to Dir. 2000/29/EC, as a protective measure against the introduction into the Community of organisms harmful to plants or plant products and against their spread within the Community, the parcels ordered by mail escape the quarantine and pest & disease control services. Our field observations regarding the attack frequency, attack intensity and the losses indicate that the non-native plant pest is a potential threat also for Romania, although no attention has been given to it until the present moment. We consider that monitoring the presence of the mite in the Romanian Goji plantations and the changes in the A. kuko biology and ecology has a strategic importance and should be regarded as a biosafety measure not only for Romania, but for entire Europe, as the Goji fruits produced in Romania are mainly exported in the European countries.

  20. Analysis of efficacy and safety of standardized dust mites allergen vaccine in treatment of allergic rhinitis%标准化尘螨变应原治疗变应性鼻炎的疗效及安全性分析

    Institute of Scientific and Technical Information of China (English)

    桂晓钟; 纪东; 程静; 赵军; 王林; 蒋传亚

    2012-01-01

    of single dust mite allergy patients was much better than patients with dust mite allergy consisting mainly of diversified allergens, and the proportion of the obvious treatment efficacy on the former was 78. 38% , and that of the latter was just 40. 38% . Conclusion Standardized allergen specific immunotherapy is an effective and safe treatment method for patients suffering from allergic rhinitis caused by house - dust mites, and it may effectively control the symptom of asthma to some extent.

  1. The determinants of dust mite allergen and its relationship to the prevalence of symptoms of asthma in the Asia-Pacific region.

    Science.gov (United States)

    Wickens, Kristin; de Bruyne, Jessie; Calvo, Mario; Choon-Kook, Sam; Jayaraj, G; Lai, Christopher K W; Lane, Juliette; Maheshwari, Rameshchandra; Mallol, Javier; Nishima, Sankei; Purdie, Gordon; Siebers, Rob; Sukumaran, Thevaruparambil; Trakultivakorn, Muthita; Crane, Julian

    2004-02-01

    The role that house dust mites play in the primary causation of asthma is controversial. Approximately thirty-six 10-yr-old children in each of 10 centres in the Asia-Pacific region participated. Researchers collected dust from mattresses and living room floors using standardized procedures. Der p1 and Der f1 were analysed using a double monoclonal antibody enzyme-linked immunosorbent assay. Geometric mean allergen levels were calculated for each centre. An ecological analysis was conducted to show the regression of the geometric mean allergen level, using the highest household level, against asthma symptom and severity prevalence data from the International Study of Asthma and Allergies in Childhood, Phase I. Among children aged 13-14 yr, the change in asthma symptom prevalence was associated with per unit change in Der p1 microg/g (1.08, 95% CI 0.10-2.06) and Der 1 microg/g (Der p1 + Der f1) (0.64, 95% CI 0.02-1.26). The change in having four or more attacks of asthma in the last 12 months was associated with per unit change in Der p 1 microg/g (0.29, 95% CI -0.02 to 0.60) and Der 1 microg/g (0.20, 95% CI 0.01-0.38). There was no effect for total Der p1 or Der f1 (total or microg/g). Among children aged 6-7 yr, neither allergen was related to symptoms or severity prevalence. While our findings suggest that Dermatophagoides pteronyssinus may have a role in the primary causation of asthma, the complexity of this association reinforces the need for prospective studies.

  2. Effective dust control systems on concrete dowel drilling machinery.

    Science.gov (United States)

    Echt, Alan S; Sanderson, Wayne T; Mead, Kenneth R; Feng, H Amy; Farwick, Daniel R; Farwick, Dawn Ramsey

    2016-09-01

    Rotary-type percussion dowel drilling machines, which drill horizontal holes in concrete pavement, have been documented to produce respirable crystalline silica concentrations above recommended exposure criteria. This places operators at potential risk for developing health effects from exposure. United States manufacturers of these machines offer optional dust control systems. The effectiveness of the dust control systems to reduce respirable dust concentrations on two types of drilling machines was evaluated under controlled conditions with the machines operating inside large tent structures in an effort to eliminate secondary exposure sources not related to the dowel-drilling operation. Area air samples were collected at breathing zone height at three locations around each machine. Through equal numbers of sampling rounds with the control systems randomly selected to be on or off, the control systems were found to significantly reduce respirable dust concentrations from a geometric mean of 54 mg per cubic meter to 3.0 mg per cubic meter on one machine and 57 mg per cubic meter to 5.3 mg per cubic meter on the other machine. This research shows that the dust control systems can dramatically reduce respirable dust concentrations by over 90% under controlled conditions. However, these systems need to be evaluated under actual work conditions to determine their effectiveness in reducing worker exposures to crystalline silica below hazardous levels.

  3. Potential of the mite-pathogenic fungus Neozygites floridana (Entomophthorales: Neozygitaceae) for control of the cassava green mite Mononychellus tanajoa (Acari: Tetranychidae).

    Science.gov (United States)

    Elliot, S L; de Moraes, G J; Delalibera, I; da Silva, C A; Tamai, M A; Mumford, J D

    2000-06-01

    The cassava green mite, Mononychellus tanajoa (Bondar), is an exotic pest in Africa and is the target of a classical biological control programme. Field data from the Neotropics, where it is indigenous, are presented for the first time, charting the variation in abundance of M. tanajoa over several seasons. This was highly variable, with a characteristic trough mid-year and a peak at the turn of the year. This pattern corresponded positively with rainfall levels, appearing to fit a phenology also characteristic of African studies, where rainfall at the start of the wet season promotes a leaf flush and so growth in M. tanajoa populations. Analyses implied some impact of leaf-inhabiting predatory mites (predominantly Neoseiulus idaeus Denmark & Muma) and a considerable impact of the fungal pathogen Neozygites floridana Fisher on M. tanajoa populations. This pathogen was not observed in the host population for several (generally dry) periods implying survival outside the host, perhaps as resting spores. This is a particularly desirable characteristic of a biological control agent. It is therefore proposed that N. floridana might be of particular use in drier cassava-growing areas where rainfall at the outset of the wet season is not sufficiently intense to cause heavy M. tanajoa mortality but may be sufficient to stimulate epizootics of the fungal pathogen, protecting the flush of new cassava growth.

  4. Nasal sodium cromoglycate (Lomusol) modulates the early phase reaction of mild to moderate persistent allergic rhinitis in patients mono-sensitized to house dust mite: a preliminary study.

    Science.gov (United States)

    Lejeune, Margaux; Lefebvre, Philipe P; Delvenne, Philippe; El-Shazly, Amr E

    2015-05-01

    We evaluated the clinical improvement of patients with mild to moderate persistent allergic rhinitis (AR) due to mono-sensitization to house dust mite (HDM) allergen, by sodium cromoglycate nasal spray (Lomusol 4%). Lomusol was used as a single agent treatment, and its anti-inflammatory effects, in the early phase reaction were evaluated. Herein we showed that Lomusol significantly improved the subjective nasal symptom scores especially nasal obstruction. This was associated with significant and specific reduction in neutrophils influx in nasal cytology but had no effect on other cell types. This selective anti-inflammatory effect on nasal cytology was associated with significant reduction in the levels of platelet activating factor (PAF) and histamine in nasal secretions but had no effect on PGD2, LTC4 or CysLt levels. Lomusol was also able to induce significant reduction in eosinophil cationic protein (ECP) levels in nasal secretions without altering the percentage of eosinophil influx in nasal cytology. Taken collectively, we showed the first evidence that nasal sodium cromoglycate possesses a selective inhibition on neutrophil recruitment into nasal cytology in the early phase reaction of AR patients mono-sensitized to HDM. This may be attributed to the ability of Lomusol to significantly reduce the amount of PAF recovered in nasal secretion. These results were associated with significant improvement in subjective symptom scores especially nasal obstruction that may in addition, be due to the ability of Lomusol to down-regulate eosinophil degranulation activity as well.

  5. Enhanced Cysteinyl-Leukotriene Type 1 Receptor Expression in T Cells from House Dust Mite-Allergic Individuals following Stimulation with Der p

    Directory of Open Access Journals (Sweden)

    Maryse Thivierge

    2015-01-01

    Full Text Available In order to determine the potential for allergen to modulate T cell expression of the CysLT1 receptor and responsiveness to leukotrienes, peripheral blood mononuclear cells from house dust mite-allergic or nonallergic individuals were incubated with D. pteronyssinus allergen (Der p. Baseline CysLT1 expression was similar in both groups of donors, but Der p significantly enhanced CysLT1 expression in CD4+ and CD8+ T cells of only allergic individuals and induced enhanced responsiveness of CD4+ T cells to LTD4 in terms of calcium mobilisation. This effect was prevented by the CysLT1 antagonist MK571. Der p also induced IL-4 and IL-10 production, and neutralizing antibody to IL-4 prevented both the enhanced CysLT1 expression and the enhanced responsiveness of T cells to LTD4 induced by Der p. In allergic individuals, Der p also induced T cell proliferation and a Th2-biased phenotype. Our data suggest that, in allergen-sensitized individuals, exposure to allergen can enhance T cell expression of CysLT1 receptors through a mechanism involving IL-4 production. This, in turn, would induce CD4+ T cell responsiveness to cysteinyl-leukotrienes and Th2 cell activation.

  6. The Hot-Water Extract of Smilacis Chinae Rhizome Suppresses 2,4-Dinitrochlorobenzene and House Dust Mite-Induced Atopic Dermatitis-Like Skin Lesions in Mice.

    Science.gov (United States)

    Ki, Nam Yong; Park, Eun-Ji; Sung, In sung; Ju, Seul A; Kim, Kyoung Un; Kim, Mi Rae; Song, Do Yeon; Lee, Min-Ju; Kim, Hak-Soo; Kang, Boo-Hyon; Chung, Hun-Jong; Choi, Eun-Ju; Yoon, Ki-Hun; Lee, Min Won; Yun, Seongho; Min, Bokkee; Kwon, Suk Hyung; Shin, Hwa-Sup

    2016-04-01

    Smilacis Chinae Rhizome (SCR) has been used as an oriental folk medicine for various biological activities. However, its effect on atopic dermatitis (AD) remains undetermined to date. We assessed the effect of orally administered hot-water extract of SCR on AD-like skin lesions in mice and its underlying mechanisms. AD-like murine model was prepared by repeated alternate application of house dust mite (Dermatophagoides farinae) extract (DFE) and 2,4-dinitrochlorobenzene (DNCB) for 4 weeks, topically to the ears. Daily oral administration of SCR for 3 and 4 weeks significantly reduced inflammatory ear thickening, with the effect being enhanced at the earlier start and longer period of administration. This effect was accompanied by a significant decrease in both Th2 and Th1 serum antibodies (total IgE, DFE-specific IgE, and IgG2a). Histological analysis showed that SCR markedly decreased the epidermal/dermal ear thickening and the dermal infiltration of inflammatory cells. Furthermore, SCR suppressed DFE/DNCB-induced expression of IL-4, IL-13, IL-17, IL-18, TSLP, and IFN-γ genes in the ear tissue. Taken together, our observations demonstrate that chronic oral administration of SCR exerts beneficial effect in mouse AD model, suggesting that SCR has the therapeutic potential as an orally active treatment of AD by modulating both Th1 and Th2 responses.

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

    Science.gov (United States)

    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.

  8. Repetitive Immunoassay with a Surface Acoustic Wave Device and a Highly Stable Protein Monolayer for On-Site Monitoring of Airborne Dust Mite Allergens.

    Science.gov (United States)

    Toma, Koji; Miki, Daisuke; Kishikawa, Chisato; Yoshimura, Naoyuki; Miyajima, Kumiko; Arakawa, Takahiro; Yatsuda, Hiromi; Mitsubayashi, Kohji

    2015-10-20

    This work describes a sensor to be incorporated into the on-site monitoring system of airborne house dust mite (HDM) allergens. A surface acoustic wave (SAW) device was combined with self-assembled monolayers of a highly stable antibody capture protein on the SAW surface that have high resistance to pH change. A sandwich assay was used to measure a HDM allergen, Der f 1 derived from Dermatophagoides farinae. Capture antibodies were cross-linked to a protein G based capture layer (ORLA85) on the sensor surface, thereby only Der f 1 and detection antibodies were regenerated by changing pH, resulting in fast repetition of the measurement. The sensor was characterized through 10 repetitive measurements of Der f 1, which demonstrated high reproducibility of the sensor with the coefficient of variation of 5.6%. The limit of detection (LOD) of the sensor was 6.1 ng·mL(-1), encompassing the standard (20 ng·mL(-1)) set by the World Health Organization. Negligible sensor outputs were observed for five different major allergens including other HDM allergens which tend to have cross-reactivity to Der f 1 and their mixtures with Der f 1. Finally, the sensor lifetime was evaluated by conducting three measurements per day, and the sensor output did not substantially change for 4 days. These characteristics make the SAW immunosensor a promising candidate for incorporation into on-site allergen monitoring systems.

  9. Control of the northern fowl mite on inanimate objects by fumigation: laboratory studies.

    Science.gov (United States)

    Beerwinkle, K R; Devaney, J A

    1983-01-01

    Laboratory studies were conducted to determine the efficacies of phosphine, methyl bromide, and sulfur dioxide as fumigants for the northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), on inanimate objects. We were able to demonstrate that either methyl bromide or sulfur dioxide could kill all physiological forms of mites within 24 hr, which would be desirable for field use. Prosphine gas, released from Phostoxin pellets, had an LD95 of 18 hr for motile forms of the mites; however, it took 30 hr to kill the mite eggs. Therefore, it would be an unsuitable fumigant for practical field usage.

  10. Group 1 Allergen Genes in Two Species of House Dust Mites, Dermatophagoides farinae and D. pteronyssinus (Acari: Pyroglyphidae: Direct Sequencing, Characterization and Polymorphism.

    Directory of Open Access Journals (Sweden)

    Rubaba Hamid Shafique

    Full Text Available Group 1 allergens of Dermatophagoides farinae (Der f 1 and D. pteronyssinus (Der p 1 dominate overall allergic responses in house dust mite allergy patients. The need for accurate identification and characterization of representative variants of group 1 allergens in any given geographic locality has been emphasized for development of appropriate allergen extracts. Regional amino acid sequence polymorphism has been described but the extent of this polymorphism is not well understood. Such data are completely absent for the USA and many other countries. Most previous studies used cDNA libraries generated by reverse transcriptase (RT-PCR and/or primers amplifying shorter fragments of this gene. Using novel species-specific primers and direct PCR, we document group 1 allergen gene sequence polymorphism in populations of D. farinae and D. pteronyssinus from the USA and Pakistan. We report two novel introns (nt pos 87 and 291 in both species, and the absence of intron 3 in Der p 1. Thirteen silent and one novel non-synonymous mutation (Tryptophan W197 to Arginine R197 were detected in D. farinae. The potential medical significance of the latter mutation is discussed. Two haplotypes of the Der f 1 gene were identified, haplotype 1 (63% was more frequent than haplotype 2 (18%. Polymorphism in Der f 1 displayed geographical localization, since both haplotypes were present in mite populations from Pakistan whereas haplotype 1 was observed only in the USA. In Der p 1, a silent mutation at nt (aa position 1011(149 and four non-synonymous mutations at positions 589(50, 935(124, 971(136, 1268(215 were observed. These mutations were reported from many other geographic regions, suggesting that polymorphism in the Der p 1 gene is panmictic. The extent of polymorphism in both genes is substantially lower than that reported previously (0.10-0.16% vs 0.31-0.49%, indicating the need for careful evaluation of potential polymerase errors in studies utilizing RT-PCR.

  11. Biology and control of Eriophyid mites with a case study of Aceria sp. on New Mexico olive (Forestiera pubescens Nutt. var. pubescens)

    Science.gov (United States)

    Tessa R. Grasswitz

    2012-01-01

    The biology, recognition, and impact of eriophyid mites (with emphasis on species associated with trees and shrubs) are briefly reviewed. A case study of a leaf-curling eriophyid mite (Aceria sp.) attacking New Mexico olive (Forestiera pubescens Nutt. var. pubescens) is used to illustrate the complexities of developing control strategies for eriophyids in native plant...

  12. The economic importance of acaricides in the control of phytophagous mites and an update on recent acaricide mode of action research

    NARCIS (Netherlands)

    Van Leeuwen, T.; Tirry, L.; Yamamoto, A.; Nauen, R.; Dermauw, W.

    2015-01-01

    Acaricides are one of the cornerstones of an efficient control program for phytophagous mites. An analysis of the global acaricide market reveals that spider mites such as Tetranychus urticae, Panonychus citri and Panonychus ulmi are by far the most economically important species, representing more

  13. Controlling strongly correlated dust clusters with lasers

    CERN Document Server

    Thomsen, Hauke; Bonitz, Michael; Schablinski, Jan; Block, Dietmar; Schella, André; Melzer, André

    2014-01-01

    The most attractive feature of dusty plasmas is the possibility to create strong correlations at room temperatures. At the same time, these plasmas allow for a precise diagnostics with single-particle resolution. From such measurements, the structural properties of finite two-dimensional (2D) clusters and three-dimensional (3D) spherical crystals in nearly harmonic traps-Yukawa balls-have been explored in great detail. Their structural properties-the shell compositions and the order within the shells-have been investigated and good agreement to theoretical predictions was found. Open questions on the agenda are the excitation behavior, the structural changes, and phase transitions that occur at elevated temperature. In order to increase the dust temperature in the experiment various techniques have been used. Among them, laser heating appears to have unique capabilities because it affects only the dust particles, leaving the lighter plasma components unchanged. Here we report on recent experimental results wh...

  14. Selection and characterization of Beauveria spp. isolates to control the broad mite Polyphagotarsonemus latus (Banks, 1904 (Acari: Tarsonemidae

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    C. C. Martins

    Full Text Available Abstract This study was performed under laboratory conditions to identify isolates of the fungus Beauveria spp. that can control Polyphagotarsonemus latus in the greenhouse and field. Thirty Beauveria spp. isolates were tested by spraying 1 mL conidia (1 × 108 conidia/mL on pepper leaf discs containing 15 mites. Evaluations were performed on the 3rd and 6th day post application by counting the number of dead mites. Vegetative growth and conidial production were measured from the selected isolates, and bioassays were conducted in the greenhouse on bean seedlings in plastic pots. The isolate Unioeste 53 was selected, and a conidial suspension (1 × 108 conidia/mL was applied with a backpack sprayer. The evaluation consisted of pre- and post-treatment counts of the number of live mites on ten leaflets in both the plots treated with the fungus and control plots, and the same procedure was followed for the field experiment. In the laboratory, the Unioeste 53 isolate resulted in total and confirmed mortality rates of 70% and 57.7%, respectively. In the greenhouse, the population decreased by 76.71% by the 16th day after application. In the field, the population decreased by 66% by the 12th day after application, demonstrating the potential of this fungus for mite management.

  15. Clinical efficacy of a standardized specific immunotherapy against house dust mite in 85 asthmatic children%尘螨标准化免疫治疗85例哮喘儿童疗效相关指标分析

    Institute of Scientific and Technical Information of China (English)

    张璇; 李孟荣; 王超; 王晓宁; 张海邻; 林剑; 金可; 李迎春

    2010-01-01

    , total IgE, specific IgE, peak expiratory flow rate (PEF), etc. during a standardized SIT against house dust mite in allergic asthmatic children. Method Children (5-13 years old) with mild to moderate allergic asthma seen from February 2005 to June 2008 were enrolled into this study. A non- randomized retrospective study was performed. All children were diagnosed sensitive to dust mites, the treatment group accepted standardized dust mite allergen specific immunotherapy. Each fourth injections were defined as observation points, the study took 3.4 years. The investigators recorded the treatment, the cumulative allergen extract, changes of daffy doses of inhaled corticosteroid, peak expiratory flow (PEF), total IgE (TIgE), specific IgE (SIgE). The control group only received inhaled corticosteroids. The daily doses of inhaled corticosteroid and the number of asthma attacks,and the control rate were compared between the 2 groups. Result Totally 85 children were treated with SIT [(7.6 ± 1.4) years], 45 males and 40 females; 50 children received only drug treatment [(7.7 ± 1.5)years], 28 males and 22 females. The cumulative dose of allergen was up to (69.7 ± 4.8) μg after the 20 times injection, the dose of inhaled corticosteroids was significantly less than that in the control group ( t =2. 359, P < 0.05). PEF was significantly higher than that of pre-treatment level ( F = 7.874, P < 0.05 ).TIgE and SIgE had no significant change (t = 0.313, P > 0.05, tDerp = 0.517, tDerf = 0.717,P > 0.05 ). After the treatment, the control rate of the SIT group was 85.5%, that of the control group was 62.0% (X2 =10.150, P <0.01). Conclusion The standardized SIT against house dust mite could reduce steroid use in mild to moderate allergic asthmatic children. After ( 38.7± 2.3 ) weeks, the cumulative dose of allergen was up to (69.7 + 4.8) μg, inhaled corticosteroid was significantly reduced. At the end of SIT, 85% of patients obtained complete control of asthma. Total Ig

  16. Real-Life Study for the Diagnosis of House Dust Mite Allergy - The Value of Recombinant Allergen-Based IgE Serology.

    Science.gov (United States)

    Becker, Sven; Schlederer, Thomas; Kramer, Matthias F; Haack, Mareike; Vrtala, Susanne; Resch, Yvonne; Lupinek, Christian; Valenta, Rudolf; Gröger, Moritz

    2016-01-01

    Dermatophagoides pteronyssinus is one of the most important perennial allergen sources worldwide. Molecular diagnostics using the commercially available major allergens (Der p 1 and Der p 2) in combination with Der p 10 do not detect house dust mite (HDM) sensitization in a number of cases when used alone. The objective was to evaluate the IgE reactivity profiles of these patients using an experimental immunoassay biochip. Sera of HDM-allergic patients (positive skin prick test, CAP class ≥1 for allergen extract, and positive intranasal provocation) were tested for IgE antibodies against Der p 1, Der p 2, and Der p 10 by ImmunoCAP fluorescence enzyme immunoassay. Negatively tested sera were examined by an experimental chip containing 13 microarrayed HDM allergens. Of 97 patients tested, 16 showed negative results to Der p 1, Der p 2, and Der p 10. MeDALL chip evaluation revealed 5 patients monosensitized to Der p 23, and 11 patients were negative for all HDM MeDALL chip components. Seven sera were available for further testing, and 3 of them showed IgE reactivity to dot-blotted nDer p 1, and 2 reacted with high-molecular weight components (>100 kDa) in nitrocellulose-blotted HDM extract when tested with 125I-labeled anti-IgE in a RAST-based assay. The HDM extract-specific IgE levels of the 11 patients were <3.9 kU/l. Recombinant allergen-based IgE serology is of great value when conventional IgE diagnostics fails. Der p 23 is an important HDM allergen, especially when major allergens are negative. Therefore, it would be desirable to have Der p 23 commercially available. Further research concerning the prevalence and clinical significance of different HDM allergens is needed. © 2016 S. Karger AG, Basel.

  17. IgE Abs to Der p 1 and Der p 2 as diagnostic markers of house dust mite allergy as defined by a bronchoprovocation test.

    Science.gov (United States)

    Minami, Takafumi; Fukutomi, Yuma; Lidholm, Jonas; Yasueda, Hiroshi; Saito, Akemi; Sekiya, Kiyoshi; Tsuburai, Takahiro; Maeda, Yuji; Mori, Akio; Taniguchi, Masami; Hasegawa, Maki; Akiyama, Kazuo

    2015-01-01

    Limited information is available regarding the clinical usefulness of measuring the levels of IgE to allergen components from house dust mites (HDMs) in the diagnosis of genuine HDM allergy. To evaluate the diagnostic usefulness of measuring levels of serum IgE antibodies (Abs) to allergen components from Dermatophagoides pteronyssinus (DP) as a predictor of immediate asthmatic response (IAR) to bronchoprovocation, we studied 55 DP-sensitized asthmatic patients who underwent a bronchoprovocation test using crude DP extract. The levels of IgE Abs to crude DP, nDer p 1, rDer p 2, and rDer p 10 in patients who showed IAR (n = 41) were compared with those in patients who showed no IAR (n = 14). While the frequencies of positivity for IgE Abs to nDer p 1 and rDer p 2 among the entire study population were 89 and 86%, respectively, all patients with IAR tested positive for both of them with high IgE concentrations. The areas under the receiver operating characteristic curves for IgE to nDer p 1 and rDer p 2 as predictors of IAR were 0.913 and 0.906, respectively. The specificity of IgE to nDer p 1 and rDer p 2 was higher than IgE to crude DP even at low cut-off points. IgE to nDer p 1 and/or rDer p 2 was highly predictive of allergen-induced IAR. These findings validate the clinical usefulness of measuring the levels of IgE to nDer p 1 and rDer p 2 as a diagnostic tool for genuine HDM allergy. Copyright © 2014 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

  18. Neutralization of TSLP inhibits airway remodeling in a murine model of allergic asthma induced by chronic exposure to house dust mite.

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    Zhuang-Gui Chen

    Full Text Available Chronic allergic asthma is characterized by Th2-typed inflammation, and contributes to airway remodeling and the deterioration of lung function. However, the initiating factor that links airway inflammation to remodeling is unknown. Thymic stromal lymphopoietin (TSLP, an epithelium-derived cytokine, can strongly activate lung dendritic cells (DCs through the TSLP-TSLPR and OX40L-OX40 signaling pathways to promote Th2 differentiation. To determine whether TSLP is the underlying trigger of airway remodeling in chronic allergen-induced asthma, we induced allergic airway inflammation in mice by intranasal administration of house dust mite (HDM extracts for up to 5 consecutive weeks. We showed that repeated respiratory exposure to HDM caused significant airway eosinophilic inflammation, peribronchial collagen deposition, goblet cell hyperplasia, and airway hyperreactivity (AHR to methacholine. These effects were accompanied with a salient Th2 response that was characterized by the upregulation of Th2-typed cytokines, such as IL-4 and IL-13, as well as the transcription factor GATA-3. Moreover, the levels of TSLP and transforming growth factor beta 1 (TGF-β1 were also increased in the airway. We further demonstrated, using the chronic HDM-induced asthma model, that the inhibition of Th2 responses via neutralization of TSLP with an anti-TSLP mAb reversed airway inflammation, prevented structural alterations, and decreased AHR to methacholine and TGF-β1 level. These results suggest that TSLP plays a pivotal role in the initiation and persistence of airway inflammation and remodeling in the context of chronic allergic asthma.

  19. Lung-homing of endothelial progenitor cells and airway vascularization is only partially dependant on eosinophils in a house dust mite-exposed mouse model of allergic asthma.

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    Nirooya Sivapalan

    Full Text Available Asthmatic responses involve a systemic component where activation of the bone marrow leads to mobilization and lung-homing of progenitor cells. This traffic may be driven by stromal cell derived factor-1 (SDF-1, a potent progenitor chemoattractant. We have previously shown that airway angiogenesis, an early remodeling event, can be inhibited by preventing the migration of endothelial progenitor cells (EPC to the lungs. Given intranasally, AMD3100, a CXCR4 antagonist that inhibits SDF-1 mediated effects, attenuated allergen-induced lung-homing of EPC, vascularization of pulmonary tissue, airway eosinophilia and development of airway hyperresponsiveness. Since SDF-1 is also an eosinophil chemoattractant, we investigated, using a transgenic eosinophil deficient mouse strain (PHIL whether EPC lung accumulation and lung vascularization in allergic airway responses is dependent on eosinophilic inflammation.Wild-type (WT BALB/c and eosinophil deficient (PHIL mice were sensitized to house dust mite (HDM using a chronic exposure protocol and treated with AMD3100 to modulate SDF-1 stimulated progenitor traffic. Following HDM challenge, lung-extracted EPCs were enumerated along with airway inflammation, microvessel density (MVD and airway methacholine responsiveness (AHR.Following Ag sensitization, both WT and PHIL mice exhibited HDM-induced increase in airway inflammation, EPC lung-accumulation, lung angiogenesis and AHR. Treatment with AMD3100 significantly attenuated outcome measures in both groups of mice. Significantly lower levels of EPC and a trend for lower vascularization were detected in PHIL versus WT mice.This study shows that while allergen-induced lung-homing of endothelial progenitor cells, increased tissue vascularization and development lung dysfunction can occur in the absence of eosinophils, the presence of these cells worsens the pathology of the allergic response.

  20. Airway inflammation and IgE production induced by dust mite allergen-specific memory/effector Th2 cell line can be effectively attenuated by IL-35.

    Science.gov (United States)

    Huang, Chiung-Hui; Loo, Evelyn Xiu-Ling; Kuo, I-Chun; Soh, Gim Hooi; Goh, Denise Li-Meng; Lee, Bee Wah; Chua, Kaw Yan

    2011-07-01

    CD4(+) memory/effector T cells play a central role in orchestrating the rapid and robust immune responses upon re-encounter with specific Ags. However, the immunologic mechanism(s) underlying these responses are still not fully understood. To investigate this, we generated an allergen (major house dust mite allergen, Blo t 5)-specific murine Th2 cell line that secreted IL-4, IL-5, IL-10, and IL-13, but not IL-9 or TNF-α, upon activation by the cognate Ag. These cells also exhibited CD44(high)CD62L(-) and CD127(+) (IL-7Rα(+)) phenotypes, which are characteristics of memory/effector T cells. Experiments involving adoptive transfer of this Th2 cell line in mice, followed by three intranasal challenges with Blo t 5, induced a dexamethasone-sensitive eosinophilic airway inflammation. This was accompanied by elevation of Th2 cytokines and CC- and CXC-motif chemokines, as well as recruitment of lymphocytes and polymorphic mononuclear cells into the lungs. Moreover, Blo t 5-specific IgE was detected 4 d after the last intranasal challenge, whereas elevation of Blo t 5-specific IgG1 was found at week two. Finally, pulmonary delivery of the pVAX-IL-35 DNA construct effectively downregulated Blo t 5-specific allergic airway inflammation, and i.m. injection of pVAX-IL-35 led to long-lasting suppression of circulating Blo t 5-specific and total IgE. This model provides a robust research tool to elucidate the immunopathogenic role of memory/effector Th2 cells in allergic airway inflammation. Our results suggested that IL-35 could be a potential therapeutic target for allergic asthma through its attenuating effects on allergen-specific CD4(+) memory/effector Th2 cell-mediated airway inflammation.

  1. An intranasal selective antisense oligonucleotide impairs lung cyclooxygenase-2 production and improves inflammation, but worsens airway function, in house dust mite sensitive mice

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    Pujols Laura

    2008-11-01

    Full Text Available Abstract Background Despite its reported pro-inflammatory activity, cyclooxygenase (COX-2 has been proposed to play a protective role in asthma. Accordingly, COX-2 might be down-regulated in the airway cells of asthmatics. This, together with results of experiments to assess the impact of COX-2 blockade in ovalbumin (OVA-sensitized mice in vivo, led us to propose a novel experimental approach using house dust mite (HDM-sensitized mice in which we mimicked altered regulation of COX-2. Methods Allergic inflammation was induced in BALBc mice by intranasal exposure to HDM for 10 consecutive days. This model reproduces spontaneous exposure to aeroallergens by asthmatic patients. In order to impair, but not fully block, COX-2 production in the airways, some of the animals received an intranasal antisense oligonucleotide. Lung COX-2 expression and activity were measured along with bronchovascular inflammation, airway reactivity, and prostaglandin production. Results We observed impaired COX-2 mRNA and protein expression in the lung tissue of selective oligonucleotide-treated sensitized mice. This was accompanied by diminished production of mPGE synthase and PGE2 in the airways. In sensitized mice, the oligonucleotide induced increased airway hyperreactivity (AHR to methacholine, but a substantially reduced bronchovascular inflammation. Finally, mRNA levels of hPGD synthase remained unchanged. Conclusion Intranasal antisense therapy against COX-2 in vivo mimicked the reported impairment of COX-2 regulation in the airway cells of asthmatic patients. This strategy revealed an unexpected novel dual effect: inflammation was improved but AHR worsened. This approach will provide insights into the differential regulation of inflammation and lung function in asthma, and will help identify pharmacological targets within the COX-2/PG system.

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

    Science.gov (United States)

    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 correlation with sIgE Dermatophagoides pteronyssinus and it can be used in CR patients with negative SPT where sIgE is not feasible.

  3. Innate immune response of alveolar macrophage to house dust mite allergen is mediated through TLR2/-4 co-activation.

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    Chia-Fang Liu

    Full Text Available House dust mite, Dermatophagoides pteronyssinus (Der p, is one of the major allergens responsible for allergic asthma. However, the putative receptors involved in the signalization of Der p to the innate immune cells are still poorly defined as well as the impact of their activation on the outcome of the allergen-induced cell response. We previously reported that the HDM activation of mouse alveolar macrophages (AM involves the TLR4/CD14 cell surface receptor complex. Here using a TLR ligand screening essay, we demonstrate that HDM protein extract engages the TLR2, in addition to the TLR4, in engineered TLR-transfected HEK cells but also in the MH-S mouse alveolar macrophage cell line model. Moreover we found that the concomitant recruitment of the MH-S cell's TLR2 and TLR4 receptors by the HDM extract activates the MyD88-dependent signaling pathway and leads to the secretion of the NF-κB regulated pro-inflammatory factors NO and TNF-α. However unlike with the canonical TLR4 ligand (i.e. the bacterial LPS mobilization of TLR4 by the HDM extract induces a reduced production of the IL-12 pro-inflammatory cytokine and fails to trigger the expression of the T-bet transcription factor. Finally we demonstrated that HDM extract down-regulates LPS induced IL-12 and T-bet expression through a TLR2 dependent mechanism. Therefore, we propose that the simultaneous engagement of the TLR2 and TLR4 receptors by the HDM extract results in a cross regulated original activation pattern of the AM which may contribute to the Th2 polarization of the allergen-induced immune response. The deciphering of these cross-regulation networks is of prime importance to open the way for original therapeutic strategies taking advantage of these receptors and their associated signaling pathways to treat allergic asthma.

  4. A CCL24-dependent Pathway Augments Eosinophilic Airway Inflammation in House Dust Mite-challenged Cd163−/− Mice

    Science.gov (United States)

    Dai, Cuilian; Yao, Xianglan; Gordon, Elizabeth M.; Barochia, Amisha; Cuento, Rosemarie A.; Kaler, Maryann; Meyer, Katharine S.; Keeran, Karen J.; Nugent, Gayle Z.; Jeffries, Kenneth R.; Qu, Xuan; Yu, Zu-Xi; Aponte, Angel; Gucek, Marjan; Dagur, Pradeep K.; McCoy, J. Philip; Levine, Stewart J.

