Sample records for indoor allergens endotoxin

  1. Are Cockroaches an Important Source of Indoor Endotoxins?

    PubMed

    Lai, Ka Man

    2017-01-18

    Endotoxins are common indoor biocontaminants. Their levels have been shown to link to many sources and factors. One of them is cockroach infestation but the role of cockroaches and contamination mechanisms are unclear. We hypothesized that not only is cockroach infestation a sign of poor hygiene, but it also contributes to indoor endotoxins via fecal contamination. In this study, different cockroach species were caught in homes. The endotoxin and allergen levels and their ratios in cockroach feces were determined. To estimate the amount of indoor endotoxins that originated from cockroaches, a new approach of using these new cockroach endotoxin and allergen ratios to compare with environmental data was employed. We found that Supella (S.) longipalpa , Periplaneta (P.) australasiae , and Blattella (B.) germanica were dominant in homes. On average, P. australasiae feces had a higher level but greater variation of endotoxins. B. germanica feces had the highest levels of allergens measured. Depending on environmental bacterial load and the type of cockroaches present, cockroach endotoxins in the environment may vary greatly. Cockroaches directly contribute to indoor endotoxins rather than just being a sign of poor hygiene. The type and extent of cockroach infestation should be taken into consideration when assessing and remediating indoor endotoxin contamination.

  2. Are Cockroaches an Important Source of Indoor Endotoxins?

    PubMed Central

    Lai, Ka Man

    2017-01-01

    Endotoxins are common indoor biocontaminants. Their levels have been shown to link to many sources and factors. One of them is cockroach infestation but the role of cockroaches and contamination mechanisms are unclear. We hypothesized that not only is cockroach infestation a sign of poor hygiene, but it also contributes to indoor endotoxins via fecal contamination. In this study, different cockroach species were caught in homes. The endotoxin and allergen levels and their ratios in cockroach feces were determined. To estimate the amount of indoor endotoxins that originated from cockroaches, a new approach of using these new cockroach endotoxin and allergen ratios to compare with environmental data was employed. We found that Supella (S.) longipalpa, Periplaneta (P.) australasiae, and Blattella (B.) germanica were dominant in homes. On average, P. australasiae feces had a higher level but greater variation of endotoxins. B. germanica feces had the highest levels of allergens measured. Depending on environmental bacterial load and the type of cockroaches present, cockroach endotoxins in the environment may vary greatly. Cockroaches directly contribute to indoor endotoxins rather than just being a sign of poor hygiene. The type and extent of cockroach infestation should be taken into consideration when assessing and remediating indoor endotoxin contamination. PMID:28106812

  3. Indoor Allergens and Allergic Respiratory Disease

    PubMed Central

    Chapman, Martin D.; Wünschmann, Sabina

    2016-01-01

    Purpose of review The purpose of this review is to evaluate the most recent findings on indoor allergens and their impact on allergic diseases. Recent findings Indoor allergens are present inside buildings (home, work environment, school), and given the chronic nature of the exposures, indoor allergies tend to be associated with the development of asthma. The most common indoor allergens are derived from dust mites, cockroaches, mammals (including wild rodents and pets), and fungi. The advent of molecular biology and proteomics has led to the identification, cloning, and expression of new indoor allergens, which have facilitated research to elucidate their role in allergic diseases. This review is an update on new allergens and their molecular features, together with the most recent reports on their avoidance for allergy prevention and their use for diagnosis and treatment. Summary Research progress on indoor allergens will result in the development of new diagnostic tools and design of coherent strategies for immunotherapy. PMID:27184001

  4. Household characteristics and allergen and endotoxin levels in Aleppo, Syrian Arab Republic.

    PubMed

    Al Ali, W; Custovic, A; Simpson, A; Khoury, A; Woodcock, A

    2010-07-01

    Few data are available from Eastern Mediterranean countries about levels of domestic allergens and endotoxins. Dust samples were collected from mattresses and floors of 457 homes in the Syrian city of Aleppo and analysed for antigens and endotoxins. The most important predictors for detectable levels of house-dust mite allergen Der p 1 were Arabic-style houses (OR 3.21) and newer houses (OR 1.56). In homes without cats, rubber mattresses were associated with detectable cat allergen Fel d 1 in mattress dust (OR 1.6). Cockroach allergen Bla g 2 was significantly more likely to be detected in houses over 20 years old than newer houses. Endotoxin levels were significantly higher in wool/cotton mattresses and older houses.

  5. ALLERGEN PROVOCATION AUGMENTS ENDOTOXIN-INDUCED NASAL INFLAMMATION IN ATOPIC ASTHMATICS

    EPA Science Inventory

    Background: Recent epidemiologic and in vivo studies have suggested that inhaled endotoxin plays an important role in asthma pathogenesis.
    Objective: The present study examines the effect of nasal allergen provocation on subsequent endotoxin challenges in subjects with atopi...

  6. Endotoxins in indoor air and settled dust in primary schools in a subtropical climate.

    PubMed

    Salonen, Heidi; Duchaine, Caroline; Létourneau, Valérie; Mazaheri, Mandana; Clifford, Sam; Morawska, Lidia

    2013-09-03

    Endotoxins can significantly affect the air quality in school environments. However, there is currently no reliable method for the measurement of endotoxins, and there is a lack of reference values for endotoxin concentrations to aid in the interpretation of measurement results in school settings. We benchmarked the "baseline" range of endotoxin concentration in indoor air, together with endotoxin load in floor dust, and evaluated the correlation between endotoxin levels in indoor air and settled dust, as well as the effects of temperature and humidity on these levels in subtropical school settings. Bayesian hierarchical modeling indicated that the concentration in indoor air and the load in floor dust were generally (<95th percentile) <13 EU/m(3) and <24,570 EU/m(2), respectively. Exceeding these levels would indicate abnormal sources of endotoxins in the school environment and the need for further investigation. Metaregression indicated no relationship between endotoxin concentration and load, which points to the necessity for measuring endotoxin levels in both the air and settled dust. Temperature increases were associated with lower concentrations in indoor air and higher loads in floor dust. Higher levels of humidity may be associated with lower airborne endotoxin concentrations.

  7. Indoor dust and air concentrations of endotoxin in urban and rural environments.

    PubMed

    Barnig, C; Reboux, G; Roussel, S; Casset, A; Sohy, C; Dalphin, J-C; de Blay, F

    2013-03-01

    Rural dairy farming is associated with high exposure to indoor endotoxins as compared to rural nonfarming houses and urban houses. The time spent on the mattress (7 h for an adult) and of the proximity of the contaminated source should be taken into account with the other causes of exposure. Studies in European children from a farming background have shown that these children have a reduced risk of asthma and atopic sensitization compared to their urban counterparts. It has been suggested that this might be due to exposure to high levels of endotoxin in the farming environment. The aim of this study was to compare indoor endotoxin concentrations in air and dust samples from randomly selected urban and rural dwellings. In the rural area, endotoxins were analysed in farmhouses and nonfarmhouses as well as housing characteristics, lifestyle factors and agricultural practices likely to influence air and dust endotoxin levels. Endotoxin levels were significantly higher in floor (6600 ± 6100 vs 3600 ± 5600 and 3800 ± 17,000 ng g⁻¹; P < 0·001) and mattress dust (2900 ± 4100 vs 1100 ± 2400 and 800 ± 2600 ng g⁻¹; P < 0·001) from farmhouses compared to other rural and urban homes. However, no difference was observed between endotoxin concentrations in the air of urban and rural houses, and airborne endotoxin levels did not correlate to dust levels. Lack of ventilation and direct entry into the house were correlated with an increase in dust endotoxin levels. These results confirm that dairy farming is associated with high exposure to endotoxins in indoor dust samples. No difference was observed between indoor airborne concentrations between urban and rural houses. These results suggest that measuring endotoxin in dust is the most relevant method to assess endotoxin exposure. © 2012 The Society for Applied Microbiology.

  8. Safety and benefits of inhaled hypertonic saline following airway challenges with endotoxin and allergen in asthmatics.

    PubMed

    Alexis, Neil E; Bennett, William; Peden, David Blaine

    2017-11-01

    To determine whether induced sputum (IS) with hypertonic saline inhalation is safe to use in asthmatics within 24 hours of two commonly used airway challenges, namely endotoxin and dust mite allergen, and to assess whether IS can enhance mucociliary clearance (MCC) rates in asthmatics. IS (three 7-minute inhalation periods of 3%, 4%, and 5% hypertonic saline) was employed before (N = 29) and within 24 hours of inhaled challenges with endotoxin (N = 13) and dust mite allergen (N = 12) in a cohort of mild to moderate asthmatics. Safety was assessed by lung function (Forced Expiratory Volume in 1 second; FEV1) and MCC was measured using a radiolabeled gamma scintigraphy method (Tcm99 sulfur colloid). IS was performed pre and post MCC. No significant lung function decrement was observed before or after inhaled challenges with endotoxin or dust mite allergen. IS significantly enhanced MCC rates before and after inhaled endotoxin challenge. Based on a small cohort, IS is safe to use in mild to moderate asthmatics before and within 24 hours of inhaled challenges with endotoxin and dust mite allergen. Furthermore, IS has beneficial effects on host defense function in asthmatics by enhancing MCC rates.

  9. Airborne endotoxin concentrations in indoor and outdoor particulate matter and their predictors in an urban city.

    PubMed

    Yoda, Y; Tamura, K; Shima, M

    2017-09-01

    Endotoxins are an important biological component of particulate matter and have been associated with adverse effects on human health. There have been some recent studies on airborne endotoxin concentrations. We collected fine (PM 2.5 ) and coarse (PM 10-2.5 ) particulate matter twice on weekdays and weekends each for 48 hour, inside and outside 55 homes in an urban city in Japan. Endotoxin concentrations in both fractions were measured using the kinetic Limulus Amebocyte Lysate assay. The relationships between endotoxin concentrations and household characteristics were evaluated for each fraction. Both indoor and outdoor endotoxin concentrations were higher in PM 2.5 than in PM 10-2.5 . In both PM 2.5 and PM 10-2.5 , indoor endotoxin concentrations were higher than outdoor concentrations, and the indoor endotoxin concentrations significantly correlated with outdoor concentrations in each fraction (R 2 =0.458 and 0.198, respectively). Indoor endotoxin concentrations in PM 2.5 were significantly higher in homes with tatami or carpet flooring and in homes with pets, and lower in homes that used air purifiers. Indoor endotoxin concentrations in PM 10-2.5 were significantly higher in homes with two or more children and homes with tatami or carpet flooring. These results showed that the indoor endotoxin concentrations were associated with the household characteristics in addition to outdoor endotoxin concentrations. © 2017 The Authors. Indoor Air Published by John Wiley & Sons Ltd.

  10. Short-term dynamics of indoor and outdoor endotoxin exposure: Case of Santiago, Chile, 2012.

    PubMed

    Barraza, Francisco; Jorquera, Héctor; Heyer, Johanna; Palma, Wilfredo; Edwards, Ana María; Muñoz, Marcelo; Valdivia, Gonzalo; Montoya, Lupita D

    2016-01-01

    Indoor and outdoor endotoxin in PM2.5 was measured for the very first time in Santiago, Chile, in spring 2012. Average endotoxin concentrations were 0.099 and 0.094 [EU/m(3)] for indoor (N=44) and outdoor (N=41) samples, respectively; the indoor-outdoor correlation (log-transformed concentrations) was low: R=-0.06, 95% CI: (-0.35 to 0.24), likely owing to outdoor spatial variability. A linear regression model explained 68% of variability in outdoor endotoxins, using as predictors elemental carbon (a proxy of traffic emissions), chlorine (a tracer of marine air masses reaching the city) and relative humidity (a modulator of surface emissions of dust, vegetation and garbage debris). In this study, for the first time a potential source contribution function (PSCF) was applied to outdoor endotoxin measurements. Wind trajectory analysis identified upwind agricultural sources as contributors to the short-term, outdoor endotoxin variability. Our results confirm an association between combustion particles from traffic and outdoor endotoxin concentrations. For indoor endotoxins, a predictive model was developed but it only explained 44% of endotoxin variability; the significant predictors were tracers of indoor PM2.5 dust (Si, Ca), number of external windows and number of hours with internal doors open. Results suggest that short-term indoor endotoxin variability may be driven by household dust/garbage production and handling. This would explain the modest predictive performance of published models that use answers to household surveys as predictors. One feasible alternative is to increase the sampling period so that household features would arise as significant predictors of long-term airborne endotoxin levels. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Indoor determinants of dustborne allergens in Mexican homes

    PubMed Central

    Hernández-Cadena, Leticia; Zeldin, Darryl C.; Sever, Michelle L.; Sly, Peter D.; London, Stephanie J.; Escamilla-Nuñez, María Consuelo; Romieu, Isabelle

    2015-01-01

    Exposure to indoor allergens represents a significant risk factor for allergies and asthma in several parts of the world. In Mexico, few studies have evaluated indoor allergens, including cat, dog, and mouse allergens and the factors that predict their presence. This study evaluates the main environmental and household predictors of high prenatal allergen levels and multiple allergen exposures in a birth cohort from Mexico City. A cross-sectional study was conducted as part of a birth cohort study of 1094 infants recruited during pregnancy and followed until delivery. We collected dust samples in a subset of 264 homes and assessed environmental factors. Der p 1, Der f 1, dust mite group 2, Fel d 1, Can f 1, Rat n 1, Mus m 1, and Bla g 2 concentrations in dust samples were measured using immunoassays. To define detectable allergen levels, the lowest limits of detection for each allergen were taken as cutoff points. Overall allergen exposure was considered high when four or more allergens exceeded detectable levels in the same household. Logistic regression was used for predictive models. Eighty-five percent of homes had at least one allergen in dust over the detection limit, 52.1% had high exposure (four or more allergens above detectable limits), and 11.7% of homes had detectable levels for more than eight allergens. Der p 1, Der p 2, Mus m 1, and Fel d 1 were the most frequent allergens detected. Each allergen had both common and distinct predictors. The main predictors of a high multiple allergen index were the size of the home, pesticide use, mother's age, mother as homemaker, and season. Increased indoor environmental allergen exposure is mainly related to sociodemographic factors and household cleaning. PMID:25715241

  12. Indoor and outdoor particulate matter and endotoxin concentrations in an intensely agricultural county

    PubMed Central

    Pavilonis, Brian T.; Anthony, T. Renee; O’Shaughnessy, Patrick T.; Humann, Michael J.; Merchant, James A.; Moore, Genna; Thorne, Peter S.; Weisel, Clifford P.; Sanderson, Wayne T.

    2014-01-01

    The objectives of this study were to characterize rural populations’ indoor and outdoor exposure to PM10, PM2.5, and endotoxin and identify factors that influence these concentrations. Samples were collected at 197 rural households over five continuous days between 2007 and 2011. Geometric mean indoor PM10 (21.2 μg m−3) and PM2.5 (12.2 μg m−3) concentrations tended to be larger than outdoor PM10 (19.6 μg m−3) and PM2.5 (8.2 μg m−3) concentrations (PM10 p= 0.086; PM2.5 p <0.001). Conversely, GM outdoor endotoxin concentrations (1.93 EU m−3) were significantly larger than indoor (0.32 EU m−3) (p<0.001). Compared to measurements from previous urban studies, indoor and outdoor concentrations of PM10 and PM2.5 in the study area tended to be smaller while, ambient endotoxin concentrations measured outside rural households were 3-10 times larger. Contrary to our initial hypothesis, seasonality did not have a significant effect on mean ambient PM10 concentrations; however, endotoxin concentrations in the autumn were almost seven-times larger than winter. Excluding home cleanliness, the majority of agricultural and housing characteristics evaluated were found to be poorly associated with indoor and outdoor particulate and endotoxin concentrations. PMID:23321860

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

    PubMed Central

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

    2013-01-01

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

  14. Allergen endotoxins induce T-cell-dependent and non-IgE-mediated nasal hypersensitivity in mice.

    PubMed

    Iwasaki, Naruhito; Matsushita, Kazufumi; Fukuoka, Ayumi; Nakahira, Masakiyo; Matsumoto, Makoto; Akasaki, Shoko; Yasuda, Koubun; Shimizu, Takeshi; Yoshimoto, Tomohiro

    2017-01-01

    Allergen-mediated cross-linking of IgE on mast cells/basophils is a well-recognized trigger for type 1 allergic diseases such as allergic rhinitis (AR). However, allergens may not be the sole trigger for AR, and several allergic-like reactions are induced by non-IgE-mediated mechanisms. We sought to describe a novel non-IgE-mediated, endotoxin-triggered nasal type-1-hypersensitivity-like reaction in mice. To investigate whether endotoxin affects sneezing responses, mice were intraperitoneally immunized with ovalbumin (OVA), then nasally challenged with endotoxin-free or endotoxin-containing OVA. To investigate the role of T cells and mechanisms of the endotoxin-induced response, mice were adoptively transferred with in vitro-differentiated OVA-specific T H 2 cells, then nasally challenged with endotoxin-free or endotoxin-containing OVA. Endotoxin-containing, but not endotoxin-free, OVA elicited sneezing responses in mice independent from IgE-mediated signaling. OVA-specific T H 2 cell adoptive transfer to mice demonstrated that local activation of antigen-specific T H 2 cells was required for the response. The Toll-like receptor 4-myeloid differentiation factor 88 signaling pathway was indispensable for endotoxin-containing OVA-elicited rhinitis. In addition, LPS directly triggered sneezing responses in OVA-specific T H 2-transferred and nasally endotoxin-free OVA-primed mice. Although antihistamines suppressed sneezing responses, mast-cell/basophil-depleted mice had normal sneezing responses to endotoxin-containing OVA. Clodronate treatment abrogated endotoxin-containing OVA-elicited rhinitis, suggesting the involvement of monocytes/macrophages in this response. Antigen-specific nasal activation of CD4 + T cells followed by endotoxin exposure induces mast cell/basophil-independent histamine release in the nose that elicits sneezing responses. Thus, environmental or nasal residential bacteria may exacerbate AR symptoms. In addition, this novel phenomenon might

  15. Indoor allergens, environmental avoidance, and allergic respiratory disease.

    PubMed

    Bush, Robert K

    2008-01-01

    Indoor allergen exposure to sources such as house-dust mites, pets, fungi, and insects plays a significant role in patients with allergic rhinitis and asthma. The identification of the major allergens has led to methods that can quantitate exposure, e.g., immunoassays for Der p 1 in settled dust samples. Sensitization and the development of allergic respiratory disease result from complex genetic and environmental interactions. New paradigms that examine the role of other environmental factors, including exposure to proteases that can activate eosinophils and initiate Th2 responses, and epigenetics, are being explored. Recommendations for specific environmental allergen avoidance measures are discussed for house-dust mites, cockroaches, animal dander, and fungi. Specific measures to reduce indoor allergen exposure when vigorously applied may reduce the risk of sensitization and symptoms of allergic respiratory disease, although further research will be necessary to establish cost-effective approaches.

  16. ASSESSING ALLERGENICITY OF INDOOR AIR FUNGAL CONTAMINANTS

    EPA Science Inventory

    Assessing Allergenicity of Indoor Air Fungal Contaminants
    M D W Ward1, M E Viana2, N Haykal-Coates1, L B Copeland1, S H Gavett1, and MJ K Selgrade1. 1US EPA, ORD, NHEERL, RTP, NC, USA. 2NCSU, CVM, Raleigh, NC, USA.
    Rationale: The indoor environment has increased in impor...

  17. Allergens in indoor air: environmental assessment and health effects.

    PubMed

    Carrer, P; Maroni, M; Alcini, D; Cavallo, D

    2001-04-10

    It has been suggested that the increase in morbidity and mortality for asthma and allergies, may also be due to an increase in exposure to allergens in the modern indoor environment. Indoor allergen exposure is recognised as the most important risk factor for asthma in children. House dust mites, pets, insects, plants, moulds and chemical agents in the indoor environment are important causes of allergic diseases. House dust mites and their debris and excrements that contain the allergens are normally found in the home in beds, mattresses, pillows, carpets and furniture stuffing, but they have also been found in office environments. Domestic animals such as cats, dogs, birds and rodents may cause allergic asthma and rhinoconjunctivitis. The exposure usually occurs in homes, but also in schools and kindergartens where domestic animals are kept as pets or for education; moreover, cat and dog owners can bring allergens to public areas in their clothes. Allergy to natural rubber latex has become an important occupational health concern in recent years, particularly among healthcare workers; when powdered gloves are worn or changed, latex particles get into the air and workers are exposed to latex aerosolised antigens. To assess the environmental risk to allergen exposure or to verify if there is a causal relationship between the immunologic findings in a patient and his/her environmental exposure, sampling from the suspected environment may be necessary.

  18. Indoor airborne endotoxin assessment in homes of Paris newborn babies.

    PubMed

    Dassonville, C; Demattei, C; Vacquier, B; Bex-Capelle, V; Seta, N; Momas, I

    2008-12-01

    The aims of this study were first to assess airborne endotoxin levels in the dwellings of 162 newborns living in Paris twice during a 1-year period, and second, to identify predictors for endotoxin concentrations using questionnaire data in relation to housing factors and living conditions. Air samples were collected on a glass fiber filter in polystyrene filter holders, using a pump at a flow rate of 3.5 l/min for 24 h placed in the main room of the home. Endotoxin levels were measured using a chromogenic kinetic Limulus Amoebocyte Lysate test. Geometric means (geometric standard deviation) of airborne endotoxin levels at two different visits were respectively 0.509 (4.289) EU/m3 and 0.557 (3.029) EU/m3. Airborne endotoxin levels were significantly increased: (i) in cold season (P = 0.024), with (ii) the presence of visible cockroaches in the previous 12 months at home (P < 0.001), (iii) increased number of inhabitants per square meter (P = 0.012), (iv) the high frequency of cleaning with the floor cloths (P = 0.0014), and (v) the low frequency of vacuuming (P = 0.0045). This study provided for the first time airborne endotoxin levels issued from repeated measurements in Paris dwellings. PRACTICAL IMPLICATIONS This analysis contributed to identify a few factors that determined indoor airborne endotoxin levels. However, the predictive model including housing factors and living conditions poorly estimated endotoxin levels. Consequently, multiple samples and longer sampling periods might improve the estimate of long-term airborne endotoxin exposure especially its variability, in cohort studies.

  19. Endotoxin, ergosterol, fungal DNA and allergens in dust from schools in Johor Bahru, Malaysia- associations with asthma and respiratory infections in pupils.

    PubMed

    Norbäck, Dan; Markowicz, Pawel; Cai, Gui-Hong; Hashim, Zailina; Ali, Faridah; Zheng, Yi-Wu; Lai, Xu-Xin; Spangfort, Michael Dho; Larsson, Lennart; Hashim, Jamal Hisham

    2014-01-01

    There are few studies on associations between respiratory health and allergens, fungal and bacterial compounds in schools in tropical countries. The aim was to study associations between respiratory symptoms in pupils and ethnicity, chemical microbial markers, allergens and fungal DNA in settled dust in schools in Malaysia. Totally 462 pupils (96%) from 8 randomly selected secondary schools in Johor Bahru, Malaysia, participated. Dust was vacuumed from 32 classrooms and analysed for levels of different types of endotoxin as 3-hydroxy fatty acids (3-OH), muramic acid, ergosterol, allergens and five fungal DNA sequences. Multiple logistic regression was applied. Totally 13.1% pupils reported doctor's diagnosed asthma, 10.3% wheeze and 21.1% pollen or pet allergy. Indian and Chinese children had less atopy and asthma than Malay. Carbon dioxide levels were low (380-690 ppm). No cat (Fel d1), dog (Can f 1) or horse allergens (Ecu cx) were detected. The levels of Bloomia tropicalis (Blo t), house dust mite allergens (Der p 1, Der f 1, Der m 1) and cockroach allergens (Per a 1 and Bla g 1) were low. There were positive associations between levels of Aspergillus versicolor DNA and daytime breathlessness, between C14 3-OH and respiratory infections and between ergosterol and doctors diagnosed asthma. There were negative (protective) associations between levels of C10 3-OH and wheeze, between C16 3-OH and day time and night time breathlessness, between cockroach allergens and doctors diagnosed asthma. Moreover there were negative associations between amount of fine dust, total endotoxin (LPS) and respiratory infections. In conclusion, endotoxin at school seems to be mainly protective for respiratory illness but different types of endotoxin could have different effects. Fungal contamination measured as ergosterol and Aspergillus versicolor DNA can be risk factors for respiratory illness. The ethnical differences for atopy and asthma deserve further attention.

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

    PubMed

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

    2010-02-01

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

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

    PubMed Central

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

    2010-01-01

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

  2. [Air quality in schools - classroom levels of carbon dioxide (CO2), volatile organic compounds (VOC), aldehydes, endotoxins and cat allergen].

    PubMed

    Fromme, H; Heitmann, D; Dietrich, S; Schierl, R; Körner, W; Kiranoglu, M; Zapf, A; Twardella, D

    2008-02-01

    Children are assumed to be more vulnerable to health hazards and spend a large part of their time in schools. To assess the exposure situation in this microenvironment, we evaluated the indoor air quality in winter 2004/5 in 92 classrooms, and in 75 classrooms in summer 2005 in south Bavaria, Germany. Indoor air climate parameters (temperature, relative humidity), carbon dioxide (CO2) and various volatile organic compounds, aldehydes and ketones were measured. Additionally, cat allergen (Fel d1) and endotoxin (LAL-test) were analysed in the settled dust of school rooms. Data on room and building characteristics were collected by use of a standardised form. Only data collected during teaching hours were considered in analysis. The median indoor CO2 concentration in the classrooms ranged in the winter and summer period from 598 to 4 172 ppm and 480 to 1 875 ppm, respectively. While during the winter period in 92% of the classrooms the CO2 daily medians went above 1 000 ppm, the percentage of classrooms with increased CO2 concentration fell to 28% in summer. In winter, in 60% of classes the daily median CO2 concentration exceeded 1 500 ppm, while in summer this threshold was reached by only 9%. A high concentration of CO2 was associated with a high number of pupils, a low room surface area and a low room volume. The levels of total volatile organic compounds (TVOC) in classrooms ranged between 110 and 1 000 microg/m3 (median in winter 345 microg/m3, in summer 260 microg/m3). Acetone, formaldehyde and acetaldehyde were measured in concentrations from 14.0 to 911 microg/m3, from 3.1 to 46.1 microg/m3, and from 2.9 to 78 microg/m3, respectively. The other aldehydes were detected in minor amounts only. The median Fel d1 level in winter was 485 ng/g dust (20 to 45 160 ng/g) and in summer it was 417 ng/g (40-7 470 ng/g). We observed no marked differences between the two sampling periods and between smooth floors and rooms with carpeted floors. No differences were found

  3. Seasonal variation in airborne endotoxin levels in indoor environments with different micro-environmental factors in Seoul, South Korea.

    PubMed

    Hwang, Sung Ho; Park, Dong Jin; Park, Wha Me; Park, Dong Uk; Ahn, Jae Kyoung; Yoon, Chung Sik

    2016-02-01

    This study evaluated the variation over a year in airborne endotoxin levels in the indoor environment of five university laboratories in Seoul, South Korea, and examined the micro-environmental factors that influenced endotoxin levels. These included temperature, relative humidity, CO2, CO, illumination, and wind velocity. A total of 174 air samples were collected and analyzed using the kinetic limulus amebocyte lysate assay. Endotoxin levels ranged from <0.001 to 8.90EU/m(3), with an overall geometric mean of 0.240EU/m(3). Endotoxin levels showed significantly negative correlation with temperature (r=-0.529, p<0.001), CO2 (r=-0.213, p<0.001) and illumination (r=-0.538, p<0.001). Endotoxin levels tended to be higher in winter. Endotoxin levels in laboratories with rabbits were significantly higher than those of laboratories with mice. Multivariate regression analysis showed that the environmental factors affecting endotoxin levels were temperature (coefficient=-0.388, p<0.001) and illumination (coefficient=-0.370, p<0.001). Strategies aimed at reducing airborne endotoxin levels in the indoor environments may be most effective if they focus on illumination. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Endotoxin, Ergosterol, Fungal DNA and Allergens in Dust from Schools in Johor Bahru, Malaysia- Associations with Asthma and Respiratory Infections in Pupils

    PubMed Central

    Norbäck, Dan; Markowicz, Pawel; Cai, Gui-Hong; Hashim, Zailina; Ali, Faridah; Zheng, Yi-Wu; Lai, Xu-Xin; Spangfort, Michael Dho; Larsson, Lennart; Hashim, Jamal Hisham

    2014-01-01

    There are few studies on associations between respiratory health and allergens, fungal and bacterial compounds in schools in tropical countries. The aim was to study associations between respiratory symptoms in pupils and ethnicity, chemical microbial markers, allergens and fungal DNA in settled dust in schools in Malaysia. Totally 462 pupils (96%) from 8 randomly selected secondary schools in Johor Bahru, Malaysia, participated. Dust was vacuumed from 32 classrooms and analysed for levels of different types of endotoxin as 3-hydroxy fatty acids (3-OH), muramic acid, ergosterol, allergens and five fungal DNA sequences. Multiple logistic regression was applied. Totally 13.1% pupils reported doctor’s diagnosed asthma, 10.3% wheeze and 21.1% pollen or pet allergy. Indian and Chinese children had less atopy and asthma than Malay. Carbon dioxide levels were low (380–690 ppm). No cat (Fel d1), dog (Can f 1) or horse allergens (Ecu cx) were detected. The levels of Bloomia tropicalis (Blo t), house dust mite allergens (Der p 1, Der f 1, Der m 1) and cockroach allergens (Per a 1 and Bla g 1) were low. There were positive associations between levels of Aspergillus versicolor DNA and daytime breathlessness, between C14 3-OH and respiratory infections and between ergosterol and doctors diagnosed asthma. There were negative (protective) associations between levels of C10 3-OH and wheeze, between C16 3-OH and day time and night time breathlessness, between cockroach allergens and doctors diagnosed asthma. Moreover there were negative associations between amount of fine dust, total endotoxin (LPS) and respiratory infections. In conclusion, endotoxin at school seems to be mainly protective for respiratory illness but different types of endotoxin could have different effects. Fungal contamination measured as ergosterol and Aspergillus versicolor DNA can be risk factors for respiratory illness. The ethnical differences for atopy and asthma deserve further attention. PMID

  5. Endotoxin and β-(1,3)-glucan levels in automobiles: a pilot study.

    PubMed

    Wu, Francis Fu-Sheng; Wu, Mei-Wen; Chang, Chin-Fu; Lai, Shu-Mei; Pierse, Nevil; Crane, Julian; Siebers, Rob

    2010-01-01

    Exposure to bacterial endotoxin and fungal β-(1,3)-glucan in the indoor environment can induce respiratory symptoms. Automobiles are an exposure source of allergens but it is not known if, and how much exposure there is to endotoxin and fungal β-(1,3)-glucan. The objective of the study was to determine whether automobiles are a potential source of exposure to these microbial products. Dust was sampled from the passenger seats of 40 automobiles. Specific Limulus amoebocyte kinetic assays were used to measure endotoxin and β-(1,3)-glucan, respectively. Endotoxin and β-(1,3)-glucan was detected in all samples ranging from 19.9-247.0 EU/mg and 1.6-59.8 μg/g, respectively. There were no significant differences in endotoxin levels between automobiles of smokers and non-smokers, but β-(1,3)-glucan levels were about two-fold higher in the automobiles of non-smokers. In conclusion, endotoxin and β-(1,3)-glucan exposure in automobiles at levels found in our study may be of importance for asthmatics.

  6. Childhood asthma and indoor allergens: the classroom may be a culprit.

    PubMed

    Epstien, B L

    2001-10-01

    Asthma has become the most common chronic illness among children. Indoor environments appear to play a substantial role in the development of asthma. Recent studies indicate strong evidence of a causal relationship between exposure to certain indoor environmental pollutants and development and/or exacerbation of asthma in susceptible individuals. Allergens of concern include those produced by dust mites, cockroaches, cats, dogs, and molds. It is important to better understand this relationship and take preventive and corrective steps to reduce or eliminate these sources in schools, homes, and day care centers. Measures include tracking of asthma and allergic response incidents; monitoring for the presence of allergens and molds; effective cleaning procedures; prompt repair of water leaks and/or moisture problems; control of indoor relative humidity; and proper operation of heating, ventilation, and air conditioning (HVAC) systems.

  7. Indoor environmental quality in a 'low allergen' school and three standard primary schools in Western Australia.

    PubMed

    Zhang, G; Spickett, J; Rumchev, K; Lee, A H; Stick, S

    2006-02-01

    To investigate indoor environmental quality in classrooms, assessments were undertaken in a 'low allergen' school and three standard primary schools in Western Australia. Dust allergens, air pollutants and physical parameters were monitored in the four schools at four times (summer school term, autumn holiday, winter school term and winter holiday) in 2002. The levels of particulate matter (PM(10)) and volatile organic compounds were similar between the four primary schools. Although slightly decreased levels of dust-mite and cat allergens were observed in the 'low allergen' school, the reductions were not statistically significant and the allergen levels in all schools were much lower than the recommended sensitizing thresholds. However, significantly lower levels of relative humidity and formaldehyde level during summer-term were recorded in the 'low allergen' school. In conclusion, the evidence here suggests that the 'low allergen' school did not significantly improve the indoor environmental quality in classrooms. Practical Implications School is an important environment for children in terms of exposure to pollutants and allergens. By assessing the levels of key pollutants and allergens in a low allergen school and three standard primary schools in Western Australia, this study provides useful information for implementation of healthy building design that can improve the indoor environment in schools.

  8. Sensitisation to common allergens and respiratory symptoms in endotoxin exposed workers: a pooled analysis.

    PubMed

    Basinas, Ioannis; Schlünssen, Vivi; Heederik, Dick; Sigsgaard, Torben; Smit, Lidwien A M; Samadi, Sadegh; Omland, Oyvind; Hjort, Charlotte; Madsen, Anne Mette; Skov, Simon; Wouters, Inge M

    2012-02-01

    To test the hypotheses that current endotoxin exposure is inversely associated with allergic sensitisation and positively associated with non-allergic respiratory diseases in four occupationally exposed populations using a standardised analytical approach. Data were pooled from four epidemiological studies including 3883 Dutch and Danish employees in veterinary medicine, agriculture and power plants using biofuel. Endotoxin exposure was estimated by quantitative job-exposure matrices specific for the study populations. Dose-response relationships between exposure, IgE-mediated sensitisation to common allergens and self-reported health symptoms were assessed using logistic regression and generalised additive modelling. Adjustments were made for study, age, sex, atopic predisposition, smoking habit and farm childhood. Heterogeneity was assessed by analysis stratified by study. Current endotoxin exposure was dose-dependently associated with a reduced prevalence of allergic sensitisation (ORs of 0.92, 0.81 and 0.66 for low mediate, high mediate and high exposure) and hay fever (ORs of 1.16, 0.81 and 0.58). Endotoxin exposure was a risk factor for organic dust toxic syndrome, and levels above 100 EU/m(3) significantly increased the risk of chronic bronchitis (p<0.0001). Stratification by farm childhood showed no effect modification except for allergic sensitisation. Only among workers without a farm childhood, endotoxin exposure was inversely associated with allergic sensitisation. Heterogeneity was primarily present for biofuel workers. Occupational endotoxin exposure has a protective effect on allergic sensitisation and hay fever but increases the risk for organic dust toxic syndrome and chronic bronchitis. Endotoxin's protective effects are most clearly observed among agricultural workers.

  9. Residential indoor and outdoor coarse particles and associated endotoxin exposures

    NASA Astrophysics Data System (ADS)

    Wheeler, Amanda J.; Dobbin, Nina A.; Lyrette, Ninon; Wallace, Lance; Foto, Mark; Mallick, Ranjeeta; Kearney, Jill; Van Ryswyk, Keith; Gilbert, Nicolas L.; Harrison, Ian; Rispler, Kathleen; Héroux, Marie-Eve

    2011-12-01

    There is a growing body of evidence demonstrating that coarse particles (PM 10-2.5) have detrimental impacts upon health, especially for respiratory effects. There are limited data available for indoor residential exposures. Some data exist regarding the composition of this PM size fraction with emphasis on crustal elements and biological components. This study includes data from 146 homes sampled in Regina, Saskatchewan (SK) where 5-day integrated concurrent monitoring of indoor and outdoor coarse particles was conducted during the winter and summer of 2007. The coarse particle filters were subsequently analysed for endotoxin content to determine the contribution of this compound. Winter indoor geometric mean concentrations of coarse particles exceeded outdoor concentrations (3.73 μg m -3 vs 2.49 μg m -3; paired t-test p < 0.0001); however the reverse was found in summer (4.34 μg m -3 vs 8.82 μg m -3; paired t-test p < 0.0001). Linear regression indicated that winter predictors of indoor coarse particles were outdoor coarse particles, ventilation and presence of at least two or more occupants. During the summer, increased use of central air conditioning was associated with reduced coarse particles, while smoking and the presence of two or more occupants resulted in increased coarse particles. Endotoxin concentrations (EU μg -1) were lower indoors than outdoors in both seasons. Spatial variability of ambient coarse particles was assessed to determine the suitability of using a single monitoring station within a city to estimate exposure. The coefficients of variation between homes sampled simultaneously and the central monitoring station were calculated (median COV in summer = 15% and winter = 24%) and showed significant variability by week, especially during the summer months, suggesting a single site may be insufficient for characterizing exposure. Future studies should consider daily measurements per home to understand shorter term exposures and day to day

  10. Exposure and Sensitization to Pets Modify Endotoxin Association with Asthma and Wheeze.

    PubMed

    Mendy, Angelico; Wilkerson, Jesse; Salo, Päivi M; Cohn, Richard D; Zeldin, Darryl C; Thorne, Peter S

    2018-04-21

    Pets are major contributors of endotoxin in homes, but whether they influence endotoxin association with respiratory outcomes is unclear. To examine whether exposure and sensitization to dog and cat modify the relationship between endotoxin exposure and asthma and wheeze. We analyzed data from 6051 participants in the 2005-2006 cycle of the National Health and Nutrition Examination Survey (NHANES). House dust from bedroom floor and bedding was evaluated for endotoxin and for dog (Canis familiaris 1) and cat (Feline domesticus 1) allergens. The NHANES also collected data on respiratory outcomes and measured IgE specific to allergens. Associations of log-endotoxin and pet exposure with respiratory outcomes were examined, adjusting for covariates including pet avoidance. Dog and cat ownership among participants was 48.3% and 37.5%, respectively. Endotoxin geometric mean (SE) was 15.49 (0.50) EU/mg. Endotoxin and pet allergen levels were significantly higher in households with a dog or cat. Overall, endotoxin was positively associated with wheeze (odds ratio [OR], 1.30; 95% CI, 1.04-1.62), but not with asthma. However, in participants nonsensitized to dog, the odds of endotoxin association with wheeze were higher with exposure to dog allergen (OR, 1.80; 95% CI, 1.27-2.53; P interaction  = .048). In participants sensitized to cat and exposed to cat allergen, endotoxin became positively associated with asthma (OR, 1.92; 95% CI, 1.21-3.0; P interaction  = .040). With coexposure to dog and cat allergens, endotoxin association with asthma and wheeze was exacerbated (OR, 2.00; 95% CI, 1.04-3.83; P interaction  = .012 and OR, 1.88; 95% CI, 1.32-2.66; P interaction  = .016, respectively). Exposure to dog and cat allergens enhances the association of endotoxin with asthma and wheeze. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. All rights reserved.

  11. Endotoxin levels and contribution factors of endotoxins in resident, school, and office environments - A review

    NASA Astrophysics Data System (ADS)

    Salonen, Heidi; Duchaine, Caroline; Létourneau, Valérie; Mazaheri, Mandana; Laitinen, Sirpa; Clifford, Sam; Mikkola, Raimo; Lappalainen, Sanna; Reijula, Kari; Morawska, Lidia

    2016-10-01

    As endotoxin exposure has known effects on human health, it is important to know the generally existing levels of endotoxins as well as their contributing factors. This work reviews current knowledge on the endotoxin loads in settled floor dust, concentrations of endotoxins in indoor air, and different environmental factors potentially affecting endotoxin levels. The literature review consists of peer-reviewed manuscripts located using Google and PubMed, with search terms based on individual words and combinations. References from relevant articles have also been searched. Analysis of the data showed that in residential, school, and office environments, the mean endotoxin loads in settled floor dust varied between 660 and 107,000 EU/m2, 2180 and 48,000 EU/m2, and 2700 and 12,890 EU/m2, respectively. Correspondingly, the mean endotoxin concentrations in indoor air varied between 0.04 and 1610 EU/m3 in residences, and 0.07 and 9.30 EU/m3 in schools and offices. There is strong scientific evidence indicating that age of houses (or housing unit year category), cleaning, farm or rural living, flooring materials (the presence of carpets), number of occupants, the presence of dogs or cats indoors, and relative humidity affect endotoxin loads in settled floor dust. The presence of pets (especially dogs) was extremely strongly associated with endotoxin concentrations in indoor air. However, as reviewed articles show inconsistency, additional studies on these and other possible predicting factors are needed.

  12. THE ALLERGENIC POTENTIAL OF INDOOR AIR FUNGAL CONTAMINANTS

    EPA Science Inventory


    The Allergenic Potential of Indoor Air Fungal Contaminants
    Marsha D W Ward1, Michael E Viana2, Yongjoo Chung3, Najwa Haykal-Coates1, Lisa B Copeland1, Steven H Gavett1, and MaryJane K Selgrade1. 1US EPA, ORD, NHEERL, RTP, NC, USA. 2NCSU, CVM, Raleigh, NC, USA, 3 UNC, SPH,...

  13. Assessment of indoor environment in Paris child day care centers.

    PubMed

    Roda, Célina; Barral, Sophie; Ravelomanantsoa, Hanitriniala; Dusséaux, Murielle; Tribout, Martin; Le Moullec, Yvon; Momas, Isabelle

    2011-11-01

    Children are sensitive to indoor environmental pollution. Up until now there has been a lack of data on air quality in child day care centers. The aim of this study is to document the indoor environment quality of Paris child day care centers by repeated measurements, and to compare pollutant levels in child day care centers with levels in Paris dwellings. We selected 28 child day care centers frequented by a random sample of babies who participated in the PARIS birth cohort environmental investigation, and visited the child day care centers for one week twice in one year. Biological contaminants assessed were fungi, endotoxin, dust mite allergens, and chemical pollutants: aldehydes, volatile organic compounds and nitrogen dioxide (NO2). Relative humidity, temperature, and carbon dioxide levels were measured simultaneously. A standardized questionnaire was used to gather information about the buildings and their inhabitants. Airborne endotoxin levels in child day care centers were higher than those found in Paris dwellings. Dust mite allergens in child day care centers were below the threshold level for sensitization in the majority of samples, and in common with dwelling samples. Penicillium and Cladosporium were the most commonly identified genera fungi. The child day care center indoor/outdoor ratio for most chemical pollutants was above unity except for NO2, the levels for NO2 being significantly higher than those measured in homes. Chemical and biological contamination in child day care centers appears to be low, apart from endotoxin and NO2. Failure to take child exposure in child day care centers into account could result in an overestimation of children's exposure to other pollutants. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Are building-level characteristics associated with indoor allergens in the household?

    PubMed

    Rosenfeld, Lindsay; Chew, Ginger L; Rudd, Rima; Emmons, Karen; Acosta, Luis; Perzanowski, Matt; Acevedo-García, Dolores

    2011-02-01

    Building-level characteristics are structural factors largely beyond the control of those who live in them. We explored whether building-level characteristics and indoor allergens in the household are related. We examined the relationship between building-level characteristics and indoor allergens: dust mite, cat, cockroach, and mouse. Building-level characteristics measured were presence of pests (seeing cockroaches and rodents), building type (public housing, buildings zoned commercially and residentially, and building size), and building condition (building age and violations). Allergen cutpoints were used for categorical analyses and defined as follows: dust mite: >0.25 μg/g; cat: >1 μg/g; cockroach: >1 U/g; mouse: >1.6 μg/g. In fully adjusted linear analyses, neither dust mite nor cat allergen were statistically significantly associated with any building-level characteristics. Cockroach allergen was associated with the presence of cockroaches (2.07; 95% CI, 1.23, 3.49) and living in public housing (2.14; 95% CI, 1.07, 4.31). Mouse allergen was associated with the presence of rodents (1.70; 95% CI, 1.29, 2.23), and building size: living in a low-rise (<8 floors; 0.60; 95% CI, 0.42, 0.87) or high-rise (8 + floors; 0.50; 95% CI, 0.29, 0.88; compared with house/duplex). In fully adjusted logistic analyses, cat allergen was statistically significantly associated with living in a high-rise (6.29; 95% CI, 1.51, 26.21; compared with a house/duplex). Mouse allergen was associated with living in public housing (6.20; 95% CI, 1.01, 37.95) and building size: living in a low-rise (0.16; 95% CI, 0.05, 0.52) or high-rise (0.06; 95% CI, 0.01, 0.50; compared with a house/duplex). Issues concerning building size and public housing may be particularly critical factors in reducing asthma morbidity. We suggest that future research explore the possible improvement of these factors through changes to building code and violations adherence, design standards, and incentives for

  15. Domestic exposure to endotoxin and respiratory morbidity in former smokers with COPD

    PubMed Central

    Bose, S; Rivera-Mariani, F; Chen, R; Williams, D; Belli, A; Aloe, C; McCormack, MC; Breysse, PN; Hansel, NN

    2016-01-01

    Indoor air pollution has been linked to adverse COPD health, but specific causative agents have not yet been identified. We evaluated the role of indoor endotoxin exposure upon respiratory health in former smokers with COPD. Eighty-four adults with moderate to severe COPD were followed longitudinally and indoor air and dust samples collected at baseline, 3 and 6 months. Respiratory outcomes were repeatedly assessed at each time point. The associations between endotoxin exposure in air and settled dust and health outcomes were explored using generalizing estimating equations in multivariate models accounting for confounders. Dust endotoxin concentrations in the main living area were highest in spring and lowest in fall, while airborne endotoxins remained steady across seasons. Airborne and dust endotoxin concentrations were weakly correlated with one another (rs=+0.24, p = 0.005). Endotoxin concentrations were not significantly associated with respiratory symptoms, rescue medication use, quality of life, or severe exacerbations. In-vitro whole blood assays of the pro-inflammatory capacity of PM10 filters with and without endotoxin depletion demonstrated that the endotoxin component of indoor air pollution was not the primary trigger for IL-1β release Our findings support that endotoxin is not the major driver in the adverse effects of indoor PM upon COPD morbidity. PMID:26547489

  16. Domestic exposure to endotoxin and respiratory morbidity in former smokers with COPD.

    PubMed

    Bose, S; Rivera-Mariani, F; Chen, R; Williams, D; Belli, A; Aloe, C; McCormack, M C; Breysse, P N; Hansel, N N

    2016-10-01

    Indoor air pollution has been linked to adverse chronic obstructive pulmonary disease (COPD) health, but specific causative agents have not yet been identified. We evaluated the role of indoor endotoxin exposure upon respiratory health in former smokers with COPD. Eighty-four adults with moderate to severe COPD were followed longitudinally and indoor air and dust samples collected at baseline, 3 and 6 months. Respiratory outcomes were repeatedly assessed at each time point. The associations between endotoxin exposure in air and settled dust and health outcomes were explored using generalizing estimating equations in multivariate models accounting for confounders. Dust endotoxin concentrations in the main living area were highest in spring and lowest in fall, while airborne endotoxins remained steady across seasons. Airborne and dust endotoxin concentrations were weakly correlated with one another (rs  = +0.24, P = 0.005). Endotoxin concentrations were not significantly associated with respiratory symptoms, rescue medication use, quality of life, or severe exacerbations. In vitro whole-blood assays of the pro-inflammatory capacity of PM10 filters with and without endotoxin depletion demonstrated that the endotoxin component of indoor air pollution was not the primary trigger for interleukin-1β release. Our findings support that endotoxin is not the major driver in the adverse effects of indoor PM upon COPD morbidity. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Predictors of coarse particulate matter and associated endotoxin concentrations in residential environments

    NASA Astrophysics Data System (ADS)

    Bari, Md. Aynul; MacNeill, Morgan; Kindzierski, Warren B.; Wallace, Lance; Héroux, Marie-Ève; Wheeler, Amanda J.

    2014-08-01

    Exposure to coarse particulate matter (PM), i.e., particles with an aerodynamic diameter between 2.5 and 10 μm (PM10-2.5), is of increasing interest due to the potential for health effects including asthma, allergy and respiratory symptoms. Limited information is available on indoor and outdoor coarse PM and associated endotoxin exposures. Seven consecutive 24-h samples of indoor and outdoor coarse PM were collected during winter and summer 2010 using Harvard Coarse Impactors in a total of 74 Edmonton homes where no reported smoking took place. Coarse PM filters were subsequently analyzed for endotoxin content. Data were also collected on indoor and outdoor temperature, relative humidity, air exchange rate, housing characteristics and occupants' activities. During winter, outdoor concentrations of coarse PM (median = 6.7 μg/m3, interquartile range, IQR = 3.4-12 μg/m3) were found to be higher than indoor concentrations (median 3.4 μg/m3, IQR = 1.6-5.7 μg/m3); while summer levels of indoor and outdoor concentrations were similar (median 4.5 μg/m3, IQR = 2.3-6.8 μg/m3, and median 4.7 μg/m3, IQR = 2.1-7.9 μg/m3, respectively). Similar predictors were identified for indoor coarse PM in both seasons and included corresponding outdoor coarse PM concentrations, whether vacuuming, sweeping or dusting was performed during the sampling period, and number of occupants in the home. Winter indoor coarse PM predictors also included the number of dogs and indoor endotoxin concentrations. Summer median endotoxin concentrations (indoor: 0.41 EU/m3, outdoor: 0.64 EU/m3) were 4-fold higher than winter concentrations (indoor: 0.12 EU/m3, outdoor: 0.16 EU/m3). Other than outdoor endotoxin concentrations, indoor endotoxin concentration predictors for both seasons were different. Winter endotoxin predictors also included presence of furry pets and whether the vacuum had a high efficiency particulate air (HEPA) filter. Summer endotoxin predictors were problems with mice in the

  18. Controlling indoor allergens.

    PubMed

    Custovic, Adnan; Murray, Clare S; Gore, Robin B; Woodcock, Ashley

    2002-05-01

    Reading of this article reinforces the reader's knowledge of the role of allergen exposure in relation to asthma and its severity, as well as the relevance of allergen avoidance in the treatment of asthma. Initial literature search for existing evidence-based guidelines, reviews, and meta-analyses was carried out, and further literature searches were performed to review individual randomized controlled trials. Evidence level was graded according to the Scottish Intercollegiate Guidelines Network recommendations. There is good evidence for the link between mite and cockroach allergen exposure and sensitization, and between sensitization and asthma. For pet allergens, some studies found that exposure to pets in early life was associated with specific immunoglobulin E sensitization and allergic disease later in childhood, whereas others reported a protective effect. The effectiveness of allergen reduction in the treatment of asthma is suggested by studies in which the patients improve substantially when moved into the low-allergen environment of hospitals or high-altitude sanatoria. Because of limitations in the design of the most clinical of studies, we do not yet have a conclusive answer on the effectiveness of domestic aeroallergen avoidance. Minimizing the impact of identified environmental risk factors is an important first step to reduce the severity of asthma. Although environmental control is difficult, it should be an integral part of the overall management of sensitized patients. However, what is unclear is which patients would benefit and by how much, and whether the intervention is cost-effective. These questions will be answered satisfactorily only by large randomized trials.

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

    PubMed

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

    2001-01-01

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

  20. Occurrence of indoor allergens in Saudi Arabia

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

    Sorensen, H.; Gravesen, S.; Lind, P.

    1985-06-01

    Investigations on indoor airborne allergens in Saudi Arabia were performed by mold cultures and dust analyses by counter-current immunoelectrophoresis. Twenty fungal genera were isolated, with Aspergillus as the most often encountered. Most of the dust-bound fungi found are ubiquitous and common. Antibodies against Dermatophagoides pteronyssinus, cat- cow- and rat dander, and Cynodon dactylon pollen were used in the dust analyses. Animal antigens were found in five of the ten dust samples. House dust mites were extraordinarily rare. Pollen of Cynodon dactylon (Bermuda grass) was present in nearly all the samples, and in a concurrent clinical study this antigen was foundmore » to be the most common cause of perennial rhinitis.« less

  1. Personal endotoxin exposure in a panel study of school children with asthma

    PubMed Central

    2011-01-01

    Background Endotoxin exposure has been associated with asthma exacerbations and increased asthma prevalence. However, there is little data regarding personal exposure to endotoxin in children at risk, or the relation of personal endotoxin exposure to residential or ambient airborne endotoxin. The relation between personal endotoxin and personal air pollution exposures is also unknown. Methods We characterized personal endotoxin exposures in 45 school children with asthma ages 9-18 years using 376 repeated measurements from a PM2.5 active personal exposure monitor. We also assayed endotoxin in PM2.5 samples collected from ambient regional sites (N = 97 days) and from a subset of 12 indoor and outdoor subject home sites (N = 109 and 111 days, respectively) in Riverside and Whittier, California. Endotoxin was measured using the Limulus Amoebocyte Lysate kinetic chromogenic assay. At the same time, we measured personal, home and ambient exposure to PM2.5 mass, elemental carbon (EC), and organic carbon (OC). To assess exposure relations we used both rank correlations and mixed linear regression models, adjusted for personal temperature and relative humidity. Results We found small positive correlations of personal endotoxin with personal PM2.5 EC and OC, but not personal PM2.5 mass or stationary site air pollutant measurements. Outdoor home, indoor home and ambient endotoxin were moderately to strongly correlated with each other. However, in mixed models, personal endotoxin was not associated with indoor home or outdoor home endotoxin, but was associated with ambient endotoxin. Dog and cat ownership were significantly associated with increased personal but not indoor endotoxin. Conclusions Daily fixed site measurements of endotoxin in the home environment may not predict daily personal exposure, although a larger sample size may be needed to assess this. This conclusion is relevant to short-term exposures involved in the acute exacerbation of asthma. PMID:21810249

  2. Pantoea agglomerans: a mysterious bacterium of evil and good. Part II--Deleterious effects: Dust-borne endotoxins and allergens--focus on grain dust, other agricultural dusts and wood dust.

    PubMed

    Dutkiewicz, Jacek; Mackiewicz, Barbara; Lemieszek, Marta Kinga; Golec, Marcin; Skórska, Czesława; Góra-Florek, Anna; Milanowski, Janusz

    2016-01-01

    by extraction of bacterial mass in saline (CA-S), showed the ability of these extracts to evoke inflammatory and fibrotic changes in the lungs, to stimulate alveolar macrophages to produce superoxide anion (O2(-)), interleukin-1 (IL-1) and chemotactic factors for other macrophages and neutrophils, and to increase the pulmonary concentrations of toll-like receptors and chemokines. The most potent properties showed the CA-S which may be attributed to the allergenic properties of P. agglomerans proteins enhanced by the presence of the autologous endotoxin. The results of these experiments are in accord with the clinical studies which revealed a high reactivity of the agricultural and grain industry workers to allergenic extracts of P. agglomerans, and the presence in these populations of hypersensitivity pneumonitis and asthma cases caused by this bacterium. P. agglomerans has been also identified as a potential causative agent of allergic dermatitis in farmers and of allergic pulmonary disorders in cattle. In conclusion, similar to the cotton industry, also in the grain industry and in agriculture, Pantoea agglomerans should be regarded as one of the major causative agents of work-related diseases, caused by the adverse effects of protein allergens and endotoxin produced by this bacterium.

  3. Endotoxin predictors and associated respiratory outcomes differ with climate regions in the U.S.

    PubMed

    Mendy, Angelico; Wilkerson, Jesse; Salo, Pӓivi M; Cohn, Richard D; Zeldin, Darryl C; Thorne, Peter S

    2018-03-01

    Although endotoxin is a recognized cause of environmental lung disease, how its relationship with respiratory outcomes varies with climate is unknown. To examine the endotoxin predictors as well as endotoxin association with asthma, wheeze, and sensitization to inhalant allergens in various US climate regions. We analyzed data on 6963 participants in the National Health and Nutrition Examination Survey. Endotoxin measurements of house dust from bedroom floor and bedding were performed at the University of Iowa. Linear and logistic regression analyses were used to identify endotoxin predictors and assess endotoxin association with health outcomes. The overall median house dust endotoxin was 16.2 EU/mg; it was higher in mixed-dry/hot-dry regions (19.7 EU/mg) and lower in mixed-humid/marine areas (14.8 EU/mg). Endotoxin predictors and endotoxin association with health outcomes significantly differed across climate regions. In subarctic/very cold/cold regions, log 10 -endotoxin was significantly associated with higher prevalence of wheeze outcomes (OR:1.48, 95% CI:1.19-1.85 for any wheeze, OR:1.48, 95% CI:1.22-1.80 for exercise-induced wheeze, OR:1.50, 95% CI:1.13-1.98 for prescription medication for wheeze, and OR:1.95, 95% CI:1.50-2.54 for doctor/ER visit for wheeze). In hot-humid regions, log 10 -endotoxin was positively associated with any wheeze (OR:1.66, 95% CI:1.04-2.65) and current asthma (OR:1.56, 95% CI:1.11-2.18), but negatively with sensitization to any inhalant allergens (OR:0.83, 95% CI:0.74-0.92). Endotoxin predictors and endotoxin association with asthma and wheeze differ across U.S. climate regions. Endotoxin is associated positively with wheeze or asthma in cold and hot-humid regions, but negatively with sensitization to inhalant allergens in hot-humid climates. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    PubMed

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

    2006-12-01

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

  5. [New allergens and pediatric allergology].

    PubMed

    Eng, P A

    1998-09-30

    The first manifestation of allergies most often occurs in childhood. Prevention of atopic diseases is one of the very important tasks in pediatrics. Exact knowledge of allergens and the role of adjuvant factors in allergic sensitisation is necessary to define measures for allergy prevention aiming at a reduction of the worldwide increasing prevalence of atopic diseases. Indoor allergens and tobacco smoke exposure are risk factors for early sensitisation and asthma. In addition to house dust mites there are other indoor allergens like moulds, pet allergens, cockroaches and many more. Exact diagnosis and identification of the causative allergen allows therapy directing towards allergen avoidance and relieving symptoms without need of any additional pharmaceutical treatment. This cost-saving strategy helps to prevent disease-related long absences from school and work. Exact knowledge of the structure and biology of the etiologic allergens is a prerequisite for this treatment strategy. We review the great contribution of the Allergy Unit in Zurich to the identification and characterisation of environmental allergens.

  6. Indoor Residential Chemical Exposures as Risk Factors for Asthmaand Allergy in Infants and Children: a Review

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

    Mendell, M.J.

    2006-03-01

    Most research into effects of residential indoor air exposures on asthma and allergies has focused on exposures to biologic allergens, moisture and mold, endotoxin, or combustion byproducts. This paper briefly reviews reported findings on associations of asthma or allergy in infants or children with risk factors related to indoor chemical emissions from residential materials or surface coatings. Associations, some strong (e.g., odds ratios up to 13), were reported. The most frequently identified risk factors were formaldehyde, aromatic organic compounds such as toluene and benzene, plastic materials and plasticizers, and recent painting. Exposures and consequent effects from indoor sources may bemore » exacerbated by decreased ventilation. Identified risk factors may be proxies for correlated exposures. Findings suggest the frequent occurrence of important but preventable effects on asthma and allergy in infants and children worldwide from modern residential building materials and coatings.« less

  7. Temporal and spatial patterns of ambient endotoxin concentrations in Fresno, California.

    PubMed

    Tager, Ira B; Lurmann, Frederick W; Haight, Thaddeus; Alcorn, Siana; Penfold, Bryan; Hammond, S Katharine

    2010-10-01

    Endotoxins are found in indoor dust generated by human activity and pets, in soil, and adsorbed onto the surfaces of ambient combustion particles. Endotoxin concentrations have been associated with respiratory symptoms and the risk of atopy and asthma in children. We characterized the temporal and spatial variability of ambient endotoxin in Fresno/Clovis, California, located in California's Central Valley, to identify correlates and potential predictors of ambient endotoxin concentrations in a cohort of children with asthma [Fresno Asthmatic Children's Environment Study (FACES)]. Between May 2001 and October 2004, daily ambient endotoxin and air pollutants were collected at the central ambient monitoring site of the California Air Resources Board in Fresno and, for shorter time periods, at 10 schools and indoors and outdoors at 84 residences in the community. Analyses were restricted to May-October, the dry months during which endotoxin concentrations are highest. Daily endotoxin concentration patterns were determined mainly by meteorologic factors, particularly the degree of air stagnation. Overall concentrations were lowest in areas distant from agricultural activities. Highest concentrations were found in areas immediately downwind from agricultural/pasture land. Among three other measured air pollutants [fine particulate matter, elemental carbon (a marker of traffic in Fresno), and coarse particulate matter (PMc)], PMc was the only pollutant correlated with endotoxin. Endotoxin, however, was the most spatially variable. Our data support the need to evaluate the spatial/temporal variability of endotoxin concentrations, rather than relying on a few measurements made at one location, in studies of exposure and and respiratory health effects, particularly in children with asthma and other chronic respiratory diseases.

  8. Endotoxin Exposure: Predictors and Prevalence of Associated Asthma Outcomes in the United States

    PubMed Central

    Mendy, Angelico; Metwali, Nervana; Salo, Päivi; Co, Caroll; Jaramillo, Renee; Rose, Kathryn M.; Zeldin, Darryl C.

    2015-01-01

    Rationale: Inhaled endotoxin induces airway inflammation and is an established risk factor for asthma. The 2005–2006 National Health and Nutrition Examination Survey included measures of endotoxin and allergens in homes as well as specific IgE to inhalant allergens. Objectives: To understand the relationships between endotoxin exposure, asthma outcomes, and sensitization status for 15 aeroallergens in a nationally representative sample. Methods: Participants were administered questionnaires in their homes. Reservoir dust was vacuum sampled to generate composite bedding and bedroom floor samples. We analyzed 7,450 National Health and Nutrition Examination Survey dust and quality assurance samples for their endotoxin content using extreme quality assurance measures. Data for 6,963 subjects were available, making this the largest study of endotoxin exposure to date. Log-transformed endotoxin concentrations were analyzed using logistic models and forward stepwise linear regression. Analyses were weighted to provide national prevalence estimates and unbiased variances. Measurements and Main Results: Endotoxin exposure was significantly associated with wheeze in the past 12 months, wheeze during exercise, doctor and/or emergency room visits for wheeze, and use of prescription medications for wheeze. Models adjusted for age, sex, race and/or ethnicity, and poverty-to-income ratio and stratified by allergy status showed that these relationships were not dependent upon sensitization status but were worsened among those living in poverty. Significant predictors of higher endotoxin exposures were lower family income; Hispanic ethnicity; participant age; dog(s), cat(s), cockroaches, and/or smoker(s) in the home; and carpeted floors. Conclusions: In this U.S. nationwide representative sample, higher endotoxin exposure was significantly associated with measures of wheeze, with no observed protective effect regardless of sensitization status. PMID:26258643

  9. Streptomycetes in house dust: associations with housing characteristics and endotoxin

    EPA Science Inventory

    In addition to mold, indoor bioaerosols also contain bacterial components that may have implications for human health. Endotoxin is a cell wall component in Gram-negative bacteria present at varying levels indoors that has been found to have respiratory health implications. Stre...

  10. Sensitization to Indigenous Pollen and Molds and Other Outdoor and Indoor Allergens in Allergic Patients From Saudi Arabia, United Arab Emirates, and Sudan

    PubMed Central

    2012-01-01

    Background Airborne allergens vary from one climatic region to another. Therefore, it is important to analyze the environment of the region to select the most prevalent allergens for the diagnosis and treatment of allergic patients. Objective To evaluate the prevalence of positive skin tests to pollen and fungal allergens collected from local indigenous plants or isolated molds, as well as other outdoor and indoor allergens in allergic patients in 6 different geographical areas in the Kingdom of Saudi Arabia (KSA), the United Arab Emirates, and Sudan. Materials and methods Four hundred ninety-two consecutive patients evaluated at different Allergy Clinics (276 women and 256 men; mean age, 30 years) participated in this study. The selection of indigenous allergens was based on research findings in different areas from Riyadh and adjoining areas. Indigenous raw material for pollen grains was collected from the desert near the capital city of Riyadh, KSA. The following plants were included: Chenopodium murale, Salsola imbricata, Rumex vesicarius, Ricinus communis, Artiplex nummularia, Amaranthus viridis, Artemisia monosperma, Plantago boissieri, and Prosopis juliflora. Indigenous molds were isolated from air sampling in Riyadh and grown to obtain the raw material. These included the following: Ulocladium spp., Penicillium spp., Aspergillus fumigatus, Cladosporium spp., and Alternaria spp. The raw material was processed under Good Manufacturing Practices for skin testing. Other commercially available outdoor (grass and tree pollens) and indoor (mites, cockroach, and cat dander) allergens were also tested. Results The highest sensitization to indigenous pollens was detected to C. murale (32%) in Khartoum (Sudan) and S. imbricata (30%) and P. juliflora (24%) in the Riyadh region. The highest sensitization to molds was detected in Khartoum, especially to Cladosporium spp. (42%), Aspergillus (40%), and Alternaria spp. (38%). Sensitization to mites was also very prevalent

  11. Feasibility of using subject-collected dust samples in epidemiologic and clinical studies of indoor allergens.

    PubMed

    Arbes, Samuel J; Sever, Michelle; Vaughn, Ben; Mehta, Jigna; Lynch, Jeffrey T; Mitchell, Herman; Hoppin, Jane A; Spencer, Harvey L; Sandler, Dale P; Zeldin, Darryl C

    2005-06-01

    Studies of indoor allergen exposures are often limited by the cost and logistics of sending technicians to homes to collect dust. In this study we evaluated the feasibility of having subjects collect their own dust samples. The objectives were to compare allergen concentrations between subject- and technician-collected samples and to examine the sample return rate. Using a dust collection device and written instructions provided to them by mail, 102 subjects collected a combined dust sample from a bed and bedroom floor. Later the same day, a technician collected a side-by-side sample. Dust samples were weighed and analyzed for the cat allergen Fel d 1 and the dust mite allergen Der p 1. Fifty additional subjects who were enrolled by telephone were mailed dust collection packages and asked to return a dust sample and questionnaire by mail. A technician did not visit their homes. Correlations between subject- and technician-collected samples were strong for concentrations of Fel d 1 (r = 0.88) and Der p 1 (r = 0.87). With allergen concentrations dichotomized at lower limits of detection and clinically relevant thresholds, agreements between methodologies ranged from 91 to 98%. Although dust weights were correlated (r = 0.48, p < 0.001), subjects collected lighter samples. Among the group of 50 subjects, 46 returned a dust sample and completed questionnaire. The median number of days to receive a sample was 15. With some limitations, subject-collected dust sampling appears to be a valid and practical option for epidemiologic and clinical studies that report allergen concentration as a measure of exposure.

  12. Temporal and Spatial Patterns of Ambient Endotoxin Concentrations in Fresno, California

    PubMed Central

    Tager, Ira B.; Lurmann, Frederick W.; Haight, Thaddeus; Alcorn, Siana; Penfold, Bryan; Hammond, S. Katharine

    2010-01-01

    Background Endotoxins are found in indoor dust generated by human activity and pets, in soil, and adsorbed onto the surfaces of ambient combustion particles. Endotoxin concentrations have been associated with respiratory symptoms and the risk of atopy and asthma in children. Objective We characterized the temporal and spatial variability of ambient endotoxin in Fresno/Clovis, California, located in California’s Central Valley, to identify correlates and potential predictors of ambient endotoxin concentrations in a cohort of children with asthma [Fresno Asthmatic Children’s Environment Study (FACES)]. Methods Between May 2001 and October 2004, daily ambient endotoxin and air pollutants were collected at the central ambient monitoring site of the California Air Resources Board in Fresno and, for shorter time periods, at 10 schools and indoors and outdoors at 84 residences in the community. Analyses were restricted to May–October, the dry months during which endotoxin concentrations are highest. Results Daily endotoxin concentration patterns were determined mainly by meteorologic factors, particularly the degree of air stagnation. Overall concentrations were lowest in areas distant from agricultural activities. Highest concentrations were found in areas immediately downwind from agricultural/pasture land. Among three other measured air pollutants [fine particulate matter, elemental carbon (a marker of traffic in Fresno), and coarse particulate matter (PMc)], PMc was the only pollutant correlated with endotoxin. Endotoxin, however, was the most spatially variable. Conclusions Our data support the need to evaluate the spatial/temporal variability of endotoxin concentrations, rather than relying on a few measurements made at one location, in studies of exposure and and respiratory health effects, particularly in children with asthma and other chronic respiratory diseases. PMID:20494854

  13. Mouse allergen exposure and decreased risk of allergic rhinitis in school-aged children.

    PubMed

    Jacobs, Tammy S; Forno, Erick; Brehm, John M; Acosta-Pérez, Edna; Han, Yueh-Ying; Blatter, Joshua; Thorne, Peter; Metwali, Nervana; Colón-Semidey, Angel; Alvarez, María; Canino, Glorisa; Celedón, Juan C

    2014-12-01

    Little is known about exposure to mouse allergen (Mus m 1) and allergic rhinitis (AR). To evaluate the association between mouse allergen exposure and AR in children. We examined the relation between mouse allergen level in house dust and AR in 511 children aged 6 to 14 years in San Juan, Puerto Rico. Study participants were chosen from randomly selected households using a multistage probability sample design. The study protocol included questionnaires, allergy skin testing, and collection of blood and dust samples. AR was defined as current rhinitis symptoms and skin test reactivity to at least one allergen. In the multivariate analyses, mouse allergen level was associated with a 25% decreased odds of AR in participating children (95% confidence interval, 0.62-0.92). Although endotoxin and mouse allergen levels were significantly correlated (r = 0.184, P < .001), the observed inverse association between Mus m 1 and AR was not explained by levels of endotoxin or other markers of microbial or fungal exposure (peptidoglycan and glucan). Mouse allergen exposure is associated with decreased odds of AR in Puerto Rican school-aged children. Copyright © 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  14. Dust Allergens within Rural Northern Rocky Mountain Residences.

    PubMed

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

    2015-01-23

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

  15. Associations of neighborhood concentrated poverty, neighborhood racial/ethnic composition, and indoor allergen exposures: a cross-sectional analysis of los angeles households, 2006-2008.