    2015-01-01

    CD163 is a macrophage scavenger receptor with anti-inflammatory and pro-inflammatory functions. Here, we report that alveolar macrophages (AMΦs) from asthmatic subjects had reduced cell surface expression of CD163, which suggested that CD163 might modulate the pathogenesis of asthma. Consistent with this, house dust mite (HDM)-challenged Cd163−/− mice displayed increases in airway eosinophils and mucous cell metaplasia (MCM). The increased airway eosinophils and MCM in HDM-challenged Cd163−/− mice were mediated by augmented CCL24 production and could be reversed by administration of a neutralizing anti-CCL24 antibody. A proteomic analysis identified the calcium-dependent binding of CD163 to Dermatophagoides ptyeronyssinus peptidase 1 (Der p1). Der p1-challenged Cd163−/− mice had the same phenotype as HDM-challenged Cd163−/− mice with increases in airway eosinophils, MCM and CCL24 production, while Der p1 induced CCL24 secretion by bone marrow-derived macrophages (BMMΦs) from Cd163−/− mice, but not BMMΦs from WT mice. Lastly, airway eosinophils and bronchoalveolar lavage fluid CCL24 levels were increased in Der p1-challenged WT mice that received adoptively transferred AMΦ’s from Cd163−/− mice. Thus, we have identified CD163 as a macrophage receptor that binds Der p1. Furthermore, we have shown that HDM-challenged Cd163−/− mice have increased eosinophilic airway inflammation and MCM that are mediated by a CCL24-dependent mechanism. PMID:26376364

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

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    Zhiqiang Song

    Full Text Available 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.

  6. Long-term falls in antibodies to dust mite and pollen allergens in patients with asthma or hay fever.

    Science.gov (United States)

    Rawle, F C; Burr, M L; Platts-Mills, T A

    1983-09-01

    'Spontaneous' improvement in, or alteration of, allergic symptoms is a common occurrence, and the immunological basis is of interest in attempts to develop effective specific therapy. In the present study we measured levels of serum antibodies to Dermatophagoides pteronyssinus in patients diagnosed as having house-dust-allergic asthma up to 40 years previously. The results show a progressive fall in both IgG and IgE antibodies to antigen P1 and RAST binding to crude D. pteronyssinus extract. By contrast changes in total serum IgE were not marked. Within each of the groups of patients diagnosed 20, 30 and 40 years previously, 70% no longer suffered severe symptoms. However, the absence of detectable IgE antibody in serum was neither a necessary nor a sufficient condition for loss of symptoms. A group of patients who had spontaneously recovered from hay fever had significantly lower IgG and IgE antibody for the major grass pollen allergen Rye I and also lower total IgE than current hay fever sufferers. In neither hay fever nor asthma was there evidence to link spontaneous improvement in symptoms with an increase in IgG antibodies.

  7. Evaluation of the concentration of allergens from mites in fur and households dust of dogs with atopic dermatitis

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    Dévaki L. de Assunção

    Full Text Available ABSTRACT: This study evaluated the concentration of Der p 1, Der f 1 and Blo t 5 in the fur and households of 20 dogs with atopic dermatitis (AD and 20 healthy dogs. The diagnosis of AD was clinical based on Favrot’s criteria. Dust samples were collected with a domestic vacuum cleaner. For each site, 1m2 was vacuumed for 2 min. The samples were collected in separate filters, transferred into plastic containers, sealed and kept frozen until ELISA analysis. In the fur of atopic dogs the average concentration of Der p 1 was 0.25μg/g compared to 0.03μg/g in healthy dogs. In households with atopic dogs the highest concentrations of Der p 1 were found in carpets (2.18μg/g, followed by couches (1.53μg/g, beds (1.14μg/g, dogs’ bed linen (0.64μg/g and floors (0.14μg/g. The concentrations of Der p 1 on carpets, couches and beds were significantly higher than in atopic dogs’ fur (p0.05. The concentrations of Der p 1, Der f 1 and Blo t 5 were equivalent in atopic and non-atopic dog’s households. Among the allergens studied, Der p 1 was the most commonly found, predominantly in carpets and couches.

  8. Storage mite contamination of commercial dry dog food in south-eastern Australia.

    Science.gov (United States)

    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.

  9. The economic importance of acaricides in the control of phytophagous mites and an update on recent acaricide mode of action research.

    Science.gov (United States)

    Van Leeuwen, Thomas; Tirry, Luc; Yamamoto, Atsushi; Nauen, Ralf; Dermauw, Wannes

    2015-06-01

    Acaricides are one of the cornerstones of an efficient control program for phytophagous mites. An analysis of the global acaricide market reveals that spider mites such as Tetranychus urticae, Panonychus citri and Panonychus ulmi are by far the most economically important species, representing more than 80% of the market. Other relevant mite groups are false spider mites (mainly Brevipalpus), rust and gall mites and tarsonemid mites. Acaricides are most frequently used in vegetables and fruits (74% of the market), including grape vines and citrus. However, their use is increasing in major crops where spider mites are becoming more important, such as soybean, cotton and corn. As revealed by a detailed case study of the Japanese market, major shifts in acaricide use are partially driven by resistance development and the commercial availability of compounds with novel mode of action. The importance of the latter cannot be underestimated, although some compounds are successfully used for more than 30 years. A review of recent developments in mode of action research is presented, as such knowledge is important for devising resistance management programs. This includes spirocyclic keto-enols as inhibitors of acetyl-CoA carboxylase, the carbazate bifenazate as a mitochondrial complex III inhibitor, a novel class of complex II inhibitors, and the mite growth inhibitors hexythiazox, clofentezine and etoxazole that interact with chitin synthase I.

  10. Macrochelid Mite, Macrocheles muscaedomesticae (Acarina: Macrochelidae as a Biological Control Agent Against House Fly, Musca domestica (Diptera: Muscidae in Egypt

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    Safaa

    2014-01-01

    Full Text Available Numerous species of macrochelids (Acarina: Mesostigmata have shown capability to attack housefly larvae and eggs but it is presumed that only a few of them play a significant role in the control of flies in nature. Macrocheles muscaedomesticae (Scopoli is one of several mites that feeds on eggs, newly hatched and small larvae of house fly Musca domestica L. This study provide avidence that macrochelid mite is attacking not only housefly larvae and eggs but also on housefly adults. Macrocheles muscaedomesticae mite was reared in the laboratory on house fly frozen eggs and first instar of larvae at constant conditions of 28°C±1 and 90% relative humidity using sterilized artificial diet. The mean incubation period of eggs, total immatures, female longevity were 0.7, 4.0 and 25.2 days, respectively when fed on frozen eggs meanwhile means were 0.8, 7.0 and 22.6 days when fed on first instar larvae of M. domestica. The total consumption of female was 131.1 eggs/female or 82.7 larvae. Results of the present study showed that the mean mortality percentages of eggs due to predation of three levels of predator 2, 5 and 10 individuals were 57.2, 74.9 and 96.5 after 5, 4, 2 days, respectively. Also, the larval stage of M. domestica was introduced with three levels of 10, 20 and 25 individuals for each level of predatory mite 2, 5 and 10 adults, respectively. Results revealed that the best results were recorded at the level of 5 mites, where the mean mortality percentage of larvae was 100% after one day when introduced with 10 housefly’s larvae but it was 96% after two days when introduced with 20 housefly’s larvae and 76.2% after three days when introduced with 25 houseflies larvae at level of 5. In addition, the present study provide evidence that mites can consume the housefly adult stage. Our findings indicated that the best results were recorded at the level of 10 mites where the mean mortality percentages of adults were 83.55%, the fly died after

  11. Allergic Responses Induced by a Fungal Biopesticide Metarhizium anisopliae and House Dust Mite are Compared in a Mouse Model

    Science.gov (United States)

    Biopesticides can be effective in controlling their target pest. However, research regarding mammalian health impacts of these agents has focused on toxicity and pathogenicity, with limited research regarding allergenicity and asthma development. We compared the ability of funga...

  12. Powdered sugar shake to monitor and oxalic acid treatments to control varroa mites (Parasitiformes: Varroidae) in honey bee (Hymenoptera: Apidae) colonies

    Science.gov (United States)

    Effective monitoring and alternative strategies to control the ectoparasitic mite, Varroa destructor Anderson and Truemann (Parasitiformes: Varroidae), (varroa) are crucial for determining when to apply effective treatments to honey bee, Apis mellifera L. (Hymenoptera: Apidae), colonies. Using simpl...

  13. Residues of stirofos (rabon) in eggs of laying hens treated for northern fowl mite control by dipping.

    Science.gov (United States)

    Ivey, M C; Devaney, J A; Ivie, G W; Beerwinkle, K R

    1982-03-01

    Laying hens were treated with a wettable powder formulation of stirofos [Rabon, 2-chloro-1-(2,4,5-trichlorophenyl) vinyl dimethylphosphate] by dipping in a .5 or 1.0% actual ingredient (AI) water suspension of a 50% wettable powder (WP) stirfos formulation. Stirofos residues were detected in eggs within 1 day after treatment and reached maximum levels 3 days after dipping (.021 and .035 ppm in the low- and high-dose birds, respectively). After that time, levels of residues in eggs declined rapidly and no sample contained detectable quantities (less than .004 ppm) of stirofos after 21 days. Dipping may be a practical control method for the northern fowl mite on chickens, because stirofos dips effectively control this mite on laying hens for at least 6 weeks and because resulting residues in eggs are well below established tolerances.

  14. Lessons from interactions within the cassava green mite fungal pathogen Neozygites tanajoae system and prospects for microbial control using Entomophthorales.

    Science.gov (United States)

    Hountondji, Fabien C C

    2008-12-01

    Most fungal pathogens lack the capacity to search for their host but rather develop sit-and-wait strategies that favour contact with them. The success of these strategies depends upon the interactions of the pathogen with its host, the host plant and the environmental conditions, which altogether determine its transmissibility. Given the limited success that has characterized application of sustainable microbial control, particularly using Entomophthorales, interaction studies have been conducted with the entomophthoralean fungus Neozygites tanajoae, pathogenic to the cassava green mite (CGM), Mononychellus tanajoa, to help understand differences observed between laboratory and field performances of this pathogen. Reciprocal pathogen-host interactions as well as tritrophic interactions involving the host plant were studied. It was found that herbivory triggers the release of volatiles that promote sporulation of isolates of N. tanajoae, whereas the host mite avoids haloes of spores of this pathogen. However, the host mite does not avoid the pathogen when inside the mummified fungus-killed cadaver. The status of microbial control of CGM in Africa is reviewed and implications of these interactions are discussed for prospective application of microbial control using Entomophthorales.

  15. House dust mite major allergens Der p 1 and Der p 5 activate human airway-derived epithelial cells by protease-dependent and protease-independent mechanisms

    Directory of Open Access Journals (Sweden)

    Timmerman J André B

    2006-03-01

    Full Text Available Abstract House dust mite allergens (HDM cause bronchoconstriction in asthma patients and induce an inflammatory response in the lungs due to the release of cytokines, chemokines and additional mediators. The mechanism how HDM components achieve this is largely unknown. The objective of this study was to assess whether HDM components of Dermatophagoides pteronissinus with protease activity (Der p 1 and unknown enzymatic activity (Der p 2, Der p 5 induce biological responses in a human airway-derived epithelial cell line (A549, and if so, to elucidate the underlying mechanism(s of action. A549 cells were incubated with HDM extract, Der p 1, recombinant Der p 2 and recombinant Der p 5. Cell desquamation was assessed by microscopy. The proinflammatory cytokines, IL-6 and IL-8, were measured by ELISA. Intracellular Ca2+ levels were assessed in A549 cells and in mouse fibroblasts expressing the human protease activated receptor (PAR1, PAR2 or PAR4. HDM extract, Der p 1 and Der p 5 dose-dependently increased the production of IL-6 and IL-8. Added simultaneously, Der p 1 and Der p 5 further increased the production of IL-6 and IL-8. The action of Der p 1 was blocked by cysteine-protease inhibitors, while that of Der p 5 couldn't be blocked by either serine- or cysteine protease inhibitors. Der p 5 only induced cell shrinking, whereas HDM extract and Der p1 also induced cell desquamation. Der p 2 had no effect on A549 cells. Der p 1's protease activity causes desquamation and induced the release of IL6 and IL-8 by a mechanism independent of Ca2+ mobilisation and PAR activation. Der p 5 exerts a protease-independent activation of A549 that involves Ca2+ mobilisation and also leads to the production of these cytokines. Together, our data indicate that allergens present in HDM extracts can trigger protease-dependent and protease-independent signalling pathways in A549 cells.

  16. Block copolymer/DNA vaccination induces a strong allergen-specific local response in a mouse model of house dust mite asthma.

    Directory of Open Access Journals (Sweden)

    Camille Rolland-Debord

    Full Text Available BACKGROUND: Allergic asthma is caused by abnormal immunoreactivity against allergens such as house dust mites among which Dermatophagoides farinae (Der f is a common species. Currently, immunotherapy is based on allergen administration, which has variable effect from patient to patient and may cause serious side effects, principally the sustained risk of anaphylaxis. DNA vaccination is a promising approach by triggering a specific immune response with reduced allergenicity. OBJECTIVE: The aim of the study is to evaluate the effects of DNA immunization with Der f1 allergen specific DNA on allergic sensitization, inflammation and respiratory function in mice. METHODS: Mice were vaccinated 28 and 7 days before allergen exposure with a Der f1-encoding plasmid formulated with a block copolymer. Asthma was induced by skin sensitization followed by intra-nasal challenges with Der f extract. Total lung, broncho-alveolar lavage (BAL and spleen cells were analyzed by flow cytometry for their surface antigen and cytokine expression. Splenocytes and lung cell IFN-γ production by CD8+ cells in response to Der f CMH1-restricted peptides was assessed by ELISPOT. IgE, IgG1 and IgG2a were measured in serum by ELISA. Specific bronchial hyperresponsiveness was assessed by direct resistance measurements. RESULTS: Compared to animals vaccinated with an irrelevant plasmid, pVAX-Der f1 vaccination induced an increase of B cells in BAL, and an elevation of IL-10 and IFN-γ but also of IL-4, IL-13 and IL-17 producing CD4+ lymphocytes in lungs and of IL-4 and IL-5 in spleen. In response to CD8-restricted peptides an increase of IFN-γ was observed among lung cells. IgG2a levels non-specifically increased following block copolymer/DNA vaccination although IgE, IgG1 levels and airways resistances were not impacted. CONCLUSIONS & CLINICAL RELEVANCE: DNA vaccination using a plasmid coding for Der f1 formulated with the block copolymer 704 induces a specific immune response

  17. Activation of the Prostaglandin E2 receptor EP2 prevents house dust mite-induced airway hyperresponsiveness and inflammation by restraining mast cells' activity.

    Science.gov (United States)

    Serra-Pages, M; Torres, R; Plaza, J; Herrerias, A; Costa-Farré, C; Marco, A; Jiménez, M; Maurer, M; Picado, C; de Mora, F

    2015-10-01

    Prostaglandin E2 (PGE2 ) has been proposed to exert antiasthmatic effects in patients, to prevent antigen-induced airway pathology in murine models, and to inhibit mast cells (MC) activity in vitro. To assess in a murine model whether the protective effect of PGE2 may be a consequence of its ability to activate the E-prostanoid (EP)2 receptor on airway MC. Either BALB/c or C57BL/6 mice were exposed intranasally (i.n.) to house dust mite (HDM) aeroallergens. Both strains were given PGE2 locally (0.3 mg/kg), but only BALB/c mice were administered butaprost (EP2 agonist: 0.3 mg/kg), or AH6809 (EP2 antagonist; 2.5 mg/kg) combined with the MC stabilizer sodium cromoglycate (SCG: 25 mg/kg). Airway hyperresponsiveness (AHR) and inflammation, along with lung MC activity, were evaluated. In addition, butaprost's effect was assessed in MC-mediated passive cutaneous anaphylaxis (PCA) in mice challenged with 2,4-dinitrophenol (DNP). Selective EP2 agonism attenuated aeroallergen-caused AHR and inflammation in HDM-exposed BALB/c mice, and this correlated with a reduced lung MC activity. Accordingly, the blockade of endogenous PGE2 by means of AH6809 worsened airway responsiveness in sensitive BALB/c mice, and such worsening was reversed by SCG. The relevance of MC to PGE2 -EP2 driven protection was further highlighted in MC-dependent PCA, where butaprost fully prevented MC-induced ear swelling. Unlike in BALB/c mice, PGE2 did not protect the airways of HDM-sensitized C57BL/6 animals, a strain in which we showed MC to be irrelevant to aeroallergen-driven AHR and inflammation. The beneficial effect of both exogenous and endogenous PGE2 in aeroallergen-sensitized mice may be attributable to the activation of the EP2 receptor, which in turn acts as a restrainer of airway MC activity. This opens a path towards the identification of therapeutic targets against asthma along the 'EP2 -MC-airway' axis. © 2015 John Wiley & Sons Ltd.

  18. Field study on the efficacy of an extract of neem seed (Mite -Stop) against the red mite Dermanyssus gallinae naturally infecting poultry in Egypt.

    Science.gov (United States)

    Abdel-Ghaffar, Fathy; Sobhy, Hassan M; Al-Quraishy, Saleh; Semmler, Margit

    2008-08-01

    Infestations with the poultry red mite Dermanyssus gallinae represent a major ectoparasite problem in poultry and affects egg and meat production worldwide. The effects of the neem seed product Mite-Stop against the red poultry mite were investigated. Five primitive poultry farms in two small villages in the Nile Delta and Giza district were selected for the study. The neem extract was diluted 1:40 and 1:50 with tap water just prior to use. Application of the two dilutions of the provided product was performed to soil, cracks and crevices of the examined area as well as to mite-infested birds on day 0 and day 7. Two hours after treatment soil dust was collected from sprayed regions of the stable and from unsprayed control regions of the same stable. The treated chickens were also checked for mites 2 h after each treatment. The examination of the chickens 2 h after spraying showed that they were free of mites. The examination of treated soil with the Tullgren funnel apparatus 2 h after the first spraying on day 0 already showed a considerable reduction of living mites compared to controls. Seven days after the first treatment of the soil the number of living mites was reduced for 80% in the treated soil and decreased even more after the second spraying, since those larvae that had hatched from eggs in the meantime were killed. The 1:40 dilution of the neem seed extract with tap water was superior to the 1:50 dilution. These results clearly show a very high killing rate of the extract, if the mites come in direct contact with the compound. However, in order to obtain extinction also of hidden and freshly hatched stages repeated spraying should be done three times within 8-10 days.

  19. Airway wall thickness of allergic asthma caused by weed pollen or house dust mite assessed by computed tomography.

    Science.gov (United States)

    Liu, Liping; Li, Guangrun; Sun, Yuemei; Li, Jian; Tang, Ningbo; Dong, Liang

    2015-03-01

    Little was known about Airway wall thickness of asthma patients with different allergen allergy. So we explored the possible difference of Airway wall thickness of asthma patients mono-sensitized to weed pollen or HDM using high-resolution computed tomography. 85 severe asthma patients were divided into weed pollen group and HDM group according to relevant allergen. 20 healthy donors served as controls. Airway wall area, percentage wall area and luminal area at the trunk of the apical bronchus of the right upper lobe were quantified using HRCT and compared. The values of pulmonary function were assessed as well. There were differences between HDM group and weed pollen group in WA/BSA,WA% and FEF25-75% pred, and no significant difference in FEV1%pred, FEV1/FVC and LA/BSA. In weed pollen group, WA/BSA was observed to correlate with the duration of rhinitis, whereas in HDM group, WA/BSA and LA/BSA was observed to correlate with the duration of asthma. In weed pollen group, FEV1/FVC showed a weak but significant negative correlation with WA%, but in HDM group FEV1/FVC showed a significant positive correlation with WA% and a statistical negative correlation with LA/BSA. FEV1/FVC and FEF25-75% pred were higher and WA/BSA and LA/BSA were lower in healthy control group than asthma group. FEV1%pred and WA% was no significant difference between asthma patients and healthy subjects. There are differences between HDM mono-sensitized subjects and weed pollen mono-sensitized subjects, not only in airway wall thickness, but also small airway obstruction. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Research by NIOSH for controlling respirable dust and methane gas on continuous miner faces

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, G.V.R.; Taylor, C.D.; Colinet, J.F.; Thimons, E.D. [National Institute for Occupational Safety and Health, Pittsburgh, PA (USA). Pittsburgh Research Laboratory, Dust and Toxic Substances Control Branch

    2001-07-01

    The importance of controlling respirable dust and methane gas levels in underground coal mining cannot be underestimated. While respirable dust can significantly affect the occupational health of underground coal miners, methane gas accumulations pose significant safety concerns for these same workers. Water sprays and machine mounted dust scrubbers offer effective control of respirable dust exposures and methane gas accumulations. Water must not only be applied carefully to avoid dust rollback to the machine operator but must create sufficient turbulence to remove dead zones that could contain high concentrations of methane gas. While the flooded-bed dust scrubber has been generally responsible for decreased worker exposures to respirable dusts, this device has proved effective in controlling methane levels at the face. This paper reviews practical applications of water sprays and dust scrubbers to control respirable dust and methane gas on continuous miner faces. 15 refs., 6 figs.

  1. Prominent IgE-binding and cytokine-inducing capacities of a newly cloned N-terminal region of Der f 14, an apolipophorin-like house dust mite allergen.

    Science.gov (United States)

    ElRamlawy, Kareem Gamal; Fujimura, Takashi; Aki, Tsunehiro; Okada, Akiyasu; Suzuki, Takayuki; Abe, Takuya; Hayashi, Takaharu; Epton, Michael J; Thomas, Wayne R; Rafeet, Inas Hussein; Al-Azhary, Diaa Beshr; Ono, Kazuhisa; Kawamoto, Seiji

    2017-09-11

    We previously characterized a 177 kDa allergen, M-177, from Dermatophagoides farinae. Thereafter, a counterpart to M-177 for Euroglyphus maynei was cloned as Eur m 14, and its sequence revealed that two environmental allergens, Mag 1 and Mag 3, are digested fragments of M-177. The aims of this study were to clone the cDNA of Der f 14 corresponding to M-177 and to elucidate the allergenic capacities of the N-terminal fragment of Der f 14 (Der f 14-N). Recombinant allergens were produced as trigger-factor-fused proteins in Escherichia coli. Der f 14-N showed the highest IgE-binding frequency among Der f 14-derived fragments in patients allergic to house dust mite by enzyme-linked immunosorbent assay. Der f 14-N showed the highest capacity to induce cell proliferation in murine lymphocyte and human peripheral mononuclear cells among Der f 14-derived fragments. Der f 14-N induced IL-13, IFN-γ, and IL-17 production more than Der f 1 and Der f 2 in mouse, and induced IL-5 and IFN-γ production at levels comparable to those of Der f 1 and Der f 2 in some patients. The high prevalence of IgE binding to the Der f 14-N indicates that it could be an important mite allergen. © The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  2. Enzymatic activity in extracts of allergy-causing astigmatid mites.

    Science.gov (United States)

    Morgan, Marjorie S; Arlian, Larry G

    2006-11-01

    Many of the previously characterized allergens of house dust mites are known to be proteases, and this enzymatic activity is thought to contribute to their allergenicity. Other astigmatid mites, including stored-product mites and the ectoparasitic itch mite, Sarcoptes scabiei De Geer, are also known to be allergenic, but little or nothing is known about their enzymatic activities. The purpose of this study was to characterize the enzymatic activities present in extracts of the parasitic itch mite and from eight other species of free-living astigmatid mites. Extracts were prepared from one parasitic mite (S. scabiei), five stored-product mites (Chortoglyphus arcuatus (Troupeau), Lepidoglyphus destructor (Schrank), Blomia tropicalis Bronswijk, Cock, Oshima, Tyrophagus putrescentiae (Schrank), and Acarus siro L.), and three house dust mites [Dermatophagoidesfarinae Hughes, Dermatophagoides pteronyssinus (Troussart), and Euroglyphus maynei (Cooreman) ]. ApiZym strips were used to screen for the presence of 19 individual enzyme activities. Digestion of nine other substrates was evaluated by spectrophotometric or electrophoretic methods. All mite extracts exhibited some form of phosphatase, esterase, aminopeptidase, and glycosidase activity, although their substrate specificities varied considerably. Itch mite extract did not possess detectable serine peptidase activity nor was it able to hydrolyze gelatin or casein, whereas all other mite extracts exhibited these activities. Storage mite extracts possessed enzymes capable of degrading the widest range of substrates, whereas itch mite extract had the most limited proteolytic capacity. Extracts of nine species of allergy-causing astigmatid mites contain wide and diverse repertoires of enzymatic activities. These catalytic activities may be important contributors to the induction and manifestation of inflammatory and immune responses to mites in patients.

  3. Single versus multiple enemies and the impact on biological control of spider mites in cassava fields in West-Africa.

    Science.gov (United States)

    Onzo, Alexis; Sabelis, Maurice W; Hanna, Rachid

    2014-03-01

    To determine whether to use single or multiple predator species for biological pest control requires manipulative field experiments. We performed such tests in Benin (West Africa) in cassava fields infested by the cassava green mite Mononychellus tanajoa, and the cotton red mite Oligonychus gossypii. These fields also harboured the cassava apex-inhabiting predator Typhlodromalus aripo and either the leaf-inhabiting predator Amblydromalus manihoti or Euseius fustis. We manipulated predator species composition on individual plants to determine their effect on prey and predator densities. In fields with T. aripo plus A. manihoti, M. tanajoa densities were reduced by T. aripo alone or together with A. manihoti, but neither of these predators, alone or together, reduced O. gossypii densities. In fields with T. aripo plus E. fustis, T. aripo alone or together with E. fustis exerted significant control over O. gossypii, but weak control over M. tanajoa. Densities of any of the predator species were not affected by co-occurring predator species, suggesting a minor role for intraguild predation in the field, contrary to earlier experiments on small plants in the laboratory. We conclude that (1) T. aripo is the most effective predator species in suppressing M. tanajoa, (2) two predator species, T. aripo and E. fustis, are needed to suppress O. gossypii, and (3) predator species together on the same plant do not negatively affect each other nor the extent to which they control their prey. We argue that intraguild predation is reduced due to partial niche separation among predator species.

  4. Prenatal exposure to mite and pet allergens and total serum IgE at birth in high-risk children.

    NARCIS (Netherlands)

    Schonberger, H.J.; Dompeling, E.C.; Knottnerus, J.A.; Kuiper, S.; Weel, C. van; Schayck, C.P. van

    2005-01-01

    To examine the relationship between prenatal exposure to mite, cat and dog allergens and total serum IgE at birth in newborns at high risk of asthma. In the homes of 221 newborns with at least one first-degree relative with asthma, concentrations (ng/g dust) of allergens of house dust mite (mite), c

  5. Interactions between two neotropical phytoseiid predators on cassava plants and consequences for biological control of a shared spider mite prey: a screenhouse evaluation

    NARCIS (Netherlands)

    Onzo, A.; Hanna, R.; Janssen, A.; Sabelis, M.W.

    2004-01-01

    The issue of introducing single or multiple natural enemy species for classical biological control has been an area of intense inquiry by ecologists and biological control practitioners. This is particularly relevant to classical biological control of cassava green mite Mononychellus tanajoa

  6. Advances of nanoparticle-DNA vaccine of house dust mite%纳米粒子-DNA疫苗治疗屋尘螨抗原过敏的研究进展

    Institute of Scientific and Technical Information of China (English)

    崔运勇; 杨慧

    2011-01-01

    Der p 1 and Der p 2 are the most characteristic allergic antigen during the research of house dust mite desensitization therapy, Der p 2 is substituting the former because of its stability and resistance to degradation. The traditional specific immunotherapy is limited because of long cure cycle,side effect and the lack of patients' compliance. Though oral DNA vaccine don't have these drawbacks, it's difficult to overcome the substance during GI tract. Nanoparticles-DNA vaccine is widely used in recent years,the main advantage of nanoparticles embed with DNA vaccines is it can effectively protect the DNA vaccine. This article is a review of the research of using nanoparticles in curing house dust mite allergy.%在屋尘螨多种变应原中,Der p1和Der p2是研制屋尘螨变应原疫苗主要的特异性抗原,而Der p2由于较Der p1更稳定和耐降解正逐渐取代后者.传统的过敏原特异性治疗的周期长、易产生不良反应、患者依从性差,口服DNA疫苗可以消除上述困难,但又难以克服消化道中的各种屏障,利用纳米粒子包被DNA疫苗可以有效保护DNA疫苗不被降解,因此得到了广泛认可.本文就纳米粒子-DNA疫苗治疗屋尘螨抗原过敏的研究进展作一综述.

  7. The effect of disodium cromoglycate, budesonide, and cyclosporin A on interleukin-4, interleukin-5, and interleukin-13 secretions in Der p I-stimulated T cells from house dust mite-sensitive atopic and nonatopic individuals.

    Science.gov (United States)

    Oh, Jae-Won; Lee, Ha-Baik; Chung, Yong-Hoon; Choi, Yong

    2002-01-01

    Disodium cromoglycate (DSCG), budesonide, and cyclosporin A (CsA) were the well-known immunomodulators for the allergic and immunologic diseases clinically. In this study, we evaluated the characteristics of inhibition on cytokine synthesis of Der p I-stimulated T cells by the same inhibiting concentrations of DSCG, budesonide, and CsA in house-dust mite antigen (Der p I)-specific atopic and nonatopic healthy individuals. Seven house dust mite allergen specific patients were recruited for this study. Seven healthy volunteers were included on the basis of negative allergic manifestations and low serum immunoglobulin E values. Peripheral blood mononuclear cells (PBMCs) were cultured in the presence of recombinant interleukin (rIL)-2 with or without budesonide, DSCG, CsA, and Der p I for 48 hours. Cells were stained with anti-CD4 fluorescein isothiocyanate-conjugated monoclonal antibody, and then anti-human IL-4 phycoerythrin, IL-5, or IL-13 monoclonal antibody, respectively, was added to both blocked and stained samples. Incubation of PBMC from atopics with each immunomodulator and Der p I resulted in the reduction of IL-4 secretion compared with Der p I alone stimulation. However, IL-4 secretion in PBMC from nonatopics was not reduced with DSCG and Der p I stimulation. IL-4, IL-5, and IL-13 secretions of PBMC from atopics were significantly decreased after incubation with each immunomodulator and Der p I, compared with after incubation with Der p I alone. These results might be considered to show either that DSCG has a selective inhibiting effect on cytokine production in T cells from atopics or is a weak inhibitor of cytokine secretions compared with budesonide and CsA at even strength for the inhibition of lymphocyte proliferation in normal, healthy individuals.

  8. Development of a cDNA microarray for the measurement of gene expression in the sheep scab mite Psoroptes ovis

    Directory of Open Access Journals (Sweden)

    Burgess Stewart TG

    2012-02-01

    Full Text Available Abstract Background Sheep scab is caused by the ectoparasitic mite Psoroptes ovis which initiates a profound cutaneous inflammatory response, leading to the development of the skin lesions which are characteristic of the disease. Existing control strategies rely upon injectable endectocides and acaricidal dips but concerns over residues, eco-toxicity and the development of acaricide resistance limit the sustainability of this approach. In order to identify alternative means of disease control, a deeper understanding of both the parasite and its interaction with the host are required. Methods Herein we describe the development and utilisation of an annotated P. ovis cDNA microarray containing 3,456 elements for the measurement of gene expression in this economically important ectoparasite. The array consists of 981 P. ovis EST sequences printed in triplicate along with 513 control elements. Array performance was validated through the analysis of gene expression differences between fed and starved P. ovis mites. Results Sequences represented on the array include homologues of major house dust mite allergens and tick salivary proteins, along with factors potentially involved in mite reproduction and xenobiotic metabolism. In order to validate the performance of this unique resource under biological conditions we used the array to analyse gene expression differences between fed and starved P. ovis mites. These analyses identified a number of house dust mite allergen homologues up-regulated in fed mites and P. ovis transcripts involved in stress responses, autophagy and chemosensory perception up-regulated in starved mites. Conclusion The P. ovis cDNA microarray described here has been shown to be both robust and reproducible and will enable future studies to analyse gene expression in this important ectoparasite.

  9. Ingestion of milk containing the Dp2 peptide, a dust mite allergen, protects mice from allergic airway inflammation and hyper-responsiveness

    OpenAIRE

    Liu, Hsu-Chung; Pai, Shun-Yuan; Cheng, Winston TK; Chen, Hsiao-Ling; Tsai, Tung-Chou; Yang, Shang-Hsun; Chen, Chuan-Mu

    2013-01-01

    Background Allergen-specific immunotherapy has been demonstrated to have potential for the treatment of allergic diseases. Transgenic animals are currently the best available bioreactors to produce recombinant proteins, which can be secreted in milk. It has not been clearly demonstrated whether milk from transgenic animals expressing recombinant allergens has immunomodulatory effects on allergic asthma. Methods We aimed to determine whether the oral administration of milk containing a mite al...

  10. Selection of Beauveria bassiana (Bals. Vuill. and Metarhizium anisopliae (Metsch. Sorok. for the control of the mite Mononychellus tanajoa (Bondar

    Directory of Open Access Journals (Sweden)

    Barreto Rodrigo Soares

    2004-01-01

    Full Text Available The green mite, Mononychellus tanajoa (Bondar (Acari: Tetranychidae, is considered to be one of the key pests in cassava, Manihot esculenta Crants, leading to considerable field losses. In this study, ten Beauveria bassiana (Bals. Vuill. and ten Metarhizium anisopliae (Metsch. Sorok. isolates were evaluated with regard to their potential as biological control agents against adult M. tanajoa females. The total mortality percentage of M. tanajoa caused by B. bassiana ranged from 13.0 to 97.0%, with confirmed mortality rates extending from 9.0 to 91.0% and LT50 varying from 4.2 to 17.0 days. The M. anisopliae isolates showed total mortality percentages ranging from 12.0 to 45.0% with confirmed mortality rates extending from 8.0 to 45.0%, and LT50 varying from 8.6 to 19.8 days. Lethal Concentrations (LC50 of 3.93 × 10(6 conidia mL-1 and 7.44 × 10(8 conidia mL-1 were determined for B. bassiana and M. anisopliae, respectively. B. bassiana isolate 645 was the most efficient, being an alternative for use in biological control programs against the cassava green mite.

  11. Wetting agent investigation for controlling dust of lead-zinc ores

    Institute of Scientific and Technical Information of China (English)

    WU Chao; PENG Xiao-lan; WU Guo-min

    2007-01-01

    The purpose of this project is to control the pollution of dust, which occurred in a typical lead-zinc mine. Two kinds of surfactants and water glass were chosen as the wetting agents to study the behaviours of suppressing the dust. The performances of the wetting agents of various sizes and water content of dust and their compositions among different weting agents were investigated. Firstly, the chemical compounds, dispersity, water content, bulk density and other relevant physico-chemical properties of the choiced dust of lead-zinc ore were mensurated. A great number of down-ward penetrating tests were conducted to different partical sizes of dust and to analyze the dust wetting behaviour respectively. The optimal compositions of wetting agents were obtained in accordance with different water contents and partical sizes of the dust after analyzing and statisting the achieved experimental data. The data show that the efficiency of chemical dust suppression of weting agents is much better than that of water. The results of the research work prove that the partical size and the water content of the dust are very important factors to the dust suppression. The results are also proved validly by the dropping experiment, which takes the penetrating diameter and penetrating time as the major factors. The superfine dust is much more difficult to be wetted. Since increasing the water content of dust is the best approach to control it, the choice of wetting agents for improving dispensation is significant.