    PubMed

    Camacho-Rivera, Marlene; Kawachi, Ichiro; Bennett, Gary G; Subramanian, S V

    2014-08-01

    Although racial/ethnic, socioeconomic, and neighborhood factors have been linked to asthma, and the association between indoor allergens and asthma is well documented, few studies have examined the relationship between these factors and indoor allergens. We examined the frequency of reported indoor allergens and differences by racial/ethnic, socioeconomic, and neighborhood characteristics among a diverse sample of Los Angeles households. Multilevel logistic regression models were used to analyze the data from 723 households from wave 2 of the Los Angeles Family and Neighborhood Survey. The reported presence of rats, mice, cockroaches, mold, pets, and tobacco smoke were the primary outcomes of interest. Hispanic and Asian households had a nearly threefold increase in the odds of reporting cockroaches compared to non-Hispanic Whites (OR, 2.85; 95 % CI 1.38-5.88 and OR, 2.62; 95 % CI 1.02-6.73, respectively) even after adjusting for socioeconomic factors. Primary caregivers who had obtained a high school degree were significantly less likely to report the presence of mice and cockroaches compared to primary caregivers with less than a high school degree (OR, 0.19; 95 % CI 0.08-0.46 and OR, 0.39; 95 % CI 0.23-0.68, respectively). Primary caregivers with more than a high school degree were also less likely to report the presence of rats, mice, and cockroaches within their households, compared to those with less than a high school degree. Compared to renters, home owners were less likely to report the presence of mice, cockroaches, and mold within their households. At the neighborhood level, households located within neighborhoods of high concentrated poverty (where the average poverty rate is at least 50 %) were more likely to report the presence of mice and cockroaches compared to households in low concentrated poverty neighborhoods (average poverty rate is 10 % or less), after adjusting for individual race/ethnicity and socioeconomic characteristics. Our study

  16. Endotoxin Exposure and Eczema in the First Year of Life

    PubMed Central

    Phipatanakul, Wanda; Celedón, Juan C.; Raby, Benjamin A.; Litonjua, Augusto A.; Milton, Donald K.; Sredl, Diane; Weiss, Scott T.; Gold, Diane R.

    2005-01-01

    Objective Exposure to endotoxin in early life has been proposed as a factor that may protect against the development of allergic diseases such as eczema. The objective of this study was to examine the relation between endotoxin exposure in early life and eczema in the first year of life in children with parental history of asthma or allergies. Methods This study used a prospective birth cohort study of 498 children who had a history of allergy or asthma in at least 1 parent and lived in metropolitan Boston. A subset of 401 living rooms had house dust samples adequate for analysis of endotoxin. Results In multivariate analyses adjusting for gender, income, and season of birth, endotoxin levels in the living room at 2 to 3 months of age was inversely associated with physician- or nurse-diagnosed eczema in the first year of life (odds ratio [OR] for each quartile increment: 0.76; 95% confidence interval [CI]: 0.61–0.96). Exposure to a dog in the home at age 2 to 3 months was also inversely associated with eczema in the first year of life, but the CI widened when endotoxin was included in the multivariate model (OR: 0.54; 95% CI: 0.27–1.09). Other variables associated with eczema in the first year of life included paternal history of eczema (OR: 1.91; 95% CI: 1.03–3.55) and maternal specific immunoglobulin E positivity to ≥1 allergen (OR: 1.61; 95% CI: 1.01–2.56). Conclusions Among children with parental history of asthma or allergies, exposure to high levels of endotoxin in early life may be protective against eczema in the first year of life. In these children, paternal history of eczema and maternal sensitization to at least 1 allergen are associated with an increased risk of eczema in the first year of life. PMID:15231902

  17. Endotoxins in urban air in Stockholm, Sweden

    NASA Astrophysics Data System (ADS)

    Nilsson, S.; Merritt, A. S.; Bellander, T.

    2011-01-01

    Endotoxins, i.e. components originating from the outer membrane in the cell wall of Gram-negative bacteria, activate the human immune system, which may result in airway symptoms such as shortness of breath and airway inflammation. Endotoxins are present in the environment, both outdoors and indoors, and stay airborne for a long time. In order to investigate the levels of endotoxins in urban air and the influence of traffic and meteorological factors, particles (PM 10 and PM 2.5) were collected at five sites in Stockholm, Sweden on four occasions per site between May and September 2009. Endotoxins were extracted from the filters and analysis was conducted with the Limulus Amebocyte Lysate (LAL)-assay. Endotoxins were present in urban air in Stockholm, albeit in low levels, and were similar to levels found in urban areas outside Sweden. To our knowledge, this is the northernmost location where endotoxins have been measured. The endotoxin levels found in PM 10 ranged from 0.020 to 0.107 EU m -3 with a geometric mean of 0.050 EU m -3 and the levels found in PM 2.5 ranged from 0.005 to 0.064 EU m -3 with a geometric mean of 0.015 EU m -3. No obvious effects of traffic or meteorological factors on endotoxin levels were observed, although a moderate correlation could be seen with soot. The small number of sampling sites is however a shortcoming of the present study. In future studies, more sites and sampling during all seasons would be preferable in order to get a better picture of the influence of different sources on endotoxin levels.

  18. LOW-DOSE AIRBORNE ENDOTOXIN EXPOSURE ENHANCES BRONCHIAL RESPONSIVENESS TO INHALED ALLERGEN IN ATOPIC ASTHMATICS

    EPA Science Inventory

    Endotoxin exposure has been associated with both protection against development of TH2-immune responses during childhood and exacerbation of asthma in persons who already have allergic airway inflammation.1 Occupational and experimental inhalation exposures to endotoxin have been...

  19. Allergenic proteins are fragmented in low concentrations of sodium hypochlorite.

    PubMed

    Chen, P; Eggleston, P A

    2001-07-01

    To facilitate allergen removal from indoor environments, it would be helpful to have household cleaning products that modified allergenic activity. Because NaOCl dissolves proteins in high concentrations and is both capable of killing bacteria and viruses and inactivating viral antigens at somewhat lower concentrations, we explored its effects on Mus m 1 and other indoor allergens. To examine the ability of NaOCl to reduce the allergenicity of Mus m 1 and other indoor allergens. Using purified mouse urinary allergen, we examined the effect on protein measured by Coomassie protein assay and on Mus m 1 measured by ELISA. We also examined the effects using SDS/PAGE and Western blots probed with sheep anti-Mus m 1 and with allergic human serum. When NaOCl and Mus m 1 were combined in a molar ratio of 100 : 1, IgE binding to Mus m 1 on Western blot was significantly reduced. At higher NaOCl concentrations the protein appeared to fragment and eventually became undetectable. Fragmentation appeared to be random in that peptides of a wide range of apparent molecular weight were produced. The reaction was complete within 1-2 min at OCl : pr ratios of greater than 200 : 1 and was optimal at pH 7.4. Immunological activity of other allergens (Fel d 1, Bla g 1, Der p 1) was decreased in vitro and dried allergen extracts were removed from surfaces. Adding an extraneous protein, BSA, to NaOCl:Mus m 1 solutions decreased the effect of NaOCl on the allergen. We concluded that NaOCl at concentrations commonly used in household products is capable of dramatically affecting allergenic protein.

  20. Indoor Environmental Control Practices and Asthma Management.

    PubMed

    Matsui, Elizabeth C; Abramson, Stuart L; Sandel, Megan T

    2016-11-01

    Indoor environmental exposures, particularly allergens and pollutants, are major contributors to asthma morbidity in children; environmental control practices aimed at reducing these exposures are an integral component of asthma management. Some individually tailored environmental control practices that have been shown to reduce asthma symptoms and exacerbations are similar in efficacy and cost to controller medications. As a part of developing tailored strategies regarding environmental control measures, an environmental history can be obtained to evaluate the key indoor environmental exposures that are known to trigger asthma symptoms and exacerbations, including both indoor pollutants and allergens. An environmental history includes questions regarding the presence of pets or pests or evidence of pests in the home, as well as knowledge regarding whether the climatic characteristics in the community favor dust mites. In addition, the history focuses on sources of indoor air pollution, including the presence of smokers who live in the home or care for children and the use of gas stoves and appliances in the home. Serum allergen-specific immunoglobulin E antibody tests can be performed or the patient can be referred for allergy skin testing to identify indoor allergens that are most likely to be clinically relevant. Environmental control strategies are tailored to each potentially relevant indoor exposure and are based on knowledge of the sources and underlying characteristics of the exposure. Strategies include source removal, source control, and mitigation strategies, such as high-efficiency particulate air purifiers and allergen-proof mattress and pillow encasements, as well as education, which can be delivered by primary care pediatricians, allergists, pediatric pulmonologists, other health care workers, or community health workers trained in asthma environmental control and asthma education. Copyright © 2016 by the American Academy of Pediatrics.

  1. EXPOSURE OF CHILDREN TO INDOOR MOLDS

    EPA Science Inventory

    Children now spend more than 90% of their time indoors. Thus, any exposure to indoor pollutants may be critical to their health. Molds are one of the most important pollutants children are exposed to indoors. Molds produce hundreds of allergens and toxins. These products ha...

  2. Allergens in Urban Schools and Homes of Children with Asthma

    PubMed Central

    Permaul, Perdita; Hoffman, Elaine B.; Fu, Chunxia; Sheehan, William J.; Baxi, Sachin N.; Gaffin, Jonathan M.; Lane, Jeffrey P.; Bailey, Ann; King, Eva; Chapman, Martin D.; Gold, Diane R.; Phipatanakul, Wanda

    2012-01-01

    Background Most studies of indoor allergens have focused on the home environment. However, schools may be an important site of allergen exposure for children with asthma. We compared school allergen exposure to home exposure in a cohort of children with asthma. Correlations between settled dust and airborne allergen levels in classrooms were examined. Methods Settled dust and airborne samples from 12 inner-city schools were analyzed for indoor allergens using multiplex array technology (MARIA). School samples were linked to students with asthma enrolled in the School Inner-City Asthma Study (SICAS). Settled dust samples from students’ bedrooms were analyzed similarly. Results From schools, 229 settled dust and 197 airborne samples were obtained. From homes, 118 settled dust samples were obtained. Linear mixed regression models of log-transformed variables showed significantly higher settled dust levels of mouse, cat and dog allergens in schools than homes (545% higher for Mus m 1, estimated absolute difference 0.55 μg/g, p<0.0001; 198% higher for Fel d 1, estimated absolute difference 0.13 μg/g, p=0.0033; and 144% higher for Can f 1, estimated absolute difference 0.05 μg/g, p=0.0008). Airborne and settled dust Mus m 1 levels in classrooms were moderately correlated (r=0.48; p< 0.0001). There were undetectable to very low levels of cockroach and dust mite allergens in both homes and schools. Conclusions Mouse allergen levels in schools were substantial. In general, cat and dog allergen levels were low, but detectable, and were higher in schools. Aerosolization of mouse allergen in classrooms may be a significant exposure for students. Further studies are needed to evaluate the effect of indoor allergen exposure in schools on asthma morbidity in students with asthma. PMID:22672325

  3. Surface sampling for endotoxin assessment using electrostatic wiping cloths.

    PubMed

    Thorne, Peter S; Metwali, Nervana; Avol, Ed; McConnell, Rob S

    2005-07-01

    Much of the cost of exposure assessment for studies of residential cohorts is in scheduling and travel time for field staff. One way to reduce costs is to simplify methods such that subjects can sample their own residence. Analysis of settled dust is being widely used for assessment of exposures to allergens, lead and pesticides and can also be used for endotoxins. While vacuum sampling is the most common surface sampling method, wipe sampling has the advantage that it can be readily performed by the resident when convenient and samples can then be mailed to researchers. Thus, we evaluated the feasibility of wipe sampling for endotoxin environmental assessment using electrostatic wipes with or without the use of disposable examination gloves. Multiple lots of six types of commercial wipes and eight types of gloves were extracted and analyzed for endotoxin content using the kinetic chromogenic Limulus amebocyte lysate assay. Wipes were compared across brands, between lots, within lots, between pairs depending on proximity to cardboard packaging, and in wipe tests with or without gloves. Collected dust samples of known concentration were also tested in spiking assays for endotoxin recovery. The most striking finding was the high variability of endotoxin contamination of both wipes and gloves across brands and between various lots. The content of endotoxin in unused gloves ranged from <1.5 to 5810 endotoxin units (EU). The range for unused wipes was 3.6-87.8 EU. Surfaces of equal loading and area were sampled using three types of cloths that had low initial endotoxin contamination. The cloths were very good at collecting dust and endotoxin could be assayed from aqueous extracts of the wipes. Samples collected using cloths with bare washed hands yielded higher endotoxin loading per mass of collected dust versus samples collected wearing endotoxin-free gloves. This demonstrated additional endotoxin loading from the subject's hand. This study shows that wipe sampling

  4. Endotoxin Exposure during Sensitization to Blomia tropicalis Allergens Shifts TH2 Immunity Towards a TH17-Mediated Airway Neutrophilic Inflammation: Role of TLR4 and TLR2

    PubMed Central

    Barboza, Renato; Câmara, Niels Olsen Saraiva; Gomes, Eliane; Sá-Nunes, Anderson; Florsheim, Esther; Mirotti, Luciana; Labrada, Alexis; Alcântara-Neves, Neuza Maria; Russo, Momtchilo

    2013-01-01

    Experimental evidence and epidemiological studies indicate that exposure to endotoxin lipopolysaccharide (eLPS) or other TLR agonists prevent asthma. We have previously shown in the OVA-model of asthma that eLPS administration during alum-based allergen sensitization blocked the development of lung TH2 immune responses via MyD88 pathway and IL-12/IFN-γ axis. In the present work we determined the effect of eLPS exposure during sensitization to a natural airborne allergen extract derived from the house dust mite Blomia tropicalis (Bt). Mice were subcutaneously sensitized with Bt allergens co-adsorbed onto alum with or without eLPS and challenged twice intranasally with Bt. Cellular and molecular parameters of allergic lung inflammation were evaluated 24 h after the last Bt challenge. Exposure to eLPS but not to ultrapure LPS (upLPS) preparation during sensitization to Bt allergens decreased the influx of eosinophils and increased the influx of neutrophils to the airways. Inhibition of airway eosinophilia was not observed in IFN-γdeficient mice while airway neutrophilia was not observed in IL-17RA-deficient mice as well in mice lacking MyD88, CD14, TLR4 and, surprisingly, TLR2 molecules. Notably, exposure to a synthetic TLR2 agonist (PamCSK4) also induced airway neutrophilia that was dependent on TLR2 and TLR4 molecules. In the OVA model, exposure to eLPS or PamCSK4 suppressed OVA-induced airway inflammation. Our results suggest that B. tropicalis allergens engage TLR4 that potentiates TLR2 signaling. This dual TLR activation during sensitization results in airway neutrophilic inflammation associated with increased frequency of lung TH17 cells. Our work highlight the complex interplay between bacterial products, house dust mite allergens and TLR signaling in the induction of different phenotypes of airway inflammation. PMID:23805294

  5. Indoor and Outdoor Allergies.

    PubMed

    Singh, Madhavi; Hays, Amy

    2016-09-01

    In last 30 to 40 years there has been a significant increase in the incidence of allergy. This increase cannot be explained by genetic factors alone. Increasing air pollution and its interaction with biological allergens along with changing lifestyles are contributing factors. Dust mites, molds, and animal allergens contribute to most of the sensitization in the indoor setting. Tree and grass pollens are the leading allergens in the outdoor setting. Worsening air pollution and increasing particulate matter worsen allergy symptoms and associated morbidity. Cross-sensitization of allergens is common. Treatment involves avoidance of allergens, modifying lifestyle, medical treatment, and immunotherapy. Copyright © 2016 Elsevier Inc. All rights reserved.

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

    PubMed

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

    2016-01-01

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

  7. Airborne Mold and Endotoxin Concentrations in New Orleans, Louisiana, after Flooding, October through November 2005

    PubMed Central

    Solomon, Gina M.; Hjelmroos-Koski, Mervi; Rotkin-Ellman, Miriam; Hammond, S. Katharine

    2006-01-01

    Background The hurricanes and flooding in New Orleans, Louisiana, in October and November 2005 resulted in damp conditions favorable to the dispersion of bioaerosols such as mold spores and endotoxin. Objective Our objective in this study was to assess potential human exposure to bioaerosols in New Orleans after the flooding of the city. Methods A team of investigators performed continuous airborne sampling for mold spores and endotoxin outdoors in flooded and nonflooded areas, and inside homes that had undergone various levels of remediation, for periods of 5–24 hr during the 2 months after the flooding. Results The estimated 24-hr mold concentrations ranged from 21,000 to 102,000 spores/m3 in outdoor air and from 11,000 to 645,000 spores/m3 in indoor air. The mean outdoor spore concentration in flooded areas was roughly double the concentration in nonflooded areas (66,167 vs. 33,179 spores/m3; p < 0.05). The highest concentrations were inside homes. The most common mold species were from the genera of Cladosporium and Aspergillus/Penicillium; Stachybotrys was detected in some indoor samples. The airborne endotoxin concentrations ranged from 0.6 to 8.3 EU (endo-toxin units)/m3 but did not vary with flooded status or between indoor and outdoor environments. Conclusions The high concentration of mold measured indoors and outdoors in the New Orleans area is likely to be a significant respiratory hazard that should be monitored over time. Workers and returning residents should use appropriate personal protective equipment and exposure mitigation techniques to prevent respiratory morbidity and long-term health effects. PMID:16966092

  8. The Role of Allergen Exposure and Avoidance in Asthma

    PubMed Central

    Baxi, Sachin N.; Phipatanakul, Wanda

    2010-01-01

    Allergy testing and avoidance of allergens plays an important role in asthma control. Increased allergen exposure, in genetically susceptible individuals, can lead to allergic sensitization. Continued allergen exposure can increase the risk of asthma and other allergic diseases. In a patient with persistent asthma, identification of indoor and outdoor allergens and subsequent avoidance can improve symptoms. Often times, a patient will have multiple allergies and the avoidance plan should target all positive allergens. Several studies have shown that successful allergen remediation includes a comprehensive approach including education, cleaning, physical barriers and maintaining these practices. PMID:20568555

  9. Seasonal Variations of Indoor Microbial Exposures and Their Relation to Temperature, Relative Humidity, and Air Exchange Rate

    PubMed Central

    Bekö, Gabriel; Timm, Michael; Gustavsen, Sine; Hansen, Erik Wind

    2012-01-01

    Indoor microbial exposure has been related to adverse pulmonary health effects. Exposure assessment is not standardized, and various factors may affect the measured exposure. The aim of this study was to investigate the seasonal variation of selected microbial exposures and their associations with temperature, relative humidity, and air exchange rates in Danish homes. Airborne inhalable dust was sampled in five Danish homes throughout the four seasons of 1 year (indoors, n = 127; outdoors, n = 37). Measurements included culturable fungi and bacteria, endotoxin, N-acetyl-beta-d-glucosaminidase, total inflammatory potential, particles (0.75 to 15 μm), temperature, relative humidity, and air exchange rates. Significant seasonal variation was found for all indoor microbial exposures, excluding endotoxin. Indoor fungi peaked in summer (median, 235 CFU/m3) and were lowest in winter (median, 26 CFU/m3). Indoor bacteria peaked in spring (median, 2,165 CFU/m3) and were lowest in summer (median, 240 CFU/m3). Concentrations of fungi were predominately higher outdoors than indoors, whereas bacteria, endotoxin, and inhalable dust concentrations were highest indoors. Bacteria and endotoxin correlated with the mass of inhalable dust and number of particles. Temperature and air exchange rates were positively associated with fungi and N-acetyl-beta-d-glucosaminidase and negatively with bacteria and the total inflammatory potential. Although temperature, relative humidity, and air exchange rates were significantly associated with several indoor microbial exposures, they could not fully explain the observed seasonal variations when tested in a mixed statistical model. In conclusion, the season significantly affects indoor microbial exposures, which are influenced by temperature, relative humidity, and air exchange rates. PMID:23001651

  10. Environment and development of respiratory allergy. II. Indoors.

    PubMed

    D'Amato, G; Liccardi, G; D'Amato, M

    1994-12-01

    Even if it is difficult to obtain correct epidemiological evidence, there is a body of evidence which suggests that the frequency of allergic respiratory diseases is increasing. The majority of atopic patients, in particular in childhood and adolescence, develop immunoglobulin E (IgE) antibodies with clinical symptoms to aeroallergens, such as those derived from house dust mites, pollens and pets. Since, in the economically-developed countries individuals spend most of their time indoors (home, school and workplace), indoor pollutants (tobacco smoke etc.) and allergens (house dust mite, cats, etc.) are the most important source of exposure. Indoor allergens are associated with a wide variety of particles in a broad size range, only some of which are microscopically identifiable, culturable, or detectable with existing immunoassay. Evaluation of indoor allergens requires both air and source sampling, and several different analytical techniques. It is likely that the increased prevalence of allergy and asthma may be caused in the indoor environment by the synergistic action of air pollution (in particular derived from tobacco smoking) with allergic sensitization. Passive smoking in infancy has also been involved in the airways allergic sensitization to common aeroallergens.

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

    PubMed Central

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

    2016-01-01

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

  12. Reducing indoor air pollutants with air filtration units in wood stove homes.

    PubMed

    McNamara, Marcy L; Thornburg, Jonathon; Semmens, Erin O; Ward, Tony J; Noonan, Curtis W

    2017-08-15

    Biomass burning has been shown to be a major source of poor indoor air quality (IAQ) in developing and higher income countries across the world. Specifically, wood burning for cooking and heating contributes to high indoor concentrations of fine (particles with aerodynamic diameters<2.5μm; PM 2.5 ) and coarse (particles with aerodynamic diameters <10μm and >2.5μm; PMc) particulate matter. Endotoxin, predominantly found within the coarse fraction of airborne particulate matter, is associated with proinflammatory effects and adverse outcomes among susceptible populations. The aim of this study was to assess the efficacy of air filter interventions in reducing indoor PM 2.5 , PMc, and PMc-associated endotoxin concentrations in homes using a wood stove for primary heating. Homes (n=48) were randomized to receive in-room air filtration units with either a high efficiency filter (i.e. active) or a lower efficiency fiberglass filter (i.e., placebo). The active filter intervention showed a 66% reduction in indoor PM 2.5 concentrations (95% CI: 42.2% to 79.7% reduction) relative to the placebo intervention. Both the active and the placebo filters were effective in substantially reducing indoor concentrations of PMc (63.3% and 40.6% average reduction for active and placebo filters, respectively) and PMc-associated endotoxin concentrations (91.8% and 80.4% average reductions, respectively). These findings support the use of high efficiency air filtration units for reducing indoor PM 2.5 in homes using a wood stove for primary heating. We also discovered that using lower efficiency, lower cost filter alternatives can be effective for reducing PMc and airborne endotoxin in homes burning biomass fuel. Copyright © 2017. Published by Elsevier B.V.

  13. Alternaria and Cladosporium Fungal Allergen Epitopes are Denatured by Sodium Hypochlorite

    PubMed Central

    2009-01-01

    Background Fungal allergens are ubiquitous; however, little progress has been made understanding fungal allergenic material removal from indoor environments. Purpose We investigated removal of environmental allergenic material derived from Alternaria and Cladosporium using sodium hypochlorite in vivo and in vitro. Methods Freeze dried allergen extract from Alternaria alternata and Cladosporium herbarum was treated with hypochlorite concentrations of 322, 88, 38, 16, 3, 0.3, and 0 mM, respectively. Remaining native allergenic material was quantified using enzyme immunoassay and remaining viable fungal material was evaluated. Results The results of treating Alternaria or Cladosporium extract with sodium hypochlorite are immediate and obvious. Concentrations greater than 100 mM remove color and concentrations between 100 and 38 mM partially uncolored the extract. Immunoassay for total antigenic and allergenic material remaining after treatment with sodium hypochlorite including 2 concentrations recommended for killing fungus confirmed a general destruction of antigenic and allergenic material at concentrations of 38 mM or greater. Conclusions This work confirms the ability of solutions of sodium hypochlorite to denature fungal allergenic material from common outdoor and indoor fungi A. alternata and C. herbarum. Destruction of recognized antigenic and allergenic epitopes occurs at hypochlorite concentrations commonly used for household cleaning. PMID:23282316

  14. Assessment of Environmental Cockroach Allergen Exposure

    PubMed Central

    Chew, Ginger L.

    2016-01-01

    In the past, cockroach allergen exposure assessment mainly focused on settled dust in homes in low-income urban cities in the United States. That choice was not wrong; without measureable levels of cockroach allergen, it is difficult to show associations with any home characteristics much less with health outcomes (e.g., allergy, asthma). However, recent studies in other suburban areas, schools, and other countries have elucidated the importance of cockroach allergen in these environments too. In addition, characterizing the underlying factors that give rise to cockroach allergen exposure (or protect against it) can lead to more targeted public health interventions. This review discusses different approaches to sampling indoor environments, interprets recent asthma and allergy studies, compares cockroach allergen levels from past studies with those of recent studies, and describes strategies to decrease exposures. PMID:22825884

  15. Dog allergen (Can f 1) and cat allergen (Fel d 1) in US homes: Results from the National Survey of Lead and Allergens in Housing

    PubMed Central

    Arbes, Samuel J.; Cohn, Richard D.; Yin, Ming; Muilenberg, Michael L.; Friedman, Warren; Zeldin, Darryl C.

    2017-01-01

    Background Exposures to dog and cat allergens are believed to play important roles in the etiology of asthma; however, the levels of these allergens have never been assessed in a representative sample of US homes. Objective The objective of this study was to estimate and characterize exposures to Can f 1 (dog allergen) and Fel d 1 (cat allergen) in US homes. Methods Data were obtained from the National Survey of Lead and Allergens in Housing, a nationally representative survey of 831 US homes. Vacuumed-collected dust samples from the bed, bedroom floor, living room floor, and living room sofa were analyzed for concentrations of Can f 1 and Fel d 1 (micrograms of allergen per gram of dust). Results Although a dog or cat had lived in only 49.1% of homes in the previous 6 months, Can f 1 and Fel d 1 were detected in 100% and 99.9% of homes, respectively. Averaged over the sampled sites, geometric mean concentrations (µg/g) were 4.69 for Can f 1 and 4.73 for Fel d 1. Among homes with an indoor dog and cat, respectively, geometric mean concentrations were 69 for Can f 1 and 200 for Fel d 1. Among homes without the indoor pet, geometric mean concentrations were above 1.0. The independent predictors of elevated concentrations in homes without pets were all demographic variables that were also linked to a higher prevalence of pet ownership. Conclusions Can f 1 and Fel d 1 are universally present in US homes. Levels that have been associated with an increased risk of allergic sensitization were found even in homes without pets. Because of the transportability of these allergens on clothing, elevated levels in homes without pets, particularly among demographic groups in which pet ownership is more prevalent, implicate the community as an important source of these pet allergens. PMID:19055206

  16. Deteriorated housing contributes to high cockroach allergen levels in inner-city households.

    PubMed Central

    Rauh, Virginia A; Chew, Ginger R; Garfinkel, Robin S

    2002-01-01

    The high prevalence of childhood asthma in low-income, inner-city populations is not fully understood but has been at least partly attributed to the disproportionate exposures associated with socioeconomic disadvantage. The contribution of indoor allergens to asthma is well documented, but links between socioeconomic disadvantage and indoor allergen levels are not clear. We investigated levels of cockroach allergens (Bla g 2) in a sample of 132 Dominican or African American low-income households with young children in northern Manhattan in New York City (40% were receiving public assistance) to determine whether the distribution of allergens is a function of housing deterioration. Deterioration was measured by the presence and number of physical housing problems (holes in the ceilings and walls, water damage, etc.). More than 50% of the sample had two or more types of housing dilapidation, and 67% of the sample reported cockroach sightings in their homes. Samples of dust were collected from kitchen and bedroom surfaces. We hypothesized that the greater the dilapidation, the higher the allergen levels, independent of income, sociocultural factors, and pest-control methods. In addition, we hypothesized that the homes of families characterized by frequent moves (23.5%) would have higher allergen levels than more stable families. Results showed significant positive associations between housing deterioration and allergen levels in kitchens, after adjusting for income and ethnicity, with independent effects of residential stability (p< 0.05). Bedroom allergen levels were associated with housing instability (p < 0.01) and ethnicity (p< 0.01). Findings demonstrated that indoor household allergen levels are related to degree of household disrepair, after adjusting for individual family attributes, suggesting that social-structural aspects of housing may be appropriate targets for public health interventions designed to reduce allergen exposure. PMID:11929744

  17. Evaluation of home allergen sampling devices.

    PubMed

    Sercombe, J K; Liu-Brennan, D; Garcia, M L; Tovey, E R

    2005-04-01

    Simple, inexpensive methods of sampling from allergen reservoirs are necessary for large-scale studies or low-cost householder-operated allergen measurement. We tested two commercial devices: the Indoor Biotechnologies Mitest Dust Collector and the Drager Bio-Check Allergen Control; two devices of our own design: the Electrostatic Cloth Sampler (ECS) and the Press Tape Sampler (PTS); and a Vacuum Sampler as used in many allergen studies (our Reference Method). Devices were used to collect dust mite allergen samples from 16 domestic carpets. Results were examined for correlations between the sampling methods. With mite allergen concentration expressed as microg/g, the Mitest, the ECS and the PTS correlated with the Reference Method but not with each other. When mite allergen concentration was expressed as microg/m2 the Mitest and the ECS correlated with the Reference Method but the PTS did not. In the high allergen conditions of this study, the Drager Bio-Check did not relate to any methods. The Mitest Dust Collector, the ECS and the PTS show performance consistent with the Reference Method. Many techniques can be used to collect dust mite allergen samples. More investigation is needed to prove any method as superior for estimating allergen exposure.

  18. Indoor pollution and its impact on respiratory health.

    PubMed

    Bardana, E J

    2001-12-01

    This overview discusses the respiratory complications of indoor air pollution, emphasizing the most common pollutants that individuals are likely to encounter outside the workplace. Data were obtained from a review of the recent literature. The expert opinion of the author was used to select and synthesize relevant data on this multifaceted subject. There have been a number of studies documenting an association between exposure to indoor allergens and development of both sensitization and asthma in children. In addition to classic allergens, chemical indoor air pollution may also exert an adverse effect on both the upper and lower respiratory tract by a variety of nonimmunologic, irritative mechanisms. Our understanding of the adverse effects of indoor air pollution on health and comfort has broadened in recent years. It has supplied a credible framework for developing and implementing a variety of control strategies.

  19. Relationship between chicken cellular immunity and endotoxin levels in dust from chicken housing environments

    PubMed Central

    Roque, Katharine; Shin, Kyung-Min; Jo, Ji-Hoon; Kim, Hyoung-Ah

    2015-01-01

    Hazardous biochemical agents in animal husbandry indoor environments are known to promote the occurrence of various illnesses among workers and animals. The relationship between endotoxin levels in dust collected from chicken farms and various immunological markers was investigated. Peripheral blood was obtained from 20 broiler chickens and 20 laying hens from four different chicken farms in Korea. Concentrations of total or respirable dust in the inside the chicken farm buildings were measured using a polyvinyl chloride membrane filter and mini volume sampler. Endotoxin levels in the dust were determined by the Limulus Amebocyte Lysate Kinetic method. Interferon-γ production by peripheral blood mononuclear cells stimulated with concanavalin A was significantly lower in broilers or layers from the farms with higher endotoxin concentrations than the chickens from the farms with lower endotoxin levels. An opposite pattern was observed for plasma cortisol concentrations with higher cortisol levels found in chickens from the farms with higher endotoxin levels. When peripheral lymphocytes were examined, the percentage of CD3-Ia+ B cells was lower in layers from farms with higher endotoxin levels than those from locations with lower endotoxin levels. Overall, these results suggest a probable negative association between dust endotoxin levels and cell-mediated immunity in chickens. PMID:25549222

  20. Particulate matter from indoor environments of classroom induced higher cytotoxicity and leakiness in human microvascular endothelial cells in comparison with those collected from corridor.

    PubMed

    Chua, M L; Setyawati, M I; Li, H; Fang, C H Y; Gurusamy, S; Teoh, F T L; Leong, D T; George, S

    2017-05-01

    We investigated the physicochemical properties (size, shape, elemental composition, and endotoxin) of size resolved particulate matter (PM) collected from the indoor and corridor environments of classrooms. A comparative hazard profiling of these PM was conducted using human microvascular endothelial cells (HMVEC). Oxidative stress-dependent cytotoxicity responses were assessed using quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and high content screening (HCS), and disruption of monolayer cell integrity was assessed using fluorescence microscopy and transwell assay. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) analysis showed differences in the morphology and elemental composition of PM of different sizes and origins. While the total mass of PM collected from indoor environment was lower in comparison with those collected from the corridor, the endotoxin content was substantially higher in indoor PM (e.g., ninefold higher endotoxin level in indoor PM 8.1-20 ). The ability to induce oxidative stress-mediated cytotoxicity and leakiness in cell monolayer were higher for indoor PM compared to those collected from the corridor. In conclusion, this comparative analysis suggested that indoor PM is relatively more hazardous to the endothelial system possibly because of higher endotoxin content. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Allergens in School Settings: Results of Environmental Assessments in 3 City School Systems

    ERIC Educational Resources Information Center

    Abramson, Stuart L.; Turner-Henson, Anne; Anderson, Lise; Hemstreet, Mary P.; Bartholomew, L. Kay; Joseph, Christine L. M.; Tang, Shenghui; Tyrrell, Shellie; Clark, Noreen M.; Ownby, Dennis

    2006-01-01

    Environmental allergens are major triggers for pediatric asthma. While children's greatest exposure to indoor allergens is in the home, other public places where children spend a large amount of time, such as school and day care centers, may also be sources of significant allergen encounters. The purpose of this article is to describe schoolroom…

  2. Endotoxin in inner-city homes: associations with wheeze and eczema in early childhood.

    PubMed

    Perzanowski, Matthew S; Miller, Rachel L; Thorne, Peter S; Barr, R Graham; Divjan, Adnan; Sheares, Beverley J; Garfinkel, Robin S; Perera, Frederica P; Goldstein, Inge F; Chew, Ginger L

    2006-05-01

    An inverse association between domestic exposure to endotoxin and atopy in childhood has been observed. The relevance of this aspect of the hygiene hypothesis to US inner-city communities that have disproportionately high asthma prevalence has not been determined. To measure endotoxin in the dust from inner-city homes, evaluate associations between endotoxin and housing/lifestyle characteristics, and determine whether endotoxin exposure predicted wheeze, allergic rhinitis, and eczema over the first 3 years of life. As part of an ongoing prospective birth cohort study, children of Dominican and African-American mothers living in New York City underwent repeated questionnaire measures. Dust samples collected from bedroom floors at age 12 or 36 months were assayed for endotoxin. Among the samples collected from 301 participants' homes, the geometric mean endotoxin concentration (95% CI) was 75.9 EU/mg (66-87), and load was 3892 EU/m2 (3351-4522). Lower endotoxin concentrations were associated with wet mop cleaning and certain neighborhoods. Endotoxin concentration correlated weakly with cockroach (Bla g 2: r = 0.22, P < .001) and mouse (mouse urinary protein: r = 0.28; P < .001) allergens in the dust. Children in homes with higher endotoxin concentration were less likely to have eczema at age 1 year (odds ratio, 0.70 [0.53-0.93]) and more likely to wheeze at age 2 years (odds ratio, 1.34 [1.01-1.78]). These associations were stronger among children with a maternal history of asthma. Endotoxin levels in this inner-city community are similar to those in nonfarm homes elsewhere. In this community, domestic endotoxin exposure was inversely associated with eczema at age 1 year, but positively associated with wheeze at age 2 years. Endotoxin exposure in the inner-city community may be related to wheeze in the early life; however, given the inverse association seen with eczema, the long-term development of allergic disease is still in question.

  3. Differential effects of air conditioning type on residential endotoxin levels in a semi-arid climate.

    PubMed

    Johnston, J D; Kruman, B A; Nelson, M C; Merrill, R M; Graul, R J; Hoybjerg, T G; Tuttle, S C; Myers, S J; Cook, R B; Weber, K S

    2017-09-01

    Residential endotoxin exposure is associated with protective and pathogenic health outcomes. Evaporative coolers, an energy-efficient type of air conditioner used in dry climates, are a potential source of indoor endotoxins; however, this association is largely unstudied. We collected settled dust biannually from four locations in homes with evaporative coolers (n=18) and central air conditioners (n=22) in Utah County, Utah (USA), during winter (Jan-Apr) and summer (Aug-Sept), 2014. Dust samples (n=281) were analyzed by the Limulus amebocyte lysate test. Housing factors were measured by survey, and indoor temperature and relative humidity measures were collected during both seasons. Endotoxin concentrations (EU/mg) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons. Endotoxin surface loads (EU/m 2 ) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons and in upholstered furniture during winter. For the nine significant season-by-location comparisons, EU/mg and EU/m 2 were approximately three to six times greater in homes using evaporative coolers. A plausible explanation for these findings is that evaporative coolers serve as a reservoir and distribution system for Gram-negative bacteria or their cell wall components in homes. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Comparison of patterns of allergen sensitization among inner-city Hispanic and African American children with asthma.

    PubMed

    Rastogi, Deepa; Reddy, Mamta; Neugebauer, Richard

    2006-11-01

    Among Hispanics, the largest minority ethnic group in the United States, asthma prevalence is increasing, particularly in inner-city neighborhoods. Although allergen sensitization among asthmatic African Americans has been extensively studied, similar details are not available for Hispanic children. To examine patterns of allergen sensitization, including the association with illness severity, in asthmatic children overall and in Hispanic and African American children living in a socioeconomically disadvantaged area of New York City. A retrospective medical record review of asthmatic children attending a community hospital in the South Bronx area of New York City was performed. Information abstracted included demographics, asthma severity classification, reported exposures to indoor allergens, and results of allergy testing. Among 384 children in the analysis, 270 (70.3%) were Hispanic and 114 (29.7%) were African American. Sensitization to indoor and outdoor allergens, respectively, did not differ between Hispanic (58.5% and 27.0%) and African American (58.8% and 32.6%) children. Allergen sensitization exhibited a direct, significant association with asthma severity for indoor allergens for the 2 ethnic groups combined and for Hispanics separately but not between asthma severity and outdoor allergens (P < .01). No correlation was found between self-reported allergen exposure and sensitization. Patterns of allergen sensitization among inner-city Hispanic asthmatic children resemble those among African American children, a finding that is likely explained by the similarity in levels of environmental exposures. With the increasing prevalence of asthma among inner-city Hispanic children, skin testing should be used frequently for objective evaluation of asthma in this ethnic group.

  5. THE ALLERGENIC POTENTIAL OF INDOOR AIR FUNGAL CONTAMINANTS

    EPA Science Inventory

    ABSTRACT

    The indoor environment has increased in importance to children's health with children now spending more than 90% of their time indoors. Molds are an important component of this environment and have been associated with exacerbation of asthma. Their contribution t...

  6. Variability of Offending Allergens of Allergic Rhinitis According to Age: Optimization of Skin Prick Test Allergens

    PubMed Central

    Lee, Ji-Eun; Ahn, Jae-Chul; Han, Doo Hee; Kim, Dong-Young; Kim, Jung-Whun; Cho, Sang-Heon; Park, Heung-Woo

    2014-01-01

    Purpose This study evaluates offending allergens in patients with allergic rhinitis (AR) according to age that establish a minimal panel for skin prick test (SPT) allergens required to identify if a patient is sensitized. Methods We retrospectively analyzed SPT results according to age to determine the minimum test battery panel necessary to screen at least 93%-95% of AR patients. Allergic skin tests (common airborne indoor and outdoor allergens) were performed on 7,182 patients from January 2007 to June 2011. All patients were classified into 9 groups according to age; subsequently, we investigated offending allergens by age group. Results A total of 5,032 (70.1%) patients were found sensitized to at least one of the 55 aeroallergen extracts tested. The annual ranking of offending allergens was not significantly different from each other over the past 5 years. House dust mites (HDM) were the most prevalent allergens ranked from first to third for all 5 years. The allergens in the minimum test panel differed slightly among all age groups; in addition, the types of sensitized allergen sources were more diverse in the older versus younger age group. HDM covered a larger proportion of the sensitized allergens in the younger age group versus the older age group. Testing with 5 allergens (Dermatophagoides farinae, Tetranychus urticae, oak, mugwort and cockroach) adequately identified over 90% of the sensitized patients. Conclusions A SPT with around 5-7 allergens adequately detected most of the sensitization in the majority of the age groups in Korea. However, this study suggests that physicians perform the SPT with appropriately selected allergens in each age category for the screening of AR. PMID:24404393

  7. Variability of offending allergens of allergic rhinitis according to age: optimization of skin prick test allergens.

    PubMed

    Lee, Ji-Eun; Ahn, Jae-Chul; Han, Doo Hee; Kim, Dong-Young; Kim, Jung-Whun; Cho, Sang-Heon; Park, Heung-Woo; Rhee, Chae-Seo

    2014-01-01

    This study evaluates offending allergens in patients with allergic rhinitis (AR) according to age that establish a minimal panel for skin prick test (SPT) allergens required to identify if a patient is sensitized. We retrospectively analyzed SPT results according to age to determine the minimum test battery panel necessary to screen at least 93%-95% of AR patients. Allergic skin tests (common airborne indoor and outdoor allergens) were performed on 7,182 patients from January 2007 to June 2011. All patients were classified into 9 groups according to age; subsequently, we investigated offending allergens by age group. A total of 5,032 (70.1%) patients were found sensitized to at least one of the 55 aeroallergen extracts tested. The annual ranking of offending allergens was not significantly different from each other over the past 5 years. House dust mites (HDM) were the most prevalent allergens ranked from first to third for all 5 years. The allergens in the minimum test panel differed slightly among all age groups; in addition, the types of sensitized allergen sources were more diverse in the older versus younger age group. HDM covered a larger proportion of the sensitized allergens in the younger age group versus the older age group. Testing with 5 allergens (Dermatophagoides farinae, Tetranychus urticae, oak, mugwort and cockroach) adequately identified over 90% of the sensitized patients. A SPT with around 5-7 allergens adequately detected most of the sensitization in the majority of the age groups in Korea. However, this study suggests that physicians perform the SPT with appropriately selected allergens in each age category for the screening of AR.

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

    PubMed

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

    1998-10-01

    Studies of house dust mite allergen concentrations suggest large variations both within and between homes. It is likely that different household characteristics influence allergen levels in different locations within the house. To investigate household characteristics associated with higher concentrations of house dust mite allergen in a random sample of houses. Information on indoor environment was obtained from 158 adults aged 20-44. Dust samples were collected from their living room floor, bedroom floor and mattress. Concentrations of Der p 1, the major allergen from the house dust mite Dermatophagoides pteronyssinus, were measured by monoclonal antibody immunoassay. Associations between mite allergen concentrations and household characteristics were examined using censored-normal regression models. Factors that were related to Der p 1 (P

  9. Epizootiological characteristics of viable bacteria and fungi in indoor air from porcine, chicken, or bovine husbandry confinement buildings

    PubMed Central

    Roque, Katharine; Lim, Gyeong-Dong; Jo, Ji-Hoon; Shin, Kyung-Min; Song, Eun-Seob; Gautam, Ravi; Kim, Chang-Yul; Lee, Kyungsuk; Shin, Seungwon; Yoo, Han-Sang; Heo, Yong

    2016-01-01

    Microorganisms found in bioaerosols from animal confinement buildings not only foster the risk of spreading diseases among livestock buildings, but also pose health hazards to farm workers and nearby residents. This study identified the various microorganisms present in the air of swine, chicken, and cattle farms with different kinds of ventilation conditions in Korea. Microbial air samples were collected onto Petri dishes with bacterial or fungal growth media using a cascade impactor. Endotoxin levels in total dust were determined by the limulus amebocyte lysate kinetic QCL method. Prevalent Gram-positive bacteria were Staphylococcus (S.) lentus, S. chromogenes, Bacillus (B.) cereus, B. licheniformis, and Enterococcus faecalis, while the dominant fungi and Gram-negative bacteria were Candida albicans and Sphingomonas paucimobilis, respectively. Considering no significant relationship between the indoor dust endotoxin levels and the isolation of Gram-negative bacteria from the indoor air, monitoring the indoor airborne endotoxin level was found to be also critical for risk assessment on health for animals or workers. The present study confirms the importance of microbiological monitoring and control on animal husbandry indoor air to ensure animal and worker welfare. PMID:27456779

  10. Lead, Allergen, and Pesticide Levels in Licensed Child Care Centers in the United States

    EPA Science Inventory

    The First National Environmental Health Survey of Child Care Centers was conducted to provide information about lead, allergens, and pesticide levels in licensed U.S. child care centers. Lead levels were measured in settled dust, paint, and play area soil; indoor allergen levels ...

  11. PROTEOMIC ANALYSIS OF ALLERGENS FROM METARHIZIUM ANISOPLIAE

    EPA Science Inventory

    Introduction

    The goal of this project is the identification and characterization of allergens from the fungus Metarhizium anisopliae, using mass spectrometry (MS). The US EPA, under the "Children at Risk" program, is currently addressing the problem of indoor fungal bioaer...

  12. PROTEOMIC ANALYSIS OF ALLERGENS FROM METARHIZIUM ANISOPLIEA

    EPA Science Inventory

    The goal of this project is the identification and characterization of allergens from the fungus M. Anisopliae, using mass spectrometry (MS). The US EPA, under the "Children at Risk" program, is currently addressing the problem of indoor fungal bioaerosol contamination. One of ...

  13. Orthologous Allergens and Diagnostic Utility of Major Allergen Alt a 1

    PubMed Central

    Moreno, Antonio; Alcover, Javier; Rodríguez, David; Palacios, Ricardo; Martínez-Naves, Eduardo

    2016-01-01

    Purpose Hypersensitivity to fungi is associated with rhinoconjunctivitis and asthma. For some fungi, such as Alternaria alternata (A. alternata), the symptoms of asthma are persistent, increasing disease severity and the risk of fatal outcomes. There are a large number of species of fungi but knowledge of them remains limited. This, together with the difficulties in obtaining adequate standardized extracts, means that there remain significant challenges in the diagnosis and immunotherapy of allergy associated with fungi. The type of indoor fungi related to asthma/allergy varies according to geographic, climatic, and seasonal factors, making their study difficult. The aim of this study was to determine hypersensitivity to indoor fungi in a population from Cuenca, Spain. Methods Thirty-five patients with symptoms compatible with rhinitis or asthma who showed clear worsening of their symptoms in their homes or workplace were included. In vivo and in vitro tests were made with a battery of fungal allergens, including the species isolated in the home or workplace. Results Ulocladium botrytis (U. botrytis) and A. alternata were the most representative species as a source of home sensitization. These species showed very high concordance in skin tests, specific IgE, and histamine release. The allergen Alt a 1, which was recognized in all patients, was detected in A. alternata, U. botrytis, and Stemphylium botryosum (S. botryosum). Conclusions U. botrytis and A. alternata were the most representative species as a source of home sensitization. Alt a 1 was recognized in all patients and may be considered a non-species-specific allergen that could be used as a diagnostic source of sensitization to some species of the Pleosporaceae family. PMID:27334781

  14. Expression of an endotoxin-free S-layer/allergen fusion protein in gram-positive Bacillus subtilis 1012 for the potential application as vaccines for immunotherapy of atopic allergy

    PubMed Central

    2011-01-01

    Background Genetic fusion of the major birch pollen allergen (Bet v1) to bacterial surface-(S)-layer proteins resulted in recombinant proteins exhibiting reduced allergenicity as well as immunomodulatory capacity. Thus, S-layer/allergen fusion proteins were considered as suitable carriers for new immunotherapeutical vaccines for treatment of Type I hypersensitivity. Up to now, endotoxin contamination of the fusion protein which occurred after isolation from the gram-negative expression host E. coli had to be removed by an expensive and time consuming procedure. In the present study, in order to achieve expression of pyrogen-free, recombinant S-layer/allergen fusion protein and to study the secretion of a protein capable to self-assemble, the S-layer/allergen fusion protein rSbpA/Bet v1 was produced in the gram-positive organism Bacillus subtilis 1012. Results The chimaeric gene encoding the S-layer protein SbpA of Lysinibacillus sphaericus CCM 2177 as well as Bet v1 was cloned and expressed in B. subtilis 1012. For that purpose, the E. coli-B. subtilis shuttle vectors pHT01 for expression in the B. subtilis cytoplasm and pHT43 for secretion of the recombinant fusion protein into the culture medium were used. As shown by western blot analysis, immediately after induction of expression, B. subtilis 1012 was able to secret rSbpA/Bet v1 mediated by the signal peptide amyQ of Bacillus amyloliquefaciens. Electron microscopical investigation of the culture medium revealed that the secreted fusion protein was able to form self-assembly products in suspension but did not recrystallize on the surface of the B. subtilis cells. The specific binding mechanism between the N-terminus of the S-layer protein and a secondary cell wall polymer (SCWP), located in the peptidoglycan-containing sacculi of Ly. sphaericus CCM 2177, could be used for isolation and purification of the secreted fusion protein from the culture medium. Immune reactivity of rSbpA/Bet v1 could be demonstrated in

  15. Increased Levels of Markers of Microbial Exposure in Homes with Indoor Storage of Organic Household Waste

    PubMed Central

    Wouters, Inge M.; Douwes, Jeroen; Doekes, Gert; Thorne, Peter S.; Brunekreef, Bert; Heederik, Dick J. J.

    2000-01-01

    As part of environmental management policies in Europe, separate collection of organic household waste and nonorganic household waste has become increasingly common. As waste is often stored indoors, this policy might increase microbial exposure in the home environment. In this study we evaluated the association between indoor storage of organic waste and levels of microbial agents in house dust. The levels of bacterial endotoxins, mold β(1→3)-glucans, and fungal extracullar polysaccharides (EPS) of Aspergillus and Penicillium species were determined in house dust extracts as markers of microbial exposure. House dust samples were collected in 99 homes in The Netherlands selected on the basis of whether separated organic waste was present in the house. In homes in which separated organic waste was stored indoors for 1 week or more the levels of endotoxin, EPS, and glucan were 3.2-, 7.6-, and 4.6-fold higher, respectively (all P < 0.05), on both living room and kitchen floors than the levels in homes in which only nonorganic residual waste was stored indoors. Increased levels of endotoxin and EPS were observed, 2.6- and 2.1-fold (P < 0.1), respectively, when separated organic waste was stored indoors for 1 week or less, whereas storage of nonseparated waste indoors had no effect on microbial agent levels (P > 0.2). The presence of textile floor covering was another major determinant of microbial levels (P < 0.05). Our results indicate that increased microbial contaminant levels in homes are associated with indoor storage of separated organic waste. These increased levels might increase the risk of bioaerosol-related respiratory symptoms in susceptible people. PMID:10653727

  16. The association between endotoxin and beta-(1 → 3)-D-glucan in house dust with asthma severity among schoolchildren.

    PubMed

    Oluwole, Oluwafemi; Rennie, Donna C; Senthilselvan, Ambikaipakan; Dyck, Roland; Afanasieva, Anna; Kirychuk, Shelley; Katselis, George; Lawson, Joshua A

    2018-05-01

    Asthma severity can be affected by microbial exposures. However, less is known about the specific indoor agents aggravating the disease in children. We examined the associations between indoor endotoxin and beta-(1 → 3)-D-glucan exposures and asthma severity in children with asthma. A clinical cross-sectional study of schoolchildren (aged 7-17 years) was conducted in the province of Saskatchewan, Canada. Children with asthma (n = 116) were identified from 335 participants using a combination of survey responses and objective clinical assessments. We then ascertained asthma severity based on recommended guidelines (continuous daytime asthma symptoms, frequent nighttime asthma symptoms, and ≤ 60% predicted FEV 1 ). Levels of indoor endotoxin and beta-(1 → 3)-D-glucan were measured in dust samples obtained from play area floors and child's mattresses. The study population of 116 children with asthma was comprised of 75.9% mild asthma and 24.1% moderate/severe asthma. Higher mattress endotoxin concentration was associated with increased odds of moderate/severe asthma [adjusted odds ratio (aOR) = 11.40, 95% confidence interval (CI): 1.45-89.43] while higher beta-(1 → 3)-D-glucan concentration (aOR = 0.16, 95% CI: 0.03-0.89) and load (aOR = 0.10, 95% CI: 0.02-0.72) in play areas were inversely associated with moderate/severe asthma. Furthermore, higher mattress endotoxin concentration was associated with lower FVC (p = 0.01) and FEV 1 (p = 0.03). These associations were not seen for beta-(1 → 3)-D-glucan. Our results showed differential effects of microbial exposures on childhood asthma severity and further highlight domestic endotoxin exposure effects on respiratory health outcomes in children with asthma. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Indoor Air Quality and Disease

    EPA Science Inventory

    Concern over the quality of indoor (i.e., residential) as well as outdoor (i.e., environmental) air is increasing. Accordingly, owners of companion animals may approach their veterinarian about the potential for airborne irritants, allergens, pollutants, or infectious agents to n...

  18. Indirect health effects of relative humidity in indoor environments.

    PubMed Central

    Arundel, A V; Sterling, E M; Biggin, J H; Sterling, T D

    1986-01-01

    A review of the health effects of relative humidity in indoor environments suggests that relative humidity can affect the incidence of respiratory infections and allergies. Experimental studies on airborne-transmitted infectious bacteria and viruses have shown that the survival or infectivity of these organisms is minimized by exposure to relative humidities between 40 and 70%. Nine epidemiological studies examined the relationship between the number of respiratory infections or absenteeism and the relative humidity of the office, residence, or school. The incidence of absenteeism or respiratory infections was found to be lower among people working or living in environments with mid-range versus low or high relative humidities. The indoor size of allergenic mite and fungal populations is directly dependent upon the relative humidity. Mite populations are minimized when the relative humidity is below 50% and reach a maximum size at 80% relative humidity. Most species of fungi cannot grow unless the relative humidity exceeds 60%. Relative humidity also affects the rate of offgassing of formaldehyde from indoor building materials, the rate of formation of acids and salts from sulfur and nitrogen dioxide, and the rate of formation of ozone. The influence of relative humidity on the abundance of allergens, pathogens, and noxious chemicals suggests that indoor relative humidity levels should be considered as a factor of indoor air quality. The majority of adverse health effects caused by relative humidity would be minimized by maintaining indoor levels between 40 and 60%. This would require humidification during winter in areas with cold winter climates. Humidification should preferably use evaporative or steam humidifiers, as cool mist humidifiers can disseminate aerosols contaminated with allergens. PMID:3709462

  19. Mold Allergens in Respiratory Allergy: From Structure to Therapy

    PubMed Central

    Twaroch, Teresa E; Curin, Mirela; Swoboda, Ines

    2015-01-01

    Allergic reactions to fungi were described 300 years ago, but the importance of allergy to fungi has been underestimated for a long time. Allergens from fungi mainly cause respiratory and skin symptoms in sensitized patients. In this review, we will focus on fungi and fungal allergens involved in respiratory forms of allergy, such as allergic rhinitis and asthma. Fungi can act as indoor and outdoor respiratory allergen sources, and depending on climate conditions, the rates of sensitization in individuals attending allergy clinics range from 5% to 20%. Due to the poor quality of natural fungal allergen extracts, diagnosis of fungal allergy is hampered, and allergen-specific immunotherapy is rarely given. Several factors are responsible for the poor quality of natural fungal extracts, among which the influence of culture conditions on allergen contents. However, molecular cloning techniques have allowed us to isolate DNAs coding for fungal allergens and to produce a continuously growing panel of recombinant allergens for the diagnosis of fungal allergy. Moreover, technologies are now available for the preparation of recombinant and synthetic fungal allergen derivatives which can be used to develop safe vaccines for the treatment of fungal allergy. PMID:25840710

  20. A clinical study of airborne allergens in the United Arab Emirates.

    PubMed

    Lestringant, G G; Bener, A; Frossard, P M; Abdulkhalik, S; Bouix, G

    1999-10-01

    In the past 25 years the United Arab Emirates (UAE) have experienced a socioeconomic boom. The once nomadic Bedouin population of Al Ain, in the emirate of Abu Dhabi, now lives in modern air-conditioned accommodation, and huge desalination plants have allowed afforestation and farming. To evidence responsible airborne allergens in an UAE population. 263 UAE Nationals who attended Tawam Hospital (Al Ain, UAE) with a respiratory disease suspected of being of allergic origin, were submitted to SPT and RAST. The choice of pollinic allergens was made in accordance with the local flora and market availability. All patients were SPTed with at least the same battery of 15 pollinic and indoor allergens. Most patients were submitted to at least 4 RAST, viz Cynodon dactylon, Salsola kali, Prosopis juliflora and Dermatophagoides pteronyssinus. 71.8% patients were positive for at least one allergen. Pollen accounted for 61.6% of positive patients, with 45.2% positive to chenopodiaceae, 33% to gramineae and 23.5% to P. juliflora. Indoor allergens were positive in 30.4% of patients with 17.9% positive to D. pteronyssinus and D. farinae, 11% to Blatella germanica, 8.3% to Cat fur, 4.9% to Goat hair, 0.7% to Rat hair and Mouse hair and 1.5% to Candida albicans. Pollen was the prominent allergen. There is room, however, for further epidemiological studies possibly with new extracts and RAST specifically designed after the species of the Gulf region.

  1. SUBCHRONIC ENDOTOXIN INHALATION CAUSES CHRONIC AIRWAY DISEASE IN ENDOTOXIN-SENSITIVE BUT NOT ENDOTOXIN-RESISTANT MICE

    EPA Science Inventory

    SUBCHRONIC ENDOTOXIN INHALATION CAUSES CHRONIC AIRWAY DISEASE IN ENDOTOXIN-SENSITIVE BUT NOT ENDOTOXIN-RESISTANT MICE. D. M. Brass, J. D. Savov, *S. H. Gavett, ?C. George, D. A. Schwartz. Duke Univ Medical Center Durham, NC, *U.S. E.P.A. Research Triangle Park, NC, ?Univ of Iowa,...

  2. Current trends in endotoxin detection and analysis of endotoxin-protein interactions.

    PubMed

    Dullah, Elvina Clarie; Ongkudon, Clarence M

    2017-03-01

    Endotoxin is a type of pyrogen that can be found in Gram-negative bacteria. Endotoxin can form a stable interaction with other biomolecules thus making its removal difficult especially during the production of biopharmaceutical drugs. The prevention of endotoxins from contaminating biopharmaceutical products is paramount as endotoxin contamination, even in small quantities, can result in fever, inflammation, sepsis, tissue damage and even lead to death. Highly sensitive and accurate detection of endotoxins are keys in the development of biopharmaceutical products derived from Gram-negative bacteria. It will facilitate the study of the intermolecular interaction of an endotoxin with other biomolecules, hence the selection of appropriate endotoxin removal strategies. Currently, most researchers rely on the conventional LAL-based endotoxin detection method. However, new methods have been and are being developed to overcome the problems associated with the LAL-based method. This review paper highlights the current research trends in endotoxin detection from conventional methods to newly developed biosensors. Additionally, it also provides an overview of the use of electron microscopy, dynamic light scattering (DLS), fluorescence resonance energy transfer (FRET) and docking programs in the endotoxin-protein analysis.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-07-01

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

  5. Characterization of the bacterial and fungal microbiome in indoor dust and outdoor air samples: a pilot study.

    PubMed

    Hanson, Blake; Zhou, Yanjiao; Bautista, Eddy J; Urch, Bruce; Speck, Mary; Silverman, Frances; Muilenberg, Michael; Phipatanakul, Wanda; Weinstock, George; Sodergren, Erica; Gold, Diane R; Sordillo, Joanne E

    2016-06-15

    Environmental microbes have been associated with both protective and adverse health effects in children and adults. Epidemiological studies often rely on broad biomarkers of microbial exposure (i.e. endotoxin, 1 → 3-beta-d-glucan), but fail to identify the taxonomic composition of the microbial community. Our aim was to characterize the bacterial and fungal microbiome in different types of environmental samples collected in studies of human health effects. We determined the composition of microbial communities present in home, school and outdoor air samples by amplifying and sequencing regions of rRNA genes from bacteria (16S) and fungi (18S and ITS). Samples for this pilot study included indoor settled dust (from both a Boston area birth cohort study on Home Allergens and Asthma (HAA) (n = 12) and a study of school exposures and asthma symptoms (SICAS) (n = 1)), as well as fine and coarse concentrated outdoor ambient particulate (CAP) samples (n = 9). Sequencing of amplified 16S, 18S, and ITS regions was performed on the Roche-454 Life Sciences Titanium pyrosequencing platform. Indoor dust samples were dominated by Gram-positive bacteria (Firmicutes and Actinobacteria); the most abundant bacterial genera were those related to human flora (Streptococcus, Staphylococcus, Corynebacterium and Lactobacillus). Outdoor CAPs were dominated by Gram-negative Proteobacteria from water and soil sources, in particular the genera Acidovorax, and Brevundimonas (which were present at very low levels or entirely absent in indoor dust). Phylum-level fungal distributions identified by 18S or ITS regions showed very similar findings: a predominance of Ascomycota in indoor dust and Basidiomycota in outdoor CAPs. ITS sequencing of fungal genera in indoor dust showed significant proportions of Aureobasidium and Leptosphaerulina along with some contribution from Cryptococcus, Epicoccum, Aspergillus and the human commensal Malassezia. ITS sequencing detected more than 70 fungal genera

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

    PubMed

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

    2007-08-01

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

  7. Characterisation of allergens and airborne fungi in low and middle-income homes of primary school children in Durban, South Africa

    PubMed Central

    Jafta, Nkosana; Batterman, Stuart A.; Gqaleni, Nceba; Naidoo, Rajen N.; Robins, Thomas G.

    2012-01-01

    The South Durban Health Study is a population-based study that examined the relationship between exposure to ambient air pollutants and respiratory disease among school children with high prevalence of asthma who resided in two purposely-selected communities in north and south Durban, KwaZulu-Natal, South Africa. From these participants, a subgroup of 135 families was selected for investigation of household characteristics potentially related to respiratory health. In these households, a walkthrough investigation was conducted, and settled dust and air samples were collected for allergen and fungal measurements using standardised techniques. Asp f1 allergen was detected in all homes, and Bla g1 allergen was detected in half of the homes. House dust allergens, Der f1 and Der p1 exceeded concentrations associated with risk of sensitization and exacerbation of asthma in 3 and 13%, respectively, of the sampled homes, while Bla g1 exceeded guidance values in 13% of the homes. Although airborne fungal concentrations in sleep areas and indoors were lower than outdoor concentrations, they exceeded 1000 CFU/m3 in 29% of the homes. Multivariate analyses identified several home characteristics that were predictors of airborne fungal concentrations, including moisture, ventilation, floor type and bedding type. Airborne fungal concentrations were similar indoors and outdoors, which likely reduced the significance of housing and indoor factors as determinants of indoor concentrations. Conclusion Allergen concentrations were highly variable in homes, and a portion of the variability can be attributed to easily-recognised conditions. PMID:22674665

  8. Factors influencing the quality of Myrmecia pilosula (Jack Jumper) ant venom for use in in vitro and in vivo diagnoses of allergen sensitization and in allergen immunotherapy.

    PubMed

    Wanandy, T; Dwyer, H E; McLean, L; Davies, N W; Nichols, D; Gueven, N; Brown, S G A; Wiese, M D

    2017-11-01

    Allergen immunotherapy uses pharmaceutical preparations derived from naturally occurring source materials, which contain water-soluble allergenic components responsible for allergic reactions. The success of in vivo and in vitro diagnoses in allergen sensitization and allergen immunotherapy largely depends on the quality, composition and uniformity of allergenic materials used to produce the active ingredients, and the formulation employed to prepare finished products. We aimed to examine the factors influencing batch-to-batch consistency of Jack Jumper (Myrmecia pilosula) ant venom (JJAV) in the form of active pharmaceutical ingredient (AI) and informed whether factors such as temperature, artificial light and container materials influence the quality of JJAV AIs. We also aimed to establish handling and storage requirements of JJAV AIs to ensure preservation of allergenic activities during usage in the diagnosis of allergen sensitization and in allergen immunotherapy. The quality and consistency of JJAV AIs were analysed using a combination of bicinchoninic acid assay for total protein quantification, HPLC-UV for JJAV allergen peptides quantification, ELISA inhibition for total allergenic potency, SDS-PAGE, AU-PAGE and immunoblot for qualitative assessment of JJAV components, and Limulus Amebocyte Lysate assay for the quantification of endotoxin concentration. API-ZYM and Zymogram assays were used to probe the presence of enzymatic activities in JJAV. Pharmaceutical-grade JJAV for allergen immunotherapy has good batch-to-batch consistency. Temporary storage at 4°C and light exposure do not affect the quality of JJAV. Exposure to temperature above 40°C degrades high MW allergens in JJAV. Vials containing JJAV must be stored frozen and in upright position during long-term storage. We have identified factors, which can influence the quality and consistency of JJAV AIs, and provided a framework for appropriate handling, transporting and storage of JJAV to be used

  9. Animal Allergens and Their Presence in the Environment

    PubMed Central

    Zahradnik, Eva; Raulf, Monika

    2014-01-01

    Exposure to animal allergens is a major risk factor for sensitization and allergic diseases. Besides mites and cockroaches, the most important animal allergens are derived from mammals. Cat and dog allergies affect the general population; whereas, allergies to rodents or cattle is an occupational problem. Exposure to animal allergens is not limited to direct contact to animals. Based on their aerodynamic properties, mammalian allergens easily become airborne, attach to clothing and hair, and can be spread from one environment to another. For example, the major cat allergen Fel d 1 was frequently found in homes without pets and in public buildings, including schools, day-care centers, and hospitals. Allergen concentrations in a particular environment showed high variability depending on numerous factors. Assessment of allergen exposure levels is a stepwise process that involves dust collection, allergen quantification, and data analysis. Whereas a number of different dust sampling strategies are used, ELISA assays have prevailed in the last years as the standard technique for quantification of allergen concentrations. This review focuses on allergens arising from domestic, farm, and laboratory animals and describes the ubiquity of mammalian allergens in the human environment. It includes an overview of exposure assessment studies carried out in different indoor settings (homes, schools, workplaces) using numerous sampling and analytical methods and summarizes significant factors influencing exposure levels. However, methodological differences among studies have contributed to the variability of the findings and make comparisons between studies difficult. Therefore, a general standardization of methods is needed and recommended. PMID:24624129

  10. Irritants and allergens at school in relation to furnishings and cleaning.

    PubMed

    Smedje, G; Norbäck, D

    2001-06-01

    In order to study the influence of furnishings and cleaning on the indoor air quality at school, 181 randomly chosen classrooms were investigated. The amounts of open shelves, textiles and other fittings were noted, data were gathered on cleaning routines, and a number of pollutants were measured in the classrooms. In classrooms with more fabrics there was more settled dust and the concentration of formaldehyde was higher. Classrooms with more open shelves had more formaldehyde, and more pet allergens in settled dust, and classrooms with a white board, instead of a chalk board, were less dusty. Classrooms mainly cleaned through wet mopping had more airborne viable bacteria but less settled dust than classrooms mainly cleaned by dry methods. In rooms where the desks and curtains were more often cleaned, the concentrations of cat and dog allergen in settled dust were lower. It is concluded that furnishings and textiles in the classroom act as significant reservoirs of irritants and allergens and have an impact on the indoor air quality at school.

  11. Endotoxins in Environmental and Clinical Samples Assessed by GC-Tandem MS

    NASA Astrophysics Data System (ADS)

    Szponar, Bogumila

    Bacteria appeared on the Earth millions years before us and human evolution was triggered by the constant presence of pathogenic and symbiotic microorganisms in our surroundings. Interplay occurred between higher organism and microbial consortia residing in the host organs and on the epithelial surfaces; another natural space of bacteria-human interaction is the indoor environment where we spend the majority of our lifetime. Indoor microbial exposure affects our well-being and can result in respiratory symptoms, such as allergies and asthma, since both dead and live microorganisms and their cell constituents, including lipopolysaccharides (LPS, endotoxins), interact with our immune system. Thus, there is a demand for robust tools for qualitative and quantitative determination of the microbial communities that we are exposed to.

  12. Allergen Avoidance in Allergic Asthma

    PubMed Central

    Cipriani, Francesca; Calamelli, Elisabetta; Ricci, Giampaolo

    2017-01-01

    Allergic asthma is the most frequent disease among the chronic respiratory disorders in pediatric age with an important social impact. In the last years, many efforts have been made to identify effective preventive approaches to get a better control of symptoms and to obtain the best future outcomes for the patients. In patients with allergic asthma triggered by the exposure to indoor allergens, the avoidance is the first intervention to prevent the appearance or the worsening of bronchial symptoms. This review article summarized the most recent evidence from literature about the efficacy of specific control interventions for the most important allergens. Even if a wide spectrum of interventions has been suggested and may help to reduce exposure to trigger allergy for sensitized patients suffering from respiratory allergy, evidence supporting the efficacy of these approaches is still weak and subject of controversy. However, the exposure control to specific airborne allergens is still widely recommended and may be effective as part of a holistic approach to reduce the severity of allergic respiratory symptoms in sensitized individuals. PMID:28540285

  13. Predictors and respiratory depositions of airborne endotoxin in homes using biomass fuels and LPG gas for cooking

    PubMed Central

    Padhi, Bijaya Kumar; Adhikari, Atin; Satapathy, Prakasini; Patra, Alok Kumar; Chandel, Dinesh; Panigrahi, Pinaki

    2016-01-01

    Recent studies have highlighted presence of endotoxin in indoor air and its role in respiratory morbidities. Burning of household fuels including unprocessed wood and dried animal dung could be a major source of endotoxin in homes. We measured endotoxin levels in different size fractions of airborne particles (PM10, PM2.5, and PM1), and estimated the deposition of particle-bound endotoxin in the respiratory tract. The study was carried out in homes burning solid biomass fuel (n = 35) and LPG (n = 35). Sample filters were analyzed for endotoxin and organic carbon (OC) content. Household characteristics including temperature, relative humidity, and carbon dioxide levels were also recorded. Multivariate regression models were used to estimate the contributing factors for airborne endotoxin. Respiratory deposition doses were calculated using a computer-based model. We found a higher endotoxin concentration in PM2.5 fractions of the particle in both LPG (median: 110, interquartile range, (IQR): 100-120 EU/m3) and biomass (median: 350, IQR: 315-430 EU/m3) burning homes. In the multivariate-adjusted model, burning of solid biomass fuel (β: 67; 95%CI: 10.5-124) emerged as the most significant predictor followed by OC (β: 4.7; 95%CI: 2.7-6.8), RH (β: 1.6; 95%CI: 0.76-2.4) and PM2.5 (β: 0.45; 95%CI: 0.11-0.78) for airborne endotoxin (p < 0.05). We also observed an interaction between PM organic carbon content and household fuel in predicting the endotoxin levels. The model calculations showed that in biomass burning homes, total endotoxin deposition was higher among infants (59%) than in adult males (47%), of which at least 10% of inhaled endotoxin is deposited in the alveolar region of the lung. These results indicate that fine particles are significant contributors to the deposition of endotoxin in the alveolar region of the lung. Considering the paramount role of endotoxin exposure, and the source and timing of exposure on respiratory health, additional studies are

  14. Predictors and respiratory depositions of airborne endotoxin in homes using biomass fuels and LPG gas for cooking.

    PubMed

    Padhi, Bijaya K; Adhikari, Atin; Satapathy, Prakasini; Patra, Alok K; Chandel, Dinesh; Panigrahi, Pinaki

    2017-01-01

    Recent studies have highlighted the presence of endotoxin in indoor air and its role in respiratory morbidities. Burning of household fuels including unprocessed wood and dried animal dung could be a major source of endotoxin in homes. We measured endotoxin levels in different size fractions of airborne particles (PM10, PM2.5, and PM1), and estimated the deposition of particle-bound endotoxin in the respiratory tract. The study was carried out in homes burning solid biomass fuel (n=35) and LPG (n=35). Sample filters were analyzed for endotoxin and organic carbon (OC) content. Household characteristics including temperature, relative humidity, and carbon dioxide levels were also recorded. Multivariate regression models were used to estimate the contributing factors for airborne endotoxin. Respiratory deposition doses were calculated using a computer-based model. We found a higher endotoxin concentration in PM2.5 fractions of the particle in both LPG (median: 110, interquartile range (IQR) 100-120 EU/m 3 ) and biomass (median: 350, IQR: 315-430 EU/m 3 ) burning homes. In the multivariate-adjusted model, burning of solid biomass fuel (β: 67; 95% CI: 10.5-124) emerged as the most significant predictor followed by OC (β: 4.7; 95% CI: 2.7-6.8), RH (β: 1.6; 95% CI: 0.76-2.4), and PM2.5 (β: 0.45; 95% CI: 0.11-0.78) for airborne endotoxin (P<0.05). We also observed an interaction between PM organic carbon content and household fuel in predicting the endotoxin levels. The model calculations showed that in biomass burning homes, total endotoxin deposition was higher among infants (59%) than in adult males (47%), of which at least 10% of inhaled endotoxin is deposited in the alveolar region of the lung. These results indicate that fine particles are significant contributors to the deposition of endotoxin in the alveolar region of the lung. Considering the paramount role of endotoxin exposure, and the source and timing of exposure on respiratory health, additional

  15. Biosensor of endotoxin and sepsis

    NASA Astrophysics Data System (ADS)

    Shao, Yang; Wang, Xiang; Wu, Xi; Gao, Wei; He, Qing-hua; Cai, Shaoxi

    2001-09-01

    To investigate the relation between biosensor of endotoxin and endotoxin of plasma in sepsis. Method: biosensor of endotoxin was designed with technology of quartz crystal microbalance bioaffinity sensor ligand of endotoxin were immobilized by protein A conjugate. When a sample soliton of plasma containing endotoxin 0.01, 0.03, 0.06, 0.1, 0.5, 1.0Eu, treated with perchloric acid and injected into slot of quartz crystal surface respectively, the ligand was released from the surface of quartz crystal to form a more stable complex with endotoxin in solution. The endotoxin concentration corresponded to the weight change on the crystal surface, and caused change of frequency that occurred when desorbed. The result was biosensor of endotoxin might detect endotoxin of plasma in sepsis, measurements range between 0.05Eu and 0.5Eu in the stop flow mode, measurement range between 0.1Eu and 1Eu in the flow mode. The sensor of endotoxin could detect the endotoxin of plasm rapidly, and use for detection sepsis in clinically.