  12. Ear Mite Removal in the Santa Catalina Island Fox (Urocyon littoralis catalinae: Controlling Risk Factors for Cancer Development.

    Directory of Open Access Journals (Sweden)

    Megan E Moriarty

    Full Text Available Ear mites (Otodectes cynotis and ear canal tumors are highly prevalent among federally endangered Island foxes (Urocyon littoralis catalinae living on Santa Catalina Island off the coast of Southern California. Since studies began in the 1990s, nearly all foxes examined were found to be infected with ear mites, and ceruminous gland tumors (carcinomas and adenomas were detected in approximately half of all foxes ≥ 4 years of age. We hypothesized that reduction of ear mite infection would reduce otitis externa and ceruminous gland hyperplasia, a risk factor for tumor development. In this study, we conducted a randomized field trial to assess the impact of acaricide treatment on ear mite prevalence and intensity of infection, otitis externa, ceruminous gland hyperplasia, and mite-specific IgG and IgE antibody levels. Treatment was highly effective at eliminating mites and reducing otitis externa and ceruminous gland hyperplasia, and mite-specific IgG antibody levels were significantly lower among uninfected foxes. Ceruminous gland hyperplasia increased in the chronically infected, untreated foxes during the six month study. Our results provide compelling evidence that acaricide treatment is an effective means of reducing ear mites, and that mite removal in turn reduces ear lesions and mite-specific IgG antibody levels in Santa Catalina Island foxes. This study has advanced our understanding of the underlying pathogenesis which results in ceruminous gland tumors, and has helped inform management decisions that impact species conservation.

  13. Dust control equipment of UO type used in the suction or combined ventilation systems

    Energy Technology Data Exchange (ETDEWEB)

    Frydel, W.; Steindor, M. [KOMAG, Gliwice (Poland). Mining Mechanization Centre

    2001-07-01

    Systems for dust control and ventilation of roadways, using suction or forced (combined) ventilation, are a combination of dust control installations of the UO type and the equipment for the ventilation of roadways. The electrical equipment, essential for supplying and controlling the installation as well as methane detectors, are incorporated. The system ensures safe and efficient dust control and ventilation of roadways and guarantees proper inter co-ordination of units, which form part of it. Satisfactory solutions for the system have been possible by the installation of efficient and safe dust control equipment and the use of special vortex ventubes, removing methane accumulated under the roof and operating under conditions of high dust concentration and methane explosion risk. The solutions described are used in all in Polish workings mine. Since their installation no dust or methane explosions have occurred. At the same time the incidence of pneumoconiosis cases has been reduced. 2 figs.

  14. Influence of Air Humidity and Water Particles on Dust Control Using Ultrasonic Atomization

    Science.gov (United States)

    Okawa, Hirokazu; Nishi, Kentaro; Shindo, Dai; Kawamura, Youhei

    2012-07-01

    The influence of air humidity and water particles on dust control was examined using ultrasonic atomization at 2.4 MHz, an acrylic box (61 L), and four types of ore dust samples: green tuff (4 µm), green tuff (6 µm), kaolin, and silica. It was clearly demonstrated that ultrasonic atomization was effective in raising humidity rapidly. However, at high relative air humidity, the water particles remained stable in the box without changing to water vapor. Ultrasonic atomization was applied to suppress dust dispersion and 40-95% dust reduction was achieved at 83% relative air humidity. Dust dispersion was more effective with ultrasonic atomization than without.

  15. Scaling up tests on virulence of the cassava green mite fungal pathogen Neozygites tanajoae (Entomophthorales: Neozygitaceae) under controlled conditions: first observations at the population level.

    Science.gov (United States)

    Hountondji, Fabien Charles Cossi; Hanna, Rachid; Cherry, Andy J; Sabelis, Maurice W; Agboton, Bonaventure; Korie, Sam

    2007-01-01

    Virulence of entomopathogens is often measured at the individual level using a single host individual or a group of host individuals. To what extent these virulence assessments reflect the impact of an entomopathogen on their host in the field remains largely untested, however. A methodology was developed to induce epizootics of the cassava green mite fungal pathogen Neozygites tanajoae under controlled conditions to evaluate population-level virulence of two (one Beninese and one Brazilian) isolates of the entomopathogen--which had shown similar individual-level virulence but different field impacts. In unrepeated separate experiments we inoculated mite-infested potted cassava plants with either 50 or 25 live mites (high and low inoculum) previously exposed to spores of N. tanajoae and monitored the development of fungal infections for each isolate under the same conditions. Both isolates caused mite infections and an associated decline in host mite populations relative to the control (without fungus) in all experiments, but prevalence of the fungus varied with isolate and increased with inoculum density. Peak infection levels were 90% for the Beninese isolate and 36% for the Brazilian isolate at high inoculum density, and respectively 17% and 25% at low inoculum density. We also measured dispersal from inoculated plants and found that spore dispersal increased with host infection levels, independent of host densities, whereas mite dispersal varied between isolates. These results demonstrate that epizootiology of N. tanajoae can be studied under controlled conditions and suggest that virulence tests at the population level may help to better predict performance of fungal isolates than individual-level tests.

  16. Allergy to mites : relation to lung function and airway hyperresponsiveness

    NARCIS (Netherlands)

    van der Heide, S; Dubois, AEJ; Kauffman, HF; de Monchy, JGR

    1998-01-01

    Exposure to house-dust-mite allergens is an important cause of allergic reactions in sensitized patients. In community-based studies, sensitization to house-duct mites, as ascertained by a positive skin test or by an increased allergen-specific IgE level in serum, is associated with both diminished

  17. Mattress encasings and mite allergen levels in the Prevention and Incidence of Asthma and Mite Allergy study

    NARCIS (Netherlands)

    van Strien, RT; Koopman, LP; Kerkhof, M; Oldenwening, M; de Jongste, JC; Gerritsen, J; Neijens, HJ; Aalberse, RC; Smit, HA; Brunekreef, B

    2003-01-01

    Background Reduction of allergen exposure from birth may reduce sensitization and subsequent allergic disease. Objective To measure the influence of mite allergen-impermeable mattress encasings and cotton placebo encasings on the amount of dust and mite allergen in beds. Methods A total of 810 child

  18. Mattress encasings and mite allergen levels in the Prevention and Incidence of Asthma and Mite Allergy study

    NARCIS (Netherlands)

    van Strien, RT; Koopman, LP; Kerkhof, M; Oldenwening, M; de Jongste, JC; Gerritsen, J; Neijens, HJ; Aalberse, RC; Smit, HA; Brunekreef, B

    2003-01-01

    Background Reduction of allergen exposure from birth may reduce sensitization and subsequent allergic disease. Objective To measure the influence of mite allergen-impermeable mattress encasings and cotton placebo encasings on the amount of dust and mite allergen in beds. Methods A total of 810 child

  19. Climate controls on dust storm occurrence in Maowusu Desert, Inner Mongolia, North China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Dust storms occurring in arid and semi-arid regions play a main role in the evolution of landscapes. Climate is generally regarded to be important factors influencing the occurrence of dust storm, however, the way of climate controlling dust storms had been poorly understood. In this paper, we present the Ew Index model to describe the relationship between climate variables and dust storm frequency using the available meteorological data from three meteorological stations in Maowusu Desert. This index model explains 96.8%, 69.8% and 65.3% of the variance of dust storm frequency in three regions from the north to the south,respectively and this difference is probably caused by the difference of the human disturbance. The Ew Index model is an effective predictor of dust storm frequency and provides us a quite good understanding on the occurrence of dust storms in Maowusu Desert.

  20. Brood removal or queen caging combined with oxalic acid treatment to control varroa mites (Varroa destructor) in honey bee colonies (Apis mellifera)

    Science.gov (United States)

    Few studies of honey bee colonies exist where varroa mite control is achieved by integrating broodless conditions, through either total brood removal or queen caging, in combination with oxalic acid (OA) applications. We observed significant varroa mortality after applications of OA in obtaining bro...

  1. Advances in dust control technology on South African underground coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Belle, B.K.; Du Plessis, J. [CSIR: Miningtek, Pretoria (South Africa)

    2001-07-01

    Despite the much-heralded arrival of the new millennium, improving mine health and safety remains an enormous challenge. Considerable progress with environmental (dust and methane) control in South African mines has indeed been made but it remains a matter of great concern to all parties, i.e. mine management, labor and the government. The introduction of the 1997 Directive on dust exposure and mine ventilation was a milestone for the South African coal mining industry in improving health and safety standards. These stricter guidelines and the latest dust control technologies are beneficial not only in the long-term health perspective, but also to in terms of controlling methane and coal dust explosions (high-risk) in the short term. Over the past two years, CSIR: Miningtek personnel developed new dust control systems through various Safety In Mines Research Advisory Committee (SIMRAC) funded projects and successfully implemented them in underground coal mines. Currently, it can be confidently claimed that the new and proven dust control systems are being effectively operated in more than 80% of the bord and pillar sections in South Africa. This paper highlights the critical components of the new dust control systems evaluated underground, viz., the half-curtain system, the retrofitted hood system, the double scrubber system and the integrated hood system for continuous miners, and the road header dust control system. The status of wet head dust control systems and the challenges facing high seam longwall mines are also presented in the paper. The relative effectiveness of various dust control systems are discussed and the relevant test results are given in the paper. It concludes with a discussion of the progress made and challenges facing the coal mining industry in reducing workers' exposure to respirable dust. 11 refs., 5 figs.

  2. The Potential of Bee-Generated Carbon Dioxide for Control of Varroa Mite (Mesostigmata: Varroidae) in Indoor Overwintering Honey bee (Hymenoptera: Apidae) Colonies.

    Science.gov (United States)

    Bahreini, Rassol; Currie, Robert W

    2015-10-01

    The objective of this study was to manipulate ventilation rate to characterize interactions between stocks of honey bees (Apis mellifera L.) and ventilation setting on varroa mite (Varroa destructor Anderson and Trueman) mortality in honey bee colonies kept indoors over winter. The first experiment used colonies established from stock selected locally for wintering performance under exposure to varroa (n = 6) and unselected bees (n = 6) to assess mite and bee mortality and levels of carbon dioxide (CO2) and oxygen (O2) in the bee cluster when kept under a simulated winter condition at 5°C. The second experiment, used colonies from selected bees (n = 10) and unselected bees (n = 12) that were exposed to either standard ventilation (14.4 liter/min per hive) or restricted ventilation (0.24 liter/min per hive, in a Plexiglas ventilation chamber) during a 16-d treatment period to assess the influence of restricted air flow on winter mortality rates of varroa mites and honey bees. Experiment 2 was repeated in early, mid-, and late winter. The first experiment showed that under unrestricted ventilation with CO2 concentrations averaging level (3.82 ± 0.31%, range 0.43-8.44%) increased by 200% relative to standard ventilation (1.29 ± 0.31%; range 0.09-5.26%) within the 16-d treatment period. The overall mite mortality rates and the reduction in mean abundance of varroa mite over time was greater under restricted ventilation (37 ± 4.2%) than under standard ventilation (23 ± 4.2%) but not affected by stock of bees during the treatment period. Selected bees showed overall greater mite mortality relative to unselected bees in both experiments. Restricting ventilation increased mite mortality, but did not affect worker bee mortality relative to that for colonies under standard ventilation. Restricted ventilation did not affect the overall level of Nosema compared with the control. However, there was an interaction between stock, season, and

  3. Prokaryotic expression and purification of recombinant products of group 2 house dust mite allergen%重组粉尘螨Ⅱ类变应原的原核表达及纯化

    Institute of Scientific and Technical Information of China (English)

    常维佳; 姜玉新; 陈文魁; 周书林

    2012-01-01

    Objectives To express and purify the cDNA of the group 2 allergen of Dermatophagoides farinae (Der f 2) and to determine the allergic activity of the resulting recombinant protein. Methods The Der f 2 gene was inserted into the expression vector pET-30a( + ) and transformed into competent E. Colt BL21 (DE3). The product induced by IPTG was analyzed with SDS-PAGE. The ability of Ig E to bind with sera from patients with an allergy to house dust mites was detected. Results SDSrPAGE testing showed that the amplified product with recombinant vector pET-30a-Der f 2 had a molecular mass of 15ku. This is consistent with the expected value. ELISA testing showed that the protein bound with the serum Ig E from patients with asthma. Conclusion Der f 2 has been successfully expressed in E. Colt and the purified recombinant protein has good allergenicity, providing a basis for animal testing of ASIT to treat allergy to house dust mites.%目的 表达并纯化粉尘螨2类变应原Der f 2蛋白,检测其变应原性. 方法 用1 mmol/L的IPTG诱导含重组质粒pET30a-Der f2的大肠埃希菌BL21( DE3),SDS-PAGE电泳检测并纯化目的蛋白,ELISA检测其与尘螨哮喘患者血清IgE的结合活性. 结果 SDS-PAGE电泳检测重组质粒pET30a-Der f 2表达产物,其分子质量单化为15 ku,与预期大小相符.ELISA检测纯化的Der f 2蛋白可与尘螨哮喘患者血清IgE反应. 结论 成功获得并纯化了Der f2重组蛋白,该蛋白具有变应原性,为进行尘螨过敏性疾病的变应原特异性免疫治疗的动物实验奠定了物质基础.

  4. Airway Microbial Diversity is Inversely Associated with Mite-Sensitized Rhinitis and Asthma in Early Childhood.

    Science.gov (United States)

    Chiu, Chih-Yung; Chan, Yi-Ling; Tsai, Yu-Shuen; Chen, Ssu-An; Wang, Chia-Jung; Chen, Kuan-Fu; Chung, I-Fang

    2017-05-12

    Microbiota plays an important role in regulating immune responses associated with atopic diseases. We sought to evaluate relationships among airway microbiota, serum IgE levels, allergic sensitization and their relevance to rhinitis and asthma. Microbial characterization was performed using Illumina-based 16S rRNA gene sequencing of 87 throat swabs collected from children with asthma (n = 32) and rhinitis (n = 23), and from healthy controls (n = 32). Data analysis was performed using QIIME (Quantitative Insights Into Microbial Ecology) v1.8. Significantly higher abundance of Proteobacteria was found in children with rhinitis than in the healthy controls (20.1% vs. 16.1%, P = 0.009). Bacterial species richness (Chao1 index) and diversity (Shannon index) were significantly reduced in children with mite sensitization but not in those with food or IgE sensitization. Compared with healthy children without mite sensitization, the mite-sensitized children with rhinitis and asthma showed significantly lower Chao1 and Shannon indices. Moraxella and Leptotrichia species were significantly found in the interaction of mite sensitization with rhinitis and asthma respectively. Airway microbial diversity appears to be inversely associated with sensitization to house dust mites. A modulation between airway dysbiosis and responses to allergens may potentially cause susceptibility to rhinitis and asthma in early childhood.

  5. The effect of house dust mite sensitization on lung size and airway caliber in symptomatic and nonsymptomatic preadolescent children: A community-based study in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Jedrychowski, W.; Maugeri, U.; Jedrychowska-Bianchi, I.; Mroz, E. [Jagiellonian University, Krakow (Poland)

    2002-06-01

    There are conflicting reports on the effects of atopy on lung function. The purpose of this study was to compare the effects of house mite (HM) atopy on lung function in subsamples of 12-year-old symptomatic and nonsymptomatic preadolescent children taken from the community sample. An additional objective of this study was to identify possible environmental determinants of HM skin reaction. HM sensitization was significantly associated with mother's atopy. It occurred predominantly in boys and was related to the use of coal or gas for house heating. The effect of allergen sensitization on lung size and air-way caliber confined to symptomatic subjects may reflect the inflammatory status of bronchial airways in the symptomatic subjects.

  6. Evaluation of an insecticide dust band treatment method for controlling bed bugs.

    Science.gov (United States)

    Wang, Changlu; Singh, Narinderpal; Cooper, Richard; Liu, Chaofeng; Buczkowski, Grzegorz

    2013-02-01

    Current bed bug, Cimex lectularius L., control usually involves insecticide applications that pose a high risk of insecticide exposure to residents and applicators. To minimize these risks and the amount of insecticides used, we designed and evaluated a dust band treatment technique. The laboratory assay showed that 1% cyfluthrin dust treated bands are highly effective in killing bed bugs. We further evaluated this technique in bed bug infested apartments. The "dust band" treatment consisted of installing a 3.8-cm-wide fabric band on furniture legs and brushing Tempo dust (1% cyfluthrin) (Bayer Environmental Science, Research Triangle Park, NC) onto the bands. In addition, interceptors were installed under furniture legs. Alpine (0.5% dinotefuran) aerosol spray was applied directly to live bed bugs found on furniture during biweekly inspections. This treatment was compared with two other treatments: "integrated pest management" (IPM) and "control." The IPM treatment included dust bands plus the following: applying hot steam to infested furniture and surrounding areas, installing mattress encasements, applying 1% cyfluthrin dust around room perimeters, and installing interceptors under furniture legs. Alpine aerosol was applied to live bed bugs found during biweekly inspections. In the control group, the apartments received cursory treatment with insecticide sprays by the existing pest control contractor hired by the property management office. Bed bug numbers before and after treatments were determined based on biweekly interceptor counts or a combination of interceptor counts and visual inspections. From 0 to 12 wk, mean bed bug counts of the dust band, IPM, and the control treatment decreased by 95, 92, and 85%, respectively. Both dust band and IPM resulted in higher bed bug reduction than the control. There was no significant difference in the final counts between dust band and IPM treatments. An additional field experiment showed installing 1% cyfluthrin dust

  7. Millimeter-wave propagation through a controlled dust environment

    Science.gov (United States)

    Wikner, David

    2007-04-01

    A one-week experiment was conducted to determine the millimeter-wave transmission loss due to dust. Transmission data was collected at 35, 94, and 217 GHz through a recirculating dust tunnel. Dust clouds of various densities were measured during the experiment. The millimeter-wave measurements were non-coherent, using transmitting sources on one side of the dust tunnel and antenna/detectors on the other. The hardware was designed to minimize noise and drift. Even so, it was found that the transmission loss across the 1-m dust tunnel at high dust densities was lower than could be measured accurately with the equipment. Therefore, the results given are limited to system noise and represent maximum transmission losses at the various frequencies. The results show losses less than 0.02 and 0.08 dB for 94 and 217 GHz respectively across one meter of dust with density 3000 mg/m 3. The actual losses are lower and a long baseline interferometer will be required to determine the loss values precisely. Despite the limitations of the experiment, the data show that millimeter-wave imager performance will not be significantly impacted by even a very dense dust cloud.

  8. A Controlled Challenge Study on Di(2-ethylhexyl) Phthalate (DEHP) in House Dust and the Immune Response in Human Nasal Mucosa of Allergic Subjects

    OpenAIRE

    Deutschle, Tom; Reiter, Rudolf; Butte, Werner; Heinzow, Birger; Keck, Tilman; Riechelmann, Herbert

    2008-01-01

    Background Few studies have yet addressed the effects of di(2-ethylhexyl) phthalate (DEHP) in house dust on human nasal mucosa. Objectives We investigated the effects of house dust containing DEHP on nasal mucosa of healthy and house dust mite (HDM)–allergic subjects in a short-term exposure setting. Methods We challenged 16 healthy and 16 HDM-allergic subjects for 3 hr with house dust at a concentration of 300 μg/m3 containing either low (0.41 mg/g) or high (2.09 mg/g) levels of DEHP. Exposu...

  9. Satellite-based Dust Source Identification over North Africa: Diurnal Cycle, Meteorological Controls, and Interannual Variability

    Science.gov (United States)

    Schepanski, Kerstin; Tegen, Ina; Macke, Andreas

    2010-05-01

    frequencies of local dust source activations (DSAF). Dust emission is mainly controlled by the occurrence of strong surface wind speeds and surface conditions like vegetation cover which may differ for individual years depending on the climatic conditions. The role of interannualy changing wind and precipitation pattern for DSAF variability is investigated.

  10. The prevalence of house dust mite (HDM) allergy and the use of HDM-impermeable bed covers in a primary care population of patients with persistent asthma in the Netherlands.

    Science.gov (United States)

    de Vries, M P; van den Bemt, L; van der Mooren, F M; Muris, J W M; van Schayck, C P

    2005-08-01

    : House dust mite (HDM) allergen is one of the most common allergens to which asthma patients are sensitised. Prevalence of HDM allergy varies in the literature. Use of HDM-impermeable bed covers reduces exposure to HDM allergen. The aim of this study was to assess the prevalence of HDM allergy in a primary care population of asthma patients, as well as the use of HDM-impermeable bed covers by these patients. : A random sample of asthma patients between 16 and 60 years old was taken from general practices. Allergy was assessed with a radio allegro sorbent test (RAST). A questionnaire was used to identify demographic characteristics and the actual use of bed covers. : 534 patients were invited and 160 patients participated. 53 patients not willing to participate were randomly selected to test the external validity of our findings. The sample was representative for the primary care asthma population. 48.8% of the asthma population was sensitised to HDM allergen. 25.6% of the HDM-allergic asthma patients were using HDM-impermeable bed covers. : Almost half of the patients with asthma were sensitised to HDM allergen. Only a minority of the patients used HDM-impermeable bed covers.

  11. Estimated crop loss due to coconut mite and financial analysis of controlling the pest using the acaricide abamectin.

    Science.gov (United States)

    Rezende, Daniela; Melo, José W S; Oliveira, José E M; Gondim, Manoel G C

    2016-07-01

    Reducing the losses caused by Aceria guerreronis Keifer has been an arduous task for farmers. However, there are no detailed studies on losses that simultaneously analyse correlated parameters, and very few studies that address the economic viability of chemical control, the main strategy for managing this pest. In this study the objectives were (1) to estimate the crop loss due to coconut mite and (2) to perform a financial analysis of acaricide application to control the pest. For this, the following parameters were evaluated: number and weight of fruits, liquid albumen volume, and market destination of plants with and without monthly abamectin spraying (three harvests). The costs involved in the chemical control of A. guerreronis were also quantified. Higher A. guerreronis incidence on plants resulted in a 60 % decrease in the mean number of fruits harvested per bunch and a 28 % decrease in liquid albumen volume. Mean fruit weight remained unaffected. The market destination of the harvested fruit was also affected by higher A. guerreronis incidence. Untreated plants, with higher A. guerreronis infestation intensity, produced a lower proportion of fruit intended for fresh market and higher proportions of non-marketable fruit and fruit intended for industrial processing. Despite the costs involved in controlling A. guerreronis, the difference between the profit from the treated site and the untreated site was 18,123.50 Brazilian Real; this value represents 69.1 % higher profit at the treated site.

  12. Intestinal proteases of free-living and parasitic astigmatid mites.

    Science.gov (United States)

    Holt, Deborah C; Burgess, Stewart T G; Reynolds, Simone L; Mahmood, Wajahat; Fischer, Katja

    2013-02-01

    Among arthropod pests, mites are responsible for considerable damage to crops, humans and other animals. However, detailed physiological data on these organisms remain sparse, mainly because of their small size but possibly also because of their extreme diversity. Focusing on intestinal proteases, we draw together information from three distinct mite species that all feed on skin but have separately adapted to a free-living, a strictly ecto-parasitic and a parasitic lifestyle. A wide range of studies involving immunohistology, molecular biology, X-ray crystallography and enzyme biochemistry of mite gut proteases suggests that these creatures have diverged considerably as house dust mites, sheep scab mites and scabies mites. Each species has evolved a particular variation of a presumably ancestral repertoire of digestive enzymes that have become specifically adapted to their individual environmental requirements.

  13. Ingestion of milk containing the Dp2 peptide, a dust mite allergen, protects mice from allergic airway inflammation and hyper-responsiveness

    Science.gov (United States)

    2013-01-01

    Background Allergen-specific immunotherapy has been demonstrated to have potential for the treatment of allergic diseases. Transgenic animals are currently the best available bioreactors to produce recombinant proteins, which can be secreted in milk. It has not been clearly demonstrated whether milk from transgenic animals expressing recombinant allergens has immunomodulatory effects on allergic asthma. Methods We aimed to determine whether the oral administration of milk containing a mite allergen can down-regulate allergen-specific airway inflammation. Transgenic CD-1 mice that express a recombinant group 2 allergen from Dermatophagoides pteronyssinus (Dp2) in their milk were generated using an embryonic gene-microinjection technique. Mouse pups were fed transgenic Dp2-containing milk or wild-type milk. Subsequently, these mice were sensitized and challenged with Dp2 to induce allergic airway inflammation. Results Upon sensitization and challenge, mice fed transgenic Dp2 milk had decreased T-helper 2 (Th2) and increased T-helper 1 (Th1) responses in the airway compared with mice fed wild-type milk. Moreover, pre-treatment with transgenic Dp2 milk attenuated airway inflammation and decreased airway hyper-responsiveness. Conclusions This study provides new evidence that oral administration of transgenic milk containing the Dp2 allergen down-regulated and moderately protected against allergic airway inflammation. Milk from transgenic animals expressing allergens may have potential use in the prevention of allergic asthma. PMID:23763898

  14. Coupling the Mars Dust and Water Cycles: Investigating the Role of Clouds in Controlling the Vertical Distribution of Dust During N. H. Summer

    Science.gov (United States)

    Kahre, M. A.; Haberle, R. M.; Hollingsworth, J. L.; Wilson, R. J.

    2014-01-01

    The dust cycle is critically important for the current climate of Mars. The radiative effects of dust impact the thermal and dynamical state of the atmosphere (Gierasch and Goody, 1968; Haberle et al., 1982; Zurek et al., 1992). Although dust is present in the Martian atmosphere throughout the year, the level of dustiness varies with season. The atmosphere is generally the dustiest during northern fall and winter and the least dusty during northern spring and summer (Smith, 2004). Dust particles are lifted into the atmosphere by dust storms that range in size from meters to thousands of kilometers across (Cantor et al., 2001). During some years, regional storms combine to produce hemispheric or planet encircling dust clouds that obscure the surface and raise atmospheric temperatures by as much as 40 K (Smith et al., 2002). Key recent observations of the vertical distribution of dust indicate that elevated layers of dust exist in the tropics and sub-tropics throughout much of the year (Heavens et al., 2011). These observations have brought particular focus on the processes that control the vertical distribution of dust in the Martian atmosphere. The goal of this work is to further our understanding of how clouds in particular control the vertical distribution of dust, particularly during N. H. spring and summer

  15. Utilization of ultrasonic atomization for dust control in underground mining

    Science.gov (United States)

    Okawa, Hirokazu; Nishi, Kentaro; Kawamura, Youhei; Kato, Takahiro; Sugawara, Katsuyasu

    2017-07-01

    This study examined dust suppression using water particles generated by ultrasonic atomization (2.4 MHz) at low temperature (10 °C). Green tuff (4 µm), green tuff (6 µm), kaolin, and silica were used as dust samples. Even though ultrasonic atomization makes fine water particles, raising relative air humidity immediately was difficult at low temperature. However, remaining water particles that did not change to water vapor contributed to suppression of dust dispersion. Additionally, the effect of water vapor amount (absolute humidity) and water particles generated by ultrasonic atomization on the amount of dust dispersion was investigated using experimental data at temperatures of 10, 20, and 30 °C. Utilization of ultrasound atomization at low temperature has the advantages of low humidity increments in the working space and water particles remaining stable even with low relative air humidity.

  16. Prevalencia de la sensibilización a tres ácaros domésticos en la población infantil alérgica de un consultorio médico Prevalence of sensitization to three house dust mites in the allergic infantile population of a family physician's office

    Directory of Open Access Journals (Sweden)

    Mayda González León

    2005-04-01

    Full Text Available Se realizó un estudio con el objetivo de investigar si la sensibilización a estos ácaros ( Dermatophagoides pteronyssinus [ Dp ], Dermatophagoides siboney [ Ds ] y Blomia tropicalis [ Bt ] constituye un problema de salud en nuestra población infantil, pues el estudio de los problemas alérgicos ha identificado a los ácaros domésticos como los principales agentes causales de asma y otras afecciones. Se seleccionaron 32 niños alérgicos de nuestro consultorio que se clasificaron según su grado de exposición al polvo doméstico. A todos se les realizó la prueba por punción cutánea en el brazo derecho, y se utilizaron 3 extractos alergénicos estandarizados Valergen Ò ( Blomia tropicalis, Dermatophagoides siboney y Dermatophagoides pteronyssinus de producción nacional (BIOCEN. La prevalencia de la sensibilización fue mayor de forma significativa (pA study was conducted aimed at investigating if the sensitization to these dust mites (Dermatophagoides pteronyssinus [Dp], Dermatophagoides siboney [Ds] and Blomia tropicalis [Bt] is a health problem in our infantile population, since the study of the allergic problems has identified the house dust mites as the main agents causing asthma and other affections. 32 allergic children of our office were selected and classified according to their degree of exposure to house dust. All of them underwent the skin test in the right arm. 3 standardized allergenic extracts ValergenÒ (Blomia tropicalis, Dermatophagoides siboney y Dermatophagoides pteronyssinus of national production (BIOCEN were used. The prevalence of sensitization was significantly higher (p<0.05 for all the dust mites in patients with a greater exposure to house dust compared with those with lower exposure to it. A higher sensitization was attained for the dust mites of the genus Dermatophagoides. The extract of Dp produced a wheal with a mean size greater than the one caused by other products.

  17. Cloning,expression and purification of dust mite ferritin and its molecular characteristics%粉尘螨铁蛋白的克隆、表达及蛋白特征分析

    Institute of Scientific and Technical Information of China (English)

    林建立; 詹政科; 刘玉琳; 范小琴; 耿晓瑞; 刘晓宇

    2015-01-01

    expressed recombinant plasmid containing ferritin gene was constructed by cloning target gene into pET‐32a and transferred into E .coli Bl21 (DE3) .The ex‐pressed recombinant protein was analyzed by SDS‐PAGE ,and was purified by immobilized metal ion affinity chromatography (IMAC) .The ferritin expressed by dust mite was analyzed by the method of bioinformatics .The recombinant plasmid pET32a‐ferritin was constructed .SDS‐PAGE showed a correct molecular weight of the recombinant ferritin protein .After purification by affinity chromatography ,the protein showed only one strip on SDS‐PAGE gel .SDS‐PAGE showed a band at 20 kD .Dust mite ferritin contains 8 serine kinase ,7 threonine kinase ,7 tyrosine kinase ,and 0 histidine kinase phosphorylation sites .Hy‐drophilic region is larger than the hydrophobic region and it is an unstable protein .In conclusion ,the ferritin gene has been cloned and expressed .The purified ferritin has high purity . The study provides a basis for further study of composition and physicochemical properties of house dust mite allergen .

  18. Evaluation of Mite-Away-II for fall control of Varroa destructor (Acari: Varroidae) in colonies of the honey bee Apis mellifera (Hymenoptera: Apidae) in the northeastern USA.

    Science.gov (United States)

    Calderone, Nicholas W

    2010-02-01

    Mite-Away II, a recently-registered product with a proprietary formulation of formic acid, was evaluated under field conditions in commercial apiaries in upstate New York (USA) for the fall control of Varroa destructor Anderson & Trueman in colonies of the honey bee, Apis mellifera L. Ambient temperatures during the treatment period were in the lower half of the range recommended on the label, but were typical for early fall in upstate New York. Average mite mortality was 60.2 +/- 2.2% in the Mite-Away II group and 23.3 +/- 2.6% in the untreated control group. These means were significantly different from each other, but the level of control was only moderate. These results demonstrate that Mite-Away II may not always provide an adequate level of control even when the temperature at the time of application falls within the recommended range stated on the product's label. To make the best use of temperature-sensitive products, I suggest that the current, single-value, economic treatment threshold be replaced with an economic treatment range. The limits for this range are specified by two pest density values. The lower limit is the usual pest density that triggers a treatment. The upper limit is the maximum pest density that one can expect to reduce to a level below the lower limit given the temperatures expected during the treatment period. When the actual pest density exceeds the upper limit, the product should not be recommended; or, a warning should be included indicating that acceptable control may not be achieved.

  19. Cloning, sequence analysis, and expression of cDNA coding for the major house dust mite allergen, Der f 1, in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Y. Cui

    2008-05-01

    Full Text Available Our objective was to clone, express and characterize adult Dermatophagoides farinae group 1 (Der f 1 allergens to further produce recombinant allergens for future clinical applications in order to eliminate side reactions from crude extracts of mites. Based on GenBank data, we designed primers and amplified the cDNA fragment coding for Der f 1 by nested-PCR. After purification and recovery, the cDNA fragment was cloned into the pMD19-T vector. The fragment was then sequenced, subcloned into the plasmid pET28a(+, expressed in Escherichia coli BL21 and identified by Western blotting. The cDNA coding for Der f 1 was cloned, sequenced and expressed successfully. Sequence analysis showed the presence of an open reading frame containing 966 bp that encodes a protein of 321 amino acids. Interestingly, homology analysis showed that the Der p 1 shared more than 87% identity in amino acid sequence with Eur m 1 but only 80% with Der f 1. Furthermore, phylogenetic analyses suggested that D. pteronyssinus was evolutionarily closer to Euroglyphus maynei than to D. farinae, even though D. pteronyssinus and D. farinae belong to the same Dermatophagoides genus. A total of three cysteine peptidase active sites were found in the predicted amino acid sequence, including 127-138 (QGGCGSCWAFSG, 267-277 (NYHAVNIVGYG and 284-303 (YWIVRNSWDTTWGDSGYGYF. Moreover, secondary structure analysis revealed that Der f 1 contained an a helix (33.96%, an extended strand (17.13%, a ß turn (5.61%, and a random coil (43.30%. A simple three-dimensional model of this protein was constructed using a Swiss-model server. The cDNA coding for Der f 1 was cloned, sequenced and expressed successfully. Alignment and phylogenetic analysis suggests that D. pteronyssinus is evolutionarily more similar to E. maynei than to D. farinae.