  16. Monitoring total endotoxin and (1 --> 3)-beta-D-glucan at the air exhaust of concentrated animal feeding operations.

    PubMed

    Yang, Xufei; Wang, Xinlei; Zhang, Yuanhui; Lee, Jongmin; Su, Jingwei; Gates, Richard S

    2013-10-01

    Mitigation of bioaerosol emissions from concentrated animal feeding operations (CAFOs) demands knowledge of bioaerosol concentrations feeding into an end-of-pipe air treatment process. The aim of this preliminary study was to measure total endotoxin and (1 --> 3)-beta-glucan concentrations at the air exhaust of 18 commercial CAFOs and to examine their variability with animal operation type (swine farrowing, swine gestation, swine weaning, swine finishing, manure belt laying hen, and tom turkey) and season (cold, mild, and hot). The measured airborne concentrations of total endotoxin ranged from 98 to 23,157 endotoxin units (EU)/m3, and the airborne concentrations of total (1 --> 3)-beta-D-glucan ranged from 2.4 to 537.9 ng/m3. Animal operation type in this study had a significant effect on airborne concentrations of total endotoxin and (1 --> 3)-beta-D-glucan but no significant effect on their concentrations in total suspended particulate (TSP). Both endotoxin and (1 --> 3)-beta-D-glucan attained their highest airborne concentrations in visited tom turkey buildings. Comparatively, season had no significant effect on airborne concentrations of total endotoxin or (1 --> 3)-beta-D-glucan. Endotoxin and (1 --> 3)-beta-glucan concentrations in TSP dust appeared to increase as the weather became warmer, and this seasonal effect was significant in swine buildings. Elevated indoor temperatures in the hot season were considered to facilitate the growth and propagation of bacteria and fungi, thus leading to higher biocomponent concentrations in TSP.

  17. [Viable allergenic fungi in a documentary deposit of the National Archive of Cuba].

    PubMed

    Molina-Veloso, Alian; Borrego-Alonso, Sofía F

    2017-01-01

    Intense and persistent exposure to indoor-air biological agents has been associated with the appearance of allergic diseases. Archives and libraries Indoor environments in tropical countries are an important reservoir of fungal propagules. To evaluate the degree of air pollution with allergenic fungi in a repository of frequently-manipulated documents. Air sampling was performed by two methods: active (biocollector) and passive (sedimentation plate). Fungi were taxonomically identified, and spores were measured to determine their penetrability in the human respiratory tract, and its impact on episodes of allergy. In terms of concentration and diversity, the local environment behaved as a fungal propagule reservoir, which showed that there is significant health risk for the staff that manipulates the documents. Some spores were shown to be able to reach the lower respiratory tract when inhaled, which increases their allergenic and pathogenic potential. Aspergillus, Cladosporium, Penicillium and Alternaria, which are referred to as highly allergenic fungi, were prevalent. Aerobiological studies are a valuable tool for the treatment of patients with allergy to fungi and other disorders they produce.

  18. Association of Roadway Proximity with Indoor Air Pollution in a Peri-Urban Community in Lima, Peru

    PubMed Central

    Underhill, Lindsay J.; Bose, Sonali; Williams, D’Ann L.; Romero, Karina M.; Malpartida, Gary; Breysse, Patrick N.; Klasen, Elizabeth M.; Combe, Juan M.; Checkley, William; Hansel, Nadia N.

    2015-01-01

    The influence of traffic-related air pollution on indoor residential exposure is not well characterized in homes with high natural ventilation in low-income countries. Additionally, domestic allergen exposure is unknown in such populations. We conducted a pilot study of 25 homes in peri-urban Lima, Peru to estimate the effects of roadway proximity and season on residential concentrations. Indoor and outdoor concentrations of particulate matter (PM2.5), nitrogen dioxide (NO2), and black carbon (BC) were measured during two seasons, and allergens were measured in bedroom dust. Allergen levels were highest for dust mite and mouse allergens, with concentrations above clinically relevant thresholds in over a quarter and half of all homes, respectively. Mean indoor and outdoor pollutant concentrations were similar (PM2.5: 20.0 vs. 16.9 μg/m3, BC: 7.6 vs. 8.1 μg/m3, NO2: 7.3 vs. 7.5 ppb), and tended to be higher in the summer compared to the winter. Road proximity was significantly correlated with overall concentrations of outdoor PM2.5 (rs = −0.42, p = 0.01) and NO2 (rs = −0.36, p = 0.03), and outdoor BC concentrations in the winter (rs = −0.51, p = 0.03). Our results suggest that outdoor-sourced pollutants significantly influence indoor air quality in peri-urban Peruvian communities, and homes closer to roadways are particularly vulnerable. PMID:26516875

  19. Characterization of the bacterial and fungal microbiome in indoor dust and outdoor air samples: a pilot study†

    PubMed Central

    Hanson, Blake; Zhou, Yanjiao; Bautista, Eddy J.; Urch, Bruce; Speck, Mary; Silverman, Frances; Muilenberg, Michael; Phipatanakul, Wanda; Weinstock, George; Sodergren, Erica; Gold, Diane R.; Sordillo, Joanne E.

    2016-01-01

    Environmental microbes have been associated with both protective and adverse health effects in children and adults. Epidemiological studies often rely on broad biomarkers of microbial exposure (i.e. endotoxin, 1→3, Beta-D glucan), but fail to identify the taxonomic composition of the microbial community. Our aim was to characterize the bacterial and fungal microbiome in different types of environmental samples collected in studies of human health effects. We determined the composition of microbial communities present in home, school and outdoor air samples by amplifying and sequencing regions of rRNA genes from bacteria (16S) and fungi (18S and ITS). Samples for this pilot study included indoor settled dust (from both a Boston area birth cohort study on Home Allergens and Asthma (HAA)(n=12) and a study of school exposures and asthma symptoms (SICAS) (n=1)), as well as fine and coarse concentrated outdoor ambient particulate (CAP) samples (n=9). Sequencing of amplified 16S, 18S, and ITS regions was performed on the Roche-454 Life Sciences Titanium pyrosequencing platform. Indoor dust samples were dominated by gram-positive bacteria (Firmicutes and Actinobacteria); the most abundant bacterial genera were those related to human flora (Streptococcus, Staphylococcus, Corynebacterium and Lactobacillus). Outdoor CAPs were dominated by gram-negative Proteobacteria from water and soil sources, in particular the genera Acidovorax, and Brevundimonas (which were present at very low levels or entirely absent in indoor dust). Phylum-level fungal distributions identified by 18S or ITS regions showed very similar findings: a predominance of Ascomycota in indoor dust and Basidiomycota in outdoor CAPs. ITS sequencing of fungal genera in indoor dust showed significant proportions of Aureobasidium and Leptosphaerulina along with some contribution from Cryptococcus, Epicoccum, Aspergillus and the human commensal Malassezia. ITS sequencing detected an additional 70 fungal genera in

  20. An assessment of indoor air quality in recent Mexican immigrant housing in Commerce City, Colorado

    NASA Astrophysics Data System (ADS)

    Miller, Shelly L.; Scaramella, Peter; Campe, Joseph; Goss, Cynthia W.; Diaz-Castillo, Sandra; Hendrikson, Ed; DiGuiseppi, Carolyn; Litt, Jill

    An indoor air quality assessment was conducted on 100 homes of recent Mexican immigrants in Commerce City, Colorado, an urban industrial community north of Denver. Head of households were administered a family health survey, filled out an activity diary, and participated in a home inspection. Carbon monoxide (CO) and carbon dioxide (CO 2) were measured for 24 h inside the main living area and outside of the homes. Harvard Impactors were used to collect 24-h samples of PM 2.5 at the same locations for gravimetric analysis. Dust samples were collected by vacuuming carpeting and flooring at four locations within the home and analyzed by ELISA for seven allergens. Mean indoor and outdoor PM 2.5 levels were 27.2 and 8.5 μg m -3, respectively. Indoor PM 2.5 and CO 2 were elevated in homes for which the number of hours with door/window open was zero compared to homes in which the number of hours was high (>15 h). Indoor PM 2.5 levels did not correlate with outdoor levels and tended to increase with number of inhabitants, and results indicate that the source of indoor particles were occupants and their activities, excluding smoking and cooking. Mean indoor CO 2 and CO levels were 1170 and 2.4 ppm, respectively. Carbon monoxide was higher than the 24-h National Ambient Air Quality Standard in 3 of the homes. The predominant allergens were cat ( Fel d 1) and mouse ( Mus m 1) allergens, found in 20 and 34 homes, respectively.

  1. Household mold and dust allergens: Exposure, sensitization and childhood asthma morbidity

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

    Gent, Janneane F., E-mail: janneane.gent@yale.edu; Kezik, Julie M., E-mail: julie.colburn@yale.edu; Hill, Melissa E., E-mail: melissa.hill@yale.edu

    Background: Few studies address concurrent exposures to common household allergens, specific allergen sensitization and childhood asthma morbidity. Objective: To identify levels of allergen exposures that trigger asthma exacerbations in sensitized individuals. Methods: We sampled homes for common indoor allergens (fungi, dust mites (Der p 1, Der f 1), cat (Fel d 1), dog (Can f 1) and cockroach (Bla g 1)) for levels associated with respiratory responses among school-aged children with asthma (N=1233) in a month-long study. Blood samples for allergy testing and samples of airborne fungi and settled dust were collected at enrollment. Symptoms and medication use were recordedmore » on calendars. Combined effects of specific allergen sensitization and level of exposure on wheeze, persistent cough, rescue medication use and a 5-level asthma severity score were examined using ordered logistic regression. Results: Children sensitized and exposed to any Penicillium experienced increased risk of wheeze (odds ratio [OR] 2.12 95% confidence interval [CI] 1.12, 4.04), persistent cough (OR 2.01 95% CI 1.05, 3.85) and higher asthma severity score (OR 1.99 95% CI 1.06, 3.72) compared to those not sensitized or sensitized but unexposed. Children sensitized and exposed to pet allergen were at significantly increased risk of wheeze (by 39% and 53% for Fel d 1>0.12 {mu}g/g and Can f 1>1.2 {mu}g/g, respectively). Increased rescue medication use was significantly associated with sensitization and exposure to Der p 1>0.10 {mu}g/g (by 47%) and Fel d 1>0.12 {mu}g/g (by 32%). Conclusion: Asthmatic children sensitized and exposed to low levels of common household allergens Penicillium, Der p 1, Fel d 1 and Can f 1 are at significant risk for increased morbidity. - Highlights: Black-Right-Pointing-Pointer Few studies address concurrent allergen exposures, sensitization and asthma morbidity. Black-Right-Pointing-Pointer Children with asthma were tested for sensitivity to common indoor

  2. Allergens and β-Glucans in Dutch Homes and Schools: Characterizing Airborne Levels

    PubMed Central

    Krop, Esmeralda J. M.; Jacobs, José H.; Sander, Ingrid; Raulf-Heimsoth, Monika; Heederik, Dick J. J.

    2014-01-01

    Background Indoor air quality has an effect on respiratory health. Children are more vulnerable to a decreased indoor air quality as their lungs are still developing. We measured levels of allergens and β-(1,3)-glucans in 19 school buildings and determined whether measured levels could be reproduced. School levels were compared to those in 169 homes and the effect of building characteristics on both home and school exposure was explored. Methods Electrostatic Dust fall Collectors were placed in school buildings for 8 weeks and in homes for 2 weeks to collect settled airborne dust. Cat, dog, and mouse allergen levels, domestic mite antigen levels and β-(1,3)-glucans were measured in the extracts from the collectors. Results were corrected for sampling duration. Using questionnaire data, relations between measured levels and building and classroom characteristics were explored. Results In schools, exposure levels were highest in classrooms and were influenced by the socioeconomic status of the children, the season measurements were performed, moisture status of the building and pet ownership. Repeated measurements in different seasons and over the years showed significantly different levels. Home exposure was influenced by socioeconomic status, occupancy and pet ownership. Domestic mite antigen was found in higher levels in extracts from homes compared to schools while pet allergen levels were 13 times higher in schools compared to homes without pets. For mouse allergen overall levels of exposure were low but still two times higher in schools compared to homes. Levels of β-(1,3)-glucans were also approximately two times higher in schools than in homes. Conclusion Exposure levels of several allergens and β-(1,3)-glucans in schools differ over time and are higher than in homes. For children, exposure levels measured at school could contribute to their total exposure as especially animal allergen levels can be much higher in schools compared to homes. PMID:24551183

  3. The NPC2 protein: A novel dog allergen.

    PubMed

    Khurana, Taruna; Newman-Lindsay, Shoshana; Young, Philip R; Slater, Jay E

    2016-05-01

    Dogs are an important source of indoor allergens that cause rhinoconjunctivitis, urticaria, and asthma in sensitized individuals. Can f 1 is reported as a major dog allergen, but other allergens have also been identified. Identification of immunologically important allergens is important for both the diagnosis and treatment of dog allergy. To identify and characterize the canine NPC2 protein, a novel dog allergen. We screened commercial and laboratory-generated aqueous dog extracts by 2-dimensional polyacrylamide gel electrophoresis with IgE immunoblotting using human serum samples from 71 dog-allergic individuals. A target of interest was excised from the gel and sequenced. Canine NPC2 sequence was generated, and recombinant proteins expressed in yeast and bacteria were used to determine allergenicity. An IgE enzyme-linked immunosorbent assay was used for screening 71 dog-positive and 30 dog-negative serum samples. A 16-kDa protein (pK = 8.5) in dog allergen extracts was recognized by specific IgE. The protein was identified by sequencing as a CE1 protein or NPC2 protein. Human IgE bound to recombinant protein was expressed in both yeast and bacteria. Ten (14%) of 71 individuals had specific IgE to NPC2 protein from bacteria, and 12 (17%) had IgE to NPC2 protein from yeast. Binding of pooled dog-allergic serum IgE to the dust mite protein Der p 2 was partially inhibited by recombinant NPC2 protein. NPC2 protein, a member of the MD-2-related lipid recognition family, is identified as a dog allergen (Can f 7), with an apparent seroprevalence of 10% to 20%. Published by Elsevier Inc.

  4. Endotoxin as a determinant of asthma and wheeze among rural dwelling children and adolescents: A case–control study

    PubMed Central

    2012-01-01

    Background The association between endotoxin exposure and asthma is complex and has been associated with rural living. We examined the relationship between domestic endotoxin and asthma or wheeze among rural school-aged children (6–18 years) and assessed the interaction between endotoxin and other characteristics with these outcomes. Methods Between 2005 and 2007 we conducted a case–control study of children 6–18 years in the rural region of Humboldt, Canada. Cases (n = 102) reported doctor-diagnosed asthma or wheeze in the past year. Controls (n = 208) were randomly selected from children without asthma or wheeze. Data were collected to ascertain symptoms, asthma history and indoor environmental exposures (questionnaire), endotoxin (dust collection from the play area floor and child’s mattress), and tobacco smoke exposure (saliva collection). Statistical testing was completed using multiple logistic regression to account for potential confounders and to assess interaction between risk factors. A stratified analysis was also completed to examine the effect of personal history of allergy. Results Among children aged 6–12 years, mattress endotoxin concentration (EU/mg) and load (EU/m2) were inversely associated with being a case [odds ratio (OR) = 0.44, 95% confidence interval (CI) = 0.20-0.98; and OR = 0.38, 95% CI = 0.20-0.75, respectively]. These associations were not observed in older children or with play area endotoxin. Conclusions Our results suggest that endotoxin exposure might be protective for asthma or wheeze. The protective effect is found in younger school-aged, non-allergic children. These results may help explain the inconsistencies in previous studies and suggest that the protective effects of endotoxin in the prevention of atopy and asthma or wheeze are most effective earlier in life. PMID:22966977

  5. Altered immune responses in broiler chicken husbandry workers and their association with endotoxin exposure

    PubMed Central

    GAUTAM, Ravi; HEO, Yong; LIM, GyeongDong; SONG, EunSeob; ROQUE, Katharine; LEE, JaeHee; KIM, YeonGyeong; CHO, AhRang; SHIN, SoJung; KIM, ChangYul; BANG, GiHwan; BAHNG, JiYun; KIM, HyoungAh

    2017-01-01

    Exposure to bioaerosols in indoor animal farms associates with respiratory illnesses, but little is known about the immune modulation to chicken farmers. This study aimed to compare the general immunity of chicken farmers with those of control subjects with non-agricultural jobs. Blood taken from the farmers and controls was subjected to plasma IgE and IgG subclass measurements. Isolated peripheral blood mononuclear cells (PBMC) were stimulated and cytokine production was measured. Indoor total and respirable dust levels and their endotoxin (LPS) and aflatoxin (AF) levels in the farms were measured. In total, 29 chicken farmers on 19 farms and 14 age- and sex-matched office workers participated. Hematological differences were not observed. The farmers tended to have higher serum IgE and IgG subclass levels with significance for IgG1. The cytokines released by PBMC from farmers indicated skewing toward Type-2 helper T-cell responses: interferon (IFN)-γ:interleukin (IL)-4 and IFNγ:IL-13 ratios were significantly lower than for control PBMC. The farms had 707.1 EU/m3 LPS in total dust, and 15.8 EU/m3 LPS in respirable dust. Farmers exhibited immune skewing towards allergic immune responses that correlated with the LPS levels on their farms. Chicken farmers may be at risk of respiratory allergies due to occupational endotoxin exposure. PMID:28835578

  6. Classroom ventilation and indoor air quality-results from the FRESH intervention study.

    PubMed

    Rosbach, J; Krop, E; Vonk, M; van Ginkel, J; Meliefste, C; de Wind, S; Gehring, U; Brunekreef, B

    2016-08-01

    Inadequate ventilation of classrooms may lead to increased concentrations of pollutants generated indoors in schools. The FRESH study, on the effects of increased classroom ventilation on indoor air quality, was performed in 18 naturally ventilated classrooms of 17 primary schools in the Netherlands during the heating seasons of 2010-2012. In 12 classrooms, ventilation was increased to targeted CO2 concentrations of 800 or 1200 ppm, using a temporary CO2 controlled mechanical ventilation system. Six classrooms were included as controls. In each classroom, data on endotoxin, β(1,3)-glucans, and particles with diameters of <10 μm (PM10 ) and <2.5 μm (PM2.5 ) and nitrogen dioxide (NO2 ) were collected during three consecutive weeks. Associations between the intervention and these measured indoor air pollution levels were assessed using mixed models, with random classroom effects. The intervention lowered endotoxin and β(1,3)-glucan levels and PM10 concentrations significantly. PM10 for instance was reduced by 25 μg/m³ (95% confidence interval 13-38 μg/m³) from 54 μg/m³ at maximum ventilation rate. No significant differences were found between the two ventilation settings. Concentrations of PM2.5 and NO2 were not affected by the intervention. Our results provide evidence that increasing classroom ventilation is effective in decreasing the concentrations of some indoor-generated pollutants. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Quality of indoor residential air and health

    PubMed Central

    Dales, Robert; Liu, Ling; Wheeler, Amanda J.; Gilbert, Nicolas L.

    2008-01-01

    About 90% of our time is spent indoors where we are exposed to chemical and biological contaminants and possibly to carcinogens. These agents may influence the risk of developing nonspecific respiratory and neurologic symptoms, allergies, asthma and lung cancer. We review the sources, health effects and control strategies for several of these agents. There are conflicting data about indoor allergens. Early exposure may increase or may decrease the risk of future sensitization. Reports of indoor moulds or dampness or both are consistently associated with increased respiratory symptoms but causality has not been established. After cigarette smoking, exposure to environmental tobacco smoke and radon are the most common causes of lung cancer. Homeowners can improve the air quality in their homes, often with relatively simple measures, which should provide health benefits. PMID:18625986

  8. Isolation of Endotoxin Eliminating Lactic Acid Bacteria and a Property of Endotoxin Eliminating Protein.

    PubMed

    Kondo, Ayaka; Asami, Kyoko; Suda, Yoshihito; Shimoyamada, Makoto; Kanauchi, Makoto

    2016-06-01

    Recently, many scholars have reported lactic acid bacteria (LAB) functions, such as anticancer activity and anti-inflammatory activity for intestines. To decrease inflammatory substances such as endotoxins, LAB consumed safely with meals were isolated from food and food ingredients. First, LAB were isolated as 168 strains of bacillus LAB (49 strain) and coccus LAB (119 strains) from food ingredients and fermented foods such as rice, rice bran, malt, grains, miso soy paste, and some pickles. Their LAB (168 strains) were cultivated in medium containing endotoxin from Escherichia coli O18 LPS at 15 and 30 °C for 64 h to identify endotoxin-eliminating LAB. Consequently, the AK-23 strain was screened as an endotoxin-eliminating LAB strain. The strain decreased endotoxin in YP medium without sugar at 30 °C for 64 h until 9% of endotoxin. The strain was identified as Pediococcus pentosaceus according to morphological characteristics such as its cell shape, physiological characteristics related to its fermentation type, assimilation of sugars, pH tolerance, optimum growth temperature, and molecular biological characteristics as its homology to 16S rRNA. To investigate the location of the endotoxin-eliminating substance, 4 fractions were separated from AK-23 cells as extracellular, cell wall digestion, cytoplasm, and cell membrane fractions. The endotoxin-decreasing substance, located on a cell wall, was identified as a 217 kDa protein. © 2016 Institute of Food Technologists®

  9. Endotoxin hitchhiking on polymer nanoparticles

    NASA Astrophysics Data System (ADS)

    Donnell, Mason L.; Lyon, Andrew J.; Mormile, Melanie R.; Barua, Sutapa

    2016-07-01

    The control of microbial infections is critical for the preparation of biological media including water to prevent lethal septic shock. Sepsis is one of the leading causes of death in the United States. More than half a million patients suffer from sepsis every year. Both gram-positive and gram-negative bacteria are responsible for septic infection by the most common organisms i.e., Escherichia coli and Pseuodomonas aeruginosa. The bacterial cell membrane releases negatively charged endotoxins upon death and enzymatic destruction, which stimulate antigenic response in humans to gram-negative infections. Several methods including distillation, ethylene oxide treatment, filtration and irradiation have been employed to remove endotoxins from contaminated samples, however, the reduction efficiency remains low, and presents a challenge. Polymer nanoparticles can be used to overcome the current inability to effectively sequester endotoxins from water. This process is termed endotoxin hitchhiking. The binding of endotoxin on polymer nanoparticles via electrostatic and hydrophobic interactions offers efficient removal from water. However, the effect of polymer nanoparticles and its surface areas has not been investigated for removal of endotoxins. Poly(ε-caprolactone) (PCL) polymer was tested for its ability to effectively bind and remove endotoxins from water. By employing a simple one-step phase separation technique, we were able to synthesize PCL nanoparticles of 398.3 ± 95.13 nm size and a polydispersity index of 0.2. PCL nanoparticles showed ∼78.8% endotoxin removal efficiency, the equivalent of 3.9 × 105 endotoxin units (EU) per ml. This is 8.34-fold more effective than that reported for commercially available membranes. Transmission electron microscopic images confirmed binding of multiple endotoxins to the nanoparticle surface. The concept of using nanoparticles may be applicable not only to eliminate gram-negative bacteria, but also for any gram

  10. Rodent allergen in Los Angeles inner city homes of children with asthma.

    PubMed

    Berg, Jill; McConnell, Rob; Milam, Joel; Galvan, Judith; Kotlerman, Jenny; Thorne, Peter; Jones, Craig; Ferdman, Ronald; Eggleston, Peyton; Rand, Cynthia; Lewis, Mary Ann; Peters, John; Richardson, Jean

    2008-01-01

    Recent studies have examined the presence of mouse allergen in inner city children with asthma. Researchers have found high levels of rodent allergen in homes sampled in the northeast and midwest United States, but there has been considerable variation between cities, and there have been few studies conducted in western states. We evaluated the frequency of rodent sightings and detectable mouse allergen and the housing conditions associated with these outcomes in inner city homes in Los Angeles. Two hundred and two families of school children, ages 6-16 living in inner city neighborhoods, participated in the study. Families were predominantly Latino (94%), and Spanish speaking (92%). At study entry, parents completed a home assessment questionnaire, and staff conducted a home evaluation and collected kitchen dust, which was analyzed for the presence of mouse allergen. Fifty-one percent of homes had detectable allergen in kitchen dust. All 33 families who reported the presence of rodents had detectable allergen in the home and were also more likely to have increased levels of allergen compared to those who did not report rodents. Unwashed dishes or food crumbs, lack of a working vacuum, and a caretaker report of a smoker in the home were all significantly associated with a greater risk of rodent sightings or detectable allergen (P<0.05). Detached homes were significantly more likely to have detectable allergen. The prevalence of allergen is common enough that it may have public health implications for asthmatic children, and detectable allergen was not routinely identified based on rodent sightings. Many of the predictors of rodent allergen are amenable to low-cost interventions that can be integrated with other measures to reduce exposure to indoor allergens.

  11. Allergen exposure modifies the relation of sensitization to FENO levels in children at risk for allergy and asthma

    PubMed Central

    Sordillo, Joanne E; Webb, Tara; Kwan, Doris; Kamel, Jimmy; Hoffman, Elaine; Milton, Donald K; Gold, Diane R

    2011-01-01

    Background Studies on airway inflammation, measured as fraction exhaled nitric oxide (FENO), have focused on its relation to control of asthma, but the contribution of allergen exposure to elevation of FENO is unknown. Objective We evaluated (1) whether FENO was elevated in children with allergic sensitization or asthma; (2) whether specific allergen exposure increased FENO levels in sensitized, but not in unsensitized children; and (3) whether sedentary behavior increased FENO, independent of allergen exposures. Methods At age 12, in a birth cohort of children with parental history of allergy or asthma, we measured bed dust allergen (dust mite, cat, cockroach) by ELISA; specific allergic sensitization primarily by specific IgE ; and respiratory disease (current asthma, rhinitis, and wheeze) and hours of TV viewing/video game playing by questionnaire. Children performed spirometry maneuvers before and after bronchodilator responses, and had FENO measured using electrochemical detection methods (NIOX MINO). Results FENO was elevated in children with current asthma (32.2 ppb), wheeze (27.0 ppb), or rhinitis (23.2ppb) as compared to individuals without these respective symptoms/diagnoses (16.4 ppb to 16.6 ppb, p< 0.005 for all comparisons). Allergic sensitization to indoor allergens (cat, dog, dust mite) predicted higher levels of FENO, and explained one third of the variability of FENO. FENO levels were highest in children both sensitized and exposed to dust mite. Greater than 10 hours of weekday TV viewing was associated with a 0.64 log increase in FENO, after controlling indoor allergen exposure, BMI and allergic sensitization. Conclusion Allergen exposures and sedentary behavior (TV viewing/ video game playing), may increase airway inflammation, measured as FENO. PMID:21463890

  12. Allergen sensitization of asthmatic and nonasthmatic schoolchildren in Costa Rica.

    PubMed

    Soto-Quiros, M; Gutierrez, I; Calvo, N; Araya, C; Karlberg, J; Hanson, L A; Belin, L

    1998-12-01

    The prevalence of asthma among schoolchildren in Costa Rica is very high -- at the level of 20-30% -- and the reason is still unknown. A group of children from our previous epidemiologic study was randomly selected in order to establish the relation between asthma symptoms and allergy sensitization to common allergens. Serum samples from children with and without asthma were analyzed for the presence of IgE antibodies to 36 different allergens, for the presence of IgE antibodies to a pool of 10 common allergens, and for total serum IgE. The most prevalent IgE antibodies were those to mite, cockroach, dog, and house-dust allergens with MAST pipettes for the serologic measurements. Positive reactions to house dust, mite, cat, and the two molds (Alternaria and Cladosporium), and food allergens such as egg white, peanut, and shellfish were significantly more prevalent among the asthmatics than the nonasthmatics. Sensitization was equally prevalent at different ages, but the house-dust, mite, cat, dog, cockroach, Alternaria, and egg-white allergens had sensitized boys more often than girls (P < 0.01). The result of the analysis of IgE antibodies to a pool of 10 common allergens by Phadiatop supported the MAST pipette results, showing allergen sensitization in 57.7% of the asthmatic children and 42.3% in the nonasthmatic group. The concentration of IgE was significantly higher among the asthmatic children (372.2 kU/l) than among the nonasthmatic children (249.1 kU/l) (P < 0.00001). Parasitic infestations were not examined in this study, but in most of Costa Rica these have largely been eliminated and could not explain the high total IgE levels. Our data indicate that the very high prevalence of bronchial asthma in Costa Rican schoolchildren can be related to sensitization, especially to airborne indoor allergens such as those of mites, cockroaches, and dogs.

  13. Genetic variants in endotoxin signalling pathway, domestic endotoxin exposure and asthma exacerbations.

    PubMed

    Kljaic-Bukvic, Blazenka; Blekic, Mario; Aberle, Neda; Curtin, John A; Hankinson, Jenny; Semic-Jusufagic, Aida; Belgrave, Danielle; Simpson, Angela; Custovic, Adnan

    2014-10-01

    We investigated the interaction between genetic variants in endotoxin signalling pathway and domestic endotoxin exposure in relation to asthma presence, and amongst children with asthma, we explored the association of these genetic variants and endotoxin exposure with hospital admissions due to asthma exacerbations. In a case-control study, we analysed data from 824 children (417 asthmatics, 407 controls; age 5-18 yr). Amongst asthmatics, we extracted data on hospitalization for asthma exacerbation from medical records. Endotoxin exposure was measured in dust samples collected from homes. We included 26 single-nucleotide polymorphisms (SNPs) in the final analysis (5 CD14, 7LY96 and 14 TLR4). Two variants remained significantly associated with hospital admissions with asthma exacerbations after correction for multiple testing: for CD14 SNP rs5744455, carriers of T allele had decreased risk of repeated hospital admissions compared with homozygotes for C allele [OR (95% CI), 0.42 (0.25-0.88), p = 0.01, False Discovery Rate (FDR) p = 0.02]; for LY96 SNP rs17226566, C-allele carriers were at a lower risk of hospital admissions compared with T-allele homozygotes [0.59 (0.38-0.90), p = 0.01, FDR p = 0.04]. We observed two interactions between SNPs in CD14 and LY96 with environmental endotoxin exposure in relation to hospital admissions due to asthma exacerbation which remained significant after correction for multiple testing (CD14 SNPs rs2915863 and LY96 SNP rs17226566). Amongst children with asthma, genetic variants in CD14 and LY96 may increase the risk of hospital admissions with acute exacerbations. Polymorphisms in endotoxin pathway interact with domestic endotoxin exposure in further modification of the risk of hospitalization. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Socioeconomic predictors of high allergen levels in homes in the greater Boston area.

    PubMed

    Kitch, B T; Chew, G; Burge, H A; Muilenberg, M L; Weiss, S T; Platts-Mills, T A; O'Connor, G; Gold, D R

    2000-04-01

    In the United States, childhood asthma morbidity and prevalence rates are the highest in less affluent urban minority communities. More than 80% of childhood asthmatics are allergic to one or more inhalant allergens. We evaluated whether socioeconomic status was associated with a differential in the levels and types of indoor home allergens. Dust samples for an ELISA allergen assay were collected from the homes of 499 families as part of a metropolitan Boston, Massachusetts, longitudinal birth cohort study of home allergens and asthma in children with a parental history of asthma or allergy. The proportion of homes with maximum home allergen levels in the highest category was 42% for dust mite allergen (> or = 10 microg/g Der p 1 or Der f 1), 13% for cockroach allergen (> or = 2 U/g Bla g 1 or Bla g 2), 26% for cat allergen (> or = 8 microg/g Fel d 1), and 20% for dog allergen (> or = 10 microg/g Can f 1). Homes in the high-poverty area (> 20% of the population below the poverty level) were more likely to have high cockroach allergen levels than homes in the low-poverty area [51 vs. 3%; OR, 33; 95% confidence interval (CI), 12-90], but less likely to have high levels of dust mite allergen (16 vs. 53%; OR, 0.2; CI, 0.1-0.4). Lower family income, less maternal education, and race/ethnicity (black or Hispanic vs. white) were also associated with a lower risk of high dust mite levels and a greater risk of high cockroach allergen levels. Within a single U.S. metropolitan area we found marked between-community differences in the types of allergens present in the home, but not necessarily in the overall burden of allergen exposure.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

  17. Movement of Endotoxin Through Soil Columns

    PubMed Central

    Goyal, Sagar M.; Gerba, Charles P.; Lance, J. Clarence

    1980-01-01

    Land treatment of wastewater is an attractive alternative to conventional sewage treatment systems and is gaining widespread acceptance. Although land application systems prevent surface water pollution and augment the available water supplies, the potential dangers to human health should be evaluated. Since sewage may contain high amounts of bacterial endotoxin, the removal of endotoxin from sewage by percolation through soil was investigated. It was found that 90 to 99% of the endotoxin was removed after travel of sewage through 100 to 250 cm of loamy sand soil. When distilled water was allowed to infiltrate into the soil to simulate rainfall, the endotoxin was mobilized and moved in a concentrated band through the soil column. On testing samples from actual land treatment sites, as much as 480 ng of endotoxin per milliliter was found in some groundwater samples. The presence of endotoxin in potable water is known to be a potential problem under some circumstances, but the importance of endotoxin in water supplies has not been fully assessed. Therefore, the design, operation, and management of land application systems should take into account the fate of endotoxin in groundwater beneath the sites. PMID:7387154

  18. Hormone and Cytokine Responses to Repeated Endotoxin Exposures-No Evidence of Endotoxin Tolerance After 5 Weeks in Humans.

    PubMed

    Rittig, Nikolaj; Thomsen, Henrik H; Bach, Ermina; Jørgensen, Jens Otto L; Møller, Niels

    2015-07-01

    Endotoxin administrations are used in experimental models of inflammatory disease. Short-term endotoxin tolerance in response to repeated endotoxin exposure is well known, but the duration of endotoxin tolerance in humans remains unknown. The main purpose of this study was to test whether endotoxin tolerance is present in vivo when separating endotoxin exposures with more than 5 weeks, a time span often used between individual investigations in clinical experimental studies. Seventeen healthy young men were exposed twice to Escherichia coli endotoxin. The inflammatory response was calculated as area under the curve between the first and second endotoxin exposures for heart rate, mean arterial blood pressure, temperature, cortisol, tumor necrosis factor α, and interleukin (IL)-1β, IL-6, and IL-10. The median interval between exposures was 90 days (range, 37-244). The ratio between the inflammatory responses during the second and the first endotoxin exposures was 0.89 ± 0.09 (P = 0.28) for tumor necrosis factor α, 0.96 ± 0.07 (P = 0.53) for IL-1β, 0.97 ± 0.11 (P = 0.78) for IL-6, 1.30 ± 0.18 (P = 0.12) for IL-10, and 0.92 ± 0.04 (P = 0.10) for cortisol. Our data do not show evidence of in vivo tolerance to repeated endotoxin exposure when administrations are separated with at least 5 weeks. This observation is important in the planning and interpretation of future experimental endotoxin studies.

  19. Ventilation scheme, room location and meteorological factors influence indoor birch pollen concentrations

    NASA Astrophysics Data System (ADS)

    Jochner, Susanne; Matiu, Michael; Michaelis, Rico; Menzel, Annette

    2017-04-01

    Allergenic pollen, often in co-occurrence with air pollutants from traffic and industries aggravating its pollen allergenicity, constitutes a major health risk for the urban population during the pollen season. Airborne pollen concentrations are traditionally monitored with fixed pollen traps mounted >10 m above ground on flat roof tops. However, the personal exposure of allergic people mostly depends on their main residences and the local emission patterns. Consequently, the assessment of indoor pollen is essential for human health since people stay most of the day inside buildings. In our study, hourly indoor birch pollen concentrations were measured on eight days in April 2015 with portable pollen traps in five rooms of a university building at Freising, Germany. A traditional pollen trap on the roof of the building provided the background birch pollen concentration which was compared to the respective outdoor values right in front of the rooms. The office and lab rooms were characterised by different aspects and window ventilation schemes. Meteorological data were equally measured at a nearby climate station and directly in front of the windows. The observed flowering phenology of 56 birch trees in the nearer surrounding partly explained daily peaks in airborne pollen concentrations. As expected, outdoor pollen concentrations were larger than indoor concentrations: Mean indoor/outdoor (I/O) ratio was highest (0.75) in a south oriented room with fully opened window and additional mechanical ventilation, followed by two rooms with fully opened windows orientated to the west and north (0.35, 0.12) and lowest in east oriented neighbouring rooms with tilted window (0.19) and with windows only opened for short ventilation (0.07). The latter two rooms even had a birch tree directly flowering in front of the façade. Hourly I/O ratios depended on meteorology and increased with outside temperature and wind speed oriented perpendicular to the window opening. As also

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

    PubMed

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

    1996-09-01

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

  1. Endotoxin Studies And Biosolids Stabilization Research

    EPA Science Inventory

    This presentation has three parts; a review of bench-scale endotoxin research, a review of observations from a field scale endotoxin release study, and discussion of biosolids stabilization and characterization by PLFA/FAME microbial community analysis. Endotoxins are part of th...

  2. EFFECTS OF BACTERIAL ENDOTOXINS ON METABOLISM

    PubMed Central

    Berry, L. Joe; Smythe, Dorothy S.

    1961-01-01

    In vitro secretion of glycocorticoids by adrenal glands pooled from several control mice was compared with that of glands removed from animals following injections of either ACTH or endotoxin. Both substances prevent glycocorticoid synthesis stimulated in vitro with ACTH. Cholesterol content of adrenal glands under these conditions was nearly depleted, indicating maximal response to ACTH or endotoxin prior to their removal for the in vitro tests. In an effort to account physiologically for the manner in which endotoxin suppresses or prevents the rise in urinary nitrogen excreted in response to ACTH, blood non-protein nitrogen levels (NPN) were determined. The following experimental conditions resulted in increased urinary nitrogen excretion but did not alter blood NPN: cortisone given alone or at the same time as endotoxin; ACTH alone; dichloroisoproterenol (DCI) given concurrently with endotoxin; and lactalbumin digest injected intraperitoneally. Increases (2- to 3-fold) in blood NPN were observed when endotoxin was given alone, concurrently with ACTH, or 3 hours prior to cortisone, DCI, or lactalbumin digest. Urinary nitrogen excretion showed no change under these conditions. The elevation in blood NPN in endotoxin-poisoned mice was found to be due almost entirely to urea nitrogen and not to amino acid nitrogen or to other nitrogenous wastes. Blood clearance of mulin, phenol red excretion, and urea elimination were each determined in control and in endotoxin-poisoned mice. The latter mice showed impaired renal function. Treatment with diuretics (diuril and aminophylline) failed to alter oliguria or elevated blood NPN. Hydergine treatment was also without effect. Total carcass NPN and urinary nitrogen excretion data were combined to give a picture of total protein catabolized by mice under different experimental conditions. Cortisone injected at the same time as endotoxin or 3 hours later resulted in the same increase in total NPN. However, in the former case all

  3. Indoor Air Quality in Schools (IAQ): The Importance of Monitoring Carbon Dioxide Levels.

    ERIC Educational Resources Information Center

    Sundersingh, David; Bearg, David W.

    This article highlights indoor air quality and exposure to pollutants at school. Typical air pollutants within schools include environmental tobacco smoke, formaldehyde, volatile organic compounds, nitrogen oxides, carbon monoxide, carbon dioxide, allergens, pathogens, radon, pesticides, lead, and dust. Inadequate ventilation, inefficient…

  4. Indoor air quality in Latino homes in Boulder, Colorado

    NASA Astrophysics Data System (ADS)

    Escobedo, Luis E.; Champion, Wyatt M.; Li, Ning; Montoya, Lupita D.

    2014-08-01

    Indoor concentrations of airborne pollutants can be several times higher than those found outdoors, often due to poor ventilation, overcrowding, and the contribution of indoor sources within a home. Americans spend most of their time indoors where exposure to poor indoor air quality (IAQ) can result in diminished respiratory and cardiovascular health. This study measured the indoor air quality in 30 homes of a low-income Latino community in Boulder, Colorado during the summer of 2012. Participants were administered a survey, which included questions on their health conditions and indoor air pollution sources like cigarette smoke, heating fuel, and building materials. Twenty-four hour samples of fine particulate matter (PM2.5) from the indoor air were collected in each home; ambient PM2.5 samples were collected each day as well. Concurrent air samples were collected onto 47 mm Teflo and Tissuquartz filter at each location. Teflo filters were analyzed gravimetrically to measure PM2.5 and their extracts were used to determine levels of proteins and endotoxins in the fine fraction. The Tissuquartz filters were analyzed for elemental and organic carbon content (EC/OC). Results indicated that the indoor air contained higher concentrations of PM2.5 than the ambient air, and that the levels of OC were much higher than EC in both indoor and outdoor samples. This community showed no smoking in their homes and kept furry pets indoors at very low rates; therefore, cooking is likely the primary source of indoor PM. For responders with significant exposure to PM, it appeared to be primarily from occupational environments or childhood exposure abroad. Our findings indicate that for immigrant communities such as this, it is important to consider not only their housing conditions but also the relevant prior exposures when conducting health assessments.

  5. Characterization of airborne molds, endotoxins, and glucans in homes in New Orleans after Hurricanes Katrina and Rita.

    PubMed

    Rao, Carol Y; Riggs, Margaret A; Chew, Ginger L; Muilenberg, Michael L; Thorne, Peter S; Van Sickle, David; Dunn, Kevin H; Brown, Clive

    2007-03-01

    In August and September 2005, Hurricanes Katrina and Rita caused breeches in the New Orleans, LA, levee system, resulting in catastrophic flooding. The city remained flooded for several weeks, leading to extraordinary mold growth in homes. To characterize the potential risks of mold exposures, we measured airborne molds and markers of molds and bacteria in New Orleans area homes. In October 2005, we collected air samples from 5 mildly water-damaged houses, 15 moderately to heavily water-damaged houses, and 11 outdoor locations. The air filters were analyzed for culturable fungi, spores, (1-->3,1-->6)-beta-D-glucans, and endotoxins. Culturable fungi were significantly higher in the moderately/heavily water-damaged houses (geometric mean=67,000 CFU/m3) than in the mildly water-damaged houses (geometric mean=3,700 CFU/m3) (P=0.02). The predominant molds found were Aspergillus niger, Penicillium spp., Trichoderma, and Paecilomyces. The indoor and outdoor geometric means for endotoxins were 22.3 endotoxin units (EU)/m3 and 10.5 EU/m3, respectively, and for (1-->3,1-->6)-beta-D-glucans were 1.7 microg/m3 and 0.9 microg/m3, respectively. In the moderately/heavily water-damaged houses, the geometric means were 31.3 EU/m3 for endotoxins and 1.8 microg/m3 for (1-->3,1-->6)-beta-D-glucans. Molds, endotoxins, and fungal glucans were detected in the environment after Hurricanes Katrina and Rita in New Orleans at concentrations that have been associated with health effects. The species and concentrations were different from those previously reported for non-water-damaged buildings in the southeastern United States.

  6. Allergenically active components of cat allergen extracts.

    PubMed

    Anderson, M C; Baer, H

    1981-09-01

    The allergens involved in cat allergy have been studied in pelt extracts, saliva, serum, and urine. Using crossed immunoelectrophoresis (CIE) to examine the antigenic content, and crossed radioimmunoelectrophoresis (CRIE) and RAST to examine the allergenic content, it was found that allergen 1 of Dr. Ohman is the most important allergenic component, whereas albumin and several unidentified proteins play a minor role. Allergen 1 was not detectable in serum and urine. The allergenic and nonallergenic proteins of pelt extract and saliva were identical by CIE, suggesting that pelt extract proteins are mainly of salivary origin.

  7. Mold and Endotoxin Levels in the Aftermath of Hurricane Katrina: A Pilot Project of Homes in New Orleans Undergoing Renovation

    PubMed Central

    Chew, Ginger L.; Wilson, Jonathan; Rabito, Felicia A.; Grimsley, Faye; Iqbal, Shahed; Reponen, Tiina; Muilenberg, Michael L.; Thorne, Peter S.; Dearborn, Dorr G.; Morley, Rebecca L.

    2006-01-01

    Background After Hurricane Katrina, many New Orleans homes remained flooded for weeks, promoting heavy microbial growth. Objectives A small demonstration project was conducted November 2005–January 2006 aiming to recommend safe remediation techniques and safe levels of worker protection, and to characterize airborne mold and endotoxin throughout cleanup. Methods Three houses with floodwater lines between 0.3 and 2 m underwent intervention, including disposal of damaged furnishings and drywall, cleaning surfaces, drying remaining structure, and treatment with a biostatic agent. We measured indoor and outdoor bioaerosols before, during, and after intervention. Samples were analyzed for fungi [culture, spore analysis, polymerase chain reaction (PCR)] and endotoxin. In one house, real-time particle counts were also assessed, and respirator-efficiency testing was performed to establish workplace protection factors (WPF). Results At baseline, culturable mold ranged from 22,000 to 515,000 colony-forming units/m3, spore counts ranged from 82,000 to 630,000 spores/m3, and endotoxin ranged from 17 to 139 endotoxin units/m3. Culture, spore analysis, and PCR indicated that Penicillium, Aspergillus, and Paecilomyces predominated. After intervention, levels of mold and endotoxin were generally lower (sometimes, orders of magnitude). The average WPF against fungal spores for elastomeric respirators was higher than for the N-95 respirators. Conclusions During baseline and intervention, mold and endotoxin levels were similar to those found in agricultural environments. We strongly recommend that those entering, cleaning, and repairing flood-damaged homes wear respirators at least as protective as elastomeric respirators. Recommendations based on this demonstration will benefit those involved in the current cleanup activities and will inform efforts to respond to future disasters. PMID:17185280

  8. Mold and endotoxin levels in the aftermath of Hurricane Katrina: a pilot project of homes in New Orleans undergoing renovation.

    PubMed

    Chew, Ginger L; Wilson, Jonathan; Rabito, Felicia A; Grimsley, Faye; Iqbal, Shahed; Reponen, Tiina; Muilenberg, Michael L; Thorne, Peter S; Dearborn, Dorr G; Morley, Rebecca L

    2006-12-01

    After Hurricane Katrina, many New Orleans homes remained flooded for weeks, promoting heavy microbial growth. A small demonstration project was conducted November 2005-January 2006 aiming to recommend safe remediation techniques and safe levels of worker protection, and to characterize airborne mold and endotoxin throughout cleanup. Three houses with floodwater lines between 0.3 and 2 m underwent intervention, including disposal of damaged furnishings and drywall, cleaning surfaces, drying remaining structure, and treatment with a biostatic agent. We measured indoor and outdoor bioaerosols before, during, and after intervention. Samples were analyzed for fungi [culture, spore analysis, polymerase chain reaction (PCR)] and endotoxin. In one house, realtime particle counts were also assessed, and respirator-efficiency testing was performed to establish workplace protection factors (WPF). At baseline, culturable mold ranged from 22,000 to 515,000 colony-forming units/m3, spore counts ranged from 82,000 to 630,000 spores/m3, and endotoxin ranged from 17 to 139 endotoxin units/m3. Culture, spore analysis, and PCR indicated that Penicillium, Aspergillus, and Paecilomyces predominated. After intervention, levels of mold and endotoxin were generally lower (sometimes, orders of magnitude). The average WPF against fungal spores for elastomeric respirators was higher than for the N95 respirators. During baseline and intervention, mold and endotoxin levels were similar to those found in agricultural environments. We strongly recommend that those entering, cleaning, and repairing flood-damaged homes wear respirators at least as protective as elastomeric respirators. Recommendations based on this demonstration will benefit those involved in the current cleanup activities and will inform efforts to respond to future disasters.

  9. Socioeconomic factors and home allergen exposure in children with asthma.

    PubMed

    Ungar, Wendy J; Cope, Shannon F; Kozyrskyj, Anita; Paterson, J Michael

    2010-01-01

    The objective of this study was to determine the association between sociodemographic factors and the elimination of allergen sources from homes of asthmatic children. In a cross-sectional analysis of data from 845 asthmatic children, multiple linear regression investigated the association between socioeconomic factors and failure to reduce allergen sources (i.e., stuffed toys, pets, carpeting, curtains, and cushions); failure to use linen covers; and not laundering linens weekly in hot water. Logistic regression assessed the relationship between socioeconomic status and exposure to environmental tobacco smoke. Mother's employment status was significantly associated with the quality of the home environment (P = .0002). Homemakers demonstrated fewer poor practices (3.1) compared with full-time or part-time employed mothers (3.6). Children whose mothers reported no post-secondary education were more likely to have environmental tobacco smoke exposure compared with those who had a post-secondary CE education or higher (OR 2.4, 95% CI 1.7, 3.5). Children whose mothers worked at home and were better educated were at reduced risk for exposure to sources of indoor allergens.

  10. Endotoxins in cotton: washing effects and size distribution

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

    Olenchock, S.A.; Mull, J.C.; Jones, W.G.

    1983-01-01

    Endotoxin contamination was measured in washed and unwashed cottons from three distinct growing areas, California, Mississippi, and Texas. The data show differences in endotoxin contamination based upon the geographic source of the cotton. It is also shown that washing bulk cotton before the carding process results in lower endotoxin in the cotton dust. Washing conditions can affect the endotoxin levels, and all size fractions of the airborne dust contain quantifiable endotoxin contamination. Endotoxin analyses provide a simple and reliable method for monitoring the cleanliness of cotton or airborne cotton dusts.

  11. Binding of /sup 125/I-labeled endotoxin to bovine, canine, and equine platelets and endotoxin-induced agglutination of canine platelets

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

    Meyers, K.M.; Boehme, M.; Inbar, O.

    Endotoxin from Escherichia coli O127:B8, Salmonella abortus-equi and S minnesota induced clumping of some canine platelets (PLT) at a final endotoxin concentration of 1 microgram/ml. Endotoxin-induced clumping of canine PLT was independent of PLT energy-requiring processes, because clumping was observed with canine PLT incubated with 2-deoxy-D-glucose and antimycin A. The PLT responded to adenosine diphosphate before, but not after, incubation with the metabolic inhibitors. Endotoxin induced a slight and inconsistant clumping of bovine and equine PLT at high (mg/ml) endotoxin concentration. High-affinity binding sites could not be demonstrated on canine, bovine, and equine PLT, using /sup 125/I-labeled E coli O127:B8more » endotoxin. Nonspecific binding was observed and appeared to be due primarily to an extraneous coat on the PLT surface that was removed by gel filtration. The endotoxin that was bound to PLT did not appear to modify PLT function. An attempt to identify plasma proteins that bound physiologically relevant amounts of endotoxin was not successful. The significance of the endotoxin-induced clumping or lack of it on the pathophysiology of endotoxemia is discussed.« less

  12. Measurement of endotoxin.

    PubMed

    Phillips, J; Harrison, P; Hale, G

    2000-01-01

    Bacterial endotoxin is probably the most common significant contaminant that might be found in antibody preparations. It is found ubiquitously in normal environments but its pyrogenic effects in vivo can be lethal. It is absolutely vital to control the level of endotoxin in therapeutic products, but its significance for experimental work must not be underestimated since it can have numerous confounding effects both in vivo and in vitro. Methods for removing endotoxin from products have been described (1-4), but in our experience, it is much better to avoid it from the beginning by scrupulous control of raw materials and use of good aseptic technique. To grow, bacteria need water; therefore, the most likely sources of endotoxin are water and any process equipment that has been wet. Water must be obtained from a controlled source that is low in endotoxin. If you do not have a suitable dedicated water purification system, then it is best to purchase purified water. Water for irrigation (from a pharmaceutical supplier) is possibly the most economic. Equipment in contact with cells or products should preferably be sterile disposable plastic. Standard tissue culture ware is usually very reliable. Plastic bags for media and process intermediates are now widely available in all sizes (e.g., Stedim, Aubagne, France) and should be used in preference to glass bottles. Silicone tubing (food or medical grade) is suitable for all fluid transfers and should not be reused. If reusable equipment is essential, it can be soaked in 0.5 M NaOH and/or baked in an oven at high temperature (steam sterilization is not sufficient) (1).

  13. Is there a threshold concentration of cat allergen exposure on respiratory symptoms in adults?

    PubMed

    Chen, Chih-Mei; Thiering, Elisabeth; Zock, Jan-Paul; Villani, Simona; Olivieri, Mario; Modig, Lars; Jarvis, Deborah; Norbäck, Dan; Verlato, Giuseppe; Heinrich, Joachim

    2015-01-01

    Cat allergen concentrations higher than 8 μg/g in settled house dust, have been suggested to provoke exacerbation of allergic respiratory symptoms. However, whether the 8 μg/g of indoor cat allergen concentration is indeed the minimal exposure required for triggering the asthma related respiratory symptoms or the development of sensitization has not yet been confirmed. We studied the associations between domestic cat allergen concentrations and allergic symptoms in the European Community Respiratory Health Survey II, with the aim of confirming this suggested threshold. Cat allergen concentrations were measured in the mattress dust of 3003 participants from 22 study centres. Levels of specific immunoglobulin E to cat allergens were measured in serum samples using an immunoassay. Information on allergic symptoms, medication use, home environment and smoking was obtained from a face-to-face interview. Domestic cat allergen concentrations were not associated with allergic/ asthmatic symptoms in the entire study population, nor in the subset sensitized to cat allergen. We also found no association among individuals exposed to concentrations higher than 8 μg/g. However, exposure to medium cat allergen concentrations (0.24-0.63 μg/g) was positively associated with reported asthmatic respiratory symptoms in subjects who have experienced allergic symptoms when near animals. The proposed 8 μg/g threshold of cat allergen concentrations for the exacerbation of allergic/ respiratory symptoms was not confirmed in a general European adult population. Potential biases attributable to avoidance behaviours and an imprecise exposure assessment cannot be excluded.

  14. Is There a Threshold Concentration of Cat Allergen Exposure on Respiratory Symptoms in Adults?

    PubMed Central

    Zock, Jan-Paul; Villani, Simona; Olivieri, Mario; Modig, Lars; Jarvis, Deborah; Norbäck, Dan; Verlato, Giuseppe; Heinrich, Joachim

    2015-01-01

    Background and Objective Cat allergen concentrations higher than 8 μg/g in settled house dust, have been suggested to provoke exacerbation of allergic respiratory symptoms. However, whether the 8μg/g of indoor cat allergen concentration is indeed the minimal exposure required for triggering the asthma related respiratory symptoms or the development of sensitization has not yet been confirmed. We studied the associations between domestic cat allergen concentrations and allergic symptoms in the European Community Respiratory Health Survey II, with the aim of confirming this suggested threshold. Methods Cat allergen concentrations were measured in the mattress dust of 3003 participants from 22 study centres. Levels of specific immunoglobulin E to cat allergens were measured in serum samples using an immunoassay. Information on allergic symptoms, medication use, home environment and smoking was obtained from a face-to-face interview. Results Domestic cat allergen concentrations were not associated with allergic/ asthmatic symptoms in the entire study population, nor in the subset sensitized to cat allergen. We also found no association among individuals exposed to concentrations higher than 8 μg/g. However, exposure to medium cat allergen concentrations (0.24-0.63 μg/g) was positively associated with reported asthmatic respiratory symptoms in subjects who have experienced allergic symptoms when near animals. Conclusions The proposed 8 μg/g threshold of cat allergen concentrations for the exacerbation of allergic/ respiratory symptoms was not confirmed in a general European adult population. Potential biases attributable to avoidance behaviours and an imprecise exposure assessment cannot be excluded. PMID:26035304

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

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

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

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

  16. Polymorphisms of endotoxin pathway and endotoxin exposure: in vitro IgE synthesis and replication in a birth cohort.

    PubMed

    Sahiner, U M; Semic-Jusufagic, A; Curtin, J A; Birben, E; Belgrave, D; Sackesen, C; Simpson, A; Yavuz, T S; Akdis, C A; Custovic, A; Kalayci, O

    2014-12-01

    Genetic variants in endotoxin signaling pathway are important in modulating the effect of environmental endotoxin on asthma and atopic phenotypes. Our objective was to determine the single nucleotide polymorphisms (SNPs) in the endotoxin signaling pathway that may influence in vitro IgE synthesis and to investigate the relationship between these variants and endotoxin exposure in relation to the development of asthma and atopy in a birth cohort. Peripheral blood mononuclear cells from 45 children with asthma were stimulated with 2 and 200 ng/ml lipopolysaccharide in vitro and IgE was measured in the culture supernatants. Children were genotyped for 121 SNPs from 30 genes in the endotoxin signaling pathway. Variants with a dose-response IgE production in relation to lipopolysaccharide (LPS) were selected for replication in a population-based birth cohort, in which we investigated the interaction between these SNPs and endotoxin exposure in relation to airway hyper-responsiveness, wheeze, and atopic sensitization. Twenty-one SNPs in nine genes (CD14, TLR4, IRF3, TRAF-6, TIRAP, TRIF, IKK-1, ST-2, SOCS1) were found to modulate the effect of endotoxin on in vitro IgE synthesis, with six displaying high linkage disequilibrium. Of the remaining 15 SNPs, for seven we found significant relationships between genotype and endotoxin exposure in the genetic association study in relation to symptomatic airway hyper-responsiveness (CD14-rs2915863 and rs2569191, TRIF-rs4807000), current wheeze (ST-2-rs17639215, IKK-1-rs2230804, and TRIF-rs4807000), and atopy (CD14-rs2915863 and rs2569192, TRAF-6-rs5030411, and IKK-1-rs2230804). Variants in the endotoxin signaling pathway are important determinants of asthma and atopy. The genotype effect is a function of the environmental endotoxin exposure. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. An update on molecular cat allergens: Fel d 1 and what else? Chapter 1: Fel d 1, the major cat allergen.

    PubMed

    Bonnet, B; Messaoudi, K; Jacomet, F; Michaud, E; Fauquert, J L; Caillaud, D; Evrard, B

    2018-01-01

    Cats are the major source of indoor inhalant allergens after house dust mites. The global incidence of cat allergies is rising sharply, posing a major public health problem. Ten cat allergens have been identified. The major allergen responsible for symptoms is Fel d 1, a secretoglobin and not a lipocalin, making the cat a special case among mammals. Given its clinical predominance, it is essential to have a good knowledge of this allergenic fraction, including its basic structure, to understand the new exciting diagnostic and therapeutic applications currently in development. The recent arrival of the component-resolved diagnosis, which uses molecular allergens, represents a unique opportunity to improve our understanding of the disease. Recombinant Fel d 1 is now available for in vitro diagnosis by the anti-Fel d 1 specific IgE assay. The first part of the review will seek to describe the recent advances related to Fel d 1 in terms of positive diagnosis and assessment of disease severity. In daily practice, anti-Fel d 1 IgE tend to replace those directed against the overall extract but is this attitude justified? We will look at the most recent arguments to try to answer this question. In parallel, a second revolution is taking place thanks to molecular engineering, which has allowed the development of various forms of recombinant Fel d 1 and which seeks to modify the immunomodulatory properties of the molecule and thus the clinical history of the disease via various modalities of anti-Fel d 1-specific immunotherapy. We will endeavor to give a clear and practical overview of all these trends.

  18. Allergenicity and cross-reactivity of booklice (Liposcelis bostrichophila): a common household insect pest in Japan.

    PubMed

    Fukutomi, Yuma; Kawakami, Yuji; Taniguchi, Masami; Saito, Akemi; Fukuda, Azumi; Yasueda, Hiroshi; Nakazawa, Takuya; Hasegawa, Maki; Nakamura, Hiroyuki; Akiyama, Kazuo

    2012-01-01

    Booklice (Liposcelis bostrichophila) are a common household insect pest distributed worldwide. Particularly in Japan, they infest 'tatami' mats and are the most frequently detected insect among all detectable insects, present at a frequency of about 90% in dust samples. Although it has been hypothesized that they are an important indoor allergen, studies on their allergenicity have been limited. To clarify the allergenicity of booklice and the cross-reactivity of this insect allergen with allergens of other insects, patients sensitized to booklice were identified from 185 Japanese adults with allergic asthma using skin tests and IgE-ELISA. IgE-inhibition analysis, immunoblotting and immunoblotting-inhibition analysis were performed using sera from these patients. Allergenic proteins contributing to specific sensitization to booklice were identified by two-dimensional electrophoresis and two-dimensional immunoblotting. The booklouse-specific IgE antibody was detected in sera from 41 patients (22% of studied patients). IgE inhibition analysis revealed that IgE reactivity to the booklouse allergen in the sera from one third of booklouse-sensitized patients was not inhibited by preincubation with extracts from any other environmental insects in this study. Immunoblotting identified a 26-kD protein from booklouse extract as the allergenic protein contributing to specific sensitization to booklice. The amino acid sequence of peptide fragments of this protein showed no homology to those of previously described allergenic proteins, indicating that this protein is a new allergen. Sensitization to booklice was relatively common and specific sensitization to this insect not related to insect panallergy was indicated in this population. Copyright © 2011 S. Karger AG, Basel.

  19. SUBCHRONIC ENDOTOXIN INHALATION CAUSES PERSISTENT AIRWAY DISEASE

    EPA Science Inventory

    ABSTRACT

    The endotoxin component of organic dusts causes acute reversible airflow obstruction and airway inflammation. To test the hypothesis that endotoxin alone causes airway remodeling, we have compared the response of two inbred mouse strains to subchronic endotoxin ...

  20. Characterization of Airborne Molds, Endotoxins, and Glucans in Homes in New Orleans after Hurricanes Katrina and Rita▿

    PubMed Central

    Rao, Carol Y.; Riggs, Margaret A.; Chew, Ginger L.; Muilenberg, Michael L.; Thorne, Peter S.; Van Sickle, David; Dunn, Kevin H.; Brown, Clive

    2007-01-01

    In August and September 2005, Hurricanes Katrina and Rita caused breeches in the New Orleans, LA, levee system, resulting in catastrophic flooding. The city remained flooded for several weeks, leading to extraordinary mold growth in homes. To characterize the potential risks of mold exposures, we measured airborne molds and markers of molds and bacteria in New Orleans area homes. In October 2005, we collected air samples from 5 mildly water-damaged houses, 15 moderately to heavily water-damaged houses, and 11 outdoor locations. The air filters were analyzed for culturable fungi, spores, (1→3,1→6)-β-d-glucans, and endotoxins. Culturable fungi were significantly higher in the moderately/heavily water-damaged houses (geometric mean = 67,000 CFU/m3) than in the mildly water-damaged houses (geometric mean = 3,700 CFU/m3) (P = 0.02). The predominant molds found were Aspergillus niger, Penicillium spp., Trichoderma, and Paecilomyces. The indoor and outdoor geometric means for endotoxins were 22.3 endotoxin units (EU)/m3 and 10.5 EU/m3, respectively, and for (1→3,1→6)-β-d-glucans were 1.7 μg/m3 and 0.9 μg/m3, respectively. In the moderately/heavily water-damaged houses, the geometric means were 31.3 EU/m3 for endotoxins and 1.8 μg/m3 for (1→3,1→6)-β-d-glucans. Molds, endotoxins, and fungal glucans were detected in the environment after Hurricanes Katrina and Rita in New Orleans at concentrations that have been associated with health effects. The species and concentrations were different from those previously reported for non-water-damaged buildings in the southeastern United States. PMID:17209066

  1. Endotoxin content in endodontically involved teeth. 1975.

    PubMed

    Schein, Benjamin; Schilder, Herbert

    2006-04-01

    Fluid was aspirated from the root canals of 40 endodontically involved teeth. This fluid was assayed for endotoxin with the limulus lysate test. Pulpless teeth contained greater concentrations of endotoxin than those with vital pulps. Symptomatic teeth also contained more endotoxin than asymptomatic teeth.

  2. Airborne endotoxin in fine particulate matter in Beijing

    NASA Astrophysics Data System (ADS)

    Guan, Tianjia; Yao, Maosheng; Wang, Junxia; Fang, Yanhua; Hu, Songhe; Wang, Yan; Dutta, Anindita; Yang, Junnan; Wu, Yusheng; Hu, Min; Zhu, Tong

    2014-11-01

    Endotoxin is an important biological component of particulate matter (PM) which, upon inhalation, can induce adverse health effects, and also possibly complicate the diseases in combination with other pollutants. From 1 March 2012 to 27 February 2013 we collected air samples using quartz filters daily for the quantification of airborne endotoxin and also fine PM (PM2.5) in Beijing, China. The geometric means for endotoxin concentration and the fraction of endotoxin in PM were 0.65 EU/m3 (range: 0.10-75.02) and 10.25 EU/mg PM2.5 (range: 0.38-1627.29), respectively. The endotoxin concentrations were shown to vary greatly with seasons, typically with high values in the spring and winter seasons. Temperature and relative humidity, as well as concentrations of sulfur dioxide and nitrogen oxides were found to be significantly correlated with airborne endotoxin concentrations (p < 0.05). Additionally, positive correlations were also detected between endotoxin concentrations and natural sources of Na+, K+, Mg2+, and F-, while negative correlations were observed between endotoxin concentrations and anthropogenic sources of P, Co, Zn, As, and Tl. Oxidative potential analysis revealed that endotoxin concentrations were positively correlated with reactive oxygen species (ROS), but not dithiothreitol (DTT) of PM. This study provided the first continuous time series of airborne endotoxin concentrations in Beijing, and identifies its potential associations with atmospheric factors. The information developed here can assist in the assessment of health effects of air pollution in Beijing.

  3. Biochemical and molecular biological aspects of silverfish allergens.

    PubMed

    Barletta, Bianca; Di Felice, Gabriella; Pini, Carlo

    2007-01-01

    Insects and insect-derived materials have been implicated as a risk factor for sensitization and subsequent elicitation of allergic rhinitis and allergic bronchial asthma. During the last decades, insects other than those known as allergenic, were investigated for their potential role in inducing and triggering an IgE immune response. Among these, the silverfish, an insect belonging to the Thysanura order, appeared to be of particular interest. Silverfish (Lepisma saccharina) is the most primitive living insect, and represents a descendent of the ancestral wingless insects. They are 3-12 mm long, have three tail feelers and are covered with shiny scales. They shun light and need a humid environment and their diet consists of carbohydrate materials such as paper and book-binding glue, crumbs of bread and flour. Because of these features, silverfish finds an optimal habitat both in dwellings and workplaces and in spite of its antiquity, silverfish has succeeded in exploiting the new opportunity created by man. Although its importance significantly increased when it has been demonstrated that house dust contains significant silverfish levels even in houses where the inhabitants were unaware of its presence, no silverfish extract for diagnosis of allergic diseases is commercially available yet. Identification of optimal extraction conditions and characterization of allergenic extracts are the first steps to obtain an effective allergen preparation suitable for diagnosis and therapy, and will be useful as a reference preparation for assessing silverfish exposure in different indoor environments. It has been cloned and characterized a silverfish tropomyosin, named Lep s 1, which represents the first allergen identified in silverfish extract and can be regarded as a molecule cross-reactive among inhalant and edible invertebrates allergenic sources. rLep s 1 displayed biological activity, suggesting that it could be regarded as a useful tool to study the role of silverfish

  4. Detecting endotoxin with a flow cytometry-based magnetic aptasensor.

    PubMed

    Zuo, Ming-Yan; Chen, Li-Juan; Jiang, Hao; Tan, Lin; Luo, Zhao-Feng; Wang, Yan-Mei

    2014-12-01

    Endotoxin, which is also known as lipopolysaccharide (LPS), is a marker for intruding gram-negative pathogens. It is essential to detect endotoxin quickly and sensitively in a complex milieu. A new flow cytometry (FCM)-based magnetic aptasensor assay that employs two endotoxin-binding aptamers and magnetic beads has been developed to detect endotoxin. The endotoxin-conjugated sandwich complex on magnetic beads was observed by scanning confocal laser microscopy. The resulting magnetic aptasensor rapidly detected (<1 min) endotoxin within a broad dynamic detection range of 10(-8) to 10(0)mg/ml in the presence of bovine serum albumin (BSA), RNA, sucrose, and glucose, which are most likely to coexist with endotoxin in the majority of biological liquids. Only 2 μl of magnetic aptasensor was required to quantify the endotoxin solution. Furthermore, the magnetic aptasensor could be regenerated seven times and still presented an outstanding response to the endotoxin solution. Therefore, the magnetic aptasensor exhibited high sensitivity, selectivity, and reproducibility, thereby serving as a powerful tool for the quality control and high-throughput detection of endotoxin in the food and pharmaceutical industries. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Pyroglyphid mites as a source of work-related allergens.