  20. Climatic controls on the interannual to decadal variability in Saudi Arabian dust activity: Toward the development of a seasonal dust prediction model

    Science.gov (United States)

    Yu, Yan; Notaro, Michael; Liu, Zhengyu; Wang, Fuyao; Alkolibi, Fahad; Fadda, Eyad; Bakhrjy, Fawzieh

    2015-03-01

    The observed climatic controls on springtime and summertime Saudi Arabian dust activities during 1975-2012 are analyzed, leading to development of a seasonal dust prediction model. According to empirical orthogonal function analysis, dust storm frequency exhibits a dominantly homogeneous pattern across Saudi Arabia, with distinct interannual and decadal variability. The previously identified positive trend in remotely sensed aerosol optical depth since 2000 is shown to be a segment of the decadal oscillation in dust activity, according to long-duration station record. Regression and correlation analyses reveal that the interannual variability in Saudi Arabian dust storm frequency is regulated by springtime rainfall across the Arabian Peninsula and summertime Shamal wind intensity. The key drivers of Saudi Arabian dust storm variability are identified. Winter-to-spring La Niña enhances subsequent spring dust activity by decreasing rainfall across the country's primary dust source region, the Rub' al Khali Desert. A relatively cool tropical Indian Ocean favors frequent summer dust storms by producing an anomalously anticyclonic circulation over the central Arabian Peninsula, which enhances the Shamal wind. Decadal variability in Saudi Arabian dust storm frequency is associated with North African rainfall and Sahel vegetation, which regulate African dust emissions and transport to Saudi Arabia. Mediterranean sea surface temperatures (SSTs) also regulate decadal dust variability, likely through their influence on Sahel rainfall and Shamal intensity. Using antecedent-accumulated rainfall over the Arabian Peninsula and North Africa, and Mediterranean SSTs, as low-frequency predictors, and tropical eastern Pacific and tropical Indian Ocean SSTs as high-frequency predictors, Saudi Arabia's seasonal dust activity is well predicted.

  1. Respiratory function and exposure-effect relationships in wood dust-exposed and control workers.

    Science.gov (United States)

    Holness, D L; Sass-Kortsak, A M; Pilger, C W; Nethercott, J R

    1985-07-01

    The effect of wood dust exposure on 50 cabinet makers was examined. Woodworkers reported more nasal and eye symptoms and more cough, sputum and wheezing than did 49 control workers. More irritated cells were present in the woodworkers' nasal cytological smears. In contrast to the control workers, the woodworkers had a significant decline in lung function over the workshift. An inverse correlation between baseline lung function and an exposure index (mean area dust level multiplied by length of exposure) was demonstrated in the woodworkers. Greater dust exposure was not associated with larger falls in lung function over the work shift.

  2. Transport control of dust particles via the Electrical Asymmetry Effect: experiment, simulation, and modeling

    CERN Document Server

    Iwashita, Shinya; Schulze, Julian; Hartmann, Peter; Donkó, Zoltán; Uchida, Giichiro; Koga, Kazunori; Shiratani, Masaharu; Czarnetzki, Uwe

    2013-01-01

    The control of the spatial distribution of micrometer-sized dust particles in capacitively coupled radio frequency discharges is relevant for research and applications. Typically, dust particles in plasmas form a layer located at the sheath edge adjacent to the bottom electrode. Here, a method of manipulating this distribution by the application of a specific excitation waveform, i.e. two consecutive harmonics, is discussed. Tuning the phase angle \\theta between the two harmonics allows to adjust the discharge symmetry via the Electrical Asymmetry Effect (EAE). An adiabatic (continuous) phase shift leaves the dust particles at an equilibrium position close to the lower sheath edge. Their levitation can be correlated with the electric field profile. By applying an abrupt phase shift the dust particles are transported between both sheaths through the plasma bulk and partially reside at an equilibium position close to the upper sheath edge. Hence, the potential profile in the bulk region is probed by the dust pa...

  3. Efficacy of Metarhizium anisopliae in controlling the two-spotted spider mite Tetranychus urticae on common bean in screenhouse and field experiments.

    Science.gov (United States)

    Bugeme, David Mugisho; Knapp, Markus; Ekesi, Sunday; Chabi-Olaye, Adenirin; Boga, Hamadi Iddi; Maniania, Nguya Kalemba

    2015-02-01

    The efficacy of aqueous and emulsifiable formulations of the fungus Metarhizium anisopliae isolate ICIPE78 was evaluated on the population density of Tetranychus urticae infesting common bean plants under screenhouse and field conditions. Synthetic acaricide abamectin was included as a check. Bean plants were artificially infested with T. urticae and allowed to multiply. Three treatments were applied in the screenhouse and 1 treatment in field trials. Mite density was recorded 2 d before spraying and weekly postspraying. The number of pods per plant, number of seeds per pod, and the dry weight of seeds per plant were recorded only in the screenhouse trials. In both screenhouse and field trials, fungal formulations applied at the concentration of 10(8) conidia/mL and the acaricide reduced the population density of mites as compared to the controls. There were significant differences in T. urticae population densities between the treatments at the various post-spraying sampling dates. In the screenhouse, the mite densities were near zero from 3-week postspraying in the treated leaves. At 4-week postspraying, there were no more leaves in the untreated control (T1) and in the control water + Silwet-L77 (T2). Fungal formulations were as effective as abamectin in reducing mite densities in both screenhouse and field experiments. There were significant differences in the production parameters during the 2 screenhouse trials, with fungal and abamectin treatments generally having the highest yield. Results of this study underline the potential of the M. anisopliae isolate ICIPE78 as an alternative to acaricides for T. urticae management.

  4. Evaluation of airborne methyl salicylate for improved conservation biological control of two-spotted spider mite and hop aphid in Oregon hop yards.

    Science.gov (United States)

    Woods, J L; James, D G; Lee, J C; Gent, D H

    2011-12-01

    The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Homoptera: Aphididae). A 2-year study was conducted to evaluate the recommended commercial use of MeSA in hop yards in Oregon. Slow-release MeSA dispensers were stapled to supporting poles in 0.5 ha plots and these plots were compared to a paired non-treated plot on each of three farms in 2008 and 2009. Across both years, there was a trend for reduced (range 40-91%) mean seasonal numbers of T. urticae in five of the six MeSA-baited plots. Stethorus spp., key spider mite predators, tended to be more numerous in MeSA-baited plots compared to control plots on a given farm. Mean seasonal densities of hop aphid and other natural enemies (e.g., Orius spp. and Anystis spp.) were similar between MeSA-treated and control plots. Variability among farms in suppression of two-spotted spider mites and attraction of Stethorus spp. suggests that the use of MeSA to enhance CBC of spider mites in commercial hop yards may be influenced by site-specific factors related to the agroecology of individual farms or seasonal effects that require further investigation. The current study also suggests that CBC of hop aphid with MeSA in this environment may be unsatisfactory.

  5. Occupational exposure to allergenic mites in a Polish zoo.

    Science.gov (United States)

    Solarz, Krzysztof; Szilman, Piotr; Szilman, Ewa

    2004-01-01

    The study was carried out from April 2000-March 2001. During this period 49 samples of dust, litter, debris and residues from cages and run-offs of mammals, birds and reptiles in the Silesian Zoo, were examined for the presence of mites, especially the allergenic taxa. Mites were extracted using the Berlese method and preserved in 70 % ethanol. For identification, the mites were mounted in Hoyer's medium on microscope slides. Mites were found in 44 of 49 samples analyzed (89.8 %). A total of 5,097 mites were collected, from which 60.3 % were found in samples collected in spring, whereas only 13 % in summer and 24.1 % in autumn. The remaining 2.6 % of the total mite population was found in winter. Majority of mites (82.7 %) were collected from aviaries of macaws and cockatiels (Ara ararauna and Nymphicus hollandicus). A total of 10 species of astigmatid mites were identified that belong to 4 families--Acaridae, Glycyphagidae, Anoetidae and Pyroglyphidae. Generally, the allergenic mites of the order Astigmata constituted 49.5 % of the total count. Among them Acarus farris was predominant (34 % of the total count), followed by Tyrophagus putrescentiae (4.7 %), Caloglyphus sp. (4.35 %) and Acarus immobilis (4.31 %). Dermatophagoides farinae, the house-dust-mite species, was for the first time found in this environment. D. farinae (0.05 % of the total population) was associated with parrots, canids and artiodactyls. Summarizing, it should be stressed, that cages and run-offs of different mammals, aviaries of parrots and terrariums of snakes are important sources of some allergenic mites, especially A. farris and T. putrescentiae, that might cause allergies in workers.

  6. Interplanetary dust particles, not wind blown dust, control high altitude ice clouds on Mars

    Science.gov (United States)

    Hartwick, Victoria; Toon, Owen B.

    2016-10-01

    Water ice clouds on Mars are commonly observed at high altitudes. However, current generation Mars three-dimensional general circulation models (GCM) struggle to reproduce clouds above approximately 20-30 km. On Mars, as on Earth, ice cloud formation likely initiates by heterogeneous nucleation, which requires a population of suspended ice nuclei contiguous with supersaturated atmospheric water vapor. Although supersaturation is observed at high altitudes and has been reproduced in models, models predict very few ice nuclei. The small number of ice nuclei in the upper atmosphere is due to the assumption in Mars GCMs that the only source of ice nuclei is dust from the Martian surface. However, terrestrial mesospheric noctilucent clouds have been shown to form by ice nucleation on particles originating from ablated micrometeroids. Therefore, it is reasonable to assume that a population of micrometeoric ablation biproducts on Mars exists and can act as a site for cloud nucleation at high altitudes. We present simulations using the Community Atmosphere Model for Mars (MarsCAM) based on the National Center for Atmospheric Research (NCAR) Community Atmosphere Model for Earth,coupled with a physically based, state-of-the-art cloud and dust physics model, the Community Aerosol and Radiation Model for Atmospheres (CARMA) to show that ablating micrometeoroids can yield abundant ice nuclei throughout the upper atmosphere of Mars. We find that simulations including a constant annual micrometeoroid flux allows us to reproduce the observed properties of high altitude water ice clouds including vertical distribution and particle size. In general, effective radius decreases with increasing altitude. We have additionally explored the impact of variable ablation rates. Preliminary results suggest that relatively high ablation rates, near or greater than 50%, are required to reproduce observed cloud features.

  7. Proteases and oxidant stress control organic dust induction of inflammatory gene expression in lung epithelial cells.

    Science.gov (United States)

    Natarajan, Kartiga; Gottipati, Koteswara R; Berhane, Kiflu; Samten, Buka; Pendurthi, Usha; Boggaram, Vijay

    2016-10-22

    Persistant inflammatory responses to infectious agents and other components in organic dust underlie lung injury and development of respiratory diseases. Organic dust components responsible for eliciting inflammation and the mechanisms by which they cause lung inflammation are not fully understood. We studied the mechanisms by which protease activities in poultry dust extracts and intracellular oxidant stress induce inflammatory gene expression in A549 and Beas2B lung epithelial cells. The effects of dust extracts on inflammatory gene expression were analyzed by quantitative polymerase chain reaction (qPCR), enzyme linked immunosorbent (ELISA) and western blot assays. Oxidant stress was probed by dihydroethidium (DHE) labeling, and immunostaining for 4-hydroxynonenal (4-HNE). Effects on interleukin-8 (IL-8) promoter regulation were determined by transient transfection assay. Dust extracts contained trypsin and elastase activities, and activated protease activated receptor (PAR)-1 and -2. Serine protease inhibitors and PAR-1 or PAR-2 knockdown suppressed inflammatory gene induction. Dust extract induction of IL-8 gene expression was associated with increased DHE-fluorescence and 4-HNE staining, and antioxidants suppressed inflammatory gene induction. Protease inhibitors and antioxidants suppressed protein kinase C and NF-κB activation and induction of IL-8 promoter activity in cells exposed to dust extract. Our studies demonstrate that proteases and intracellular oxidants control organic dust induction of inflammatory gene expression in lung epithelial cells. Targeting proteases and oxidant stress may serve as novel approaches for the treatment of organic dust induced lung diseases. This is the first report on the involvement of oxidant stress in the induction of inflammatory gene expression by organic dust.

  8. Cloning,Expression, Purification and Immunogenicity of House Dust Mite Allergen Der f5%粉尘螨Der f5克隆表达、纯化和免疫原性鉴定

    Institute of Scientific and Technical Information of China (English)

    袁小惠; 高安健; 邬玉兰; 刘志刚

    2013-01-01

    Objective To clone and express the antigen Der f5 from the dust mite dermatopha-goides farinae ,and to identify its immunogenicity. Methods A pair of primers were designed according to the known sequences of Der f 5 gene .Total RN A was extracted from dust mites and Der f5 gene fragments were amplified by RT-PCR .The PCR product was cloned into pMD18-T vector and transferred into E .coli Top10 .The clones were screened and identified by PCR and restriction enzyme digestion .The target gene obtained from the recombinant plasmid by digestion with Bam H Ⅰ and Hind Ⅲ was connected to the prokaryotic expression vector pET-32a.The expressed recombinant plasmid containing Der f5 gene was constructed by cloning target gene into pET-32a and transferred into E .coli Top10 .The recombinant plasmid was transfected into E .coli strain BL21 (DE3 ) and the transfected cells were grown in the presence of inducer IPTG .The expressed recombinant protein was analyzed by SDS-PAGE and Western blotting and was purified by immo-bilized metal ion affinity chromatography. Results The two recombinant plasmids ,pMD18-T-Der f5 and pET32a-Der f5,were constructed successfully .SDS-PAGE showed a correct molecular weight of the recombinant Der f 5 protein .After purification by affinity chromatography ,the protein showed only one strip on SDS-PAGE gel and appropriate ability to bind to IgE in sera of allergic patients .Conclusion The Der f5 gene has been cloned,expressed and purified and the recombinant Der f5 protein shows appropriate IgE-combined ability . The study provides a basis for specific diagnosis and treatment of dust mite-induced allergic disease.%目的 克隆表达粉尘螨第5组变应原(dermatophagoides farinae,Der f5)基因,并鉴定纯化蛋白免疫原性.方法 根据Der f5 基因已知序列,设计出相应的引物,提取粉尘螨总RNA,采用RT-PCR 方法扩增出Der f5 基因片段,PCR 产物克隆入pMD18-T 载体,转化大肠埃希菌 Top10,经PCR和酶切鉴定

  9. Association study on ADAM33 polymorphisms in mite-sensitized persistent allergic rhinitis in a Chinese population.

    Directory of Open Access Journals (Sweden)

    Ruo-Xi Chen

    Full Text Available BACKGROUND: The ADAM33 gene has been identified as a potentially important asthma candidate gene and polymorphisms in this gene have been shown to be associated with asthma and seasonal allergic rhinitis. OBJECTIVE: To assess whether the ADAM33 polymorphisms are associated with persistent allergic rhinitis (PER due to house dust mites in a Chinese population. METHODS: In a hospital-based case-control study of 515 patients with mite-sensitized PER and 495 healthy controls, we genotyped seven single nucleotide polymorphisms (SNPs in ADAM33. Serum levels of eosinophil cationic protein, total IgE and allergen-specific IgE against Dermatophagoides pteronyssinus and Dermatophagoides farinae were measured by the ImmunoCAP assays. RESULTS: In the single-locus analysis, three polymorphisms, rs3918392 (F1, rs528557 (S2 and rs2787093, were significantly associated with mite-sensitized PER. SNP S2 was associated with significantly increased risk both of asthmatic and nonasthmatic mite-sensitized PER. In the combined genotypes analysis, individuals with 2-4 risk alleles had a significantly higher risk of mite-sensitized PER (adjusted OR = 1.99, 95% CI = 1.50-2.62 than those with 0-1 risk alleles. Haplotype-based association analysis revealed that the ACAGCCT haplotype might have potential to protect against mite-sensitized PER (adjusted OR = 0.67; 95% CI = 0.49-0.90. CONCLUSIONS: Polymorphisms in the ADAM33 gene may contribute to susceptibility of mite-sensitized PER in this Chinese population.

  10. Pollen subsidies promote whitefly control through the numerical response of predatory mites

    NARCIS (Netherlands)

    Nomikou, M.; Sabelis, M.W.; Janssen, A.

    2010-01-01

    Several studies have shown that biological control of pests can be improved by supplying extra food to natural enemies. This increases population levels of the enemies, resulting in decreases in pest densities. In theory, however, supplying food can also have negative effects on biological control.

  11. A review of introductions of pathogens and nematodes for classical biological control of insects and mites

    Science.gov (United States)

    Ann E. Hajek; Michael L. McManus; Italo Delalibera Junior

    2007-01-01

    Compared with parasitoids and predators, classical biological control programs targeting arthropod pests have used pathogens and nematodes very little. However, some pathogens and nematodes that have been introduced have become established and provided excellent control and have been introduced in increasing numbers of areas over decades, often after distributions of...

  12. Palm Kernel Shells as a Dust Control Palliative on an Unpaved Road

    Directory of Open Access Journals (Sweden)

    Peter Ndoke NDOKE

    2006-07-01

    Full Text Available An assessment of the effectiveness of the use palm kernel shells as a dust control palliative on an unpaved road has been carried out. The palm kernel shells were able to reduce the quantity of dust generated from the road to about 75% a few days after the application. It was then suggested that with the absence of funds for road maintenance works organic materials like palm kernel shells could be used as palliatives.

  13. A clinic study on desensitization treatment of bronchial asthma with positive specific IgE to dust mite in children%尘螨特异性IgE阳性儿童支气管哮喘脱敏治疗临床研究

    Institute of Scientific and Technical Information of China (English)

    蔡幸生; 朱勇斌; 林丽爱; 黄育涛; 陈素华; 王金燕; 林彤彤

    2016-01-01

    Objective To investigate the efficacy and the course of desensitization treatment in bronchial asthma with positive specific IgE to dust mite in children. Methods A total of 105 children with bronchial asthma with positive specific IgE to dermatophagoides farinae allergens were randomized into the observation group and the control group. Children in the control group were treated to continue anti-asthma according to the routine of prevention and treatment children with asthma. Chinldren in the observation group were treated by dermatophagoides farinae drops in addition to the treatment of children in the control group. The recurrence of asthma was compared between two groups at 25 weeks post-treatment. At 25 weeks post-treatment , children in the observation group was randomly divided into the observation groupⅠand group Ⅱ. Children in the observation groupⅠreceived continuous treatment except for desensitization treatment. Children in the observation group II received the sublingual immunotherapy with dermatophagoides farinae drops (No.4) for 1 year in addition to the treatment in the observation groupⅠ. The recurrence of asthma was also compared between the two sub-groups. Results The rate and times of recurrence of asthma were lower in the observation group than those in the control group(P 0.05). Conclusion The recurrent rate and frequency of asthma could be reduced by the sublingual immunotherapy with dermatophagoides farinae drops in children with asthma of positive specific IgE to dust mite. The course of treatment may be half year long.%目的:探讨尘螨特异性IgE阳性儿童支气管哮喘脱敏治疗的临床疗效及疗程。方法:105例血清粉尘螨抗原阳性的支气管哮喘患儿在临床缓解后被随机分成观察组和对照组,对照组继续按哮喘诊疗常规进行治疗,观察组在对照组治疗基础上,予粉尘螨滴剂1~4号舌下含服脱敏治疗,治疗满25周时,比较两组哮喘复发情况。25

  14. Comparisons of the allergenic mite prevalence in dwellings and certain outdoor environments of the Upper Silesia (southwest Poland).

    Science.gov (United States)

    Solarz, Krzysztof; Senczuk, Liliana; Maniurka, Hanna; Cichecka, Ewelina; Peszke, Magdalena

    2007-12-01

    The occurrence of allergenic mites (pyroglyphid house-dust mites, acarid and glycyphagid storage mites and others) in dwellings and in synanthropic outdoor sites in a densely populated urban area was investigated. A total of 335 house dust samples were collected from dwellings at 7 different locations in Upper Silesia (Poland), including 84 samples from dwellings of Katowice. Mites were found in 188 of the samples examined (56.1%). A total of 4410 mite specimens were isolated and identified, including 4212 members of the family Pyroglyphidae (95.51%). Among them, Dermatophagoides farinae was predominant (75.3%), followed by D. pteronyssinus (18.6%) and Euroglyphus maynei (1.5%). Moreover, litter soiled with communal wastes was sampled. All 86 samples contained mites. A total of 7547 mite specimens were isolated including 6050 mites known as allergenic (80.5%). Among the astigmatid mites two acarids were dominant: Tyrophagus silvester and T. longior (28.7% and 25.1% of all mites). It should be stressed that 6 of the acarid mite species or genera found in outdoor environments are typical domestic mites (T. putrescentiae), or they have been collected from house dust samples (T. longior, Tyrolichus casei, Thyreophagus entomophagus, Mycetoglyphus fungivorus and Rhizoglyphus robini). The litter of synanthropic sites can therefore form a substantial source of infestation.

  15. Pest species diversity enhances control of spider mites and whiteflies by a generalist phytoseiid predator

    NARCIS (Netherlands)

    Messelink, G.J.; van Maanen, R.; van Holstein-Saj, R.; Sabelis, M.W.; Janssen, A.

    2010-01-01

    To test the hypothesis that pest species diversity enhances biological pest control with generalist predators, we studied the dynamics of three major pest species on greenhouse cucumber: Western flower thrips, Frankliniella occidentalis (Pergande), greenhouse whitefly, Trialeurodes vaporariorum

  16. Parasite-host interactions between the Varroa mite and the honey bee : a contribution to sustainable Varroa control

    NARCIS (Netherlands)

    Calis, J.N.M.

    2001-01-01

    Introduction

    Varroa mites as parasites of honey bees

    Varroa destructor (Anderson & Trueman, 2000), is the most important pest of European races of the Western honey bee, Apis mellifera L., weakening bees

  17. Efficiency of inert mineral dusts in the control of corn weevil

    Directory of Open Access Journals (Sweden)

    Carlos F. Jairoce

    2016-02-01

    Full Text Available ABSTRACT Corn weevil (Sitophilus zeamais may cause great losses in the crop and in stored corn grains. This insect is controlled with the use of chemical insecticides, which may cause serious damage to human health. One alternative of control is the use of inert dusts. The objective of this study was to evaluate the efficiency of inert dusts in the control of S. zeamais under laboratory conditions. The experiment was conducted in 2014, in a completely randomized design, and the treatments consisted of basalt dust with three different granulometries (A, B and C and diatomaceous earth, each of which at the doses of 2 and 4 kg t-1 and a control (no application. Each treatment had four replicates, and the sample unit consisted of 20 g of corn grains infected with 10 adults of S. zeamais kept in temperature-controlled chamber at 25 °C, 70% RH and photophase of 12 h. The dust efficiency was calculated using the equation of Abbott. The mortality rate was higher with the use of diatomaceous earth, reaching 100% after 5 days of exposure and the percentage of control for basalt dusts, 29 days after treatment, was above 80%.

  18. A field demonstration of a modified wet scrubber for dust control in an Illinois coal mine

    Energy Technology Data Exchange (ETDEWEB)

    Chugh, Y.P.; Alam, M.M.; Patwardhan, A.; Thatavarthy, K.K. [Southern Illinois University, Carbondale, IL (United States). Department of Mining and Mineral Resources Engineering

    2005-07-01

    A commercial wet scrubber was used in the SIU-Joy dust control laboratory to test several concepts for improving the dust control efficiency of a wet scrubber. The concepts tested included two filter-two-spray systems, hollow and full-cone sprays, horizontal and vertical sprays, different layer filters and addition of surfactant. The optimised scrubber configuration had water-only vertical sprays for pre-wetting coarse dust, and vertical surfactant-laden water sprays for wetting ultrafine particles. This scrubber configuration reduced dust concentrations from 250 mg/m{sup 3} to 1.8 mg/m{sup 3}. Upon successful testing and optimisation of parameters in the laboratory, field demonstration of the concepts was conducted at an Illinois coal mine. The optimised scrubber configuration was tested in the field with good results in terms of improved visibility in the face area and reduced respirable and quartz dust concentrations. Additional modifications in the field involved relocation of the scrubber suction inlets from the bottom to the side and changing the water spray configuration on the miner head. These additional changes were based on a conceptualised spatial dust distribution profile in the face area. The results of these laboratory development and field demonstration studies are presented in this paper. 6 refs., 11 figs., 4 tabs.

  19. Laboratory screening of potential predators of the poultry red mite (Dermanyssus gallinae) and assessment of Hypoaspis miles performance under varying biotic and abiotic conditions.

    Science.gov (United States)

    Ali, W; George, D R; Shiel, R S; Sparagano, O A E; Guy, J H

    2012-06-08

    The poultry red mite, Dermanyssus gallinae (De Geer), is the most important ectoparasitic pest of layer hens worldwide and difficult to control through 'conventional' synthetic acaricides. The present study aimed to identify a suitable predator of D. gallinae that could potentially form the basis of biological control in commercial poultry systems. From four selected predatory mite species (Hypoaspis miles (Berlese), Hypoaspis aculeifer (Canestrini), Amblyseius degenerans (Berlese) and Phytoseiulus persimilis (Athias-Henriot)), Hypoaspis mites demonstrated the greatest potential as predators of D. gallinae. Experiments were also conducted to assess the effect of environmental (temperature and dust), physical (presence of harbourages) and biological (presence of alternative prey) factors on the predatory efficacy of H. miles. Predation of D. gallinae per se was observed under all conditions tested, though was found to be temperature-dependent and reduced by the presence of alternative prey.

  20. Dust-control for thick-seam wall mines.

    CSIR Research Space (South Africa)

    Belle, BK

    2002-02-01

    Full Text Available the procedures and process used in SIMRAC projects COL 518 and COL 603. 4 List of abbreviations, symbols and terms Abbreviations ARD Airborne Respirable Dust AS Australian Standards AFC Armoured Face Conveyor COM Chamber of Mines CFD Computational Fluid... Loader • Armoured Face Conveyor (AFC) • Roof Supports Figure 2.1 Perspective and close-up views of a longwall mining system (Source: Joy Mining Machinery) Coal Plough: In the early years of longwall mining, the coal plough was widely used...

  1. Effect of Dust Mite Allergen-Specific Immunotherapy Combined with Standardized Management on Prognosis of Asthmatic Children%粉尘螨特异性免疫治疗联合规范化防治在哮喘控制中的作用

    Institute of Scientific and Technical Information of China (English)

    谭永强; 曹兰芳; 沈瑾; 陈柳; 叶桂云; 徐决平

    2011-01-01

    Objective To evaluate the effect of dust mite allergen - specific immunotherapy combined with standardized management on prevention and therapeutic effect in children with asthma. Methods Ninety - five children with established diagnosis of allergic asthma to dust mite were enrolled in this study from Apr. 2005 to Jun. 2010 ,of whom 54 children received treatment with specific immunotherapy(SIT)combined with standardized management (treatment group)for 2- 3 years,and the other 41 cases served as the control group, who received only standardized management( inhaled corticosteroids) at the same time. The clinical symptom and acute episode of the asthmatic children,peak expiratory flow(PEF) and children asthma control test (Ch -CACT), the frequency of respiratory tract infection were detected before and after the treatment,especially the season with high attack rate in 1 year afar the treatment. The data were analyzed by SPSS 15.0 software. Results Compared with control group, the frequency of acute episode, the degree of stable phase of asthma, the dose of inhaled corticosteroids in treatment group after treatment for 1 year were significantly decreased. The PEF and Ch - CACT in both groups were obviously improved and the frequency of respiratory tract infection in both groups after treatment for 1 year were obviously decreased. But the PEF and Ch - CACT in control group were obviously dropped in the season with high attack rate after treatment for 1 year and the average duration of respiratory tract infection in control group were obviously prolonged. Conclusions The dust mite allergen - specific immunotherapy combined with standar-dized management can obviously reduce the frequency and degree of acute episode of asthma, improve the pulmonary function of asthmatic children ,decrease the the frequency and the average duration of respiratory tract infection.%目的 评价粉尘螨特异性免疫治疗联合规范化防治在儿童支气管哮喘(

  2. Dust control products at Hagerman National Wildlife Refuge, Texas: environmental safety and performance

    Science.gov (United States)

    Kunz, Bethany K.; Little, Edward E.

    2015-01-01

    Controlling fugitive dust while protecting natural resources is a challenge faced by all managers of unpaved roads. Unfortunately, road managers choosing between dust control products often have little objective environmental information to aid their decisions. To address this information gap, the U.S. Geological Survey and the U.S. Fish and Wildlife Service collaborated on a field test of three dust control products with the objectives of (a) evaluating product performance under real-world conditions, (b) verifying the environmental safety of products identified as practically nontoxic in laboratory tests, and (c) testing the feasibility of several environmental monitoring techniques for use in dust control tests. In cooperation with refuge staff and product vendors, three products (one magnesium chloride plus binder, one cellulose, and one synthetic fluid plus binder) were applied in July 2012 to replicated road sections at the Hagerman National Wildlife Refuge in Texas. These sections were monitored periodically for 12 months after application. Product performance was assessed by mobile-mounted particulate-matter meters measuring production of fugitive dust and by observations of road conditions. Environmental safety was evaluated through on-site biological observations and leaching tests with samples of treated aggregate. All products reduced dust and improved surface condition during those 12 months. Planned environmental measurements were not always compatible with day-to-day refuge management actions; this incompatibility highlighted the need for flexible biological monitoring plans. As one of the first field tests of dust suppressants that explicitly incorporated biological endpoints, this effort provides valuable information for improving field tests and for developing laboratory or semifield alternatives.

  3. MSHA review of silicosis and dust control in mining

    Energy Technology Data Exchange (ETDEWEB)

    Thaxton, R. [Dept. of Labor, Arlington, VA (United States)

    1996-12-31

    Silicosis has become a forgotten disease. Many miners, when told of the risks of silicosis, indicate that they have never heard of the disease. A 1992 National Institute for Occupational Safety and Health (NIOSH) ALERT, however, pointed out that drilling in rock is hazardous to miners due to exposure to excessive amounts of silica-containing dust. Recent Mine Safety and Health Administration (MSHA) and NIOSH surveys also indicate that silicosis continues to be a significant health risk faced by miners. A joint field study conducted by NIOSH and MSHA in the Johnstown, Pennsylvania area found 8 cases of silicosis among 150 surveyed surface coal miners. Additional x-ray surveillance studies found 6 cases of disease among 234 current and former surface coal miners in the Poteau, Oklahoma area and 3 cases among 66 surface coal miners in the northern West Virginia area. These studies cannot be used to determine quantitative risk, or prevalence of the disease. They do, however, indicate the unacceptable reality that coal miners continue to develop silicosis. Surface miners are not the only miners potentially exposed to levels of silica-containing dust that may lead to development of silicosis. NIOSH and MSHA have received reports of disease among underground coal miners. Several of these cases involve coal miners under age 50. The focus of this presentation is to highlight the specific initiatives undertaken by MSHA`s Coal Mine Safety and Health to address this health hazard.

  4. Dust control in coal faces. Status report; Staubbekaempfung im Strebbetrieb - Stand der Technik

    Energy Technology Data Exchange (ETDEWEB)

    Henke, B. [Deutsche Montan Technologie GmbH, Essen (Germany). Gas and Fire Div.

    2004-07-01

    Dust control in coal faces is of high importance. In shearer faces there are two equivalent techniques of pick spraying systems, the high pressure spraying and the ejector spraying system. Both are forming a fine water droplet jet. High pressure spraying systems are operated with water pressures of about 100 bars, ejector spraying systems with water pressures of about 35 bars. In both cases a nozzle is positioned behind each individual pick. In plough faces the main dust control technique is the plough track spraying system, today in use is the so called 'accompanying spraying system'. It is important, that coarse droplets are formed to enable a stable spray jet in the crossing airflow. The dust control technique for the roof support is the wetting of the canopies. This wetting system is operated time triggered, independent of the movement of the individual supports. By this the crushed material upon the canopies gets homogeneously humidified. (orig.)

  5. RAST studies : IgE antibodies to Dermatogoides pteronyssinus (house dust mite), Aspergillus fumigatus and beta-lactoglobulin in sudden death in infancy syndrome (SDIS).

    Science.gov (United States)

    Turner, K J; Baldo, B A; Hilton, J M

    1975-01-01

    The incidence of 2.5 SDIS cases per 1,000 live births found in Western Australia is in agreement with figures reported for other centres. While the age range of SDIS victims extended from two weeks to 15 months, 57 per cent of deaths occurred in children of two to four months of age. Boys outnumbered girls 1.6:1. Environmental factors are implicated in that the majority of deaths occurred in a biphasic distribution - autumn and late winter months. No significant differences were observed in total IgE levels in serum from SDIS victims, post mortem children who died in trauma of known aetiology and live control children of the same age range. Serum IgE antibodies to D.pteronyssinus were found in 37% of SDIS victims compared with 7% of matched controls (post mortem plus live groups). IgE antibodies to beta-lactoglobulin, the major allergen of cow's milk, appeared with twice the frequency in SDIS vs. control group but both groups showed a similar incidence of antibodies to the allergens of Aspergillus fumigatus. The prevalence of IgE antibodies to D.pteronyssinus in SDIS victims who died in the late winter -- early spring period was double that found in the group who died in the autumn period. Sixtyfour percent of the SDIS victims had antibodies to two or more of the three allergens tested while the control sera were positive to only one allergen. These results support the hypothesis that anaphylaxis induced by immediate hypersensitivity to D.pteronyssinus in particular may be one of the causative factors in SDIS in Western Australia.

  6. House dust mite allergen Der p 1 elevates the release of inflammatory cytokines and expression of adhesion molecules in co-culture of human eosinophils and bronchial epithelial cells.

    Science.gov (United States)

    Wong, Chun K; Li, Mandy L Y; Wang, Cheng B; Ip, Wai K; Tian, Ya P; Lam, Christopher W K

    2006-08-01

    House dust mite (HDM) is a common allergen of allergic asthma. Eosinophils are principal effector cells of allergic inflammation and their adhesion onto human bronchial epithelial cells is mediated by a CD18-intracellular adhesion molecule-1 (ICAM-1)-dependent interaction. We studied the effects of HDM Dermatophagoides pteronyssinus (Der p) 1 on the activation of eosinophils and bronchial epithelial BEAS-2B cells. Cytokines and adhesion molecules were measured using flow cytometry. Transcription factor nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) and signaling molecule p38 mitogen-activated protein kinase (MAPK) were analyzed using electromobility shift assay and western blot, respectively. Der p 1 protein was found to potently induce the release of IL-1beta, IL-6, IL-10, tumor necrosis factor (TNF)-alpha and granulocyte macrophage colony-stimulating factor from eosinophils. Such induction was further up-regulated for IL-6 and IL-10, and down-regulated for TNF-alpha and IL-1beta in eosinophil-BEAS-2B cells co-culture. Surface expression of CD18 and ICAM-1 on eosinophils was greatly increased by Der p 1; such inductive effect on ICAM-1 was also found to be more prominent on BEAS-2B cells from the co-culture than BEAS-2B cells alone. Der p 1 was found to activate NF-kappaB and AP-1 activity in eosinophils alone and in co-culture and BEAS-2B cells in co-culture. Moreover, Der p 1 could activate p38 MAPK in BEAS-2B cells and eosinophils alone and in co-culture. Selective inhibition of NF-kappaB, AP-1 and p38 MAPK resulted in differential suppression of the Der p 1-induced cytokine release and adhesion molecule expression. As an allergen, HDM could therefore induce the release of inflammatory cytokines and expression of adhesion molecules from the interaction of human eosinophils and bronchial epithelial cells.

  7. Der p 1-pulsed myeloid and plasmacytoid dendritic cells from house dust mite-sensitized allergic patients dysregulate the T cell response.

    Science.gov (United States)

    Charbonnier, Anne-Sophie; Hammad, Hamida; Gosset, Philippe; Stewart, Geoffrey A; Alkan, Sefik; Tonnel, André-Bernard; Pestel, Joël

    2003-01-01

    Although reports suggest that dendritic cells (DC) are involved in the allergic reaction characterized by a T helper cell type 2 (Th2) profile, the role of myeloid (M-DC) and plasmacytoid DC (P-DC), controlling the balance Th1/Th2, remains unknown. Here, we showed that in Dermatophagoides pteronyssinus (Dpt)-sensitized allergic patients and in healthy donors, M-DC displayed a higher capacity to capture Der p 1, a major allergen of Dpt, than did P-DC. However, Der p 1-pulsed M-DC from healthy subjects overexpressed CD80 and secreted interleukin (IL)-10, whereas M-DC from allergic patients did not. In contrast, with Der p 1-pulsed P-DC from both groups, no increase in human leukocyte antigen-DR, CD80, and CD86 and no IL-10 secretion were detected. When cocultured with allogeneic naive CD4(+) T cells from healthy donors, Der p 1-pulsed M-DC from allergic patients favored a Th1 profile [interferon (IFN)-gamma(high)/IL-4(low)] and Der p 1-pulsed P-DC, a Th2 profile (IFN-gamma(low)/IL-4(high)). In healthy donors, no T cell polarization (IFN-gamma(low)/IL-4(low)) was induced by Der p 1-pulsed M-DC or P-DC, but in response to Der p 1-pulsed M-DC, T cells secreted IL-10. The neutralization of IL-10 produced by Der p 1-pulsed M-DC from healthy donors led to an inhibition of IL-10 production by T cells and a polarization toward a type 1. Thus, IL-10 produced by M-DC might be an essential mediator controlling the balance between tolerance and allergic status. In addition, P-DC could contribute to the steady state in healthy donors or to the development of a Th2 response in allergic donors.

  8. Effect of Simulant Type on the Absorptance and Emittance of Dusted Thermal Control Surfaces in a Simulated Lunar Environment

    Science.gov (United States)

    Gaier, James R.

    2010-01-01

    During the Apollo program the effects of lunar dust on thermal control surfaces was found to be more significant than anticipated, with several systems overheating due to deposition of dust on them. In an effort to reduce risk to future missions, a series of tests has been initiated to characterize the effects of dust on these surfaces, and then to develop technologies to mitigate that risk. Given the variations in albedo across the lunar surface, one variable that may be important is the darkness of the lunar dust, and this study was undertaken to address that concern. Three thermal control surfaces, AZ-93 white paint and AgFEP and AlFEP second surface mirrors were dusted with three different lunar dust simulants in a simulated lunar environment, and their integrated solar absorptance ( ) and thermal emittance ( ) values determined experimentally. The three simulants included JSC-1AF, a darker mare simulant, NU-LHT-1D, a light highlands simulant, and 1:1 mixture of the two. The response of AZ-93 was found to be slightly more pronounced than that of AgFEP. The increased with fractional dust coverage in both types of samples by a factor of 1.7 to 3.3, depending on the type of thermal control surface and the type of dust. The of the AZ-93 decreased by about 10 percent when fully covered by dust, while that of AgFEP increased by about 10 percent. It was found that / varied by more than a factor of two depending on the thermal control surface and the darkness of the dust. Given that the darkest simulant used in this study may be lighter than the darkest dust that could be encountered on the lunar surface, it becomes apparent that the performance degradation of thermal control surfaces due to dust on the Moon will be strongly dependent on the and of the dust in the specific locality

  9. Efectiveness of Spirodiclofen in the Control of European Red Mite (Panonychus ulmi on Apple and Pear Psylla (Cacopsylla pyri

    Directory of Open Access Journals (Sweden)

    Dejan Marčić

    2007-01-01

    Full Text Available The effectiveness of spirodiclofen, an acaricide and insecticide with a novel mode of action, in protecting apple from the European red mite (Panonychus ulmi and pear from pear psylla (Cacopsylla pyri was tested in field trials in four sites in Serbia in 2004, 2005 and2007. The efficacy of P. ulmi control was investigated at Morović(Šid, where the effects of spirodiclofen were compared with those of fenazaquin, clofentezine, fenpyroximate and bifenthrin. Applied in 2004 at a rate of 0.096 g a.i. L-1 against the overwintering eggs ofP. ulmi, spirodiclofen achieved 86% efficacy, while the efficacies of fenazaquin and clofentezine (25 days after treatment were 84.4% and 27.8%, respectively. In the same season, spirodiclofen displayed high and prolonged efficacy against a summer population of P. ulmi: the efficacy of this acaricide applied at concentrations of 0.096 and 0.144 g a.i. L-1 was 98% and 96.9%, respectively, while fenpyroximate, clofentezine and bifenthrin achieved 43%, 59.5% and 62% efficacy, respectively (45 days after treatment. This effect of spirodiclofen against the summer population was confirmed in the same site in 2005, when 94.9-95.7% efficacy was achieved (47 days after treatment. The efficacy of spirodiclofen, amitraz and abamectin against eggs and larvae of the first generation of C. pyri was examined at a Bela Crkva site in 2004, and in sites at Mandjelos (Sremska Mitrovica and Bela Crkva in 2005. Applied at a concentration of 0.144 g a.i. L-1 at the beginning of hatching, spirodiclofen was found to achieve 83.2-95% efficacy, abamectin 93.5-94.9% and amitraz 78.9-95.6% efficacy (14 days after treatment. Applied in a site at Borkovac (Ruma in 2007 at a rate of 0.096 g a.i.L-1 before hatching of the first generation larvae, spirodiclofen reduced the number of eggs and larvae of C. pyri by 72%, 82% and 89% in evaluations 18, 25 and 38 days after treatment, while abamectin and diflubenzuron achieved reductions of 92%, 95% and

  10. Airtight negative pressure dust-control technology and application of transpersite in the coal conveyer belt system

    Institute of Scientific and Technical Information of China (English)

    MA Yun-dong; JIA Hui-yan; ZHANG Da-ming

    2008-01-01

    Presented a new coal dust control program that was airtight negative pressure dust-control technology at the transpersite,combining with analysis with the movement of air currents and numerical simulation of gas-solid flow at the transpersite,and proved the mechanism of precipitation and proliferation for coal dust-controlt in theory.The technology has made good economic results at the Heidaigou Clean Plant,not only dust concentration control within 10 mg/m3 to the work site,but also substantial energy savings and cost savings.

  11. Prokaryotic Expression of Chimeric Gene Derived from the Group 1 Allergens of Dust Mites and Bioactivity Identification%两种尘螨1类变应原嵌合基因的原核表达及生物活性鉴定

    Institute of Scientific and Technical Information of China (English)

    郭伟; 姜玉新; 李朝品

    2012-01-01

    .05或0.01). 结论 表达了具有低变应原性和高免疫原性的尘螨1类变应原嵌合基因R8.%Objective To express a chimeric gene R8 derived from the group 1 allergens of dust mites using prokaryotic expression system and detect their bioactivities. Methods PCR amplification was performed using specific primers of Derfl gene and the pUCm-T recombinant plasmid containing the R8 chimeric gene as a template. The PCR products were inserted into the pET28a(+) empty vector after double digestion using restriction endonuclease BamH I and Xho I , respectively. The recombinant plasmid was transferred into E. coli line BL21 and induced by 1 mmol/L isopropyl-β-D-l-thiogalactopyranoside (IPTG). The expressed product was detected by SDS-PAGE and the target protein was purified. IgE binding assay of the purified protein R8 was detected by ELISA using dust mite allergic patient sera. For determining immunogenicity of R8 protein, 75 BALB/c mice were randomly divided into 5 groups, namely PBS (negative control), rDer f 1 group and rDer p 1 group (positive groups), R8 group and asthma group. The mice were treated with dust mite extract at 0, 7, 14 day by intraperitoneal injection of allergens (100 μ1, 0.1 μg/μl) and inhaled challenge as aerosol (0.5 μg/ml, 30 min/d) on day 21 for 7 days. Before inhalation in immunotherapy groups at 25-27 day, specific allergen immunotherapy was performed using rDer f 1, rDer p 1 and R8 allergens respectively. Mice in negative control group were treated with PBS all the time. Twenty-four hours after the last challenge, mice in every group were sacrificed. The bron-choalveolar lavage fluid (BALF) was collected. ELISA was used to detect the level of interferon-γ (IFN-γ) and interleukin 4 (IL-4) in BALF. Results SDS-PAGE analysis revealed that chimeric gene R8 was expressed with a band of approximately M, 35 000. Compared with groups of rDer f 1 and rDer p 1 [(80.44±15.50) and (90.79±10.38) μg/ml, respectively], IgE binding capacity

  12. The role of moisture on controlling dust emissions from crusted supply-limited surfaces

    Science.gov (United States)

    King, James; Wiggs, Giles F. S.; Thomas, David S. G.; Washington, Richard

    2013-04-01

    Dust emissions from crusted surfaces are both highly variable and difficult to measure directly. Seasonal changes in surface soil moisture, temperature, evaporation, surface roughness, and sediment supply result in a highly complex surface condition that remains to be fully described in the context of wind erosion potential. A highly intensive project on Makgadikgadi Pan, Botswana using the PI-SWERL (portable wind tunnel) combined with surface measurements of crust and soil properties has led to a new understanding of the time sensitive controls on wind erosion from these surfaces. The PI-SWERL is a highly portable wind tunnel that applies a shear stress to the surface using a motor-controlled rotating annular blade and measures resulting dust emissions with a PM10 monitor (DustTrak TSI Inc.). We undertook a sequence of tests with the PI-SWERL to obtain both the wind erosion threshold (using a slowly increasing shear velocity) and a dust emission flux (using a constant shear velocity) across a 12 km by 12 km grid across the pan surface. A total of just over 1500 wind tunnel tests and 3000 correlated measurements of a variety of surface properties including crust thickness, surface and subsurface soil moisture, shearing strength (shear vane), normal stress resistance (penetrometer), and surface roughness were conducted in August 2011 and August through October 2012. Two sets of results are presented providing discussion on: 1) Spatial variations in surface characteristics 2) Temporal variation in the control of surface characteristics and climatic conditions on potential dust emissions. These results show that wind erosion potential is best described by measurements of normal stress resistance rather than shearing strength at low dust emission fluxes, but despite their frequent use in wind erosion studies of crusted surfaces neither metric provided a good explanation of higher dust emission fluxes. Surface soil moisture explained the most variation in both dust

  13. Dust sources and atmospheric circulation in concert controlling Saharan dust emission and transport towards the Western Mediterranean Basin

    Science.gov (United States)

    Schepanski, Kerstin; Mallet, Marc; Heinold, Bernd; Ulrich, Max

    2017-04-01

    Dust transported from north African source regions towards Europe is a ubiquitous phenomenon in the Mediterranean region, a geographic region that is in part densely populated. Besides its impacts on the atmospheric radiation budget, dust suspended in the atmosphere results in reduced air quality, which is generally sensed as a reduction in quality of life. Furthermore, the exposure to dust aerosols enhances the prevalence of respiratory diseases, which reduces the general human wellbeing, and ultimately results in an increased loss of working hours due to illness and hospitalization rates. Characteristics of the atmospheric dust life cycle that determine dust transport will be presented with focus on the ChArMEx special observation period in June and July 2013 using the atmosphere-dust model COSMO-MUSCAT (COSMO: Consortium for Small-scale MOdeling; MUSCAT: MUltiScale Chemistry Aerosol Transport Model). Modes of atmospheric circulation were identified from empirical orthogonal function (EOF) analysis of the geopotential height at 850 hPa for summer 2013 and compared to EOFs calculated from 1979-2015 ERA-Interim reanalysis. Generally, two different phases were identified. They are related to the eastward propagation of the subtropical ridge into the Mediterranean basin, the position of the Saharan heat low, and the predominant Iberian heat low. The relation of these centres of action illustrates a dipole pattern for enhanced (reduced) dust emission fluxes, stronger (weaker) meridional dust transport, and consequent increase (decrease) atmospheric dust concentrations and deposition fluxes. In concert, the results from this study aim at illustrating the relevance of knowing the dust source locations in concert with the atmospheric circulation. Ultimately, this study addresses the question of what is finally transported towards the Mediterranean basin and Europe from which source regions - and fostered by which atmospheric circulation pattern. Outcomes from this study

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

    Science.gov (United States)

    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 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.

  15. Acaricides and predatory mites against the begonia mite, Polyphagotarsonemus latus (Acari: Tarsonemidae), on Hedera helix.

    Science.gov (United States)

    Audenaert, Joachim; Vissers, Marc; Haleydt, Bart; Verhoeven, Ruth; Goossens, Frans; Gobin, Bruno

    2009-01-01

    In recent years, the begonia mite (Polyphagotarsonemus lotus) has become an important threat to different ornamental cultures in warm greenhouses. At present there are no professional plant protection products registered in Belgium for the control of mites of the Tarsonemidae family. In a screening trial, we evaluated the efficacy of a range of different acaricides: abamectin, milbemectin, pyridaben, spirodiclofen. Based on the results of the screening trial several products were selected for a full efficacy trial following EPPO guidelines. The best control results were obtained with two products from the avermectine group: abamectin and milbemectin. As growers currently have to rely solely on the use of natural enemies there is a strong need for practical evaluation of efficacies of the various predatory mite species (Amblyseius swirskii, A. cucumeris, A. andersoni) used in biological mite control. In a series of experiments, we screened the use of different species of predatory mites. The first efficacy trials on heavily infested plants at different rates of dosage and under different circumstances (temperature, dose rate, application technique) were started in May 2008. In these experiments Amblyseius swirskii showed good efficacy. But temperature was the limiting factor: the predatory mite needed a minimal temperature of 18 degrees C to obtain good results. Further research is necessary to search for predatory mites that can be used in winter conditions (lower temperatures, less light).

  16. A case-control study of wood dust exposure, mutagen sensitivity, and lung cancer risk.

    Science.gov (United States)

    Wu, X; Delclos, G L; Annegers, J F; Bondy, M L; Honn, S E; Henry, B; Hsu, T C; Spitz, M R

    1995-09-01

    The associations between lung cancer risk, mutagen sensitivity (a marker of cancer susceptibility), and a putative lung carcinogen, wood dust, were assessed in a hospital-based case-control study. There were 113 African -American and 67 Mexican-American cases with newly diagnosed, previously untreated lung cancer and 270 controls, frequency-matched on age, ethnicity, and sex. Mutagen sensitivity ( 1 chromatid break/cell after short-term bleomycin treatment) was associated with statistically significant elevated risk for lung cancer [odds ration (OR) = 4.3; 95% confidence intervals (CI) = 2.3-7.9]. Wood dust exposure was also a significant predictor of risk (overall OR = 3.5; CI = 1.4-8.6) after controlling for smoking and mutagen sensitivity. When stratified by ethnicity, wood dust exposure was s significant risk factor for African-Americans (OR = 5.5; CI = 1.6-18.9) but not for Mexican-Americans (OR = 2.0; CI = 0.5-8.1). The ORs were 3.8 and 4.8 for non-small cell lung cancer in Mexican-Americans (CI = 1.2-18.5). Stratified analysis suggested evidence of strong interactions between wood dust exposure and both mutagen sensitivity and smoking in lung cancer risk.

  17. Determinación de sensibilización alérgica a dermatofagoides en niños de 5 años y menores por fluoroinmuno ensayo-UniCAP Dust mite allergic sensitization in children aged 1 month to 5 years-old using specific IgE determination by unicap fluoroimmunoassay

    Directory of Open Access Journals (Sweden)

    ANDREA MEYER K

    2007-06-01

    Full Text Available La sensibilización a dermatofagoides es un factor de riesgo para el desarrollo de asma. Hay escasa información sobre la sensibilización temprana en niños chilenos. Objetivo: Investigar la sensibilización a dermatofagoides en niños de 5 años y menores. Método: Revisión de resultados de IgE específica por ensayo UniCAP (Pharmacia contra dermatofagoides de niños de hasta 5 años con sospecha de alergia respiratoria, divididos en 3 grupos de edad: 1-12 meses, 13-35 meses y 3-5 años. Resultados: Se estudió un total de 224 niños, entre 1 mes y 5 años de edad (x 2,65 años ± 1,48 DS, 57,1% de sexo masculino. Su distribución según grupo etario fue: 66 en el grupo 1; 45 en el grupo 2 y 113 en el grupo 3. El 30,6% presentó sensibilización a dermatofagoides (18,2% grupo 1; 33,3% grupo 2 y 36,3% grupo 3. El grupo 3 presentó concentraciones de IgE específica significativamente más elevadas que los otros grupos. Conclusiones: La sensibilización a dermatofagoides es detectable en menores de un año, con frecuencia y nivel que aumentan en forma paralela a la edadDust mite sensitization is considered a major risk factor for pediatric asthma; however, there are few data about early sensitization in Chilean children available. This study aimed to investigate allergic sensitization to mites in infancy and early childhood. The patient population, 224 children aged 0 to 5 years with suspected respiratory allergy, was divided into 3 groups of age: 1 to 12 months-old, 13 to 35 months-old, and 3 to 5 years-old. Sensitization status was ascertained by assessing the specific IgE to mite by UniCAP fluoroimmunoassay (Pharmacia. Sixty eight (30.6% patients were sensitized to mites. The frequency and level of sensitization increased with the age of the children. Our data support that avoidance measures in the domestic environment aimed at the primary prevention of mite-driven sensitization should be introduced at the earliest possible stage

  18. Tyrophagus putrescentiae mites grown in dog food cultures and the effect mould growth has on mite survival and reproduction.

    Science.gov (United States)

    Canfield, Michael S; Wrenn, William J

    2010-02-01

    The purposes of this study were to determine whether the storage mite, Tyrophagus putrescentiae, could survive and thrive on dog food and if mould growth was important to their survival. All of the chambers (n = 42) were started with 10 female mites and evaluated every other day for mite survival and for the spontaneous development of mould. Ten chambers tested the effect of low moisture on mite survival. Eight chambers were used as positive and negative controls (n = 4 each); positive control mites were fed Fleischmann's((R)) yeast and negative controls had no food source. Three dog foods were evaluated in the same manner. Four chambers had food but mould development was limited by replacing the food kernel every 48 h and four chambers were allowed to grow mould. Mites grown in chambers without moisture died from desiccation within 5 days. The termination point was day 34 when all mites in the negative control group (moisture but no food) died. Although T. putrescentiae survived and grew on all three commercial dog foods, there was no statistically significant difference in mites counts among the dog foods (P dog food. The study demonstrated that the presence of mould positively influences mite viability, while low relative humidity can result in detrimental consequences for T. putrescentiae.

  19. Engineering controls for selected silica and dust exposures in the construction industry--a review.

    Science.gov (United States)

    Flynn, Michael R; Susi, Pam

    2003-04-01

    This literature review summarizes engineering control technology research for dust and silica exposures associated with selected tasks in the construction industry. Exposure to crystalline silica can cause silicosis and lung fibrosis, and evidence now links it with lung cancer. Of over 30 references identified and reviewed, 16 were particularly significant in providing data and analyses capable of documenting the efficacy of various engineering controls. These reports include information on generation rates and worker exposures to silica and dust during four different tasks: cutting brick and concrete block, grinding mortar from between bricks, drilling, and grinding concrete surfaces. The major controls are wet methods and local exhaust ventilation. The studies suggest that while the methods provide substantial exposure reductions, they may not reduce levels below the current ACGIH threshold limit value (TLV) of 0.05 mg/m(3) for respirable quartz. Although further research on controls for these operations is indicated, it is clear that effective methods exist for significant exposure reduction.

  20. Clinical effectiveness of a mite allergen-impermeable bed-covering system in asthmatic mite-sensitive patients.

    NARCIS (Netherlands)

    Bemt, E.A.J.M. van den; Knapen, L. van; Vries, M.P. de; Jansen, M.; Cloosterman, S.G.M.; Schayck, C.P. van

    2004-01-01

    BACKGROUND: Exposure to allergens plays a role in the development of bronchial hyperresponsiveness and in the chronic inflammatory response seen in asthmatic patients. House dust mites (HDMs) are an important source of allergen. Reduction of these allergens might lead to better lung function and red

  1. Evaluation of skin sensitivity in dogs bearing allergic dermatitis to standardized allergenic extract of house dust and storage mites Avaliação da sensibilidade de cães com dermatite alérgica a extratos padronizados de ácaros da poeira domiciliar

    Directory of Open Access Journals (Sweden)

    Victor E.S. Cunha

    2007-08-01

    Full Text Available The objective of the study was to evaluate whether allergenic extracts of five house dust and storage mite species standardized for humans might be used for the diagnosis of canine atopic dermatitis (CAD. Extracts of Dermatophagoides pteronyssinus (Pyroglyphidae, D. farinae (Pyroglyphidae, Blomia tropicalis (Glycyphagidae, Lepidoglyphus destructor (Glycyphagidae and Tyrophagus putrescentiae (Acaridae were evaluated by intradermal testing in 20 healthy dogs (control and 25 dogs with allergic dermatitis. A significant difference in the response was observed between the two groups (pO presente trabalho teve como objetivo avaliar se extratos alergênicos de cinco espécies de ácaros da poeira domiciliar e produtos armazenados, padronizados para humanos, podem ser utilizados no diagnóstico da dermatite atópica canina. Extratos de Dermatophagoides pteronyssinus (Pyroglyphidae, D. farinae (Pyroglyphidae, Blomia tropicalis (Glycyphagidae, Lepidoglyphus destructor (Glycyphagidae e Tyrophagus putrescentiae (Acaridae foram avaliados através de testes intradérmicos em 45 cães, dos quais 20 normais e 25 com dermatite alérgica. Uma diferença significativa foi observada no padrão de respostas obtidas dos dois grupos (p<0.05. Apenas um animal (5% do grupo controle reagiu ao teste cutâneo, enquanto que no grupo dos alérgicos 14 cães (56% apresentaram pelo menos uma reação positiva (odds ratio = 24.2. As maiores freqüências de reações positivas observadas no grupo dos alérgicos foram aos extratos de T. putres-centiae ou L. destructor, cada um induzindo reações em 10(40% cães. Os extratos de D. farinae, D. pteronyssinus e B. tropicalis foram responsáveis por reações positivas em 7(28%, 3(12% e 3(12% cães, respectivamente. Os extratos padronizados para humanos avaliados no presente estudo podem ser utilizados como complemento no diagnóstico da doença, assim como na seleção de alérgenos para a imunoterapia alérgeno-específica.

  2. FasL基因和屋尘螨过敏原基因共表达质粒DNA疫苗对屋尘螨致敏/激发小鼠气道炎症的作用%Effects of DNA vaccine encoding both FasL and house dust mite allergen Der p2 on the airway inflammations in mice sensitized/challenged with house dust mite

    Institute of Scientific and Technical Information of China (English)

    王彦; 林科雄; 王长征; 吴奎; 毕玉田

    2011-01-01

    目的:观察FasL基因和屋尘螨过敏原Der p2基因共表达质粒的DNA疫苗(DNA-FasL-Der p2)对屋尘螨致敏/激发小鼠气道炎症的作用.方法:DNA-FasL-Der p2肌注接种屋尘螨致敏/激发C57BL/6小鼠,再次激发后处死小鼠.观察肺组织病理变化,检测支气管肺泡灌洗液(BALF)细胞总数和分类计数,以及IL-5、IFN-γ水平.并与仅编码Der p2基因的DNA疫苗(DNA-Der p2)比较.结果:接种DNA-FasL-Der p2和DNA-Der p2均能显著减轻屋尘螨致敏/激发小鼠气道炎症.减少BALF中细胞总数和嗜酸粒细胞比例.降低BALF中IL-5水平,以DNA-FasL-Der p2更显著.结论:DNA-FasL-Derp2可有效抑制屋尘螨致敏/激发小鼠气道炎症,而且比DNA-Der p2更有效.%Objective To investigate the effects of DNA vaccine encoding both FasL and house dust mite (HDM) allergen Der p2 (DNA-FasL-Der p2) on the airway inflammation in mice challenged with HDM.Methods HDM sensitized and challenged C57BL/6 mice were immunized with DNA-FasL-Der p2 or DNA-Der p2 (without FasL)DNA vaccine,then they were re-challenged with HDM.Two days after the last challenge, bronchoalveolar lavage fluid (BALF) was collected and lung histology was examined.The levels of IL-5 and IFN-γ in BALF supematants were analyzed by ELISA, total cell count and differential cell count in BALF sediment were determined.Results Both DNA-FasL-Der p2 and DNA-Der p2 relieved airway inflammation and decreased the level of IL-5, total cell count and the percentage of eosinophils in BALF.The improvement of DNA-FasL-Der p2 was more significant than that of DNA-Der p2.Conclusion DNA-FasL-Der p2 could reduce airway allergic inflammation in HDM-challenged mice.And DNA-FasL-Der p2 was more effective than that of DNA-Der p2.

  3. A new design of foam spray nozzle used for precise dust control in underground coal mines

    Institute of Scientific and Technical Information of China (English)

    Han Fangwei; Wang Deming; Jiang Jiaxing; Zhu Xiaolong

    2016-01-01

    In order to improve the utilization rate of foam, an arc jet nozzle was designed for precise dust control. Through theoretical analysis, the different demands of foam were compared amongst arc jets, flat jets and full cone jets when the dust source was covered identically by foam. It is proved that foam consumption was least when an arc jet was used. Foam production capability of an arc jet nozzle under different con-ditions was investigated through experiments. The results show that with the gas liquid ratio (GLR) increasing, the spray state of an arc jet nozzle presents successively water jet, foam jet and mist. Under a reasonable working condition range of foam production and a fixed GLR, foam production quan-tity increases at first, and then decreases with the increase of liquid supply quantity. When the inner diameter of the nozzle is 14 mm, the best GLR is 30 and the optimum liquid supply quantity is 0.375 m3/h. The results of field experiments show that the total dust and respirable dust suppression effi-ciency of arc jet nozzles is 85.8%and 82.6%respectively, which are 1.39 and 1.37 times higher than the full cone nozzles and 1.20 and 1.19 times higher than the flat nozzles.

  4. Dust control at active working places in the Stara Jama coal mine in Zenica

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovic, B.; Kisic, S.

    1984-01-01

    The measures undertaken at a fully mechanized longwall face in the Stara Jama coal mine to reduce the coal dust concentration are described. Dust concentration varies from 16.4 mg/m/sup 3/ ahead of the cutter loader, to 824 mg/m/sup 3/ behind the cutter loader. The cutter loader produced 32,280 mg of coal dust per minute. Since the built-in cutter loader spraying system (80 l/min) was inadequate for dust control, an additional water spraying system with an output of 72 l/min was installed on the cutter loader. In addition, on the bars of the self-advancing powered supports water spraying nozzles with a total capacity of 1.7 l/min each were installed in 4 groups of 20 nozzles each. The angle of water spraying was 120 degrees. These water spraying nozzles are activated by magnetic valves attached to the coal cutter loader when the cutter loader passes the nozzles.

  5. Irradiation as a phytosanitary treatment for mites of the specie Tyrophagus putrescentiae (Acari: Acaridae)

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Valter, E-mail: varthur@cena.usp.b [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil). Lab. de Radiobiologia e Ambiente; Mineiro, Jeferson L.C. [Instituto Biologico de Sao Paulo/APTA, Sao Paulo, SP (Brazil). Lab. de Entomologia Economico

    2009-07-01

    In great populations mites of the specie Tyrophagus putrescentiae can cause damages in stored products. The work had as objective to evaluate the effects of the gamma radiation of the Cobalt-60 to control the mites of the specie T. putrescentiae. The mites were irradiated with doses of 0 (control), 300, 400, 500, 600, 700, 800 Gy, in a source of Cobalt-60 type Gammacell-220, with a dose rate of 0.718 kGy/hour. Each treatment consisted of four repetitions containing 10 mites each, in a total of approximately 40 mites for treatment. The evaluations were daily, being counted the number of mites died, put eggs and emerged larvae. Based on the obtained results it was concluded that the dose sterilizing for the mites of this specie was of 300 Gy. Already the dose of 600 Gy induced the total mortality of the mites after 11 days of the irradiation process. (author)

  6. IPM potentials of microbial pathogens and diseases of mites

    NARCIS (Netherlands)

    van der Geest, L.P.S.; Ciancio, A.; Mukerji, K.G.

    2010-01-01

    An overview is given of diseases in mites, caused by infectious microorganisms. Many pathogens play an important role in the regulation of natural populations of mite populations and are for this reason subject of research on the feasibility to develop such pathogens to biological control agents. Se

  7. IPM potentials of microbial pathogens and diseases of mites

    NARCIS (Netherlands)

    van der Geest, L.P.S.; Ciancio, A.; Mukerji, K.G.

    2010-01-01

    An overview is given of diseases in mites, caused by infectious microorganisms. Many pathogens play an important role in the regulation of natural populations of mite populations and are for this reason subject of research on the feasibility to develop such pathogens to biological control agents.

  8. Ligand selectivity in tachykinin and natalisin neuropeptidergic systems of the honey bee parasitic mite Varroa destructor

    Science.gov (United States)

    The varroa mite, Varroa destructor, is a devastating ectoparasite of the honey bees Apis mellifera and A. cerana. Control of these mites in beehives is a challenge in part due to the lack of toxic agents that are specific to mites and not to the host honey bee. In searching for a specific toxic targ...

  9. The 8-year follow-up of the PIAMA intervention study assessing the effect of mite-impermeable mattress covers

    NARCIS (Netherlands)

    Gehring, U.|info:eu-repo/dai/nl/304831344; de Jongste, J.C.; Kerkhof, M.; Oldewening, M.; Postma, D.; van Strien, R.T.; Wijga, A.H.; Willers, S.M.|info:eu-repo/dai/nl/304834696; Wolse, A.; Gerritsen, J.|info:eu-repo/dai/nl/336510160; Smit, H.A.; Brunekreef, B.|info:eu-repo/dai/nl/067548180

    2012-01-01

    Background: Exposure to high levels of house dust mite (HDM) allergens is associated with the development of allergic sensitization to HDM, a risk factor for the development of asthma, rhinitis, and allergic dermatitis. We studied the effect of an early intervention with mite-impermeable mattress co

  10. Infection of Psoroptes mites with the fungus Metarhizium anisopliae.

    Science.gov (United States)

    Brooks, A J; Wall, R

    2001-01-01

    The astigmatid mite, Psoroptes ovis (Hering) (Acari: Psoroptidae), is an obligatory ectoparasite that causes psoroptic mange in a range of domesticated animals, particularly sheep, where the clinical disease is known as sheep scab. A series of laboratory assays were used to assess the use of the fungus, Metarhizium anisopliae (Metchnikoff) (Deuteromycotina: Hyphomycetes) as a biocontrol agent for P. ovis derived from rabbits (syn. P. cuniculi). The immersion of mites in a suspension of conidia of M. anisopliae resulted in the acquisition of fatal infections. The number of mites which developed infections increased significantly with the increasing concentration of the conidial suspension to which they were exposed; 77% of mites developed infections when exposed to the highest concentration used (1 x 10(8) conidia ml(-1)). Controls developed no fungal infections. Mites allowed simply to walk across a surface which had been treated with a suspension of conidia also acquired fungal infections; the number infected was again related to the concentration of conidia present. After contact for 24 h with a surface treated with 1 x 10(8) conidia ml(-1), 73% of the mites became infected. To determine whether dead infected mites could act as sources of infection, infected cadavers were placed in chambers with live uninfected mites. The uninfected mites acquired fatal infections from the cadavers; a higher ratio of infected cadavers to uninfected mites resulted in greater transmission of infection. The time after death of the infected cadaver was also an important factor influencing the number infected, 5-day-old cadavers were the most infective and 18-day-old cadavers the least infective. The results indicate that M. anisopliae is a good candidate control agent for Psoroptes mites.

  11. Reverse Circulation Drilling Method Based on a Supersonic Nozzle for Dust Control

    Directory of Open Access Journals (Sweden)

    Dongyu Wu

    2016-12-01

    Full Text Available To reduce dust generated from drilling processes, a reverse circulation drilling method based on a supersonic nozzle is proposed. The suction performance is evaluated by the entrainment ratio. A series of preliminary laboratory experiments based on orthogonal experimental design were conducted to test the suction performance and reveal the main factors. Computational fluid dynamics (CFD were conducted to thoroughly understand the interaction mechanism of the flows. The Schlieren technique was further carried out to reveal the flow characteristic of the nozzle. The results show that the supersonic nozzle can significantly improve the reverse circulation effect. A high entrainment ratio up to 0.76 was achieved, which implied strong suction performance. The CFD results agreed well with experimental data with a maximum difference of 17%. This work presents the great potential for supersonic nozzles and reverse circulation in dust control, which is significant to protect the envrionment and people’s health.

  12. Evaluation of Dust Control Technologies for Drywall Finishing Operations: Industry Implementation Trends, Worker Perceptions, Effectiveness and Usability

    OpenAIRE

    Young, Deborah Elspeth

    2007-01-01

    Drywall finishing operations have been associated with worker exposure to dust that contains known particulate respiratory health hazards, such as silica, talc, and mica. Despite the existence of engineering, work-practice, and personal-protective-equipment (PPE) control technologies for the mitigation of this hazard, worker exposures persist in the drywall finishing industry. This research employed a macroergonomic framework to evaluate this problem and identify barriers to dust control ...