    PubMed

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

    2012-01-01

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

  6. Control of asthma triggers in indoor air with air cleaners: a modeling analysis.

    PubMed

    Myatt, Theodore A; Minegishi, Taeko; Allen, Joseph G; Macintosh, David L

    2008-08-06

    Reducing exposure to environmental agents indoors shown to increase asthma symptoms or lead to asthma exacerbations is an important component of a strategy to manage asthma for individuals. Numerous investigations have demonstrated that portable air cleaning devices can reduce concentrations of asthma triggers in indoor air; however, their benefits for breathing problems have not always been reproducible. The potential exposure benefits of whole house high efficiency in-duct air cleaners for sensitive subpopulations have yet to be evaluated. We used an indoor air quality modeling system (CONTAM) developed by NIST to examine peak and time-integrated concentrations of common asthma triggers present in indoor air over a year as a function of natural ventilation, portable air cleaners, and forced air ventilation equipped with conventional and high efficiency filtration systems. Emission rates for asthma triggers were based on experimental studies published in the scientific literature. Forced air systems with high efficiency filtration were found to provide the best control of asthma triggers: 30-55% lower cat allergen levels, 90-99% lower risk of respiratory infection through the inhalation route of exposure, 90-98% lower environmental tobacco smoke (ETS) levels, and 50-75% lower fungal spore levels than the other ventilation/filtration systems considered. These results indicate that the use of high efficiency in-duct air cleaners provide an effective means of controlling allergen levels not only in a single room, like a portable air cleaner, but the whole house. These findings are useful for evaluating potential benefits of high efficiency in-duct filtration systems for controlling exposure to asthma triggers indoors and for the design of trials of environmental interventions intended to evaluate their utility in practice.

  7. Airborne endotoxin in woodworking (joinery) shops.

    PubMed

    Harper, Martin; Andrew, Michael E

    2006-01-01

    Symptoms such as shortness of breath and cough have been noted in woodworking facilities even where wood dust itself is well-controlled. Suspicion has fallen on other possible contaminants in the workplace atmosphere, including bacterial endotoxin. A few studies have indicated potentially high endotoxin exposure with exposure to fresh wood in sawmills and in the production of fiberboard and chipboard, but fewer studies have been carried out on exposure to endotoxin in dry wood work, for example in joineries. A study of the endotoxin content of airborne wood dust samples from US woodworking facilities is presented, from the re-analysis of samples which previously had been taken to establish mass collection relationships between the IOM sampler, the closed-face 37 mm plastic cassette (CFC) sampler and the Button sampler. Endotoxin was strongly correlated with total dust, but the endotoxin content of a few fresh wood samples was found to be up to ten times higher per unit of wood dust than for dried-wood samples, and this difference was significant. No long-term time-weighted average sample exceeded the recommended limit value of 50 EU m(-3) (EU, endotoxin units)used in the Netherlands, although a number of the IOM samples came close (seven samples or 44% exceeded 20 EU m(-3)) and one short-term (48 minute) sample registered a high value of 73 EU m(-3). The geometric mean concentration from the IOM samples (11 EU m(-3)) is within the range of geometric means found from Australian joineries (3.7-60, combined: 24 EU m(-3)). In contrast, the corresponding values from the CFC (3.6 EU m(-3)), and the Button sampler (2.1 EU m(-3)) were much lower and no samples exceeded 20 EU m(-3). Endotoxin is likely only to be a significant problem in working with dried woods when associated with very high dust levels, where the wood dust itself is likely to be a cause for concern. The results from the few samples in this study where fresh wood was being worked were similar to results

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

    PubMed

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

    2014-01-01

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

  9. MitoQ administration prevents endotoxin-induced cardiac dysfunction.

    PubMed

    Supinski, G S; Murphy, M P; Callahan, L A

    2009-10-01

    Sepsis elicits severe alterations in cardiac function, impairing cardiac mitochondrial and pressure-generating capacity. Currently, there are no therapies to prevent sepsis-induced cardiac dysfunction. We tested the hypothesis that administration of a mitochondrially targeted antioxidant, 10-(6'-ubiquinonyl)-decyltriphenylphosphonium (MitoQ), would prevent endotoxin-induced reductions in cardiac mitochondrial and contractile function. Studies were performed on adult rodents (n = 52) given either saline, endotoxin (8 mg x kg(-1) x day(-1)), saline + MitoQ (500 microM), or both endotoxin and MitoQ. At 48 h animals were killed and hearts were removed for determination of either cardiac mitochondrial function (using polarography) or cardiac pressure generation (using the Langendorf technique). We found that endotoxin induced reductions in mitochondrial state 3 respiration rates, the respiratory control ratio, and ATP generation. Moreover, MitoQ administration prevented each of these endotoxin-induced abnormalities, P < 0.001. We also found that endotoxin produced reductions in cardiac pressure-generating capacity, reducing the systolic pressure-diastolic relationship. MitoQ also prevented endotoxin-induced reductions in cardiac pressure generation, P < 0.01. One potential link between mitochondrial and contractile dysfunction is caspase activation; we found that endotoxin increased cardiac levels of active caspases 9 and 3 (P < 0.001), while MitoQ prevented this increase (P < 0.01). These data demonstrate that MitoQ is a potent inhibitor of endotoxin-induced mitochondrial and cardiac abnormalities. We speculate that this agent may prove a novel therapy for sepsis-induced cardiac dysfunction.

  10. Contact allergens for armpits--allergenic fragrances specified on deodorants.

    PubMed

    Klaschka, Ursula

    2012-11-01

    According to the so-called "26 allergens rule" 26 supposedly allergenic fragrances must be specified on the containers of cosmetic products if they are present above 0.001% in leave-on products and, 0.01% in rinse-off products. This declaration is meant to inform the consumers of potential risks of skin sensitizers in the products. As many consumers of deodorants suffer from allergic or irritant contact dermatitis in the axillae, the presence of allergens in deodorants deserves special attention. The objective of this study was to find answers to the following questions: Does compulsory labeling lead to omission of strong allergenic fragrances in deodorants? Is there a difference in the use patterns of strong and weak allergens? What is the quantitative exposure to fragrances by deodorants? Is the situation in Germany different from other European countries? Is there a difference between deodorants for men and for women? I tested the implementation of the "26 allergens rule" and compiled which allergenic fragrances are specified on the containers of deodorants. Three market studies were conducted in Germany in 2008, 2010 and 2011. The labels of a total number of 374 deodorants were analyzed as to whether any of the "26 allergens" were listed. The frequency of each allergen in the deodorants was compared with results from previous studies by other authors. It was found that up to 83% of the deodorants contain at least one of the "26 allergens" and that up to 30% of all products contain strong allergens above the threshold for labeling (0.001% in the product). The most frequently listed allergens are medium or weak allergens. In comparison with other authors, the frequency of the "26 allergens" in products is slightly smaller in these recent studies for the German market. There is no significant difference between deodorants for men and women, as far as the labeling of the "26 allergens" is concerned. The results show that the mandatory labeling procedure as designed

  11. Field Studies Measuring the aerosolization of Endotoxin ...

    EPA Pesticide Factsheets

    Endotoxin is a component of the cell walls of Gram-negative bacteria and is known to be present in biosolids. Endotoxins have been shown to be a potent stimulator of the innate immune response causing airway irritation and shortness of breath. Class B biosolids are routinely applied to agricultural lands in the US to enhance soil properties and can be used as an alternative to chemical fertilizers. This study investigated the aerosolized endotoxin produced during the land application of Class B biosolids from various wastewater treatment plants on agricultural land and a concrete surface at two sites in Colorado, USA. Aerosolized endotoxin was captured using HiVol sampler fitted with glass fiber filter, polycarbonate filter cassette (both open and closed), and BioSampler impinger air samplers. Endotoxins were also measured in the bulk biosolids to allow for correlating bulk biosolids concentrations with aerosol emission rates. Endotoxin concentrations in biosolids, impinger solutions, and filter extracts were determined using the kinetic Limulus amebocyte lysate assay. Aerosolized endotoxin concentration was detected from all sites with levels ranging from 0.5 to 642 EU/m3. The four types of sampling apparatus were compared and the HiVol and open-faced cassette samplers used produced higher TWA measurements (EU/m3) than the impinger and closed cassette samplers. Ambient wind speed at the sites was found to be the variable best describing the results wit

  12. Moving Environmental Justice Indoors: Understanding Structural Influences on Residential Exposure Patterns in Low-Income Communities

    PubMed Central

    Zota, Ami R.; Fabian, M. Patricia; Chahine, Teresa; Julien, Rhona; Spengler, John D.; Levy, Jonathan I.

    2011-01-01

    Objectives. The indoor environment has not been fully incorporated into the environmental justice dialogue. To inform strategies to reduce disparities, we developed a framework to identify the individual and place-based drivers of indoor environment quality. Methods. We reviewed empirical evidence of socioeconomic disparities in indoor exposures and key determinants of these exposures for air pollutants, lead, allergens, and semivolatile organic compounds. We also used an indoor air quality model applied to multifamily housing to illustrate how nitrogen dioxide (NO2) and fine particulate matter (PM2.5) vary as a function of factors known to be influenced by socioeconomic status. Results. Indoor concentrations of multiple pollutants are elevated in low-socioeconomic status households. Differences in these exposures are driven by the combined influences of indoor sources, outdoor sources, physical structures, and residential activity patterns. Simulation models confirmed indoor sources’ importance in determining indoor NO2 and PM2.5 exposures and showed the influence of household-specific determinants. Conclusions. Both theoretical models and empirical evidence emphasized that disparities in indoor environmental exposure can be significant. Understanding key determinants of multiple indoor exposures can aid in developing policies to reduce these disparities. PMID:21836112

  13. Endotoxin Inhalation Alters Lung Development in Neonatal Mice

    PubMed Central

    Kulhankova, Katarina; George, Caroline L.S.; Kline, Joel N.; Darling, Melissa; Thorne, Peter S.

    2012-01-01

    Background Childhood asthma is a significant public health problem. Epidemiologic evidence suggests an association between childhood asthma exacerbations and early life exposure to environmental endotoxin. Although the pathogenesis of endotoxin-induced adult asthma is well studied, questions remain about the impact of environmental endotoxin on pulmonary responsiveness in early life. Methods We developed a murine model of neonatal/juvenile endotoxin exposures approximating those in young children and evaluated the lungs inflammatory and remodeling responses. Results Persistent lung inflammation induced by the inhalation of endotoxin in early life was demonstrated by the influx of inflammatory cells and pro-inflammatory mediators to the airways and resulted in abnormal alveolarization. Conclusions Results of this study advance the understanding of the impact early life endotoxin inhalation has on the lower airways, and demonstrates the importance of an experimental design that approximates environmental exposures as they occur in young children. PMID:22576659

  14. MitoQ administration prevents endotoxin-induced cardiac dysfunction

    PubMed Central

    Murphy, M. P.; Callahan, L. A.

    2009-01-01

    Sepsis elicits severe alterations in cardiac function, impairing cardiac mitochondrial and pressure-generating capacity. Currently, there are no therapies to prevent sepsis-induced cardiac dysfunction. We tested the hypothesis that administration of a mitochondrially targeted antioxidant, 10-(6′-ubiquinonyl)-decyltriphenylphosphonium (MitoQ), would prevent endotoxin-induced reductions in cardiac mitochondrial and contractile function. Studies were performed on adult rodents (n = 52) given either saline, endotoxin (8 mg·kg−1·day−1), saline + MitoQ (500 μM), or both endotoxin and MitoQ. At 48 h animals were killed and hearts were removed for determination of either cardiac mitochondrial function (using polarography) or cardiac pressure generation (using the Langendorf technique). We found that endotoxin induced reductions in mitochondrial state 3 respiration rates, the respiratory control ratio, and ATP generation. Moreover, MitoQ administration prevented each of these endotoxin-induced abnormalities, P < 0.001. We also found that endotoxin produced reductions in cardiac pressure-generating capacity, reducing the systolic pressure-diastolic relationship. MitoQ also prevented endotoxin-induced reductions in cardiac pressure generation, P < 0.01. One potential link between mitochondrial and contractile dysfunction is caspase activation; we found that endotoxin increased cardiac levels of active caspases 9 and 3 (P < 0.001), while MitoQ prevented this increase (P < 0.01). These data demonstrate that MitoQ is a potent inhibitor of endotoxin-induced mitochondrial and cardiac abnormalities. We speculate that this agent may prove a novel therapy for sepsis-induced cardiac dysfunction. PMID:19657095

  15. Navigating through the Jungle of Allergens: Features and Applications of Allergen Databases.

    PubMed

    Radauer, Christian

    2017-01-01

    The increasing number of available data on allergenic proteins demanded the establishment of structured, freely accessible allergen databases. In this review article, features and applications of 6 of the most widely used allergen databases are discussed. The WHO/IUIS Allergen Nomenclature Database is the official resource of allergen designations. Allergome is the most comprehensive collection of data on allergens and allergen sources. AllergenOnline is aimed at providing a peer-reviewed database of allergen sequences for prediction of allergenicity of proteins, such as those planned to be inserted into genetically modified crops. The Structural Database of Allergenic Proteins (SDAP) provides a database of allergen sequences, structures, and epitopes linked to bioinformatics tools for sequence analysis and comparison. The Immune Epitope Database (IEDB) is the largest repository of T-cell, B-cell, and major histocompatibility complex protein epitopes including epitopes of allergens. AllFam classifies allergens into families of evolutionarily related proteins using definitions from the Pfam protein family database. These databases contain mostly overlapping data, but also show differences in terms of their targeted users, the criteria for including allergens, data shown for each allergen, and the availability of bioinformatics tools. © 2017 S. Karger AG, Basel.

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

    PubMed

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

    2014-01-01

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

  17. Allantoin as a solid phase adsorbent for removing endotoxins.

    PubMed

    Vagenende, Vincent; Ching, Tim-Jang; Chua, Rui-Jing; Gagnon, Pete

    2013-10-04

    In this study we present a simple and robust method for removing endotoxins from protein solutions by using crystals of the small-molecule compound 2,5-dioxo-4-imidazolidinyl urea (allantoin) as a solid phase adsorbent. Allantoin crystalline powder is added to a protein solution at supersaturated concentrations, endotoxins bind and undissolved allantoin crystals with bound endotoxins are removed by filtration or centrifugation. This method removes an average of 99.98% endotoxin for 20 test proteins. The average protein recovery is ∼80%. Endotoxin binding is largely independent of pH, conductivity, reducing agent and various organic solvents. This is consistent with a hydrogen-bond based binding mechanism. Allantoin does not affect protein activity and stability, and the use of allantoin as a solid phase adsorbent provides better endotoxin removal than anion exchange, polymixin affinity and biological affinity methods for endotoxin clearance. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Control of asthma triggers in indoor air with air cleaners: a modeling analysis

    PubMed Central

    Myatt, Theodore A; Minegishi, Taeko; Allen, Joseph G; MacIntosh, David L

    2008-01-01

    Background Reducing exposure to environmental agents indoors shown to increase asthma symptoms or lead to asthma exacerbations is an important component of a strategy to manage asthma for individuals. Numerous investigations have demonstrated that portable air cleaning devices can reduce concentrations of asthma triggers in indoor air; however, their benefits for breathing problems have not always been reproducible. The potential exposure benefits of whole house high efficiency in-duct air cleaners for sensitive subpopulations have yet to be evaluated. Methods We used an indoor air quality modeling system (CONTAM) developed by NIST to examine peak and time-integrated concentrations of common asthma triggers present in indoor air over a year as a function of natural ventilation, portable air cleaners, and forced air ventilation equipped with conventional and high efficiency filtration systems. Emission rates for asthma triggers were based on experimental studies published in the scientific literature. Results Forced air systems with high efficiency filtration were found to provide the best control of asthma triggers: 30–55% lower cat allergen levels, 90–99% lower risk of respiratory infection through the inhalation route of exposure, 90–98% lower environmental tobacco smoke (ETS) levels, and 50–75% lower fungal spore levels than the other ventilation/filtration systems considered. These results indicate that the use of high efficiency in-duct air cleaners provide an effective means of controlling allergen levels not only in a single room, like a portable air cleaner, but the whole house. Conclusion These findings are useful for evaluating potential benefits of high efficiency in-duct filtration systems for controlling exposure to asthma triggers indoors and for the design of trials of environmental interventions intended to evaluate their utility in practice. PMID:18684328

  19. 484 Allergen Standardisation in Allergens and Allergoids—Challenges and Considerations

    PubMed Central

    Skinner, Murray; Bullimore, Alan; Hewings, Simon; Swan, Nicola

    2012-01-01

    Background The range of therapeutics and dosing schedules for allergen preparations and allergoids produced and used clinically are considerable. Standardisation of allergy immunotherapies is considered a positive step; however there are difficulties in identifying universal metrics for standardisation. Many advocate the use of major allergen content whilst others advocate total allergenicity. Additionally as a compounding argument, where major allergen is used, many disagree on what the major allergen is for certain species. Methods Major allergen content measurement allows a consistent recognised measure, and IgE responses of a serum pool are often dominated by IgE against major allergens. However issues such as specificity of different assays toward isoforms and other variants of single allergens often results in diverging allergen contents that can cause unexpected and misleading disparity. Other aspects that increase complication are the relevance to modified allergens, use of adjuvants and differing dosing regimes. Results The major allergen content of key products in different therapeutic formats has been measured. Conclusions This has been performed in conjunction with techniques such as total allergenicity, as allergy treatments and therapeutics require careful characterisation to allow supply of consistent, safe and efficacious products.

  20. Adherent endotoxin on dental implant surfaces: a reappraisal.

    PubMed

    Morra, Marco; Cassinelli, Clara; Bollati, Daniele; Cascardo, Giovanna; Bellanda, Marco

    2015-02-01

    Osteoimmunology is the crosstalk between cells from the immune and skeletal systems, suggesting a role of pro-inflammatory cytokines in the stimulation of osteoclast activity. Endotoxin or bacterial challenges to inflammatory cells are directly relevant to dental implant pathologies involving bone resorption, such as osseointegration failure and peri-implantitis. While the endotoxin amount on implant devices is regulated by standards, it is unknown whether commercially available dental implants elicit different levels of adherent-endotoxin stimulated cytokines. The objective of this work is to develop a model system and evaluate endotoxin-induced expression of pro-inflammatory cytokine genes relevant to osteoclast activation on commercially available dental implants. Murine J774-A1 macrophages were cultured on Ti disks with different level of lipopolysaccharide (LPS) contamination to define the time-course of the inflammatory response to endotoxin, as evaluated by reverse transcription polymerase chain reaction analysis. The developed protocol was then used to measure adherent endotoxin on commercially available packaged and sterile dental implants in the "as-implanted" condition. Results show that tested dental implants induce variable expression of endotoxin-stimulated genes, sometimes above the level expected to promote bone resorption in vivo. Results are unaffected by the specific surface treatment; rather, they likely reflect care in cleaning and packaging protocols. In conclusion, expression of genes that enhance osteoclast activity through endotoxin stimulation of inflammatory cells is widely different on commercially available dental implants. A reappraisal of the clinical impact of adherent endotoxins on dental (and bone) implant devices is required in light of increasing knowledge on crosstalk between cells from the immune and skeletal systems.

  1. Minor allergen patterns in birch pollen allergen products-A question of pollen?

    PubMed

    Zimmer, J; Döring, S; Strecker, D; Trösemeier, J H; Hanschmann, K M; Führer, F; Vieths, S; Kaul, S

    2017-08-01

    Contrary to the scientific differentiation between major and minor allergens, the regulatory framework controlling allergen products in the EU distinguishes relevant and non-relevant allergens. Given the lack of knowledge on their clinical relevance, minor allergens are usually not controlled by allergen product specifications. Especially, in birch pollen (BP) allergen products, minor allergens are commonly disregarded. To quantify three minor allergens in BP allergen products from different manufacturers and to assess the influence of the utilized BP on minor allergen patterns. Apart from common quality parameters such as Bet v 1 content, Bet v 4, Bet v 6 and Bet v 7 were quantified in 70 BP allergen product batches from six manufacturers, using ELISA systems developed in-house. Batch-to-batch variability was checked for agreement with a variability margin of 50%-200% from mean of the given batches for individual allergen content. Subsequently, minor allergen patterns were generated via multidimensional scaling and related to information on the pollen lots used in production of the respective product batches. Like the already established Bet v 4 ELISA, the ELISA systems for quantification of Bet v 6 and Bet v 7 were successfully validated. Differences in minor allergen content between products and batch-to-batch consistency were observed. Correlations between minor and major allergen content were low to moderate. About 20% of batches exceeded the variability margin for at least one minor allergen. Interestingly, these fluctuations could not in all cases be linked to the use of certain BP lots. The impact of the observed minor allergen variability on safety and efficacy of BP allergen products can currently not be estimated. As the described differences could only in few cases be related to the used pollen lots, it is evident that additional factors influence minor allergens in BP allergen products. © 2017 John Wiley & Sons Ltd.

  2. Expression, purification and characterization of Der f 27, a new allergen from dermatophagoides farinae

    PubMed Central

    Lin, Jianli; Li, Meng; Liu, Yulin; Jiang, Congli; Wu, Yulan; Wang, Yuanyuan; Gao, Anjian; Liu, Zhigang; Yang, Pingchang; Liu, Xiaoyu

    2015-01-01

    The house dust mite (HDM), Dermatophagoidesfarinae (D. farina), is one of the most important indoor allergen sources and a major elicitor of allergic asthma; itscharacterization is important in the diagnosis and immunotherapy of mite allergen-relevant diseases. This study aims to characterize a novel allergen, the D. farinae-derived serpin (Der f 27). In this study, the total RNA of D. farinae was extracted, and the Der f 27 gene was cloned and expressed. The allergenicity of recombinant Der f 27 protein was determined by enzyme-linked immunosorbent assay, and Western-blotting with the sera of asthma patients, and skin prick test (SPT) in allergic human subjects. A r-Der f 27 allergic asthma mouse model was established. The cloned Der f 27 gene has been presented at the Gene Bank with an accession number of KM009995. The IgE levels of r-Der f 27 in the serum from r-Der f 27 SPT positive allergic patients were 3 folds more than healthy subjects. The Der f 27 SPT positive ratewas 42.1% in 19 DM-SPT positive patients. Airway hyperresponsiveness, serum specific IgE, and levels of interleukin-4 in the spleen cell culture supernatant were significantly increased in allergic asthma mice sensitized to r-Der f 27. In conclusion, Der f 27 is a new subtype of house mite allergen. PMID:26328010

  3. Mediated effect of endotoxin and lead upon hepatic metabolism

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

    Kuttner, R.E.; Ebata, T.; Schumer, W.

    A test was made of the possibility that gram-negative bacterial cell wall lipopolysaccharides acted directly on key glucoregulatory enzymes in rat liver cytosol to cause the characteristic hypoglycemia of severe endotoxemia. Fasted male rats were sensitized to endotoxin by the simultaneous intravenous injection of lead acetate. The minimum systemic dosage of endotoxin necessary to perturb the normal pattern of hepatic glycolytic intermediates was determined by serial testing with diminishing dosages of endotoxin. The hepatocyte concentration of endotoxin was then calculated from this minimum dosage by use of literature data on the fraction of endotoxin delivered to liver cells after amore » systemic intravenous injection of radiochromium labeled lipopolysaccharides. Accepting a molecular weight of 118,000 daltons for the smallest endotoxin monomer capable of evoking a physiologic response, the molar amount of endotoxin present in 1 gram of hepatocytes was readily calculated. The concentration of glucoregulatory enzymes in parenchymal cells was then estimated from other literature sources. It was found that the amount of endotoxin in the hepatocytes was insufficient to combine directly with even 1 per cent of the quantity of a single key glucoregulatory enzyme in liver parenchyma. Since a one to one stoichiometric reaction between endotoxin and enzyme could not occur in the liver cytosol, a direct interaction mechanism between agonist and biocatalyst can be ruled out. It is concluded that bacterial endotoxin must act on hepatic glucoregulation by an indirect mechanism presumably based upon the release and operation of mediators.« less

  4. Food allergens: molecular and immunological aspects, allergen databases and cross-reactivity.

    PubMed

    Lorenz, Anne-Regine; Scheurer, Stephan; Vieths, Stefan

    2015-01-01

    The currently known food allergens are assigned to a relatively small number of protein families. Food allergens grouped into protein families share common functional and structural features that can be attributed to the allergenic potency and potential cross-reactivity of certain proteins. Molecular data, in terms of structural information, biochemical characteristics and clinical relevance for each known allergen, including isoforms and variants, are mainly compiled into four open-access databases. Allergens are designated according to defined criteria by the World Health Organization and the International Union of Immunological Societies Allergen Nomenclature Sub-committee. Food allergies are caused by primary sensitisation to the disease-eliciting food allergens (class I food allergen), or they can be elicited as a consequence of a primary sensitisation to inhalant allergens and subsequent IgE cross-reaction to homologous proteins in food (class II food allergens). Class I and class II allergens display different clinical significance in children and adults and are characterised by different molecular features. In line with this, high stability when exposed to gastrointestinal digestion and heat treatment is attributed to many class I food allergens that frequently induce severe reactions. The stability of a food allergen is determined by its molecular characteristics and can be influenced by structural (chemical) modifications due to thermal processing. Moreover, the immunogenicity and allergenicity of food allergens further depends on specific T cell and B cell epitopes. Although the T cell epitope pattern can be highly diverse for individual patients, several immuno-prominent T cell epitopes have been identified. Such conserved T cell epitopes and IgE cross-reactive B cell epitopes contribute to cross-reactivity between food allergens of the same family and to clinical cross-reactivity, similar to the birch pollen-food syndrome. © 2015 S. Karger AG, Basel.

  5. Effects of ceiling-mounted HEPA-UV air filters on airborne bacteria concentrations in an indoor therapy pool building.

    PubMed

    Kujundzic, Elmira; Zander, David A; Hernandez, Mark; Angenent, Largus T; Henderson, David E; Miller, Shelly L

    2005-02-01

    The purpose of this study was to assess the effectiveness of a new generation of high-volume, ceiling-mounted high-efficiency particulate air (HEPA)-ultraviolet (UV) air filters (HUVAFs) for their ability to remove or inactivate bacterial aerosol. In an environmentally controlled full-scale laboratory chamber (87 m3), and an indoor therapy pool building, the mitigation ability of air filters was assessed by comparing concentrations of total bacteria, culturable bacteria, and airborne endotoxin with and without the air filters operating under otherwise similar conditions. Controlled chamber tests with pure cultures of aerosolized Mycobacterium parafortuitum cells showed that the HUVAF unit tested provided an equivalent air-exchange rate of 11 hr(-1). Using this equivalent air-exchange rate as a design basis, three HUVAFs were installed in an indoor therapy pool building for bioaerosol mitigation, and their effectiveness was studied over a 2-year period. The HUVAFs reduced concentrations of culturable bacteria by 69 and 80% during monitoring periods executed in respective years. The HUVAFs reduced concentrations of total bacteria by 12 and 76% during the same monitoring period, respectively. Airborne endotoxin concentrations were not affected by the HUVAF operation.

  6. AllergenFP: allergenicity prediction by descriptor fingerprints.

    PubMed

    Dimitrov, Ivan; Naneva, Lyudmila; Doytchinova, Irini; Bangov, Ivan

    2014-03-15

    Allergenicity, like antigenicity and immunogenicity, is a property encoded linearly and non-linearly, and therefore the alignment-based approaches are not able to identify this property unambiguously. A novel alignment-free descriptor-based fingerprint approach is presented here and applied to identify allergens and non-allergens. The approach was implemented into a four step algorithm. Initially, the protein sequences are described by amino acid principal properties as hydrophobicity, size, relative abundance, helix and β-strand forming propensities. Then, the generated strings of different length are converted into vectors with equal length by auto- and cross-covariance (ACC). The vectors were transformed into binary fingerprints and compared in terms of Tanimoto coefficient. The approach was applied to a set of 2427 known allergens and 2427 non-allergens and identified correctly 88% of them with Matthews correlation coefficient of 0.759. The descriptor fingerprint approach presented here is universal. It could be applied for any classification problem in computational biology. The set of E-descriptors is able to capture the main structural and physicochemical properties of amino acids building the proteins. The ACC transformation overcomes the main problem in the alignment-based comparative studies arising from the different length of the aligned protein sequences. The conversion of protein ACC values into binary descriptor fingerprints allows similarity search and classification. The algorithm described in the present study was implemented in a specially designed Web site, named AllergenFP (FP stands for FingerPrint). AllergenFP is written in Python, with GIU in HTML. It is freely accessible at http://ddg-pharmfac.net/Allergen FP. idoytchinova@pharmfac.net or ivanbangov@shu-bg.net.

  7. Bla g 1 allergen levels in Zagreb area household dust.

    PubMed

    Prester, Ljerka; Macan, Jelena

    2011-03-01

    Cockroach allergy is a health problem in many parts of the world. In urban environments, indoor exposure to cockroach allergens involves a risk of asthma. The aim of this study was to measure the mass fraction of Bla g 1, a major allergen of the German cockroach (Blatella germanica) in 30 house samples, collected at random from Zagreb area households, Croatia. Dust samples were collected on cellulose filters by vacuuming living rooms floors. After extraction, Bla g 1 was detected using the commercial enzyme-linked immunosorbent assay (ELISA). Only four of the thirty households had detectable Bla g 1 levels, and only in one was its concentration higher than 2.0 U g(-1), the threshold associated with sensitisation. The Bla g 1 ELISA proved highly sensitive, with the detection limit of 0.12 U g(-1). The within- and between-assay imprecision was 8.9 % and 14.4 %, respectively, and accuracy 85 % to 120 %. Low Bla g 1 levels in the household dust support previously reported low prevalence of skin sensitisation to B. germanica among Zagreb residents. Further monitoring should reveal if there are differences in cockroach allergen exposure and sensitisation between households from other geographic areas in Croatia.

  8. Capillary Electrophoresis Chips for Fingerprinting Endotoxin Chemotypes and Subclasses.

    PubMed

    Kocsis, Béla; Makszin, Lilla; Kilár, Anikó; Péterfi, Zoltán; Kilár, Ferenc

    2017-01-01

    Endotoxins (lipopolysaccharides, LPS; lipooligosaccharides, LOS) are components of the envelope of Gram-negative bacteria. These molecules, responsible for both advantageous and harmful biological activity of these microorganisms, are highly immunogenic and directly involved in numerous bacterial diseases in humans, such as Gram-negative sepsis. The characterization of endotoxins is of importance, since their physiological and pathophysiological effects depend on their chemical structure. The differences among the LPS from different bacterial serotypes and their mutants include variations mainly within the composition and length or missing of their O-polysaccharide chains. Microchip electrophoretic methodology enables the structural characterization of LPS molecules from several bacteria and the quantitative evaluation of components of endotoxin extracts. The improved microchip electrophoretic method is based on the direct labeling of endotoxins by covalent binding of a fluorescent dye. The classification of the S-type LPSs can be done according to their electrophoretic profiles, which are characteristics of the respective bacterial strains. According to the number, distribution, and the relative amounts of components in an endotoxin extract, it is possible to differentiate between the S-type endotoxins from different Gram-negative bacterial strains. The microchip electrophoresis affords high-resolution separation of pure and partially purified (e.g., obtained from whole-cell lysate) S and R endotoxins. This microchip technique provides a new, standardizable, fast, and sensitive method for the detection of endotoxins and for the quantitative evaluation of components of an endotoxin extract.

  9. Recombinant allergens

    PubMed Central

    Jutel, Marek; Solarewicz-Madejek, Katarzyna; Smolinska, Sylwia

    2012-01-01

    Allergen specific immunotherapy (SIT) is the only known causative treatment of allergic diseases. Recombinant allergen-based vaccination strategies arose from a strong need to both to improve safety and enhance efficacy of SIT. In addition, new vaccines can be effective in allergies including food allergy or atopic dermatitis, which poorly respond to the current treatment with allergen extracts. A number of successful clinical studies with both wild-type and hypoallergenic derivatives of recombinant allergens vaccines have been reported for the last decade. They showed high efficacy and safety profile as well as very strong modulation of T and B cell responses to specific allergens. PMID:23095874

  10. Exposure to airborne culturable microorganisms and endotoxin in two Italian poultry slaughterhouses.

    PubMed

    Paba, Emilia; Chiominto, Alessandra; Marcelloni, Anna Maria; Proietto, Anna Rita; Sisto, Renata

    2014-01-01

    Even if slaughterhouses' workers handle large amounts of organic material and are potentially exposed to a wide range of biological agents, relatively little and not recent data are available. The main objective of this study was to characterize indoor concentrations of airborne bacteria, fungi, and endotoxin mod = Im (endotoxin∼Gram-negative*plant*filter) in two Italian poultry slaughterhouses. Air samples near air handling units inlets were also collected. Since there are not standardized protocols for endotoxin sampling and extraction procedures, an additional aim of the study was to compare the extraction efficiency of three different filter.. The study was also aimed at determining the correlation between concentrations of Gram-negative bacteria and endotoxin. In Plant A bacterial levels ranged from 17.5 to 2.6×10(3) CFU/m3. The highest concentrations were observed in evisceration area of chickens, between the automatic detachment of the neck and washing offal, and near birds coupling before hair-chilling. The highest mean value of Gram-negative (266.5 CFU/m3) was found near the washing offal of turkeys. In Plant B bacterial concentration ranged from 35 to 8×10(3) CFU/m3. The highest concentration. with the highest value of Gram-negative (248 CFU/m3), was found after defeathering. Fungal concentrations were overall lower than those found for bacteria (range: 0-205 CFU/m3 in Plant A and 0-146.2 CFU/m3 in Plant B). The microbial flora was dominated by Gram-negative and coagulase-negative staphylococci for bacteria and by species belonging to Cladosporium, Penicillium and Aspergillus genera for molds. The highest endotoxin concentrations were measured in washing offal for Plant A (range: 122.7-165.9 EU/m3) and after defeathering for Plant B (range: 0.83-38.85 EU/m3). In this study airborne microorganisms concentrations were lower than those found in similar occupational settings and below the occupational limits proposed by some authors. However, these

  11. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay. (a...

  12. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay. (a...

  13. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay. (a...

  14. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay. (a...

  15. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay. (a...

  16. A MECHANISM OF THE GLYCOGENOLYTIC ACTION OF BACTERIAL ENDOTOXIN

    PubMed Central

    Sanford, Jay P.; Barnett, Jack A.; Gott, Cora

    1960-01-01

    These experiments have demonstrated that liver glycogen may rise or fall after endotoxin administration, depending upon the antecedent diet and that total adrenalectomy followed by corticosteroid replacement abolishes the glycogenolytic effect of sublethal doses of endotoxin. It is concluded that the derangements of carbohydrate metabolism observed following the administration of sublethal quantities of bacterial endotoxin represent, not a direct hepatotoxic effect of endotoxin, but rather the passive consequence of epinephrine release. PMID:13746229

  17. Phospholipid imprinted polymers as selective endotoxin scavengers

    NASA Astrophysics Data System (ADS)

    Sulc, Robert; Szekely, Gyorgy; Shinde, Sudhirkumar; Wierzbicka, Celina; Vilela, Filipe; Bauer, David; Sellergren, Börje

    2017-03-01

    Herein we explore phospholipid imprinting as a means to design receptors for complex glycolipids comprising the toxic lipopolysaccharide endotoxin. A series of polymerizable bis-imidazolium and urea hosts were evaluated as cationic and neutral hosts for phosphates and phosphonates, the latter used as mimics of the phospholipid head groups. The bis-imidazolium hosts interacted with the guests in a cooperative manner leading to the presence of tight and well defined 1:2 ternary complexes. Optimized monomer combinations were subsequently used for imprinting of phosphatidic acid as an endotoxin dummy template. Presence of the aforementioned ternary complexes during polymerization resulted in imprinting of lipid dimers - the latter believed to crudely mimic the endotoxin Lipid A motif. The polymers were characterized with respect to template rebinding, binding affinity, capacity and common structural properties, leading to the identification of polymers which were thereafter subjected to an industrially validated endotoxin removal test. Two of the polymers were capable of removing endotoxin down to levels well below the accepted threshold (0.005 EU/mg API) in pharmaceutical production.

  18. Lipid biomarker analysis for the quantitative analysis of airborne microorganisms

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

    Macnaughton, S.J.; Jenkins, T.L.; Cormier, M.R.