  13. Safety of specific immunotherapy with standardized house-dust mite vaccine in asthmatic children%标准化屋尘螨提取液治疗儿童支气管哮喘的安全性研究

    Institute of Scientific and Technical Information of China (English)

    郝创利; 陶慧; 沈美菊; 侯政

    2008-01-01

    目的 通过观察进行标准化屋尘螨特异性免疫治疗(脱敏治疗)的支气管哮喘(简称哮喘)患儿,在脱敏治疗过程中出现的不良反应,评价脱敏治疗的安全性.方法 对在苏州大学附属儿童医院哮喘专科门诊临床确诊的110例哮喘患儿,应用(丹麦ALK-Abell(o)公司安脱达)标准化屋尘螨提取液进行皮下注射脱敏治疗.观察每次注射后不良反应发生情况,统计脱敏治疗的不良反应发生率.结果 在110例患儿共接受免疫注射2332人次,发生局部不良反应291人次(发生率12.48%),其中速发型局部不良反应146人次(6.26%),迟发型局部不良反应145人次(6.22%).局部不良反应在20~800SQU、2000~80 000SQU、100 000 SQU阶段的发生率分别是:1.05%(6/569)、12.05%(97/805)和19.62%(188/958),差异有统计学意义.发生全身不良反应79人次(3.39%),1例次为3级非致命性全身反应,其余均为轻度全身反应(包括哮喘、过敏性鼻炎,过敏性结膜炎、过敏性皮炎),其中速发型全身不良反应49人次(2.10%).迟发型全身不良反应为30人次(1.29%).全身不良反应在20~800 SQU、2 000~80 000 SQU、100 000 SQU阶段的发生率分别是:0.35%(2/569)、6.71%(54/805)和2.51%(24/958),差异有统计学意义.结论 哮喘患儿对标准化屋尘螨提取液特异性免疫治疗耐受性良好.绝大多数局部不良反应为轻度,其发生率随注射提取物浓度增高而增高.全身不良反应绝大多数为轻度,以发生在2 000~80 000 SQU剂量明显上升阶段为最多,在此阶段多加注意.全身不良反应以注射浓度2 000~80 000 SQU为最高.而局部不良反应以100 000 SQU组为最高,提示局部不良反应和全身不良反应不平行.局部不良反应发生不提示全身不良反应发生.%Objective To evaluate the safety of specific immunotherapy(SIT)with standardized house dust mite(HDM)vaccine on allergic asthmatic children.Methods 110 patients with mild to moderate

  14. Using an oxygen content indicator in a coal-dust boiler fuel controller

    Energy Technology Data Exchange (ETDEWEB)

    Y.V. Artamonov; V.N. Barbakov; A.E. Zemlyanoi; K.V. Soldatenko; Y.G. Metal' nikov [Novocherkassk State Regional Electric Power Plant, Novocherkassk (Russian Federation)

    2008-03-15

    The results of installing a circuit for regulating the fuel input to the 300 MW coal-dust power plant at the Novocherkassk State Regional Electric Power Plant (Novocherkasskaya GRES) based on an indicator of the oxygen content in the flue gases are described. The goal is to improve the quality of the controller response to perturbations in the fuel channel. The system and its structure are described, as well as transient control processes in the original and new systems in response to standard perturbations. The regulation quality is at least twice as good in the new scheme.

  15. Experimental investigation on atomization and collecting efficiency of wind-spray dust controller and its parameters optimization

    Institute of Scientific and Technical Information of China (English)

    寇保福; 刘邱祖; 曹世宸; 胡晓禾; 李延峰; 王毅然; 赵波慧

    2015-01-01

    In order to enhance the atomization efficiency of atomizer, a new type of wind-spray dust controller combining the rotary-atomization and colliding broken of droplets was designed by the method of opening the water circulation within the blades. The experiment test for dust controller was conducted by adjusting the following parameters: rotating speed, diversion hole-exit diameter, and colliding tooth angle. Results show that the atomization efficiency increases firstly then decreases with them. And the optimal parameters are obtained with rotating speed 1500−2200 r/min, diversion hole-exit diameter 2−2.5 mm and colliding tooth angle 30°−40°, and under these conditions the corresponding atomization efficiencytops to 95%. Then, the atomization situation under the optimal parameters is held from the aspect of simulation internal flow field and the results of droplet size (30−80μm) are got, which indicates that the conclusion on the optimized parameters of dust controller is reasonable. The collecting efficiencies of different dust concentrations are determined, ranging from 85% to 98.4%, which shows that the designed dust controller can obtain a good atomizing effect and achieve well dustfall efficiency for the wetting dust control of coal mine.

  16. Experimental investigation on atomization and collecting efficiency of wind-spray dust controller and its parameters optimization

    Institute of Scientific and Technical Information of China (English)

    寇保福; 刘邱祖; 曹世宸; 胡晓禾; 李延峰; 王毅然; 赵波慧

    2015-01-01

    In order to enhance the atomization efficiency of atomizer, a new type of wind-spray dust controller combining the rotary-atomization and colliding broken of droplets was designed by the method of opening the water circulation within the blades. The experiment test for dust controller was conducted by adjusting the following parameters: rotating speed, diversion hole-exit diameter, and colliding tooth angle. Results show that the atomization efficiency increases firstly then decreases with them. And the optimal parameters are obtained with rotating speed 1500-2200 r/min, diversion hole-exit diameter 2-2.5 mm and colliding tooth angle 30°-40°, and under these conditions the corresponding atomization efficiency tops to 95%. Then, the atomization situation under the optimal parameters is held from the aspect of simulation internal flow field and the results of droplet size(30-80 μm) are got, which indicates that the conclusion on the optimized parameters of dust controller is reasonable. The collecting efficiencies of different dust concentrations are determined, ranging from 85% to 98.4%, which shows that the designed dust controller can obtain a good atomizing effect and achieve well dustfall efficiency for the wetting dust control of coal mine.

  17. Effect of Illumination Angle on the Performance of Dusted Thermal Control Surfaces in a Simulated Lunar Environment

    Science.gov (United States)

    Gaier, James R.

    2009-01-01

    JSC-1A lunar simulant has been applied to AZ93 and AgFEP thermal control surfaces on aluminum substrates in a simulated lunar environment. The temperature of these surfaces was monitored as they were heated with a solar simulator using varying angles of incidence and cooled in a 30 K coldbox. Thermal modeling was used to determine the solar absorptivity (a) and infrared emissivity (e) of the thermal control surfaces in both their clean and dusted states. It was found that even a sub-monolayer of dust can significantly raise the a of either type of surface. A full monolayer can increase the a/e ratio by a factor of 3 to 4 over a clean surface. Little angular dependence of the a of pristine thermal control surfaces for both AZ93 and AgFEP was observed, at least until 30 from the surface. The dusted surfaces showed the most angular dependence of a when the incidence angle was in the range of 25 to 35 . Samples with a full monolayer, like those with no dust, showed little angular dependence in a. The e of the dusted thermal control surfaces was within the spread of clean surfaces, with the exception of high dust coverage, where a small increase was observed at shallow angles.

  18. Biological control of two-spotted spider mites using phytoseiid predators. Part I. Modelling the predator-prey interaction at the individual level

    NARCIS (Netherlands)

    Sabelis, M.W.

    1982-01-01

    The searching behaviour of individual predators of four phytoseiid species ( Phytoseiulus persimilis , Amblyseius p o tentillae , Amblyseius bibens , Metaseiulus occidentalis ) is investigated in relation to the two-spotted spider mite ( Tetranychus urticae ), which infests greenhouse roses. Especia

  19. Preventing Severe Asthma Exacerbations in Children. A Randomized Trial of Mite-Impermeable Bedcovers.

    Science.gov (United States)

    Murray, Clare S; Foden, Philip; Sumner, Helen; Shepley, Elizabeth; Custovic, Adnan; Simpson, Angela

    2017-07-15

    Allergen exposure in sensitized individuals with asthma interacts with viruses to increase the risk of asthma exacerbation. To evaluate the use of house dust mite-impermeable bedding and its impact on severe asthma exacerbations in children. We randomized mite-sensitized children with asthma (ages 3-17 yr) after an emergency hospital attendance with an asthma exacerbation to receive mite-impermeable (active group) or control (placebo group) bed encasings. Over a 12-month intervention period, the occurrence of severe asthma exacerbations was investigated. Of 434 children with asthma who consented, 286 (mean age, 7.7 yr; male sex, 65.8%) were mite sensitized, and 284 were randomized (146 to the active group and 138 to the placebo group). At 12 months, significantly fewer children in the active group than in the placebo group had attended the hospital with an exacerbation (36 [29.3%] of 123 vs. 49 [41.5%] of 118; P = 0.047). In the multivariable analysis, the risk of emergency hospital attendance was 45% lower in the active group (hazard ratio, 0.55; 95% confidence interval [CI], 0.36-0.85; P = 0.006) than in the placebo group. The annual rate of emergency hospital attendance with exacerbations was 27% lower in the active group than in the placebo group, but this did not reach significance (estimated marginal mean [95% CI], active, 0.38 [0.26-0.56] vs. placebo, 0.52 [0.35-0.76]; P = 0.18). No difference between the groups in the risk of prednisolone use for exacerbation was found (hazard ratio, 0.82; 95% CI, 0.58-1.17; P = 0.28). Mite-impermeable encasings are effective in reducing the number of mite-sensitized children with asthma attending the hospital with asthma exacerbations but not the number requiring oral prednisolone. This simple measure may reduce the health care burden of asthma exacerbations in children. Clinical trial registered with www.isrctn.com (ISRCTN 69543196).

  20. Introduction and evaluation of a novel hybrid brattice for improved dust control in underground mining faces:A computational study

    Institute of Scientific and Technical Information of China (English)

    Kurnia Jundika C.; Sasmito Agus P.; Hassani Ferri P.; Mujumdar Arun S.

    2015-01-01

    A proper control and management of dust dispersion is essential to ensure safe and productive under-ground working environment. Brattice installation to direct the flow from main shaft to the mining face was found to be the most effective method to disperse dust particle away from the mining face. However, it limits the movement and disturbs the flexibility of the mining fleets and operators at the tunnel. This study proposes a hybrid brattice system-a combination of a physical brattice together with suitable and flexible directed and located air curtains-to mitigate dust dispersion from the mining face and reduce dust concentration to a safe level for the working operators. A validated three-dimensional computa-tional fluid dynamic model utilizing Eulerian–Lagrangian approach is employed to track the dispersion of dust particle. Several possible hybrid brattice scenarios are evaluated with the objective to improve dust management in underground mine. The results suggest that implementation of hybrid brattice is beneficial for the mining operation:up to three times lower dust concentration is achieved as compared to that of the physical brattice without air curtain.

  1. 舌下含服粉尘螨疫苗免疫治疗法对哮喘小鼠树突状细胞及NF-κB的影响%Effect of Dust Mite Vaccine Sublingual Immunotherapy on Dendritic Cells and NF-κB in Asthma Mice

    Institute of Scientific and Technical Information of China (English)

    刘晓宇; 蔡科军; 刘志刚; 朱清仙

    2011-01-01

    Objective To investigate the changes in dendritic cells (DCs) and NF-κB before and after sublingual therapy with dust mite vaccine,and to further compare the therapeutic effects of high doses of vaccine and low doses of vaccine in mice with allergic asthma. Methods Sublingual dust mite vaccine was prepared by route method. A total of 28 BALB/c mice were randomly divided into four groups; normal group (group A) .asthma model group (group B),high doses of dust mite vaccine immunotherapy group (group C) and low doses of dust mite vaccine immunotherapy group (group D),with 7 mice in each group. The changes in NF-κB positive cells in lung tissue and 33D1 positive DCs in submandibular lymph nodes after immunotherapy were analyzed by immunohistochemistry and stereology. Airway hyperreactivity was determined, cells contained in bronchoalveolar lavage fluid (BALF) were accounted and classified,and lung inflammation was assayed by HE staining. Results Compared with group B,eosinophil count in BALF,lung inflammatory infiltration and airway hyperreactivity significantly decreased in group C(P<0. 01). Mice in group C and D displayed reduced number density,bulk density and surface area density of 33D1 positive DCs and NF-kB positive cells after immunotherapy, and the reduction in group C was more obvious than that in group D(P<0. 01). Conclusion Sublingual therapy with dust mite vaccine can effectively alleviate the clinical symptoms in the mouse asthma model.and the mechanism is involved in the immunotolerance of DCs and down-regulation of NF-κB.%目的 通过对哮喘模型小鼠舌下含服粉尘螨疫苗进行治疗,研究治疗前后树突状细胞(dendritic cell,DC)和NF-κB在颌下淋巴结和肺部的变化,比较高剂量疫苗和低剂量疫苗对哮喘小鼠的治疗疗效.方法 采用常规方法制备舌下含服粉尘螨疫苗.28只BALB/c小鼠按随机数字表法分为正常组(A组)、哮喘模型组(B组)、粉尘螨高剂量治疗组(C组)、粉尘

  2. Wildlife effects of DDT dust used for tick control on a Texas prairie

    Science.gov (United States)

    George, J.L.; Stickel, W.H.

    1949-01-01

    SUMMARY The effect of DDT dust on wildlife was studied at Camp Bullis, Bexar County, Texas, in the summer of 1947. Studies were made on a 206.6 acre plot that was treated with DDT for experimental control of the Lone Star tick (Amblyomrna americanum). A dust consisting of one part of DDT to nine parts of pyrophyllite was applied at an average rate of 4.4 pounds of DDT per acre. The limits of DDT concentration that affected wildlife cannot be stated exactly because of a heavy rain that fell near the end of the dusting, and because of irregularity in DDT deposition. Since absolute uniformity of dusting could not be expected in any large scale DDT application, the effects observed in these trials were probably fairly representative. However, continued dry weather would have permitted longer exposure to DDT, possibly with more severe effects than those found in this study. The vegetation of the experimental area was roughly 70 percent ungrazed tall-grass prairie and 30 percent trees and shrubs. Ground and bush feeding birds were severely affected. Cardinals, lark sparrows, field sparrows, Bewick's wrens, Carolina wrens, Kentucky warblers, yellow-breasted chats, blue grosbeaks, and painted buntings were nearly or entirely eliminated from the treated area. Birds affected, but less drastically reduced in numbers, were yellow-billed cuckoo, black and white warbler, yellow-throated vireo, and white-eyed vireo. Birds found dead in the DDT area were 9 cardinals, 2 painted buntings, 2 lark sparrows, 1 yellow-breasted chat, and 1 white-eyed vireo. Bird mortality had begun by the day after dusting and was largely over by the end of the fifth day. Census of deer in DDT and check areas before and after treatment showed no reduction in deer numbers and no diminution in use of the DDT area. No deer or fawns were found dead or affected. Box-trapping of raccoons in DDT and check areas before and after treatment showed no effects that could be attributed to DDT. Limited observations on

  3. MITE INCIDENCE AND CROP YIELD IN ZIMBABWE

    African Journals Online (AJOL)

    control, as well as damage and yield of tomatoes were investigated in two important tomato production areas of ... Mutoko, while the pruned and trellised plots had 4.6 and 17.3 mites per leaf. ..... therefore, insecticide deposit on the leaves was.

  4. Effects of dust mite allergen-specific immunotherapy on prevention and cure in children with asthma and allergic rhinitis and the reasons of symptom exacerbation during specific immunotherapy.%粉尘螨特异性免疫治疗变应性哮喘合并鼻炎疗效评价及治疗期间病情反复原因分析

    Institute of Scientific and Technical Information of China (English)

    谭永强; 鲍一笑; 沈瑾; 叶桂云; 陈柳

    2012-01-01

    Objective To evaluate the effects of dust mite allergen-specific immunotherapy combined with standardized management on prevention and cure in children with asthma and allergic rhinitis and analyze the reasons of the asthma and allergic rhinitis symptom exacerbation during specific immunotherapy. Methods One hundred and two children with established diagnosis of allergic asthma and allergic rhinitis to dust mite were enrolled in this study from january 2006 to december 2010, of whom 78 children received the treatment with specific immunotherapy (SIT) combined with standardized management for 2 to 4 year (as the test group) and the other 24 served as the control group with inhaled corticosteroids according to Global Initiative for Asthma (GINA) and Allergic Rhinitis and its Impact on Asthma (ARIA) in the same time. At the beginning, 6 months, 1 year, 2 years of the treament and 1 year after the treament,the clinical symptom and acute episode, pulmonery function (Peak Expiratory Flow, PEF) and Chinese children asthma control test (Ch-CACT) of the asthmatic children, symptem scores and Visual Analogue Scale( VAS) of allergic rhinitis were analyzed, while respiratory tract infection of all the patients were recorded at the second year and after 1 year of the treatment. The reasons of the asthma and allergic rhinitis symptom exacerbation during dust mite allergen-specific immunotherapy were analyzed. The data were analyzed by SPSS15.0. Results Compared with control group, the frequency of acute episode, the frequency of respiratory tract infection in test group were significantly decreased at the 2 years of the treament and 1 year after the treament. The PEFof asthmasic children were obviously improved in the test group at the 2 years of the treament and 1 year after the treament and the Ch-CACT were more higher in the test group than the control group at 1 year after the treament. Compared with control group, the symptem scores and VAS of allergic rhinitis were

  5. Allergens of mites

    Directory of Open Access Journals (Sweden)

    Emilia Siwak

    2014-04-01

    Full Text Available Mite allergens belong to the group of inhalant allergens and represent antigenic substances which are particutlarly important in the pathogenesis of respiratory system diseases and skin diseases. The most common diseases associated with chronic exposure to these aeroallergens include: allergic rhinitis, bronchial asthma and atopic dermatitis. Mite allergens are simple proteins or glycoproteins with different molecular structures and various biochemical functions. The sensitizing capacity of these proteins is connected from their physicochemical properties. Individual allergens perform, among others, the functions of structural proteins, act as enzymes, transport lipids, bind metal ions, and are capable of glycosylation. In addition, mite allergenic proteases degrade proteins of the skin epithelium-resulting in a weakening of its natural protective barrier-and induce the immune response. The proteases also induce the release of pro-inflammatory cytokines: interleukin-4 (IL-4, interleukin 6 (IL-6, interleukin 8 (IL-8, eotaxin, and granulocyte-macrophage colony-stimulating factor-GM-CSF. The article presents the tertiary structure of major and mid-range mite allergens and their classification. Based on literature reports concerning the chemical structure of allergenic proteins, it was emphasized that the structural differences between homologous proteins with allergenic pozoproperties relate to the distribution of amino acid residues on the surface of the molecule. IgE binding affinity and the similarities and differences in the amino acid sequence of the allergens were also the basis for determining cross-reactivity of allergenic proteins. The paper shows an example of this phenomenon, describing the existence of common allergens for various mite species.

  6. Effectiveness of house dust mite acaricide tri-n-butyl tin maleate on carpets, fabrics and mattress foam: a standardization of methodology Eficácia do acaricida maleato de estanho tri-n-butílico contra ácaros de poeira em carpetes, tecidos e espuma de colchão: padronização de metodologia

    Directory of Open Access Journals (Sweden)

    Satiko Uehara

    2006-06-01

    Full Text Available The aim of this study was to determine the effectiveness of the acaricide tri-n-butyl tin maleate, industrially applied to samples of carpets, mattress foam, and fabrics used for furniture upholstery, soft toys and shoe uppers. Approximately 100 adult house dust mites of the species Dermatophagoides pteronyssinus were inoculated into a Petri dish containing the sample (a piece of carpet, mattress foam, or fabric, treated with the acaricide, randomly collected. Mite-maintenance culture medium was added on top of each sample. After one, two, three, seven and 30 days of incubation at 25 ºC and 75% relative humidity, each dish was examined using a 40X stereoscopic microscope (40X. One hundred percent acaricide effectiveness was obtained in treated materials by the end of the 30th-day postinoculation period, under optimal conditions for mite maintenance.O objetivo do presente estudo foi verificar a eficácia do acaricida maleato de estanho tri-n-butílico, aplicado industrialmente em amostras de carpetes, tecidos de revestimentos de móveis e de calçados, assim como de espumas de colchão. Aproximadamente 100 ácaros adultos da espécie Dermatophagoides pteronyssinus foram inoculados em placa de Petri contendo a amostra (pedaço de colchão, tecido ou carpete, tratada com o produto acaricida, coletados aleatoriamente. Foi acrescentado sobre a amostra, meio de cultivo para a manutenção dos ácaros. Cada placa foi examinada após 1, 2, 3, 7 e 30 dias de incubação a 25 ºC e 75% de U.R.A. (umidade relativa do ar, sob microscópio estereoscópico com 40X de aumento. O acaricida maleato de estanho tri-n-butílico apresentou 100% de eficácia acaricida após 30 dias da aplicação, em condições ótimas para a manutenção dos ácaros.

  7. The effect of cleanliness control during installation work on the amount of accumulated dust in ducts of new HVAC installations.

    Science.gov (United States)

    Holopainen, R; Tuomainen, M; Asikainen, V; Pasanen, P; Säteri, J; Seppänen, O

    2002-09-01

    The aim of this study was to evaluate the amount of dust in supply air ducts in recently installed ventilation systems. The samples for the determination of dust accumulation were collected from supply air ducts in 18 new buildings that have been constructed according to two different cleanliness control levels classified as category P1 (low oil residues and protected against contaminations) and category P2, as defined in the Classification of Indoor Climate, Construction and Building Materials. In the ducts installed according to the requirements of cleanliness category P1 the mean amount of accumulated dust was 0.9 g/m2 (0.4-2.9 g/m2), and in the ducts installed according to the cleanliness category P2 it was 2.3 g/m2 (1.2-4.9 g/m2). A significant difference was found in the mean amounts of dust between ducts of categories P1 and P2 (P < 0.008). The cleanliness control procedure in category P1 proved to be a useful and effective tool for preventing dust accumulation in new air ducts during the construction process. Additionally, the ducts without residual oil had lower amounts of accumulated dust indicating that the demand for oil free components in the cleanliness classification is reasonable.

  8. Particle Removal by Electrostatic and Dielectrophoretic Forces for Dust Control During Lunar Exploration Missions

    Science.gov (United States)

    Calle, C. I.; Buhler, C. R.; McFall, J. L.; Snyder, S. J.

    2009-01-01

    Particle removal during lunar exploration activities is of prime importance for the success of robotic and human exploration of the moon. We report on our efforts to use electrostatic and dielectrophoretic forces to develop a dust removal technology that prevents the accumulation of dust on solar panels and removes dust adhering to those surfaces. Testing of several prototypes showed solar shield output above 90% of the initial potentials after dust clearing.

  9. Age-related changes in the behavioural response of honeybees to Apiguard®, a thymol-based treatment used to control the mite Varroa destructor.

    Science.gov (United States)

    Mondet, Fanny; Goodwin, Mark; Mercer, Alison

    2011-11-01

    The parasitic mite Varroa destructor is responsible for heavy losses in honey bee colonies and represents a major threat to the beekeeping industry. Essential oils offer an attractive alternative to the use of synthetic chemicals for the control of varroa. Amongst them, thymol appears to be particularly promising. However, treatments using thymol as their active substance, such as the gel formulation Apiguard(®), are suspected to have adverse effects on honey bee colonies. In this study, laboratory assays are used to investigate the effects of Apiguard(®) exposure on honey bee behaviour. Our results reveal that honey bee responses to this anti-varroa treatment change with honey bee age. While 2-day-old bees respond neutrally to Apiguard(®), older bees generally avoid the Apiguard(®) gel. Responses of forager bees were particularly striking. Foragers appear to be repelled by Apiguard(®). Touching their antennae with Apiguard(®) induces robust fanning behaviour. Our data suggest, however, that forager bees exposed to Apiguard(®) in the hive can become habituated to this treatment. These results offer interesting new perspectives on the effects of Apiguard(®) on honey bee behaviour and serve to highlight age-related changes in honey bee responses to gustatory, as well as olfactory cues.

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

    Science.gov (United States)

    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.

  11. Comparative Studies on Control Effect of Rosmarinus officinalis L. and Formic Acid on Bee Mites%迷迭香和甲酸对蜜蜂寄生螨防治效果比较研究

    Institute of Scientific and Technical Information of China (English)

    赵洪木; 卢焕仙

    2011-01-01

    [ Objective ]The study aimed to compare the control effect of Rosmarinus officinalis L. and formic acid on the bee mites. [ Method ]The formic acid was matched into 80% acid solution by adding the water to conduct the treatment by fumigating kill on the bee mite and R. officinalis was extract into the extracting solution by using water extraction to conduct the touch treatment by spraying on the bee mite, with no drug treatment as the CK. The death condition of bee mite after treatment for 24 and 48 h and the changes of bee mite parasitic rate after treatment for 14,21 and 7 d were counted. [ Result ]The deaths of bee mites treated through the fumigating kill by the formic acid and through the touch kill by R. officinalis for 24 and 48 h were higher than CK. Statistics showed that the effect of formic acid had the extremely significant difference with that of R. officinalis and CK and the effect of R. officinalis had no significant difference with that of CK. The parasitic rate of bee mites treated by the formic acid and R. officinalis for 7,14 and 21 d were all decreased while the that of CK was rose,in which,the parasitic rate of bee mites in R. officinalis group with 5 swarm of bees was decreased by 13.3% - 3.4% and that in formic acid group was decreased by 26.7% - 10.0%.Statistics showed that the effects of formic acid and R. officinalis had extremely significant difference with that of CK after drug application for 21 d. [ Conclusion ] After 21 d treatment,R. officinalis and the formic acid all could make the parasitic rate of bee mite dropped significantly ,so R.officinalis can be used as the alternative medicine of acaricidal agent from the pollution-free plant source.%[目的]比较迷迭香和甲酸对蜂螨的治疗效果.[方法]将甲酸加水配成80%溶液,对蜂螨进行熏杀治疗,采用水提法提取迷迭香提取液,对蜂螨进行喷雾触杀治疗,不作药物治疗为对照,计算处理后24、48 h蜂

  12. AIR POLLUTION CONTROL THROUGH KILN RECYCLING BY-PASS DUST IN A CEMENT FACTORY

    Directory of Open Access Journals (Sweden)

    F. Mohsenzadeh, J. Nouri, A. Ranjbar, M. Mohammadian Fazli, A. A. Babaie

    2006-01-01

    Full Text Available Air pollution is a major problem in the industrial areas. Cement dust is one of the important environmental pollutants. In this study the possibility of dust recycling especially kiln dust which has significant importance regarding air pollution in the cement plant, was examined. Tehran cement factory is one of the most important Iranian factories which is located in Tehran. This factory produces high volume of pollutants that are released to in environment. The possibility of reusing of kiln by pass returned dust has been examined in this factory. Different percentages of kiln by-pass dust of this factory were added to products and outcomes of its presence in parameters such as chemical compound, granulation, primary and final catch time, volume expansion, consumed water and resistance of mortar were surveyed. The result indicated that by adding the amounts of 3-8 dust the mortar resistance increase, but adding more than 15%, the mortar resistance has been decreased. Survey in consumed water proved that adding dust to cement, the trend for consuming water is decreased. After dust addition dust, primary and final catch time were compared in different samples and data which showed decrease in dust added samples. Cements with dust added showed increase in auto clave expansion. Overally, results proved that, the best percentage rate of dust addition to the cement was 15%.

  13. Regional and climatic controls on seasonal dust deposition in the southwestern U.S.

    Science.gov (United States)

    Reheis, M.C.; Urban, F.E.

    2011-01-01

    Vertical dust deposition rates (dust flux) are a complex response to the interaction of seasonal precipitation, wind, changes in plant cover and land use, dust source type, and local vs. distant dust emission in the southwestern U.S. Seasonal dust flux in the Mojave-southern Great Basin (MSGB) deserts, measured from 1999 to 2008, is similar in summer-fall and winter-spring, and antecedent precipitation tends to suppress dust flux in winter-spring. In contrast, dust flux in the eastern Colorado Plateau (ECP) region is much larger in summer-fall than in winter-spring, and twice as large as in the MSGB. ECP dust is related to wind speed, and in the winter-spring to antecedent moisture. Higher summer dust flux in the ECP is likely due to gustier winds and runoff during monsoonal storms when temperature is also higher. Source types in the MSGB and land use in the ECP have important effects on seasonal dust flux. In the MSGB, wet playas produce salt-rich dust during wetter seasons, whereas antecedent and current moisture suppress dust emission from alluvial and dry-playa sources during winter-spring. In the ECP under drought conditions, dust flux at a grazed-and-plowed site increased greatly, and also increased at three annualized, previously grazed sites. Dust fluxes remained relatively consistent at ungrazed and currently grazed sites that have maintained perennial vegetation cover. Under predicted scenarios of future climate change, these results suggest that an increase in summer storms may increase dust flux in both areas, but resultant effects will depend on source type, land use, and vegetation cover. ?? 2011.

  14. Environmental factors controlling the seasonal variability in particle size distribution of modern Saharan dust deposited off Cape Blanc

    Science.gov (United States)

    Friese, Carmen A.; van der Does, Michèlle; Merkel, Ute; Iversen, Morten H.; Fischer, Gerhard; Stuut, Jan-Berend W.

    2016-09-01

    The particle sizes of Saharan dust in marine sediment core records have been used frequently as a proxy for trade-wind speed. However, there are still large uncertainties with respect to the seasonality of the particle sizes of deposited Saharan dust off northwestern Africa and the factors influencing this seasonality. We investigated a three-year time-series of grain-size data from two sediment-trap moorings off Cape Blanc, Mauritania and compared them to observed wind-speed and precipitation as well as satellite images. Our results indicate a clear seasonality in the grain-size distributions: during summer the modal grain sizes were generally larger and the sorting was generally less pronounced compared to the winter season. Gravitational settling was the major deposition process during winter. We conclude that the following two mechanisms control the modal grain size of the collected dust during summer: (1) wet deposition causes increased deposition fluxes resulting in coarser modal grain sizes and (2) the development of cold fronts favors the emission and transport of coarse particles off Cape Blanc. Individual dust-storm events throughout the year could be recognized in the traps as anomalously coarse-grained samples. During winter and spring, intense cyclonic dust-storm events in the dust-source region explained the enhanced emission and transport of a larger component of coarse particles off Cape Blanc. The outcome of our study provides important implications for climate modellers and paleo-climatologists.

  15. Impeding movement of the poultry red mite, Dermanyssus gallinae.

    Science.gov (United States)

    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.

  16. Weed management practices affect the diversity and relative abundance of physic nut mites.

    Science.gov (United States)

    Saraiva, Althiéris de Sousa; Sarmento, Renato A; Erasmo, Eduardo A L; Pedro-Neto, Marçal; de Souza, Danival José; Teodoro, Adenir V; Silva, Daniella G

    2015-03-01

    Crop management practices determine weed community, which in turn may influence patterns of diversity and abundance of associated arthropods. This study aimed to evaluate whether local weed management practices influence the diversity and relative abundance of phytophagous and predatory mites, as well as mites with undefined feeding habits--of the families Oribatidae and Acaridae--in a physic nut (Jatropha curcas L.) plantation subjected to (1) within-row herbicide spraying and between-row mowing; (2) within-row herbicide spraying and no between-row mowing; (3) within-row weeding and between-row mowing; (4) within-row weeding and no between-row mowing; and (5) unmanaged (control). The herbicide used was glyphosate. Herbicide treatments resulted in higher diversity and relative abundance of predatory mites and mites with undefined feeding habit on physic nut shrubs. This was probably due to the toxic effects of the herbicide on mites or to removal of weeds. Within-row herbicide spraying combined with between-row mowing was the treatment that most contributed to this effect. Our results show that within-row weeds harbor important species of predatory mites and mites with undefined feeding habit. However, the dynamics of such mites in the system can be changed according to the weed management practice applied. Among the predatory mites of the family Phytoseiidae Amblydromalus sp. was the most abundant, whereas Brevipalpus phoenicis was the most frequent phytophagous mite and an unidentified oribatid species was the most frequent mite with undefined feeding habit.

  17. Comparison of nasal responsiveness to histamine, methacholine and phentolamine in allergic rhinitis patients and controls

    NARCIS (Netherlands)

    R. Gerth van Wijk (Roy); P.H. Dieges

    1987-01-01

    textabstractIn a selected group of rhinitis patients with an IgE‐mediated allergy to house dust mites the nasal response to insufflation of histamine chloride, methacholine and phentolamine was demonstrated to be higher than in a control group. With the methods used histamine chloride was better at

  18. Comparison of nasal responsiveness to histamine, methacholine and phentolamine in allergic rhinitis patients and controls

    NARCIS (Netherlands)

    R. Gerth van Wijk (Roy); P.H. Dieges

    1987-01-01

    textabstractIn a selected group of rhinitis patients with an IgE‐mediated allergy to house dust mites the nasal response to insufflation of histamine chloride, methacholine and phentolamine was demonstrated to be higher than in a control group. With the methods used histamine chloride was better at

  19. Breeding the Mite-Resistant Honeybee by Nutritional Crossbreed Technology

    Institute of Scientific and Technical Information of China (English)

    XIE Xian-bing; PENG Wen-jun; ZENG Zhi-jiang

    2008-01-01

    Mite (Varroa destructor) is one of the most serious parasite threats to the honey bee (Apis mellifera) reared in China. The beekeepers mainly use the drug to control and kill the mite in the past years, but the honey products may be contaminated and the mite is becoming drug-resistant. The main idea of this paper is to research the possibility of mite-resistant honeybee rearing by nutritional crossbreed. The larvae (Apis mellifera ligustica) are bred with the royal jelly of Apis carana carana, and then the morphological index of the worker generation, genotypic frequency and gene frequency of the MDH Ⅱ, genetic resemblance, and mite resistance are measured. The results show that: compared to the parent workers, the proboscis length, anterior wing area, the total length of the third and fourth dorsal plate of the abdomen, the length of the fourth dorsal plate of the tuberculum, the area of the sixth abdominal segment, and the area of wax mirrors are significantly different, but the differences in the brachium index, dactylus index, and wing claw are not significant. Moreover, there are some mutations in the genotypic frequency and gene frequency of the MDH Ⅱ. The mite resistance of the nutritional crossbreed worker is significantly higher. The morphological, physical, and biochemical characters, genetic resemblance, and the mite-resistant ability of the worker generation can be changed by nutritional crossbreeding. Nutritional crossbreeding can be a new way to breed the honeybee.

  20. Controlling the coal dust at transshipment point:A study of the foam-sol foaming device

    Institute of Scientific and Technical Information of China (English)

    Xi Zhilin; Jiang Manman; Sun Changping; Tu Xian

    2014-01-01

    In order to effectively control the dust at the transshipment point with foam-sol, this paper attempted to study the characteristics of dust diffusion at transshipment point and the foam-sol foaming device with diffusion outlet was also designed in this paper. To study the diffusion rules of coal dust, fluent discrete phase model was utilized in the numerical simulation, as the coal dust was thrown down at a horizontal velocity of 2.5 m/s. A foam-sol foaming device was designed, through which foaming agent could be auto-matically sucked into the Venturi by the negative pressure. The automatic controller was also equipped, which could transform the energy of the compressed air into the constant pressure difference so that the gelling agent could be qualitatively added into the gel container. The diffusion outlet that could spray out foam-sol in a continuous, conical and 3D manner was also designed. Moreover, this paper also carried out the contrast experiments on dust removal efficiency among water, aqueous foam and foam-sol. The results clearly show that the symmetrical whirlpools appeared below the inlet where the largest whirl-pool diameter was 0.52 m, and the horizontal distance from swirl range to the inlet was approximately 0.69 m. By using the self-designed foaming device, the foaming was multiplied by 30 times and the vol-ume ratio with water and foaming agent reached 95%:5%. In this context, the gas pressure was controlled at 0.3 MPa, with gas flow at 15 m3/h and water flow at 0.5 m3/h, with water pressure controlled between 0.34 and 0.36 MPa. The foam-sol has the highest dust removal efficiency than other agents.

  1. Parasitic mites of Surinam XXXIII. Feather mites (Analgoidea)

    NARCIS (Netherlands)

    Černý, V.; Lukoschus, F.S.

    1975-01-01

    The mites listed in the present paper have been collected from July to October 1971 by the junior author and Drs. N. J. J. KOK during their stay in Surinam with financial aid of the Netherlands Foundation for the Advancement of Tropical Research (WOTRO). Mites have been collected occasionally mainly

  2. The impact of pesticides on apple mite communities

    OpenAIRE

    Ahmad, Shakeel

    2013-01-01

    Laboratory, field and semi-field experiments have been carried out on the predatory mites Kampimodromus aberrans, Amblyseius andersoni, Typhlodromus pyri and Phytoseius finitimus in order to optimize biological control strategies against phytophagous mites in apple orchards. The first experiment concerned the augmentative releases of K. aberrans in organic and conventional apple orchards. The most frequent insecticides used in organic orchards were pyrethrins and spinosad, whereas neonicotino...

  3. Proteases and oxidant stress control organic dust induction of inflammatory gene expression in lung epithelial cells

    OpenAIRE

    Natarajan, Kartiga; Gottipati, Koteswara R.; Berhane, Kiflu; Samten, Buka; Pendurthi, Usha; Boggaram, Vijay

    2016-01-01

    Background Persistant inflammatory responses to infectious agents and other components in organic dust underlie lung injury and development of respiratory diseases. Organic dust components responsible for eliciting inflammation and the mechanisms by which they cause lung inflammation are not fully understood. We studied the mechanisms by which protease activities in poultry dust extracts and intracellular oxidant stress induce inflammatory gene expression in A549 and Beas2B lung epithelial ce...

  4. Host-parasite interaction and impact of mite infection on mosquito population

    Directory of Open Access Journals (Sweden)

    Atwa A. Atwa

    Full Text Available ABSTRACT During the present study, the host-parasite relationship between mosquitoes and parasitic mites was investigated. The 8954 individuals of male and female mosquitoes belonging to 26 genera: seven each of Aedes and Culex, six of Anopheles and one each of Toxorhynchites, Coquillettidia and Uranotaenia were collected from 200 sites. The male and female mosquitoes were collected from the State of Uttar Pradesh, located at 26.8500° N, 80.9100° E in North India by deploying Carbon dioxide-baited and gravid traps. The intensity of mite's infection, type and number of mites attached to mosquitoes, mite's preference for body parts and host sexes were the parameters used to determine host-parasite relationship. Eight species of mites: Arrenurus acuminatus, Ar. gibberifrons, Ar. danbyensis, Ar. madaraszi, Ar. kenki, Parathyas barbigera, Leptus sp., and Anystis sp., parasitized mosquitoes. Parasitic mites preferred host's thorax for attachment as compared to the head, pre-abdomen or appendages. The present study suggests phoretic relationship between parasitic mites and mosquitoes. Wide occurrence, intensity of infection, parasitic load, and attachment preferences of the mites suggested their positive role in biological control of adult mosquitoes. The present study will set the path of future studies on host-parasite relationships of mites and mosquitoes and define the role of parasitic mites in the biological control of mosquitoes.

  5. [SUVA (Swiss Accident Insurance Fund) and silicosis. Silicosis in Switzerland. Development of technological dust control].

    Science.gov (United States)

    Bachofen, G

    1983-01-01

    In Switzerland the technical measures against quartz dust started in 1948 when wet drilling was compulsoryly introduced, initially in underground mining. The miners using the first wet drilling machines had serious problems with water, and only with the introduction of carriage drilling machines in 1963 did the method fully break through. Dust caused by blasting operations and by loading of the resultant material was limited by ventilation and sprinkling of water. In 1966 the first full-face cutting machines were used, and it was necessary to install a dust chamber behind the drill from which dust could be taken to a dust arrester. The problem of dust limitation when using boom cutters at sectional areas of more than 20 sq. meters without a pilot tunnel has not been resolved. Since 1970, dust in quarries and stone-cutter workshops has been successfully combated by the use of exhaust pumps in combination with filters. The use of quartz sand to clean metal pieces (sandblast) was forbidden in 1960. Today, materials of the same value, but quartz-free, are available. In foundries, dust production can be limited by continuous automation and installation of exhaust pumps in moulding units. For more than 30 years now the technical equipment has been available for successful prevention of quartz dust emissions. However, at some plants it is still difficult to persuade the personnel to use the protective equipment.

  6. Desiccant dust and the use of CO2 gas as a mobility stimulant for bed bugs: a potential control solution?

    Science.gov (United States)

    Aak, Anders; Roligheten, Espen; Rukke, Bjørn Arne; Birkemoe, Tone

    2017-01-01

    The common bed bug (Cimex lectularius, Hemiptera; Cimicidae) infests homes and service industries, and the number of infestations has greatly increased over the past 20 years. At present, no cost-effective control methods are available, and eradication programs are expensive and laborious. We investigated the control potential of desiccant dust in combination with CO2 as a bed bug activity stimulant. An initial experiment with two desiccant dusts was followed by arena studies with varying doses, available hiding places and the presence or absence of host signals. Finally, we conducted a field experiment with Syloid 244FP with or without CO2 gas. Syloid was superior compared to diatomaceous earth, and effective at the concentration of 1.0 g/m(2) in the field experiment. The number of harborages and partial application of desiccant dust decreased mortality in the laboratory. Bed bug activation by CO2 appeared of minor importance in the arena studies, but was crucial for the eradication in the student dormitories. In fact, all 5 bed bug-infested dormitories with a combined treatment of desiccant dust and CO2 were freed of bed bugs, whereas eradication was not successful in any of the 6 dormitories with only desiccant dust treatment. The different results in the laboratory and field experiment were most likely caused by the longer activation and higher dose of CO2 used in the field experiment than the laboratory experiment. Our study showed that application of desiccant dust in combination with release of CO2 gas to mimic human presence is a promising option for bed bug control.

  7. Nutrient control of N2 fixation in the oligotrophic Mediterranean Sea and the impact of Saharan dust events

    Directory of Open Access Journals (Sweden)

    M. Pujo-Pay

    2011-09-01

    Full Text Available A better understanding of the factors controlling N2 fixation is a pre-requisite for improving our knowledge on the contribution of N2 fixation process in the nitrogen cycling. Trace-metal clean nutrient/dust addition bioassays (+P, +PFe, +dust were performed at three stations located in the western, central and eastern Mediterranean Sea, in summer 2008 as part of the BOUM cruise. The main goals were (1 to investigate the nutrient factor(s limiting N2 fixation (uptake of 15N2 and (2 to evaluate the potential impact of a Saharan dust event on this biological process during the stratification period. Initially, surface waters at the three stations were DIP-depleted (2 fixation (from 130 % to 430 %. The highest dust stimulation of N2 fixation was recorded at the station located in the eastern basin. The response of diazotrophic activity to nutrient additions was variable between the sampled stations suggesting a spatial variability of the factor controlling N2 fixation over the whole basin. At all stations, N2 fixation was not limited by Fe nor co-limited by P and Fe. At the western station, N2 fixation was DIP limited while at the eastern one, N2 fixation was first DIP limited, then was limited by one or several chemical element(s released by dust. Our results demonstrated that a Saharan dust input was able to relieve these successive on going limitations. Very interestingly, at the station located in the central basin, N2 fixation was not limited by the availability of P yet it was strongly stimulated by dust addition (x3.1. A chemical element or a combination of several, released by the added dust may have been responsible for the observed stimulations of N2 fixation. These results indicated that Saharan dust pulses to the surface Mediterranean waters, in addition to P and Fe, could be a source of chemical(s element(s that are necessary for metabolic processes and therefore influence rates of N2 fixation.

  8. Domestic allergens in public places. II: Dog (Can f1) and cockroach (Bla g 2) allergens in dust and mite, cat, dog and cockroach allergens in the air in public buildings.

    Science.gov (United States)

    Custovic, A; Green, R; Taggart, S C; Smith, A; Pickering, C A; Chapman, M D; Woodcock, A

    1996-11-01

    Sensitization and exposure to indoor allergens are the major risk factors for asthma. It is possible that significant exposure to domestic allergens occurs outside the home. To investigate the levels of Can f 1 and Bla g 2 in the dust from carpeted floors and upholstered seats in public buildings and public transport and the airborne concentrations of Der p 1, Fel d 1, Can f 1 and Bla g 2 in schools and offices. Can f 1 and Bla g 2 were measured in the dust collected by vacuuming a 1 m2 area of carpet, as well as upholstered seats in five schools, six hotels, four cinemas, six pubs, three buses and two trains. Dust was also collected from the bedroom carpet, living room carpet, mattress and sofa in 20 homes with and 20 homes without a dog in the same area. Personal airborne sampling (2 L/min) was conducted for 8 h in offices (n = 16) and classrooms (n = 9). In addition, airborne samples in schools were collected using a high volume pump (60 L/min) for 1 h in three classrooms immediately after the children vacated the school. Can f 1, Bla g 2, Der p 1 and Fel d 1 were assayed using a two-site monoclonal antibody-based ELISA. Can f 1 was detected in all dust samples from public places, ranging from 0.2 to 52.5 micrograms/g. Significantly higher levels were found in upholstered seats (geometric mean--GM 9.4 micrograms/g) than in carpets (GM 1.5 micrograms/g; P 10 micrograms/g were found in 40% of upholstered seats in public places. Can f 1 was significantly higher in upholstered seats in public places than in sofas in homes without a dog (GM 1.8 micrograms/g; P < 0.001). Detectable levels of Bla g 2 were found in all of the schools (GM 2.4 U/g, range 0.8-4.4 U/g). Bla g 2 concentration greater than 2U/g (provisional threshold level representing risk of sensitization) was measured in 65% of the classrooms sampled. Der p 1 and Bla g 2 were below the detection limit in all airborne samples. However, airborne Fel d 1 and Can f 1 were detected in schools and offices

  9. Respirable dust measured downwind during rock dust application.

    Science.gov (United States)

    Harris, M L; Organiscak, J; Klima, S; Perera, I E

    2017-05-01

    The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) conducted underground evaluations in an attempt to quantify respirable rock dust generation when using untreated rock dust and rock dust treated with an anticaking additive. Using personal dust monitors, these evaluations measured respirable rock dust levels arising from a flinger-type application of rock dust on rib and roof surfaces. Rock dust with a majority of the respirable component removed was also applied in NIOSH's Bruceton Experimental Mine using a bantam duster. The respirable dust measurements obtained downwind from both of these tests are presented and discussed. This testing did not measure miners' exposure to respirable coal mine dust under acceptable mining practices, but indicates the need for effective continuous administrative controls to be exercised when rock dusting to minimize the measured amount of rock dust in the sampling device.

  10. Composition of dust deposited to snow cover in the Wasatch Range (Utah, USA): Controls on radiative properties of snow cover and comparison to some dust-source sediments

    Science.gov (United States)

    Reynolds, Richard L.; Goldstein, Harland L.; Moskowitz, Bruce M.; Bryant, Ann C.; Skiles, S. McKenzie; Kokaly, Raymond F.; Flagg, Cody B.; Yauk, Kimberly; Berquó, Thelma S.; Breit, George N.; Ketterer, Michael; Fernandez, Daniel; Miller, Mark E.; Painter, Thomas H.

    2014-01-01

    Dust layers deposited to snow cover of the Wasatch Range (northern Utah) in 2009 and 2010 provide rare samples to determine the relations between their compositions and radiative properties. These studies are required to comprehend and model how such dust-on-snow (DOS) layers affect rates of snow melt through changes in the albedo of snow surfaces. We evaluated several constituents as potential contributors to the absorption of solar radiation indicated by values of absolute reflectance determined from bi-conical reflectance spectroscopy. Ferric oxide minerals and carbonaceous matter appear to be the primary influences on lowering snow-cover albedo. Techniques of reflectance and Mössbauer spectroscopy as well as rock magnetism provide information about the types, amounts, and grain sizes of ferric oxide minerals. Relatively high amounts of ferric oxide, indicated by hard isothermal remanent magnetization (HIRM), are associated with relatively low average reflectance (hematite and goethite, representing about 35% of the total Fe-bearing phases. Nevertheless, goethite (α-FeOOH) is the dominant ferric oxide found by reflectance spectroscopy and thus appears to be the main iron oxide control on absorption of solar radiation. At least some goethite occurs as nano-phase grain coatings less than about 50 nm thick. Relatively high amounts of organic carbon, indicating as much as about 10% organic matter, are also associated with lower reflectance values. The organic matter, although not fully characterized by type, correlates strongly with metals (e.g., Cu, Pb, As, Cd, Mo, Zn) derived from distal urban and industrial settings, probably including mining and smelting sites. This relation suggests anthropogenic sources for at least some of the carbonaceous matter, such as emissions from transportation and industrial activities. The composition of the DOS samples can be compared with sediments in a likely dust-source setting at the Milford Flat Fire (MFF) area about 225

  11. Composition of dust deposited to snow cover in the Wasatch Range (Utah, USA): Controls on radiative properties of snow cover and comparison to some dust-source sediments

    Science.gov (United States)

    Reynolds, Richard L.; Goldstein, Harland L.; Moskowitz, Bruce M.; Bryant, Ann C.; Skiles, S. McKenzie; Kokaly, Raymond F.; Flagg, Cody B.; Yauk, Kimberly; Berquó, Thelma; Breit, George; Ketterer, Michael; Fernandez, Daniel; Miller, Mark E.; Painter, Thomas H.

    2014-12-01

    Dust layers deposited to snow cover of the Wasatch Range (northern Utah) in 2009 and 2010 provide rare samples to determine the relations between their compositions and radiative properties. These studies are required to comprehend and model how such dust-on-snow (DOS) layers affect rates of snow melt through changes in the albedo of snow surfaces. We evaluated several constituents as potential contributors to the absorption of solar radiation indicated by values of absolute reflectance determined from bi-conical reflectance spectroscopy. Ferric oxide minerals and carbonaceous matter appear to be the primary influences on lowering snow-cover albedo. Techniques of reflectance and Mössbauer spectroscopy as well as rock magnetism provide information about the types, amounts, and grain sizes of ferric oxide minerals. Relatively high amounts of ferric oxide, indicated by hard isothermal remanent magnetization (HIRM), are associated with relatively low average reflectance (iron oxide control on absorption of solar radiation. At least some goethite occurs as nano-phase grain coatings less than about 50 nm thick. Relatively high amounts of organic carbon, indicating as much as about 10% organic matter, are also associated with lower reflectance values. The organic matter, although not fully characterized by type, correlates strongly with metals (e.g., Cu, Pb, As, Cd, Mo, Zn) derived from distal urban and industrial settings, probably including mining and smelting sites. This relation suggests anthropogenic sources for at least some of the carbonaceous matter, such as emissions from transportation and industrial activities. The composition of the DOS samples can be compared with sediments in a likely dust-source setting at the Milford Flat Fire (MFF) area about 225 km southwest of Salt Lake City. The MFF area represents geologically and physiographically similar and widespread dust sources west-southwest of the Wasatch Range and heavily populated Wasatch Front. The DOS

  12. Environmental Engineering Approaches toward Sustainable Management of Spider Mites.

    Science.gov (United States)

    Suzuki, Takeshi

    2012-10-26

    Integrated pest management (IPM), which combines physical, biological, and chemical control measures to complementary effect, is one of the most important approaches to environmentally friendly sustainable agriculture. To expand IPM, we need to develop new pest control measures, reinforce existing measures, and investigate interactions between measures. Continued progress in the development of environmental control technologies and consequent price drops have facilitated their integration into plant production and pest control. Here I describe environmental control technologies for the IPM of spider mites through: (1) the disturbance of photoperiod-dependent diapause by artificial light, which may lead to death in seasonal environments; (2) the use of ultraviolet radiation to kill or repel mites; and (3) the use of water vapor control for the long-term cold storage of commercially available natural enemies. Such environmental control technologies have great potential for the efficient control of spider mites through direct physical effects and indirect effects via natural enemies.

  13. Environmental Engineering Approaches toward Sustainable Management of Spider Mites

    Directory of Open Access Journals (Sweden)

    Takeshi Suzuki

    2012-10-01

    Full Text Available Integrated pest management (IPM, which combines physical, biological, and chemical control measures to complementary effect, is one of the most important approaches to environmentally friendly sustainable agriculture. To expand IPM, we need to develop new pest control measures, reinforce existing measures, and investigate interactions between measures. Continued progress in the development of environmental control technologies and consequent price drops have facilitated their integration into plant production and pest control. Here I describe environmental control technologies for the IPM of spider mites through: (1 the disturbance of photoperiod-dependent diapause by artificial light, which may lead to death in seasonal environments; (2 the use of ultraviolet radiation to kill or repel mites; and (3 the use of water vapor control for the long-term cold storage of commercially available natural enemies. Such environmental control technologies have great potential for the efficient control of spider mites through direct physical effects and indirect effects via natural enemies.

  14. Predatory mite fauna in Aegean vineyards

    OpenAIRE

    GÖVEN, Mehmet Ali; ÇOBANOĞLU, Sultan; GÜVEN, Bilgin

    2010-01-01

    This study was carried out between 1997-2004 in vineyard areas in Manisa, İzmir, Denizli, Muğla and Çanakkale (Bozcaada) provinces of the Aegean region to determine biological control possibilities against phytophagous mites. Sampling was conducted from May to October. Most of the vineyards were sampled three times during the growing season and 50 leaves were collected randomly in each vineyard. Colomerus vitis (Pagenstecher) and Calepitrimerus vitis (Nalepa)were determined ...

  15. Quantitative PCR-based genome size estimation of the astigmatid mites Sarcoptes scabiei, Psoroptes ovis and Dermatophagoides pteronyssinus

    Directory of Open Access Journals (Sweden)

    Mounsey Kate E

    2012-01-01

    Full Text Available Abstract Background The lack of genomic data available for mites limits our understanding of their biology. Evolving high-throughput sequencing technologies promise to deliver rapid advances in this area, however, estimates of genome size are initially required to ensure sufficient coverage. Methods Quantitative real-time PCR was used to estimate the genome sizes of the burrowing ectoparasitic mite Sarcoptes scabiei, the non-burrowing ectoparasitic mite Psoroptes ovis, and the free-living house dust mite Dermatophagoides pteronyssinus. Additionally, the chromosome number of S. scabiei was determined by chromosomal spreads of embryonic cells derived from single eggs. Results S. scabiei cells were shown to contain 17 or 18 small (S. scabiei and P. ovis were 96 (± 7 Mb and 86 (± 2 Mb respectively, among the smallest arthropod genomes reported to date. The D. pteronyssinus genome was estimated to be larger than its parasitic counterparts, at 151 Mb in female mites and 218 Mb in male mites. Conclusions This data provides a starting point for understanding the genetic organisation and evolution of these astigmatid mites, informing future sequencing projects. A comparitive genomic approach including these three closely related mites is likely to reveal key insights on mite biology, parasitic adaptations and immune evasion.

  16. Effectiveness of dust control methods for crystalline silica and respirable suspended particulate matter exposure during manual concrete surface grinding.

    Science.gov (United States)

    Akbar-Khanzadeh, Farhang; Milz, Sheryl A; Wagner, Cynthia D; Bisesi, Michael S; Ames, April L; Khuder, Sadik; Susi, Pam; Akbar-Khanzadeh, Mahboubeh

    2010-12-01

    Concrete grinding exposes workers to unacceptable levels of crystalline silica dust, known to cause diseases such as silicosis and possibly lung cancer. This study examined the influence of major factors of exposure and effectiveness of existing dust control methods by simulating field concrete grinding in an enclosed workplace laboratory. Air was monitored during 201 concrete grinding sessions while using a variety of grinders, accessories, and existing dust control methods, including general ventilation (GV), local exhaust ventilation (LEV), and wet grinding. Task-specific geometric mean (GM) of respirable crystalline silica dust concentrations (mg/m³ for LEV:HEPA-, LEV:Shop-vac-, wet-, and uncontrolled-grinding, while GV was off/on, were 0.17/0.09, 0.57/0.13, 1.11/0.44, and 23.1/6.80, respectively. Silica dust concentrations (mg/m³ using 100-125 mm (4-5 inch) and 180 mm (7 inch) grinding cups were 0.53/0.22 and 2.43/0.56, respectively. GM concentrations of silica dust were significantly lower for (1) GV on (66.0%) vs. off, and (2) LEV:HEPA- (99.0%), LEV:Shop-vac- (98.1%) or wet- (94.4%) vs. uncontrolled-grinding. Task-specific GM of respirable suspended particulate matter (RSP) concentrations (mg/m³ for LEV:HEPA-, LEV:Shop-vac-, wet-, and uncontrolled grinding, while GV was off/on, were 1.58/0.63, 7.20/1.15, 9.52/4.13, and 152/47.8, respectively. GM concentrations of RSP using 100-125 mm and 180 mm grinding cups were 4.78/1.62 and 22.2/5.06, respectively. GM concentrations of RSP were significantly lower for (1) GV on (70.2%) vs. off, and (2) LEV:HEPA- (98.9%), LEV:Shop-vac- (96.9%) or wet- (92.6%) vs. uncontrolled grinding. Silica dust and RSP were not significantly affected by (1) orientation of grinding surfaces (vertical vs. inclined); (2) water flow rates for wet grinding; (3) length of task-specific sampling time; or, (4) among cup sizes of 100, 115 or 125 mm. No combination of factors or control methods reduced an 8-hr exposure level to below the

  17. Generation, analysis and functional annotation of expressed sequence tags from the ectoparasitic mite Psoroptes ovis

    Directory of Open Access Journals (Sweden)

    Kenyon Fiona

    2011-07-01

    Full Text Available Abstract Background Sheep scab is caused by Psoroptes ovis and is arguably the most important ectoparasitic disease affecting sheep in the UK. The disease is highly contagious and causes and considerable pruritis and irritation and is therefore a major welfare concern. Current methods of treatment are unsustainable and in order to elucidate novel methods of disease control a more comprehensive understanding of the parasite is required. To date, no full genomic DNA sequence or large scale transcript datasets are available and prior to this study only 484 P. ovis expressed sequence tags (ESTs were accessible in public databases. Results In order to further expand upon the transcriptomic coverage of P. ovis thus facilitating novel insights into the mite biology we undertook a larger scale EST approach, incorporating newly generated and previously described P. ovis transcript data and representing the largest collection of P. ovis ESTs to date. We sequenced 1,574 ESTs and assembled these along with 484 previously generated P. ovis ESTs, which resulted in the identification of 1,545 unique P. ovis sequences. BLASTX searches identified 961 ESTs with significant hits (E-value P. ovis ESTs. Gene Ontology (GO analysis allowed the functional annotation of 880 ESTs and included predictions of signal peptide and transmembrane domains; allowing the identification of potential P. ovis excreted/secreted factors, and mapping of metabolic pathways. Conclusions This dataset currently represents the largest collection of P. ovis ESTs, all of which are publicly available in the GenBank EST database (dbEST (accession numbers FR748230 - FR749648. Functional analysis of this dataset identified important homologues, including house dust mite allergens and tick salivary factors. These findings offer new insights into the underlying biology of P. ovis, facilitating further investigations into mite biology and the identification of novel methods of intervention.

  18. Morphological, molecular and cross-breeding analysis of geographic populations of coconut-mite associated predatory mites identified as Neoseiulus baraki: evidence for cryptic species?

    NARCIS (Netherlands)

    N.F. Sourassou; R. Hanna; I. Zannou; J.A.J. Breeuwer; G. de Moraes; M.W. Sabelis

    2012-01-01

    Surveys were conducted in Brazil, Benin and Tanzania to collect predatory mites as candidates for control of the coconut mite Aceria guerreronis Keifer, a serious pest of coconut fruits. At all locations surveyed, one of the most dominant predators on infested coconut fruits was identified as Neosei

  19. Ocean dynamics, not dust, have controlled equatorial Pacific productivity over the past 500,000 years

    Science.gov (United States)

    Winckler, Gisela; Anderson, Robert F.; Jaccard, Samuel L.; Marcantonio, Franco

    2016-05-01

    Biological productivity in the equatorial Pacific is relatively high compared with other low-latitude regimes, especially east of the dateline, where divergence driven by the trade winds brings nutrient-rich waters of the Equatorial Undercurrent to the surface. The equatorial Pacific is one of the three principal high-nutrient low-chlorophyll ocean regimes where biological utilization of nitrate and phosphate is limited, in part, by the availability of iron. Throughout most of the equatorial Pacific, upwelling of water from the Equatorial Undercurrent supplies far more dissolved iron than is delivered by dust, by as much as two orders of magnitude. Nevertheless, recent studies have inferred that the greater supply of dust during ice ages stimulated greater utilization of nutrients within the region of upwelling on the equator, thereby contributing to the sequestration of carbon in the ocean interior. Here we present proxy records for dust and for biological productivity over the past 500 ky at three sites spanning the breadth of the equatorial Pacific Ocean to test the dust fertilization hypothesis. Dust supply peaked under glacial conditions, consistent with previous studies, whereas proxies of export production exhibit maxima during ice age terminations. Temporal decoupling between dust supply and biological productivity indicates that other factors, likely involving ocean dynamics, played a greater role than dust in regulating equatorial Pacific productivity.

  20. 485 Therapeutic Effect and Safety of Tropical Mite Allergen Vaccines by Subcutaneous Route in Allergic Asthmatics Patients

    Science.gov (United States)

    Castro Almarales, Raúl Lázaro; Ronquillo, Mercedes; Castello, Mirta Alvarez; Rodríguez, José; González, Mayda; Labrada, Alexis; Navarro Viltres, Bárbara I; Díaz, Yunia Oliva; Mateo, Maytee

    2012-01-01

    Background Allergen-specific subcutaneous immunotherapy (SCIT) is presently recognized as a biological response modifier, as it is the only available treatment able to influence the natural course of allergic disease. Extensive clinical evidence supports its efficacy. Safety concerns are related to the risks of anaphylactic reactions during treatment. Standardization of allergen vaccines in terms of allergenic activity allows a more precise control over the administered doses and can be, therefore, very relevant for both efficacy and safety of SCIT. House Dust Mites (HDM), particularly Dermatophagoides pteronyssinus (Dp), Dermatophagoides siboney (Ds) and Blomia tropicalis (Bt) have been described as very relevant allergen sources in Cuba, with a strong association to respiratory allergy symptoms. Objective To asses the efficacy and safety of standardized allergen vaccines of these 3 mite species (Valergen, Biocen, Cuba) in Cuban asthmatic patients. Methods Three Double-Blind Placebo-Controlled clinical trials were performed in 40 patients each, showing asthmatic symptoms and positive predominant Skin Prick Test (SPT) to each mite, respectively. Half of patients received the active treatment consisting of subcutaneous injections with increasing doses, up to 6000 BU. Results The total 1 year cumulative dose was 63035 BU, in an average of 20.5 injections. The treatment was effective in the reduction of clinical symptoms (up to 32%, 95%CI: 28-36%; P = 0.0006) and medication intake (23%, 95%CI:18-28%), as compared to control treatment. The skin sensitivity to the allergens decreased significantly (P = 0.0001), with regard to the beginning of the treatment. The allergen amount needed to induce a positive SPT increased 297-fold. An improvement of the lung function was observed, expressed in a modest Peak-Expiratory-Flow increase (P < 0.05) and reduction of PEF daily variability. SIT was considered effective in 71% of patients. The frequency of local adverse reactions was

  1. Towards integrated control of varroa: effect of variation in hygienic behaviour among honey bee colonies on mite population increase and deformed wing virus incidence

    OpenAIRE

    Al Toufailia, Hasan M; Amiri, Esmaeil; Scandian, Luciano; Kryger, Per; Ratnieks, Francis L. W.

    2014-01-01

    Hygienic behaviour in the honey bee, Apis mellifera, is the uncapping and removal of dead, diseased or infected brood from sealed cells by worker bees. We determined the effect of hygienic behaviour on varroa population growth and incidence of deformed wing virus (DWV), which can be transmitted by varroa. We treated 42 broodless honey bee colonies with oxalic acid in early January 2013 to reduce varroa populations to low levels, which we quantified by extracting mites from a sample of worker ...

  2. The role of volatiles in aggregation and host-seeking of the haematophagous poultry red mite Dermanyssus gallinae (Acari: Dermanyssidae).

    Science.gov (United States)

    Koenraadt, C J M; Dicke, M

    2010-03-01

    Infestations with ectoparasitic poultry red mites (Dermanyssus gallinae) pose an increasing threat to poultry health and welfare. Because of resistance to acaricides and higher scrutiny of poultry products, alternative and environmentally safe management strategies are warranted. Therefore, we investigated how volatile cues shape the behavior of D. gallinae and how this knowledge may be exploited in the development of an attract-and-kill method to control mite populations. A Y-tube olfactometer bio-assay was used to evaluate choices of mites in response to cues related to conspecific mites as well as related to their chicken host. Both recently fed and starved mites showed a strong preference (84 and 85%, respectively) for volatiles from conspecific, fed mites as compared to a control stream of clean air. Mites were also significantly attracted to 'aged feathers' (that had remained in the litter for 3-4 days), but not to 'fresh feathers'. Interestingly, an air stream containing 2.5% CO(2), which mimics the natural concentration in air exhaled by chickens, did attract fed mites, but inhibited the attraction of unfed mites towards volatiles from aged feathers. We conclude that both mite-related cues (aggregation pheromones) and host-related cues (kairomones) mediate the behavior of the poultry mite. We discuss the options to exploit this knowledge as the 'attract' component of attract-and-kill strategies for the control of D. gallinae.

  3. PCR analysis for Wolbachia in human and canine Demodex mites.

    Science.gov (United States)

    Borgo, Sibylle N; Sattler, Elke C; Hogardt, Michael; Adler, Kristin; Plewig, Gerd

    2009-10-01

    In many skin diseases such as Demodex folliculitis, rosacea- or steroid-induced rosacea Demodex mites are present in abundance and are at least partially held responsible for causing these disorders. Although it is known that these diseases respond well to tetracyclines, it is unclear if this is due to the antiinflammatory effects of the antibiotics or to an antibacterial effect on so far unknown bacteria within the Demodex mites. As in filariasis, where the response to doxycycline can be explained by the presence of Wolbachia within the filarial nematodes, this study was performed to see whether Wolbachia also use Demodex mites as their hosts. Human and canine Demodex mite samples were taken by skin scrapings and tested by PCR for the presence of Wolbachia DNA. Wolbachia pipientis DNA was used as positive control. In none of the DNA extracts, Wolbachia were detected showing no evidence for the presence of these bacteria in Demodex mites. The response of Demodex aggravated or Demodex caused diseases to tetracyclines seems not to be due to the presence of Wolbachia in Demodex mites in contrast to the results seen in filariasis.

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

    Science.gov (United States)

    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 0.05). However,the IFN-γ level in BALF was lower compared with the negative control and PBS 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 allergic disorders in this area.

  5. Diversity and significance of eriophyoid mites (Acari: Eriophyoidea associated with coniferous trees in Poland: a review

    Directory of Open Access Journals (Sweden)

    Kiedrowicz Agnieszka

    2016-06-01

    Full Text Available Among the approximately 200 eriophyoid mite species associated with coniferous trees worldwide, 33 species (of the families Eriophyidae and Phytoptidae infest conifers in Poland, and 24 of them can cause visible feeding symptoms. In this paper we discuss the importance of eriophyoid mites to coniferous plants in Poland and their potential impact on the decorative value of ornamental plants. We emphasize the general lack of knowledge about the diversity of eriophyoid mites associated with coniferous trees and its role in the management and control of this economically important mite group.

  6. 不同方法提取粉尘螨变应原致敏效果的优化研究%Comparison of the sensitizing effect of crude extracts of house dust mites obtained using 4 types of extraction solutions

    Institute of Scientific and Technical Information of China (English)

    郭伟; 刘志明; 姜玉新; 李朝品

    2012-01-01

    目的 比较常用4种提取液提取的粉尘螨变应原致敏效果. 方法 分别用磷酸盐缓冲液(PBS,pH7.2)、PBST(含0.05%Tween 20的PBS)、Coca's液、0.125 mol/L NH4HCO3按料液比1∶20(W/V)的比例提取粉尘螨变应原并进行12.5% SDS-PAGE电泳,Bradford法检测提取物蛋白浓度,Western blot检测抗原性.以上述各组提取液分别致敏BALB/c小鼠,制备哮喘模型(分为PBS组,PBST组,Coca's液、NH4HCO3组,PBS阴性组,OVA组).采集小鼠血和支气管肺泡灌洗液(BALF),ELISA法检测血清IgE和BALF中的IFN-γ、IL-4水平,对BALF中嗜酸性粒细胞数进行统计分析.制备肺组织病理切片,观察病理变化. 结果 与其他各组相比,Coca's液提取变应原蛋白浓度最高[(274±23.6)μg/ml](P<0.05);SDS PAGE电泳检测各组提取蛋白分子质量单位均在35 ku~14 ku之间.ELISA检测Coca,s液组血清IgE含量显著高于其他组(OVA组除外)(P<0.05);BALF中IFN-γ、IL-4含量Coca’s液组与PBS阴性组、PBS组、PBST组和NH4HCO3组比较差异有统计学意义(P<0.05). 结论 在4种提取液中,以Coca's液提取的粉尘螨变应原致敏效果最佳.%Objective To compare the sensitizing effect of crude extracts of house dust mites obtained using 4 types of extraction solutions. Methods Crude extracts were obtained at a ratio of material: solution of 1 : 20 (W/V) using phosphate-buffered saline (PBS, pH7. 2), PBST (0. 05% Tween-20 in PBS), Coca's solution, and 0. 125 mol/L NH4 HCO3 solution. The crude extracts were tested with SDS-PAGE electrophoresis, detected using the Bradford method, and confirmed using Western blotting. Murine asthmatic models were prepared using the crude extracts mentioned as an allergen; mice were divided into a PBS-negative group, PBS group, PBST group, Coca's solution group, and NH, HCO3 group. Sera and bronchoalveolar lavage fluid (BALF) were collected from animals. The level of IgE in serum was detected with ELISA, and levels of IFN-γ and IL-4

  7. Eficacia del Oxavar® para el Control del Ácaro Varroa destructor (Varroidae en Colmenas de Apis mellifera (Apidae Efficacy of Oxavar® to control the mite Varroa destructor (Varroidae in honeybee colonies of Apis mellifera (Apidae

    Directory of Open Access Journals (Sweden)

    Jorge Augusto Marcangeli

    2003-12-01

    Full Text Available El objetivo del trabajo fue evaluar la eficacia del producto Oxavar® para el control del ácaro Varroa destructor (Anderson & Trueman en colmenas de abejas Apis mellifera durante la primavera de 2002 y otoño de 2003. El trabajo se llevó a cabo en el apiario experimental del Centro de Extensión Apícola ubicado en Coronel Vidal, provincia de Buenos Aires. Se trabajó sobre un total de 20 colmenas tipo Langstroth que se dividieron en dos grupos iguales. El primer grupo recibió 5 ml de Oxavar® (323 g en 5000 ml de agua destilada por cuadro cubierto por abejas. El segundo grupo, el testigo, recibió 5 ml de agua destilada por cuadro cubierto por abejas. Ambos grupos recibieron tres dosis a intervalos de siete días. Semanalmente, se recolectaron los ácaros muertos caídos en pisos especiales que evitaban que las abejas los eliminen. Posteriormente, en los dos grupos se colocaron tiras del producto Apistan® para eliminar los ácaros remanentes en las colonias y poder así calcular la eficacia del tratamiento. El producto Oxavar® presentó una eficacia promedio de 85,5 % ± 2,8 durante la primavera y 86,1% ± 2,6 durante el otoño, no mostrando diferencias significativas entre las estaciones (p> 0,05. En ambos casos se registraron diferencias significativas frente al grupo control (pThe aim of this work was to evaluate the acaricide efficacy of Oxavar® to control Varroa destructor (Anderson & Trueman in Apis mellifera (L colonies during the spring 2002 and the autumn 2003. Work was done at “Centro de Extensión Apícola” experimental apiary located in Coronel Vidal, province of Buenos Aires. Twenty Langstroth hives were used divided in two equal groups. The first group received 5 ml of Oxavar® (323 g in 5000 ml of destiled water per comb covered by honeybees and the second one received 5 ml of destiled water. Both groups received three dosages at seven day periods. Dead mites were collected weekly from special floors in order to avoid

  8. "Back fall" dust controls seasonal erosion and composition measurements of 67P

    Science.gov (United States)

    Keller, Horst Uwe; Hviid, Stubbe F.; Mottola, Stefano; Agarwal, Jessica; OSIRIS

    2016-10-01

    Seasonal effects of 67P's activity are very pronounced due to the strong insolation during southern summer when the comet is near its perihelion. About ¾ of the overall gas and dust production are released from the southern hemisphere when large parts of the surface near the north pole are in polar night (Keller et al. 2015). This leads to a dichotomy of the hemispheres. The southern regions show rough consolidated material whereas the northern plain surfaces are covered by what looks like dust (El Maary et al 2015). Recent close up observations of the northern territories show a granularity near the resolution limit of the images. This is comparable to the sizes of particles (10-20 cm) seen to cross the coma at velocities comparable to or below the escape speed from the nucleus around perihelion. These large particles are deprived from super volatiles but maintain their water ice content. A major part will cover the northern hemisphere as "back fall" over the aphelion passage and will lead to water controlled activity from the northern hemisphere during the next cometary approach. New dune-like features (Thomas et al. 2015) have been recently observed in the gravitational low Hapi region. Philae ROLIS images show wind tails and moats around obstacles, all oriented in a south-north direction, that are well modelled by abrasion by impinging back fall from the south (Mottola et al. 2015). Consequently activity from the northern hemisphere during the early Rosetta mission revealed mainly water molecules (Fougere et al. to be submitted) originating from back fall and not from the original consolidated surface, that was widely isolated by the cover of back fall. Hence more volatile compounds such as CO2 and CO are not reached by insolation. Composition measurements of the northern hemisphere are strongly influenced by the back fall cover and do not reflect the original composition of the nucleus. A further consequence is that erosion of the nucleus of 67P takes place

  9. Mineral dust aerosols over the Sahara: Meteorological controls on emission and transport and implications for modeling

    Science.gov (United States)

    Knippertz, Peter; Todd, Martin C.

    2012-02-01

    Atmospheric mineral dust has recently become an important research field in Earth system science because of its impacts on radiation, clouds, atmospheric dynamics and chemistry, air quality, and biogeochemical cycles. Studying and modeling dust emission and transport over the world's largest source region, the Sahara, is particularly challenging because of the complex meteorology and a very sparse observational network. Recent advances in satellite retrievals together with ground- and aircraft-based field campaigns have fostered our understanding of the spatiotemporal variability of the dust aerosol and its atmospheric drivers. We now have a more complete picture of the key processes in the atmosphere associated with dust emission. These cover a range of scales from (1) synoptic scale cyclones in the northern sector of the Sahara, harmattan surges and African easterly waves, through (2) low-level jets and cold pools of mesoscale convective systems (particularly over the Sahel), to (3) microscale dust devils and dusty plumes, each with its own pronounced diurnal and seasonal characteristics. This paper summarizes recent progress on monitoring and analyzing the dust distribution over the Sahara and discusses implications for numerical modeling. Among the key challenges for the future are a better quantification of the relative importance of single processes and a more realistic representation of the effects of the smaller-scale meteorological features in dust models. In particular, moist convection has been recognized as a major limitation to our understanding because of the inability of satellites to observe dust under clouds and the difficulties of numerical models to capture convective organization.

  10. The chemically controlled synthesis of dust in type II-P supernovae

    CERN Document Server

    Sarangi, Arkaprabha

    2013-01-01

    We study the formation of molecules and dust clusters in the ejecta of solar metallicity, Type II-P supernovae using a chemical kinetic approach. We follow the evolution of molecules and small dust cluster masses from day 100 to day 1500 after explosion. We consider stellar progenitors with initial mass of 12, 15, 19 and 25 Msun that explode as supernovae with stratified ejecta. The molecular precursors to dust grains comprise molecular chains, rings and small clusters of silica, silicates, metal oxides, sulphides and carbides, pure metals, and carbon, where the nucleation of silicate clusters is described by a two-step process of metal and oxygen addition. We study the impact of the 56Ni mass on the type and amount of synthesised dust. We predict that large masses of molecules including CO, SiO, SiS, O2, and SO form in the ejecta. We show that the discrepancy between the small dust masses detected at infrared wavelengths some 500 days post-explosion and the larger amounts of dust recently detected with Hersc...

  11. The Effect of Simulated Lunar Dust on the Absorptivity, Emissivity, and Operating Temperature on AZ-93 and Ag/FEP Thermal Control Surfaces

    Science.gov (United States)

    Gaier, James R.; Siamidis, John; Panko, Scott R.; Rogers, Kerry J.; Larkin, Elizabeth M. G.

    2008-01-01

    JSC-1AF lunar simulant has been applied to AZ-93 and AgFEP thermal control surfaces on aluminum or composite substrates in a simulated lunar environment. The temperature of these surfaces was monitored as they were heated with a solar simulator and cooled in a 30 K coldbox. Thermal modeling was used to determine the absorptivity ( ) and emissivity ( ) of the thermal control surfaces in both their clean and dusted states. Then, a known amount of power was applied to the samples while in the coldbox and the steady state temperatures measured. It was found that even a submonolayer of simulated lunar dust can significantly degrade the performance of both white paint and second-surface mirror type thermal control surfaces under these conditions. Contrary to earlier studies, dust was found to affect as well as . Dust lowered the emissivity by as much as 16 percent in the case of AZ-93, and raised it by as much as 11 percent in the case of AgFEP. The degradation of thermal control surface by dust as measured by / rose linearly regardless of the thermal control coating or substrate, and extrapolated to degradation by a factor 3 at full coverage by dust. Submonolayer coatings of dust were found to not significantly change the steady state temperature at which a shadowed thermal control surface will radiate.

  12. Mite communities (Acari: Mesostigmata) in young and mature coniferous forests after surface wildfire.

    Science.gov (United States)

    Kamczyc, Jacek; Urbanowski, Cezary; Pers-Kamczyc, Emilia

    2017-06-01

    Density, diversity and assemblage structure of Mesostigmata (cohorts Gamasina and Uropodina) were investigated in Scots pine forests differing in forest age (young: 9-40 years and mature: 83-101 years) in which wildfire occurred. This animal group belongs to the dominant acarine predators playing a crucial role in soil food webs and being important as biological control agents. In total, six forests (three within young and three within mature stands) were inspected in Puszcza Knyszyńska Forest Complex in May 2015. At each forest area, sampling was done from burned and adjacent control sites with steel cylinders for heat extraction of soil fauna. Data were analyzed statistically with nested ANOVA. We found a significant effect on mite density of both fire and forest age, with more mites in mature forests and control plots. In total, 36 mite taxa were identified. Mite diversity differed significantly between forest ages but not between burned versus control. Our study indicated that all studied forests are characterized by unique mite species and that the mite communities are dominated by different mite species depending on age forest and surface wildfire occurrence. Finally, canonical correspondence analysis ranked the mite assemblages from control mature, through burned young and burned mature, away from the control young.

  13. The Level of Mite Dermatophagoides’ Allergens (Der-p 1 and Der-f 1 in Birjand

    Directory of Open Access Journals (Sweden)

    Mohammad Fereidouni

    2014-06-01

    Full Text Available Background: House dust mite allergens especially pyroglyphid species are among the most important indoor allergens and have an important role in development of asthma and allergies. Materials and Methods: In current study, the level of two main allergens from mites including Der-p1 and Der-f 1 in dust of 28 homes in Birjand city was measured by ELISA method. Results: All samples were negative for Der-p1. Low leverl of Der-f 1 was detected in one sample. Prevalence of asthma, rhinitis and rhinoconjunctivitis was 2%, 28% and 15% respectively. Conclusion: The results of this study suggest that House dust mites could not grow in Birjand climate.

  14. Abundance, Genetic Diversity and Persistence of Metarhizium Spp. Fungi from Soil of Strawberry Crops and Their Potential as Biological Control Agents against the Two-Spotted Spider Mite Tetranychus urticae

    DEFF Research Database (Denmark)

    Castro, Thiago Rodriguesde

    The growing demand for strawberries has imposed challenges, especially regarding the control of pests. Many farmers report problems with reduced chemical control efficiency, probably due to selection of resistant populations of insects and mites. An alternative is the use of biological control...... using pathogenic fungi as a tool in integrated pest management. Metarhizium spp. (Hypocreales: Clavicipitaceae) are generalist entomopathogenic fungi with worldwide distribution and can cause diseases in a large number of hosts. Many studies on the development of Metarhizium as a biological control...... agent were performed, but this bulk of knowledge is in remarkable contrast to the lack of research on the fundamental ecology of Metarhizium in agroecosystems. This thesis aimed to evaluate the establishment, persistence and dispersal of these entomopathogenic fungi in strawberry crop soil...

  15. Climatic controls of the interannual to decadal variability in Saudi Arabian dust activity: Towards the development of a seasonal prediction tool

    Science.gov (United States)

    Yu, Y.; Notaro, M.; Liu, Z.; Alkolibi, F.; Fadda, E.; Bakhrjy, F.

    2013-12-01

    Atmospheric dust significantly influences the climate system, as well as human life in Saudi Arabia. Skillful seasonal prediction of dust activity with climatic variables will help prevent some negative social impacts of dust storms. Yet, the climatic regulators on Saudi Arabian dust activity remain largely unaddressed. Remote sensing and station observations show consistent seasonal cycles in Saudi Arabian dust activity, which peaks in spring and summer. The climatic controls on springtime and summertime Saudi Arabian dust activity during 1975-2010 are studied using observational and reanalysis data. Empirical Orthogonal Function (EOF) of the observed Saudi Arabian dust storm frequency shows a dominant homogeneous pattern across the country, which has distinct interannual and decadal variations, as revealed by the power spectrum. Regression and correlation analyses reveal that Saudi Arabian dust activity is largely tied to precipitation on the Arabian Peninsula in spring and northwesterly (Shamal) wind in summer. On the seasonal-interannual time scale, warm El Niño-Southern Oscillation (ENSO) phase (El Niño) in winter-to-spring inhibits spring dust activity by increasing the precipitation over the Rub'al Khali Desert, a major dust source region on the southern Arabian Peninsula; warm ENSO and warm Indian Ocean Basin Mode (IOBM) in winter-to-spring favor less summer dust activity by producing anomalously low sea-level pressure over eastern north Africa and Arabian Peninsula, which leads to the reduced Shamal wind speed. The decadal variation in dust activity is likely associated with the Atlantic Multidecadal Oscillation (AMO), which impacts Sahel rainfall and North African dust, and likely dust transport to Saudi Arabia. The Pacific Decadal Oscillation (PDO) and tropical Indian Ocean SST also have influence on the decadal variation in Saudi Arabian dust activity, by altering precipitation over the Arabian Peninsula and summer Shamal wind speed. Using eastern

  16. Randomized double-blind placebo-controlled trial of sublingual immunotherapy in children with house dust mite allergy in primary care : study design and recruitment

    NARCIS (Netherlands)

    de Bot, Cindy M. A.; Moed, Heleen; Berger, Marjolein Y.; Roder, Esther; de Groot, Hans; de Jongste, Johan C.; van Wijk, Roy Gerth; van der Wouden, Johannes C.

    2008-01-01

    Background: For respiratory allergic disorders in children, sublingual immunotherapy has been developed as an alternative to subcutaneous immunotherapy. Sublingual immunotherapy is more convenient, has a good safety profile and might be an attractive option for use in primary care. A randomized doub

  17. Randomized double-blind placebo-controlled trial of sublingual immunotherapy in children with house dust mite allergy in primary care: Study design and recruitment

    NARCIS (Netherlands)

    C.M.A. de Bot (Cindy); H. Moed (Heleen); M.Y. Berger (Marjolein); E. Röder (Esther); H. de Groot (Hans); J.C. de Jongste (Johan); R. Gerth van Wijk (Roy); J.C. van der Wouden (Hans)

    2008-01-01

    textabstractBackground. For respiratory allergic disorders in children, sublingual immunotherapy has been developed as an alternative to subcutaneous immunotherapy. Sublingual immunotherapy is more convenient, has a good safety profile and might be an attractive option for use in primary care. A ran

  18. Mange mites of sheep and goats in selected sites of Eastern Amhara region, Ethiopia.

    Science.gov (United States)

    Seid, Kibeb; Amare, Sisay; Tolossa, Yacob Hailu

    2016-03-01

    A cross sectional study of small ruminant mange mites was conducted from November 2011 to April 2012 on a total of 324 sheep and 680 goats, to determine the prevalence of mange mites in sheep and goats, identifying the major species of mite and to determine the potential risk factors significantly predicting the disease. The result showed an overall mange mite prevalence of 7.5 % (95 % CI 5.5-9.5) in goats and 1.2 % (95 % CI 0.5-1.9) in sheep. The mites identified were Sarcoptes and Demodex in goats and Sarcoptes and Psoroptes in sheep. The prevalence of mange mites was significantly higher in goats than in sheep (χ(2) = 16.636, P = 0.000). There was higher prevalence of mange mites in poor body condition than good body condition sheep and goats and the difference was statistically significant (χ(2) = 5.513, P = 0.019 in sheep and χ(2) = 141.85, P = 0.000 in goats). But age and sex of the host animals and agro climates were not statistically significant predictors of prevalence of mange mite. This study demonstrated that mange mites are among the major parasitic health problems of shoats in Eastern Amhara region that require urgent control intervention.

  19. Structural Mechanisms of Inactivation in Scabies Mite Serine Protease Paralogues

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Katja; Langendorf, Christopher G.; Irving, James A.; Reynolds, Simone; Willis, Charlene; Beckham, Simone; Law, Ruby H.P.; Yang, Sundy; Bashtannyk-Puhalovich, Tanya A.; McGowan, Sheena; Whisstock, James C.; Pike, Robert N.; Kemp, David J.; Buckle, Ashley M.; (Monash); (Queensland Inst. of Med. Rsrch.)

    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 catalytically 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.

  20. EFEITO DE ACARICIDAS NO CONTROLE DO MICROÁCARO Aculops lycopersici (Massee, 1937 NO TOMATEIRO ESTAQUEADO EFFECT OF ACARICIDES ON THE CONTROL OF RUSSET MITE Aculops lycopersici (Massee, 1937 IN TOMATO PLANTS

    Directory of Open Access Journals (Sweden)

    Larissa Leandro Pires

    2007-09-01

    mite (Aculops lycopersici in tomato plants. The work was conducted in Goiânia, Goiás, Brazil. The Santa Adélia Super cultivar was grown using a stake system, with one plant per hole, each plant with one stem, in double rows, and spacing of 1.0 m between rows. Treatments were: Spirodiclofen (240 SC, in dosages of 0.20, 0.25 and 0.30 L p.c.ha-1; Azocyclotin (500 SC, 0.50 L p.c.ha-1; Azocyclotin (250 PM, 1.00 kg p.c.ha-1 and Control. Doses were applied in one-week intervals, 82, 89 and 96 days after germination. A previous sampling of the number of acarids in the plots was made 79 days after germination. The efficiency of the products and doses was evaluated in four samplings, one, three, seven and ten days after the last acaricide application. Four leaves were collected at random from the two central lines of each plot (sixteen leaves/treatment. From each leaf, five leaves were detached to count the number of russet mites. The being tested products reduced the population of A. lycopersici. The dose of 0.3 liter p.c.ha-1 of Spirodiclofen was the most effective in controlling tomato russet mite, up to three days after the last application. Spirodiclofen can be used to control tomato russet mite as a substitute for Azocyclotin, which is usually recommended.

    KEY-WORDS: Lycopersicon esculentum; Eriophyidae; chemical control.

  1. Soil chemistry adjacent to roads treated with dust control products at Squaw Creek National Wildlife Refuge

    Science.gov (United States)

    Kunz, Bethany K.

    2016-01-01

    The health of soils along roadways is critical for maximizing habitat quality and minimizing negative ecological effects of roads. Adjacent to unpaved roads, soil chemistry may be altered by the deposition of dust, as well as by road treatment with dust suppressants or soil stabilizer products. If present in roadside soils, these product residues may be available to plants, terrestrial invertebrates, or small mammals. Unfortunately, very few studies have attempted to track the transport of dust suppressants after application. As part of a larger ongoing study on the environmental effects of dust suppressant products on roadside plants and animals, we sampled roadside soils at Squaw Creek National Wildlife Refuge (NWR). Replicated road sections at Squaw Creek NWR had been previously treated with two road products—calcium chloride-based durablend-C™ and synthetic iso-alkane EnviroKleen®. In order to quantify the effect of dust suppressant treatment on roadside soils, we took replicated composite soil samples one year after treatment at 1m and 4m from the road’s edge, and analyzed samples for a suite of soil chemistry variables (pH, conductivity, NO3-N, P, K, Ca, Mg, Na and S). We also assessed dust suppressant product residues in the soil. For durablend-C™, we used soil conductivity as an indicator. For EnviroKleen®, we developed a method for extraction and isolation, followed by analysis with gas chromatography/mass spectrometry to look for a specific EnviroKleen® signature. Surprisingly, soil conductivity was not elevated adjacent to road sections treated with durablend-C™, relative to other sections. EnviroKleen® was detectable at both 1m and 4m from treated sections at concentrations from 1 to 1500 mg/kg, and was non-detectable in soils adjacent to the untreated section. The most notable characteristic of soils across all treated and untreated sections at 1m was elevated calcium (up to 30,000 mg/kg), likely as a result of dust deposition from the

  2. DIVERSITY AND ABUNDANCE OF MITES IN A MANDARIN CITRUS ORCHARD IN WEST SUMATRA

    Directory of Open Access Journals (Sweden)

    Affandi Affandi

    2016-10-01

    Full Text Available Some of the most destructive pests in citrus orchards are spider mites. Monitoring prior applied pest control is a standard procedure for integrated pest management (IPM. The study aimed to survey and determine the distribution, abundance, and diversity of phytophagous, predatory, and detritivorous mites at different stages of development of arboreal plant parts, weeds and litter in the citrus orchard. A periodical sampling survey method was conducted on six growth stages of mandarin citrus, weeds and litter of the Indonesian Fruits Research Institute experimental field in Solok, West Sumatra in December 2003 to June 2004. All mites attached on each growth stage of citrus, weeds and litter were trapped and mounted on slide for identification purposes. Identification of the mites was conducted in the Acarology Laboratory, Department of Entomology, University of the Philippines at Los Banos in July-October 2004. The results showed that a very rich mite fauna of 130 species was found in the arboreal parts of citrus crops, weeds and litter below the canopy of the citrus orchard. Among the trophic groups, detritivorous mites were the most abundant, followed by the predators, phytophages, and those unknown feeding habit. Among the habitats, weeds harbored the most mite species followed by litter and arboreal parts of the citrus trees. The flush growth stage had the least diverse mite fauna with index diversity (H’ of 1.27, while the most diverse (H’ = 2.01 was found at fruit development phase II. Result of this research was useful in determining proper time for controlling phytophagous mites. Besides, the result also provides important information on potential predatory mites that can be used as biological control agents. Furthermore, the study implies the importance of maintaining cover crops of weeds and litter beneath the citrus trees as refuge and source of alternate prey for predators which suppressed populations of phytophagous mites.

  3. Abundance, Genetic Diversity and Persistence of Metarhizium Spp. Fungi from Soil of Strawberry Crops and Their Potential as Biological Control Agents against the Two-Spotted Spider Mite Tetranychus urticae

    DEFF Research Database (Denmark)

    Castro, Thiago Rodriguesde

    The growing demand for strawberries has imposed challenges, especially regarding the control of pests. Many farmers report problems with reduced chemical control efficiency, probably due to selection of resistant populations of insects and mites. An alternative is the use of biological control...... agent were performed, but this bulk of knowledge is in remarkable contrast to the lack of research on the fundamental ecology of Metarhizium in agroecosystems. This thesis aimed to evaluate the establishment, persistence and dispersal of these entomopathogenic fungi in strawberry crop soil...... in Inconfidentes, Minas Gerais, Brazil; and to study the diversity and abundance of species of Metarhizium isolated from organic and conventional strawberry crop soils, and from the field margins in Brazil and Denmark. The effectiveness of new species of Metarhizium recently found in Brazil, was evaluated against...

  4. The Level of Mite Dermatophagoides’ Allergens (Der-p 1 and Der-f 1) in Birjand

    OpenAIRE

    Mohammad Fereidouni; Farkhondeh Fereidouni; Mehrasa Hadian; Zahra Asghari; S. Masood Zojaji

    2014-01-01

    Background: House dust mite allergens especially pyroglyphid species are among the most important indoor allergens and have an important role in development of asthma and allergies. Materials and Methods: In current study, the level of two main allergens from mites including Der-p1 and Der-f 1 in dust of 28 homes in Birjand city was measured by ELISA method. Results: All samples were negative for Der-p1. Low leverl of Der-f 1 was detected in one sample. Prevalence of asthma, rhinitis an...

  5. Population growth of Varroa destructor (Acari: Varroidae) in colonies of Russian and unselected honey bee (Hymenoptera: Apidae) stock as related to numbers of foragers with mites

    Science.gov (United States)

    Varroa mites are an external parasite of honey bees and a leading cause of colony losses worldwide. Varroa populations can be controlled with miticides, but mite resistant stocks such as the Russian honey bee (RHB) also are available. RHB and other mite resistant stock limit Varroa population growth...

  6. The effect of antibiotics on associated bacterial community of stored product mites.

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    Jan Kopecky

    Full Text Available Bacteria are associated with the gut, fat bodies and reproductive organs of stored product mites (Acari: Astigmata. The mites are pests due to the production of allergens. Addition of antibiotics to diets can help to characterize the association between mites and bacteria.Ampicillin, neomycin and streptomycin were added to the diets of mites and the effects on mite population growth (Acarus siro, Lepidoglyphus destructor and Tyrophagus putrescentiae and associated bacterial community structure were assessed. Mites were treated by antibiotic supplementation (1 mg g(-1 of diet for 21 days and numbers of mites and bacterial communities were analyzed and compared to the untreated control. Bacterial quantities, determined by real-time PCR, significantly decreased in antibiotic treated specimens from 5 to 30 times in A. siro and T. putrescentiae, while no decline was observed in L. destructor. Streptomycin treatment eliminated Bartonella-like bacteria in the both A. siro and T. putrescentiae and Cardinium in T. putrescentiae. Solitalea-like bacteria proportion increased in the communities of neomycin and streptomycin treated A. siro specimens. Kocuria proportion increased in the bacterial communities of ampicillin and streptomycin treated A. siro and neomycin and streptomycin treated L. destructor.The work demonstrated the changes of mite associated bacterial community under antibiotic pressure in pests of medical importance. Pre-treatment of mites by 1 mg g(-1 antibiotic diets improved mite fitness as indicated accelerated population growth of A. siro pretreated streptomycin and neomycin and L. destructor pretreated by neomycin. All tested antibiotics supplemented to diets caused the decrease of mite growth rate in comparison to the control diet.

  7. 升华硫配合杀螨剂防治蜂螨效果的比较研究%Control Effect of Sublimed Sulfur Paired with Acaricide on Bee Mites

    Institute of Scientific and Technical Information of China (English)

    余玉生; 张祖芸; 卢焕仙; 赵洪木; 张学文

    2011-01-01

    [Objective] This study aimed to compare the effects of sublimed sulfur and acaricide on controlling bee mites. [Method] Three independent experiments were carried out in the same apiary during 2007 -2009. [Results] The results showed that this method is effective in eliminating mites settled on combs or hidden during pupae phase, but not in controlling the mites parasitized on adult bees. The control effect on killing Varroa destructor after treated appeared optimal in the first day and then decreased, and that on killing Tvopilaelaps clareae happened in the second day. The results indicated that the effect would be much better if the bees can be treated 1 time to 2 times again in the following 2 -5days after the first treatment. Back to data pool, we found that the treatment of sublimed sulfur paired with acaricide is effective in controlling V. destructor and T. clareae. [Conclusion] This technique could facilitate the apicultural production in the regions suffered from V. destructor and T. clareae.%[目的]比较升华硫配合杀蟥剂防治蜂螨效果.[方法]2007~2009年3年3次于同一个蜂场采用同一种方法对升华硫配合杀螨剂防治蜂螨效果进行了试验.[结果]升华硫配合杀螨剂对于消灭存在蜂脾上及寄生于封盖蛹的蜂螨有明显效果,对于消灭成年工蜂身体上的蜂螨效果不明显.施药后杀灭大蜂螨的效果以第1天最佳,此后逐日减少;杀灭小蜂螨的效果以第2天最佳,此后逐日减少,表明在2~5 d再施治1~2次,可达到理想的防治效果.[结论]该防治技术大、小蜂螨严重危害地区的养蜂生产提供服务.

  8. Infochemical use by predatory mites of the cassava green mite in a multitrophic context

    NARCIS (Netherlands)

    Gnanvossou, D.

    2002-01-01

    This thesis describes research on multitrophic interactions in a system consisting of (1) cassava plants ( Manihot esculenta ), (2) three herbivorous mites, i.e. the cassava green mite Mononychellus tanajoa, the red spider mite Oligonychus gossypii and the two-spotted spider mite Tetranychus urticae

  9. Comparação econômica entre controle biológico e químico para o manejo de ácaro-vermelho em macieira Economic comparison of biological and chemical control in the management of red spider mites in apple orchard

    Directory of Open Access Journals (Sweden)

    Lino Bittencourt Monteiro

    2006-12-01

    Full Text Available O ácaro-vermelho da macieira, Panonychus ulmi (Acari: Tetranychidae, é uma importante praga na cultura da macieira em Fraiburgo - SC, e o controle biológico aplicado foi implantado em meados dos anos 90. O objetivo deste trabalho foi demonstrar os benefícios econômicos da utilização do controle biológico no manejo do ácaro-vermelho. A avaliação foi realizada em dois pomares comerciais de macieiras. Em um deles, foi implantado o controle biológico aplicado de ácaros, baseado na liberação do ácaro predador Neoseiulus californicus (Acari: Phytoseiidae, seleção de inseticidas e manejo de ervas invasoras, e o outro pomar seguiu o manejo convencional de artrópodes, baseado na aplicação de produtos químicos para o controle de insetos, ácaros fitófagos e ervas invasoras. A análise econômica mostrou que os custos com mão-de-obra e máquinas foram semelhantes em ambos os pomares, entretanto os custos com acaricidas foram significativamente inferiores no pomar onde o manejo foi o controle biológico, demonstrando que, apesar da necessidade de investimentos em instalações para a criação do ácaro predador e custos de manutenção das mesmas, a estratégia biológica foi economicamente viável.Red spider mite, Panonychus ulmi (Acari: Tetranychidae is a significant pest in apple tree in Fraiburgo, Santa Catarina (SC and applied biological control was implemented in the mid-nineties. The objective of this study was to demonstrate the economic benefits of biological control in the management of red spider mite. The assessment was carried out in two commercial orchards, one of which was subjected to biological control of spider mite by releasing the predator Neoseiulus californicus, insecticide selection and weed management, and the other to conventional arthropod management, based on the application of chemicals to control insects, phytofagous mites and weed. Economic analysis showed that the costs for labor and machines were

  10. Human Demodex Mite: The Versatile Mite of Dermatological Importance

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    Parvaiz Anwar Rather

    2014-01-01

    Full Text Available Demodex mite is an obligate human ecto-parasite found in or near the pilo-sebaceous units. Demodex folliculorum and Demodex brevis are two species typically found on humans. Demodex infestation usually remains asymptomatic and may have a pathogenic role only when present in high densities and also because of immune imbalance. All cutaneous diseases caused by Demodex mites are clubbed under the term demodicosis or demodicidosis, which can be an etiological factor of or resemble a variety of dermatoses. Therefore, a high index of clinical suspicion about the etiological role of Demodex in various dermatoses can help in early diagnosis and appropriate, timely, and cost effective management.

  11. Human demodex mite: the versatile mite of dermatological importance.

    Science.gov (United States)

    Rather, Parvaiz Anwar; Hassan, Iffat

    2014-01-01

    Demodex mite is an obligate human ecto-parasite found in or near the pilo-sebaceous units. Demodex folliculorum and Demodex brevis are two species typically found on humans. Demodex infestation usually remains asymptomatic and may have a pathogenic role only when present in high densities and also because of immune imbalance. All cutaneous diseases caused by Demodex mites are clubbed under the term demodicosis or demodicidosis, which can be an etiological factor of or resemble a variety of dermatoses. Therefore, a high index of clinical suspicion about the etiological role of Demodex in various dermatoses can help in early diagnosis and appropriate, timely, and cost effective management.

  12. Disentangling mite predator-prey relationships by multiplex PCR.

    Science.gov (United States)

    Pérez-Sayas, Consuelo; Pina, Tatiana; Gómez-Martínez, María A; Camañes, Gemma; Ibáñez-Gual, María V; Jaques, Josep A; Hurtado, Mónica A

    2015-11-01

    Gut content analysis using molecular techniques can help elucidate predator-prey relationships in situations in which other methodologies are not feasible, such as in the case of trophic interactions between minute species such as mites. We designed species-specific primers for a mite community occurring in Spanish citrus orchards comprising two herbivores, the Tetranychidae Tetranychus urticae and Panonychus citri, and six predatory mites belonging to the Phytoseiidae family; these predatory mites are considered to be these herbivores' main biological control agents. These primers were successfully multiplexed in a single PCR to test the range of predators feeding on each of the two prey species. We estimated prey DNA detectability success over time (DS50), which depended on the predator-prey combination and ranged from 0.2 to 18 h. These values were further used to weight prey detection in field samples to disentangle the predatory role played by the most abundant predators (i.e. Euseius stipulatus and Phytoseiulus persimilis). The corrected predation value for E. stipulatus was significantly higher than for P. persimilis. However, because this 1.5-fold difference was less than that observed regarding their sevenfold difference in abundance, we conclude that P. persimilis is the most effective predator in the system; it preyed on tetranychids almost five times more frequently than E. stipulatus did. The present results demonstrate that molecular tools are appropriate to unravel predator-prey interactions in tiny species such as mites, which include important agricultural pests and their predators.

  13. Acaricidal activity of eugenol based compounds against scabies mites.

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    Cielo Pasay

    Full Text Available BACKGROUND: Human scabies is a debilitating skin disease caused by the "itch mite" Sarcoptes scabiei. Ordinary scabies is commonly treated with topical creams such as permethrin, while crusted scabies is treated with topical creams in combination with oral ivermectin. Recent reports of acaricide tolerance in scabies endemic communities in Northern Australia have prompted efforts to better understand resistance mechanisms and to identify potential new acaricides. In this study, we screened three essential oils and four pure compounds based on eugenol for acaricidal properties. METHODOLOGY/PRINCIPAL FINDINGS: Contact bioassays were performed using live permethrin-sensitive S. scabiei var suis mites harvested from pigs and permethrin-resistant S. scabiei var canis mites harvested from rabbits. Results of bioassays showed that clove oil was highly toxic against scabies mites. Nutmeg oil had moderate toxicity and ylang ylang oil was the least toxic. Eugenol, a major component of clove oil and its analogues--acetyleugenol and isoeugenol, demonstrated levels of toxicity comparable to benzyl benzoate, the positive control acaricide, killing mites within an hour of contact. CONCLUSIONS: The acaricidal properties demonstrated by eugenol and its analogues show promise as leads for future development of alternative topical acaricides to treat scabies.

  14. Repeatability of feather mite prevalence and intensity in passerine birds.

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    Javier Diaz-Real

    Full Text Available Understanding why host species differ so much in symbiont loads and how this depends on ecological host and symbiont traits is a major issue in the ecology of symbiosis. A first step in this inquiry is to know whether observed differences among host species are species-specific traits or more related with host-symbiont environmental conditions. Here we analysed the repeatability (R of the intensity and the prevalence of feather mites to partition within- and among-host species variance components. We compiled the largest dataset so far available: 119 Paleartic passerine bird species, 75,944 individual birds, ca. 1.8 million mites, seven countries, 23 study years. Several analyses and approaches were made to estimate R and adjusted repeatability (R(adj after controlling for potential confounding factors (breeding period, weather, habitat, spatial autocorrelation and researcher identity. The prevalence of feather mites was moderately repeatable (R = 0.26-0.53; R(adj = 0.32-0.57; smaller values were found for intensity (R = 0.19-0.30; R(adj = 0.18-0.30. These moderate repeatabilities show that prevalence and intensity of feather mites differ among species, but also that the high variation within species leads to considerable overlap among bird species. Differences in the prevalence and intensity of feather mites within bird species were small among habitats, suggesting that local factors are playing a secondary role. However, effects of local climatic conditions were partially observed for intensity.

  15. EFFICIENCY OF NEEM OIL ON CITRUS LEPROSIS MITE Brevipalpus phoenicis (GEIJSKES, 1939 CONTROL EFICIÊNCIA DO ÓLEO DE NEEM NO CONTROLE DO ÁCARO DA LEPROSE DOS CITROS Brevipalpus phoenicis (GEIJSKES, 1939

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    Cleber Daniel de Goes Maciel

    2009-01-01

    -bidi-language:#0400;}

    In order to determine the efficiency of neem oil on citrus leprosis mite, Brevipalpus pho