    1997-08-01

    There is an ever increasing concern regarding the presence of airborne microbial contaminants within indoor air environments. Exposure to such biocontaminants can give rise to large numbers of different health effects including infectious diseases, allergenic responses and respiratory problems, Biocontaminants typically round in indoor air environments include bacteria, fungi, algae, protozoa and dust mites. Mycotoxins, endotoxins, pollens and residues of organisms are also known to cause adverse health effects. A quantitative detection/identification technique independent of culturability that assays both culturable and non culturable biomass including endotoxin is critical in defining risks from indoor air biocontamination. Traditionally, methods employed for themore » monitoring of microorganism numbers in indoor air environments involve classical culture based techniques and/or direct microscopic counting. It has been repeatedly documented that viable microorganism counts only account for between 0.1-10% of the total community detectable by direct counting. The classic viable microbiologic approach doe`s not provide accurate estimates of microbial fragments or other indoor air components that can act as antigens and induce or potentiate allergic responses. Although bioaerosol samplers are designed to damage the microbes as little as possible, microbial stress has been shown to result from air sampling, aerosolization and microbial collection. Higher collection efficiency results in greater cell damage while less cell damage often results in lower collection efficiency. Filtration can collect particulates at almost 100% efficiency, but captured microorganisms may become dehydrated and damaged resulting in non-culturability, however, the lipid biomarker assays described herein do not rely on cell culture. Lipids are components that are universally distributed throughout cells providing a means to assess independent of culturability.« less

  19. Food Allergens: Is There a Correlation between Stability to Digestion and Allergenicity?

    PubMed

    Bøgh, Katrine Lindholm; Madsen, Charlotte Bernhard

    2016-07-03

    Food allergy is a major health problem in the Western countries, affecting 3-8% of the population. It has not yet been established what makes a dietary protein a food allergen. Several characteristics have been proposed to be shared by food allergens. One of these is resistance to digestion. This paper reviews data from digestibility studies on purified food allergens and evaluates the predictive value of digestibility tests on the allergenic potential. We point out that food allergens do not necessarily resist digestion. We discuss how the choice of in vitro digestibility assay condition and the method used for detection of residual intact protein as well as fragments hereof may greatly influence the outcome as well as the interpretation of results. The finding that digests from food allergens may retain allergenicity, stresses the importance of using immunological assays for evaluating the allergenic potential of food allergen digestion products. Studies assessing the allergenicity of digestion products, by either IgE-binding, elicitation or sensitizing capacity, shows that digestion may abolish, decrease, have no effect, or even increase the allergenicity of food allergens. Therefore, the predictive value of the pepsin resistance test for assessing the allergenic potential of novel proteins can be questioned.

  20. Quality requirements for allergen extracts and allergoids for allergen immunotherapy.

    PubMed

    Zimmer, J; Bonertz, A; Vieths, S

    2017-12-01

    All allergen products for allergen immunotherapy currently marketed in the European Union are pharmaceutical preparations derived from allergen-containing source materials like pollens, mites and moulds. Especially this natural origin results in particular demands for the regulatory requirements governing allergen products. Furthermore, the development of regulatory requirements is complicated by the so far missing universal link between certain quality parameters, in particular biological potency, on the one hand and clinical efficacy on the other hand. As a consequence, each allergen product for specific immunotherapy has to be assessed individually for its quality, safety and efficacy. At the same time, biological potency of allergen products is most commonly determined using IgE inhibition assays based on human sera relative to product-specific in house references, ruling out full comparability of products from different manufacturers. This review article aims to summarize the current quality requirements for allergen products including the special requirements implemented for control of chemically modified allergen extracts (allergoids). Copyright © 2017 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

  1. Nanoparticle-allergen interactions mediate human allergic responses: protein corona characterization and cellular responses.

    PubMed

    Radauer-Preiml, Isabella; Andosch, Ancuela; Hawranek, Thomas; Luetz-Meindl, Ursula; Wiederstein, Markus; Horejs-Hoeck, Jutta; Himly, Martin; Boyles, Matthew; Duschl, Albert

    2016-01-16

    Engineered nanomaterials (ENMs) interact with different biomolecules as soon as they are in contact, resulting in the formation of a biomolecule 'corona'. Hence, the 'corona' defines the biological identity of the ENMs and could affect the response of the immune system to ENM exposure. With up to 40 % of the world population suffering from type I allergy, a possible modulation of allergen effects by binding to ENMs is highly relevant with respect to work place and consumer safety. Therefore, the aim of this present study was to gain an insight into the interactions of gold nanoparticles with different seasonally and perennially occurring outdoor and indoor allergens. Gold nanoparticles (AuNPs) were conjugated with the major allergens of birch pollen (Bet v 1), timothy grass pollen (Phl p 5) and house dust mite (Der p 1). The AuNP-allergen conjugates were characterized by means of TEM negative staining, dynamic light scattering (DLS), z-potential measurements and hyperspectral imaging. Furthermore, 3D models were constructed, based on the characterization data, to visualize the interaction between the allergens and the AuNPs surface. Differences in the activation of human basophil cells derived from birch/grass pollen- and house dust mite-allergic patients in response to free allergen and AuNP-allergen conjugates were determined using the basophil activation assay (BAT). Potential allergen corona replacement during BAT was controlled for using Western blotting. The protease activity of AuNP-Der p 1 conjugates compared to free Der p 1 was assessed, by an enzymatic activity assay and a cellular assay pertaining to lung type II alveolar epithelial cell tight junction integrity. The formation of a stable corona was found for all three allergens used. Our data suggest, that depending on the allergen, different effects are observed after binding to ENMs, including enhanced allergic responses against Der p 1 and also, for some patients, against Bet v 1. Moreover elevated

  2. Risks associated with endotoxins in feed additives produced by fermentation.

    PubMed

    Wallace, R John; Gropp, Jürgen; Dierick, Noël; Costa, Lucio G; Martelli, Giovanna; Brantom, Paul G; Bampidis, Vasileios; Renshaw, Derek W; Leng, Lubomir

    2016-01-15

    Increasingly, feed additives for livestock, such as amino acids and vitamins, are being produced by Gram-negative bacteria, particularly Escherichia coli. The potential therefore exists for animals, consumers and workers to be exposed to possibly harmful amounts of endotoxin from these products. The aim of this review was to assess the extent of the risk from endotoxins in feed additives and to calculate how such risk can be assessed from the properties of the additive. Livestock are frequently exposed to a relatively high content of endotoxin in the diet: no additional hazard to livestock would be anticipated if the endotoxin concentration of the feed additive falls in the same range as feedstuffs. Consumer exposure will be unaffected by the consumption of food derived from animals receiving endotoxin-containing feed, because the small concentrations of endotoxin absorbed do not accumulate in edible tissues. In contrast, workers processing a dusty additive may be exposed to hazardous amounts of endotoxin even if the endotoxin concentration of the product is low. A calculation method is proposed to compare the potential risk to the worker, based on the dusting potential, the endotoxin concentration and technical guidance of the European Food Safety Authority, with national exposure limits.

  3. Addressing endotoxin issues in bioengineered heparin.

    PubMed

    Suwan, Jiraporn; Torelli, Amanda; Onishi, Akihiro; Dordick, Jonathan S; Linhardt, Robert J

    2012-01-01

    Heparin is a widely used clinical anticoagulant that is prepared from pig intestine. A contamination of heparin in 2008 has led to a reexamination of animal-derived pharmaceuticals. A bioengineered heparin prepared by bacterial fermentation and chemical and enzymatic processing is currently under development. This study examines the challenges of reducing or removing endotoxins associated with this process that are necessary to proceed with preclinical in vivo evaluation of bioengineered heparin. The current process is assessed for endotoxin levels, and strategies are examined for endotoxin removal from polysaccharides and enzymes involved in this process. © 2012 International Union of Biochemistry and Molecular Biology, Inc.

  4. Duration of in vivo endotoxin tolerance in horses.

    PubMed

    Holcombe, Susan J; Jacobs, Carrie C; Cook, Vanessa L; Gandy, Jeffery C; Hauptman, Joseph G; Sordillo, Lorraine M

    2016-05-01

    Endotoxemia models are used to study mechanisms and treatments of early sepsis. Repeated endotoxin exposures induce periods of endotoxin tolerance, characterized by diminished proinflammatory responses to lipopolysaccharide (LPS) and modulated production of proinflammatory cytokines. Repeated measure designs using equine endotoxemia models are rarely performed, despite the advantages associated with reduced variability, because the altered responsiveness would confound study results and because the duration of equine endotoxin tolerance is unknown. We determined the interval of endotoxin tolerance, in vivo, in horses based on physical, clinicopathologic, and proinflammatory gene expression responses to repeated endotoxin exposures. Six horses received 30 ng/kg LPS in saline infused over 30 min. Behavior pain scores, physical examination parameters, and blood for complete blood count and proinflammatory gene expression were obtained at predetermined intervals for 24h. Horses received a total of 3 endotoxin exposures. The first exposure was LPS 1, followed 7 days later by LPS 7 or 14-21 days later by LPS 14-21. Lipopolysaccharide exposures were allocated in a randomized, crossover design. Lipopolysaccharide produced clinical and clinicopathologic signs of endotoxemia and increased expression of tumor necrosis factor alpha (TNFα), interleukin (IL)-6 and IL-8, P<0.001. Horses exhibited evidence of endotoxin tolerance following LPS 7 but not following LPS 14-21. Horses had significantly lower pain scores, heart rates, respiratory rates and duration of fever, after LPS 7 compared to LPS 1 and LPS 14-21, P<0.001, and expression of TNFα was lower in the whole blood of horses after LPS 7, P=0.05. Clinical parameters and TNFα gene expression were similar or slightly increased in horses following LPS 14-21 compared to measurements made in horses following LPS 1, suggesting that endotoxin tolerance had subsided. A minimum of 3 weeks between experiments is warranted if

  5. Extracorporeal Perfusion without Exogenous Anticoagulation: Its Protective Role in Endotoxin Shock.

    DTIC Science & Technology

    1982-02-19

    lethal effects of endotoxin . Group E: Heparinized dogs given endotoxin ; no perfusion. This group served to evaluate the effects of heparin on...recovery from endotoxin shock. Group F: Heparinized dogs perfused 90 minutes; then given endotoxin . This group served to assay the effects of exogenous...stable model and is preperfusion neces- sary to provide protection against the lethal effects of endotoxin ? The first series of experiments (Group B) were

  6. Inactivation of Escherichia coli Endotoxin by Soft Hydrothermal Processing▿

    PubMed Central

    Miyamoto, Toru; Okano, Shinya; Kasai, Noriyuki

    2009-01-01

    Bacterial endotoxins, also known as lipopolysaccharides, are a fever-producing by-product of gram-negative bacteria commonly known as pyrogens. It is essential to remove endotoxins from parenteral preparations since they have multiple injurious biological activities. Because of their strong heat resistance (e.g., requiring dry-heat sterilization at 250°C for 30 min) and the formation of various supramolecular aggregates, depyrogenation is more difficult than sterilization. We report here that soft hydrothermal processing, which has many advantages in safety and cost efficiency, is sufficient to assure complete depyrogenation by the inactivation of endotoxins. The endotoxin concentration in a sample was measured by using a chromogenic limulus method with an endotoxin-specific limulus reagent. The endotoxin concentration was calculated from a standard curve obtained using a serial dilution of a standard solution. We show that endotoxins were completely inactivated by soft hydrothermal processing at 130°C for 60 min or at 140°C for 30 min in the presence of a high steam saturation ratio or with a flow system. Moreover, it is easy to remove endotoxins from water by soft hydrothermal processing similarly at 130°C for 60 min or at 140°C for 30 min, without any requirement for ultrafiltration, nonselective adsorption with a hydrophobic adsorbent, or an anion exchanger. These findings indicate that soft hydrothermal processing, applied in the presence of a high steam saturation ratio or with a flow system, can inactivate endotoxins and may be useful for the depyrogenation of parenterals, including end products and medical devices that cannot be exposed to the high temperatures of dry heat treatments. PMID:19502435

  7. Modified Allergens for Immunotherapy.

    PubMed

    Satitsuksanoa, Pattraporn; Głobińska, Anna; Jansen, Kirstin; van de Veen, Willem; Akdis, Mübeccel

    2018-02-16

    During the past few decades, modified allergens have been developed for use in allergen-specific immunotherapy (AIT) with the aim to improve efficacy and reduce adverse effects. This review aims to provide an overview of the different types of modified allergens, their mechanism of action and their potential for improving AIT. In-depth research in the field of allergen modifications as well as the advance of recombinant DNA technology have paved the way for improved diagnosis and research on human allergic diseases. A wide range of structurally modified allergens has been generated including allergen peptides, chemically altered allergoids, adjuvant-coupled allergens, and nanoparticle-based allergy vaccines. These modified allergens show promise for the development of AIT regimens with improved safety and long-term efficacy. Certain modifications ensure reduced IgE reactivity and retained T cell reactivity, which facilities induction of immune tolerance to the allergen. To date, multiple clinical trials have been performed using modified allergens. Promising results were obtained for the modified cat, grass and birch pollen, and house dust mite allergens. The use of modified allergens holds promise for improving AIT efficacy and safety. There is however a need for larger clinical studies to reliably assess the added benefit for the patient of using modified allergens for AIT.

  8. Endotoxin detection--from limulus amebocyte lysate to recombinant factor C.

    PubMed

    Ding, Jeak Ling; Ho, Bow

    2010-01-01

    Gram negative bacterial endotoxin is a biological pyrogen that causes fever when introduced intravenously. The endotoxin, also known as lipopolysaccharide (LPS), is found in the outer membrane of Gram-negative bacteria. During Gram-negative sepsis, endotoxin stimulates host macrophages to release inflammatory cytokines. However, excessive inflammation causes multiple organ failure and death. Endotoxins, which are ubiquitous pathogenic molecules, are a bane to the pharmaceutical industry and healthcare community. Thus early and sensitive detection of endotoxin is crucial to prevent endotoxaemia. The limulus amebocyte lysate (LAL) has been widely used for ~30 years for the detection of endotoxin in the quality assurance of injectable drugs and medical devices. The LAL constitutes a cascade of serine proteases which are triggered by trace levels of endotoxin, culminating in a gel clot at the end of the reaction. The Factor C, which normally exists as a zymogen, is the primer of this coagulation cascade. In vivo, Factor C is the perfect biosensor, which alerts the horseshoe crab of the presence of a Gram-negative invader. The hemostatic end-point entraps the invader, killing it and limiting further infection. However, as an in vitro endotoxin detection tool, variations in the sensitivity and specificity of LAL to endotoxin, and the dwindling supply of horseshoe crabs are posing increasing challenges to the biotechnology industry. This has necessitated the innovation of an alternative test for endotoxin. Thus, Factor C became the obvious, albeit tricky target for the recombinant technology effort. This chapter documents the backwater of mining the natural blood lysate of the endangered species to the monumental effort of genetic engineering, to produce recombinant Factor C (rFC). The rFC is a 132 kDa molecule, which was produced as a proenzyme inducible by the presence of trace levels of endotoxin. The rFC forms the basis of the "PyroGene" kit, which is a novel micro

  9. Endotoxin inactivation by selected drinking water treatment oxidants.

    PubMed

    Anderson, William B; Mayfield, Colin I; Dixon, D George; Huck, Peter M

    2003-11-01

    Exposure to endotoxins in treated drinking water can occur through ingestion, dermal abrasions, inhalation of water vapor, intravenous injection or during dialysis. While the risks associated with endotoxin ingestion and entry through dermal abrasions are not well quantified, adverse effects of intravenous injection and dialysis are well known and some studies indicate that inhalation of moisture-laden air may impact human health. This study quantifies the inactivation of endotoxin derived from Escherichia coli O55:B5 by three substances used either as disinfectants or oxidants in drinking water treatment: chlorine, monochloramine and potassium permanganate. Inactivation rates were found to be 1.4, 1.0 and 0.7 endotoxin units (EU)/mL h, for free chlorine, potassium permanganate and monochloramine, respectively. These rates are relatively slow given that contact times in drinking water distribution systems are typically less than 48 h. While small amounts of endotoxin may be removed by oxidation the observed removals are much less than those provided by physical removal processes. The significance of this finding is important for dialysis considerations but is as yet unclear with regard to inhalation, as the risk of inhaling sufficient quantities of endotoxin-containing aerosolized water droplets to adversely affect human health has not yet been adequately quantified.

  10. Endotoxin contamination of apolipoprotein A-I: effect on macrophage proliferation--a cautionary tale.

    PubMed

    Jin, Xueting; Xu, Qing; Champion, Keith; Kruth, Howard S

    2015-05-01

    This technical report addresses the problem of endotoxin contamination of apolipoprotein reagents. Using a bromodeoxyuridine incorporation cell proliferation assay, we observed that human plasma ApoA-I as low as 1 μg/ml resulted in a >90% inhibition in macrophage proliferation. However, not all ApoA-I from different sources showed this effect. We considered the possibility that endotoxin contamination of the apolipoproteins contributed to the differential inhibition of macrophage cell proliferation. Endotoxin alone very potently inhibited macrophage proliferation (0.1 ng/ml inhibited macrophage proliferation>90%). Measurement of endotoxin levels in the apolipoprotein products, including an analysis of free versus total endotoxin, the latter which included endotoxin that was masked due to binding to protein, suggested that free endotoxin mediated inhibition of macrophage proliferation. Despite the use of an advanced endotoxin removal procedure and agents commonly used to inhibit endotoxin action, the potency of endotoxin precluded successful elimination of endotoxin effect. Our findings show that endotoxin contamination can significantly influence apparent apolipoprotein-mediated cell effects (or effects of any other biological products), especially when these products are tested on highly endotoxin-sensitive cells, such as macrophages. Published by Elsevier Ireland Ltd.

  11. Quantification of endotoxins in infected root canals and acute apical abscess exudates: monitoring the effectiveness of root canal procedures in the reduction of endotoxins.

    PubMed

    Sousa, Ezilmara L R; Martinho, Frederico C; Nascimento, Gustavo G; Leite, Fabio R M; Gomes, Brenda P F A

    2014-02-01

    This clinical study was conducted to measure the endotoxin levels in infected root canals (RCs) and exudates related to acute apical abscesses (AAAs). In addition, the effectiveness of RC procedures in reducing the endotoxin levels in RCs was monitored. Paired samples of infected RCs and exudates from AAAs were collected from 10 subjects by using paper points. RCs samples were collected before (RCS1) and after chemomechanical preparation (CMP) (RCS2), after 17% EDTA (RCS3), and after 30 days of intracanal medication (Ca[OH]2 + chlorhexidine) (RCS4). A turbidimetric kinetic limulus amebocyte lysate assay was used for the measurement of endotoxins. Endotoxins were detected in 100% of the baseline samples of AAAs and RCs (RCS1) with median values of 175 EU/mL and 41.5 EU/mL, respectively (P < .05). After CMP (RCS2), endotoxins were reduced to a median value of 0.54 EU/mL (P < .05). Subsequent irrigation with EDTA (RCS3) failed to present a significant effectiveness in reducing the endotoxin levels (median= 0.37 EU/mL) (P = .07). However, intracanal medication for 30 days (RCS4) reduced endotoxins to median values of 0.03 EU/mL (P < .01). The present study revealed a strong association between the high levels of endotoxins found in AAAs and RCs collected from the same tooth. Moreover, the effectiveness of CMP in reducing the endotoxin levels from RCs in acute endodontic infection was improved by the use of RC medication. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Detoxifying Escherichia coli for endotoxin-free production of recombinant proteins.

    PubMed

    Mamat, Uwe; Wilke, Kathleen; Bramhill, David; Schromm, Andra Beate; Lindner, Buko; Kohl, Thomas Andreas; Corchero, José Luis; Villaverde, Antonio; Schaffer, Lana; Head, Steven Robert; Souvignier, Chad; Meredith, Timothy Charles; Woodard, Ronald Wesley

    2015-04-16

    Lipopolysaccharide (LPS), also referred to as endotoxin, is the major constituent of the outer leaflet of the outer membrane of virtually all Gram-negative bacteria. The lipid A moiety, which anchors the LPS molecule to the outer membrane, acts as a potent agonist for Toll-like receptor 4/myeloid differentiation factor 2-mediated pro-inflammatory activity in mammals and, thus, represents the endotoxic principle of LPS. Recombinant proteins, commonly manufactured in Escherichia coli, are generally contaminated with endotoxin. Removal of bacterial endotoxin from recombinant therapeutic proteins is a challenging and expensive process that has been necessary to ensure the safety of the final product. As an alternative strategy for common endotoxin removal methods, we have developed a series of E. coli strains that are able to grow and express recombinant proteins with the endotoxin precursor lipid IVA as the only LPS-related molecule in their outer membranes. Lipid IVA does not trigger an endotoxic response in humans typical of bacterial LPS chemotypes. Hence the engineered cells themselves, and the purified proteins expressed within these cells display extremely low endotoxin levels. This paper describes the preparation and characterization of endotoxin-free E. coli strains, and demonstrates the direct production of recombinant proteins with negligible endotoxin contamination.

  13. General effect of endotoxin on glucocorticoid receptors in mammalian tissues

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

    Stith, R.D.; McCallum, R.E.

    Considering the ubiquitous nature of glucocorticoid actions and the fact that endotoxin inhibits glucocorticoid action in the liver, we proposed to examine whether endotoxin affected extrahepatic actions of glucocorticoids. Fasted C57BL/6J mice were injected intraperitoneally with endotoxin (LD50) at 0800 and were killed 6 h later. Control mice were injected with an equal volume of saline. /sup 3/H-dexamethasone binding, measured by a new cytosol exchange assay utilizing molybdate plus dithiothreitol, in liver, kidney, skeletal muscle, spleen, lung, and heart tissue was significantly lower in treated than in control mice. The equilibrium dissociation constants were not significantly different, but the numbermore » of available binding sites in each tissue was reduced by endotoxin treatment. Phosphoenolpyruvate carboxykinase activity was significantly reduced in liver but not in kidney. Endotoxin treatment lowered glycogen content in liver but not in skeletal muscle. The reduction observed in the a form of liver glycogen synthase due to endotoxin was not seen in skeletal muscle glycogen synthase a. These data support the proposal that endotoxin or a mediator of its action inhibits systemic glucocorticoid action. The results also emphasize the central role of the liver in the metabolic disturbances of the endotoxin-treated mouse.« less

  14. Endotoxin-Induced Structural Transformations in Liquid Crystalline Droplets

    NASA Astrophysics Data System (ADS)

    Lin, I.-Hsin; Miller, Daniel S.; Bertics, Paul J.; Murphy, Christopher J.; de Pablo, Juan J.; Abbott, Nicholas L.

    2011-06-01

    The ordering of liquid crystals (LCs) is known to be influenced by surfaces and contaminants. Here, we report that picogram per milliliter concentrations of endotoxin in water trigger ordering transitions in micrometer-size LC droplets. The ordering transitions, which occur at surface concentrations of endotoxin that are less than 10-5 Langmuir, are not due to adsorbate-induced changes in the interfacial energy of the LC. The sensitivity of the LC to endotoxin was measured to change by six orders of magnitude with the geometry of the LC (droplet versus slab), supporting the hypothesis that interactions of endotoxin with topological defects in the LC mediate the response of the droplets. The LC ordering transitions depend strongly on glycophospholipid structure and provide new designs for responsive soft matter.

  15. Allergens retained in clothing.

    PubMed

    Nedorost, Susan; Kessler, Margaret; McCormick, Thomas

    2007-12-01

    Some patients state compliance with avoidance of identified allergens, yet have persistent dermatitis in areas under tight-fitting clothing. To analyze a series of such cases to identify allergens most likely retained in clothing. Review of contact dermatitis clinic cases and identification of type and formula weight of allergens involved. High-formula-weight allergens and allergens present in medicament ointments are difficult to dissolve in laundry detergent and water and may be retained in clothing. Retention of allergens in clothing, even after washing, may explain recalcitrant dermatitis in a patient who states compliance with avoidance of a seemingly relevant allergen. Dermatologists should consider the possibility of allergen retention in clothing whenever a patient has only partial clearing after at least 1 month of attempted compliance with avoidance of identified allergens. Purchase of new clothing may be required to clear allergic contact dermatitis in this situation.

  16. Indoor environmental exposures for children with asthma enrolled in the HEAL study, post-Katrina New Orleans.

    PubMed

    Grimsley, L Faye; Chulada, Patricia C; Kennedy, Suzanne; White, LuAnn; Wildfire, Jeremy; Cohn, Richard D; Mitchell, Herman; Thornton, Eleanor; El-Dahr, Jane; Mvula, Mosanda M; Sterling, Yvonne; Martin, William J; Stephens, Kevin U; Lichtveld, Maureen

    2012-11-01

    Rain and flooding from Hurricane Katrina resulted in widespread growth of mold and bacteria and production of allergens in New Orleans, Louisiana, which may have led to increased exposures and morbidity in children with asthma. The goal of the Head-off Environmental Asthma in Louisiana (HEAL) study was to characterize post-Katrina exposures to mold and allergens in children with asthma. The homes of 182 children with asthma in New Orleans and surrounding parishes were evaluated by visual inspection, temperature and moisture measurements, and air and dust sampling. Air was collected using vacuum-pump spore traps and analyzed for > 30 mold taxa using bright field microscopy. Dust was collected from the children's beds and bedroom floors and analyzed for mouse (Mus m 1), dust mite (Der p 1), cockroach (Bla g 1), and mold (Alternaria mix) allergens using ELISA. More than half (62%) of the children were living in homes that had been damaged by rain, flooding, or both. Geometric mean indoor and outdoor airborne mold levels were 501 and 3,958 spores/m3, respectively. Alternaria antigen was detected in dust from 98% of homes, with 58% having concentrations > 10 µg/g. Mus m 1, Der p 1, and Bla g 1 were detected in 60%, 35%, and 20% of homes, respectively, at low mean concentrations. Except for Alternaria antigen in dust, concentrations of airborne mold (ratio of indoor to outdoor mold) and dust allergens in the homes of HEAL children were lower than measurements found in other studies, possibly because of extensive post-Katrina mold remediation and renovations, or because children moved into cleaner homes upon returning to New Orleans.

  17. Antigenic Determinants of the Bilobal Cockroach Allergen Bla g 2*

    PubMed Central

    Woodfolk, Judith A.; Glesner, Jill; Wright, Paul W.; Kepley, Christopher L.; Li, Mi; Himly, Martin; Muehling, Lyndsey M.; Gustchina, Alla; Wlodawer, Alexander; Chapman, Martin D.; Pomés, Anna

    2016-01-01

    Bla g 2 is a major indoor cockroach allergen associated with the development of asthma. Antigenic determinants on Bla g 2 were analyzed by mutagenesis based on the structure of the allergen alone and in complex with monoclonal antibodies that interfere with IgE antibody binding. The structural analysis revealed mechanisms of allergen-antibody recognition through cation-π interactions. Single and multiple Bla g 2 mutants were expressed in Pichia pastoris and purified. The triple mutant K132A/K251A/F162Y showed an ∼100-fold reduced capacity to bind IgE, while preserving the native molecular fold, as proven by x-ray crystallography. This mutant was still able to induce mast cell release. T-cell responses were assessed by analyzing Th1/Th2 cytokine production and the CD4+ T-cell phenotype in peripheral blood mononuclear cell cultures. Although T-cell activating capacity was similar for the KKF mutant and Bla g 2 based on CD25 expression, the KKF mutant was a weaker inducer of the Th2 cytokine IL-13. Furthermore, this mutant induced IL-10 from a non-T-cell source at higher levels that those induced by Bla g 2. Our findings demonstrate that a rational design of site-directed mutagenesis was effective in producing a mutant with only 3 amino acid substitutions that maintained the same fold as wild type Bla g 2. These residues, which were involved in IgE antibody binding, endowed Bla g 2 with a T-cell modulatory capacity. The antigenic analysis of Bla g 2 will be useful for the subsequent development of recombinant allergen vaccines. PMID:26644466

  18. Exposure to airborne microorganisms, dust and endotoxin during processing of valerian roots on farms.

    PubMed

    Skórska, Czesława; Sitkowska, Jolanta; Krysińska-Traczyk, Ewa; Cholewa, Grazyna; Dutkiewicz, Jacek

    2005-01-01

    The aim of this study was to determine the levels of microorganisms, dust and endotoxin in the air during various stages of valerian (Valeriana officinalis) roots processing by herb farmers and to examine the species composition of airborne microflora. Air samples were collected on glass fibre filters by use of personal samplers on 15 farms owned by valerian cultivating farmers, located in Lublin province (eastern Poland). The concentrations of total viable microorganisms (bacteria + fungi) in the air showed a marked variability and were within a range of 0.95-7,966.6 x 10(3) cfu/m (3). Though median was relatively low (10.75 x 10(3) cfu/m (3)), on 4 farms the concentrations exceeded the level of 10(5) cfu/m (3) and on 1 farm the level of 10(6) cfu/m (3). During the processing of valerian roots, distinct changes could be observed in the composition of airborne microflora. In the first stages of processing, the freshly dug and washed roots until shaking in the drying room, the most numerous were Gram-negative bacteria of the family Pseudomonadaceae (mostly Stenotrophomonas maltophilia, Pseudomonas chlororaphis and Pseudomonas fluorescens). After drying, the dominant organisms were thermo-resistant endospore-forming bacilli (Bacillus spp.) and fungi, among which prevailed Aspergillus fumigatus. Altogether, 29 species or genera of bacteria and 19 species or genera of fungi were identified in the farm air during valerian processing, of these, 10 and 12 species or genera respectively were reported as having allergenic and/or immunotoxic properties. The concentrations of airborne dust and endotoxin on the examined farms were very large and ranged from 10.0-776.7 mg/m (3), and from 0.15-24,448.2 microg/m (3), respectively (medians 198.3 mg/m (3) and 40.48 microg/m (3)). In conclusion, farmers cultivating valerian could be exposed during processing of valerian roots to large concentrations of airborne microorganisms, dust and endotoxin posing a risk of work

  19. Detection of Endotoxin Contamination of Graphene Based Materials Using the TNF-α Expression Test and Guidelines for Endotoxin-Free Graphene Oxide Production.

    PubMed

    Mukherjee, Sourav P; Lozano, Neus; Kucki, Melanie; Del Rio-Castillo, Antonio E; Newman, Leon; Vázquez, Ester; Kostarelos, Kostas; Wick, Peter; Fadeel, Bengt

    2016-01-01

    Nanomaterials may be contaminated with bacterial endotoxin during production and handling, which may confound toxicological testing of these materials, not least when assessing for immunotoxicity. In the present study, we evaluated the conventional Limulus amebocyte lysate (LAL) assay for endotoxin detection in graphene based material (GBM) samples, including graphene oxide (GO) and few-layered graphene (FLG). Our results showed that some GO samples interfered with various formats of the LAL assay. To overcome this problem, we developed a TNF-α expression test (TET) using primary human monocyte-derived macrophages incubated in the presence or absence of the endotoxin inhibitor, polymyxin B sulfate, and found that this assay, performed with non-cytotoxic doses of the GBM samples, enabled unequivocal detection of endotoxin with a sensitivity that is comparable to the LAL assay. FLG also triggered TNF-α production in the presence of the LPS inhibitor, pointing to an intrinsic pro-inflammatory effect. Finally, we present guidelines for the preparation of endotoxin-free GO, validated by using the TET.

  20. Endotoxin contamination: a key element in the interpretation of nanosafety studies.

    PubMed

    Li, Yang; Boraschi, Diana

    2016-02-01

    The study of toxicity and potential risks of engineered nanoparticles is of particular importance in nanomedicine. Endotoxin, a common contaminant of bacterial origin, has biological effects that can mask the true biological effects of nanoparticles, if its presence is overlooked. In this review, we report the features of nanoparticle contamination by endotoxin, and the different biological effects of endotoxin-contaminated nanoparticles. We will describe different methods for endotoxin detection applied to nanoparticles, and discuss their pros and cons. Eventually, we describe various methods for eliminating endotoxin contamination in nanoparticles. Although there is no universal technique for efficiently removing endotoxin from nanoparticles, specific solutions can be found case by case, which can allow us to perform nanosafety studies in biologically relevant conditions.

  1. Endotoxin in Size-Separated Metal Working Fluid Aerosol Particles.

    PubMed

    Dahlman-Höglund, Anna; Lindgren, Åsa; Mattsby-Baltzer, Inger

    2016-08-01

    Patients with airway symptoms working in metal working industries are increasing, despite efforts to improve the environmental air surrounding the machines. Our aim was to analyse the amount of endotoxin in size-separated airborne particles of metal working fluid (MWF) aerosol, by using the personal sampler Sioutas cascade impactor, to compare filter types, and to compare the concentration of airborne endotoxin to that of the corresponding MWFs. In a pilot field study, aerosols were collected in two separate machine halls on totally 10 occasions, using glass fibre and polytetrafluoroethylene (PTFE) filters in parallel at each station. Airborne endotoxin was distributed over all size fractions. While a major part was found in the largest size fraction (72%, 2.5-10 µm), up to 8% of the airborne endotoxin was detected in the smallest size fraction (<0.25 µm). Comparing the efficiency of the filter types, a significantly higher median endotoxin level was found with glass fibres filters collecting the largest particle-size fraction (1.2-fold) and with PTFE filters collecting the smallest ones (5-fold). The levels of endotoxin in the size-separated airborne particle fractions correlated to those of the MWFs supporting the aerosol-generating machines. Our study indicates that a significant part of inhalable aerosols of MWFs consists of endotoxin-containing particles below the size of intact bacteria, and thus small enough to readily reach the deepest part of the lung. Combined with other chemical irritants of the MWF, exposure to MWF aerosols containing endotoxin pose a risk to respiratory health problems. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  2. Ultrasensitive detection of endotoxins using computationally designed nanoMIPs.

    PubMed

    Altintas, Zeynep; Abdin, Mohammed J; Tothill, Alexander M; Karim, Kal; Tothill, Ibtisam E

    2016-09-07

    Novel molecularly imprinted polymer nanoparticles (nanoMIPs) were designed for endotoxin from Escherichia coli 0111:B4, using computational modeling. The screening process based on binding energy between endotoxin and each monomer was performed with 21 commonly used monomers, resulting in the selection of itaconic acid, methacrylic acid and acrylamide as functional monomers due to their strong binding interaction with the endotoxin template. The nanoMIPs were successfully synthesized with functional groups on the outer surface to aid in the immobilization onto sensor surface. The solid phase photopolymerization approach used for the synthesis of nanoMIPs ranging from 200 to 235 nm in diameter. The limit of detection and KD were significantly improved when endotoxin samples were prepared using a novel triethylamine method. This improved the efficiency of gold nanoparticle functionalization by targeting the subunits of the endotoxin. Compared to the vancomycin MIP control, the endotoxin MIPs displayed outstanding affinity and selectivity towards the endotoxin with KD values in the range of 4.4-5.3 × 10(-10) M, with limits of detection of 0.44 ± 0.02 ng mL(-1) as determined by surface plasmon resonance (SPR) sensor when itaconic acid was used as the functional monomer. The MIP surface can be regenerated >30 times without significant loss of binding activity making this approach highly cost effective for expensive analyte templates. The combination of molecular modeling and solid phase synthesis enabled the successful synthesis of nanoMIPs capable of recognition and ultrasensitive detection of endotoxins using the highly sensitive SPR biosensor with triethylamine method. Copyright © 2016 Elsevier B.V. All rights reserved.

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

    PubMed

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

    2006-12-01

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

  4. Vapor Pressure and Predicted Stability of American Contact Dermatitis Society Core Allergens

    PubMed Central

    Jou, Paul C.; Siegel, Paul D.; Warshaw, Erin M.

    2018-01-01

    Background Accurate patch testing is reliant on proper preparation of patch test allergens. The stability of patch test allergens is dependent on several factors including vapor pressure (VP). Objective This investigation reviews the VP of American Contact Dermatitis Society Core Allergens and compares stability predictions based on VP with those established through clinical testing. Methods Standard references were accessed for determining VP in millimeters of mercury and associated temperature in degrees celsius. If multiple values were listed, VP at temperatures that most approximate indoor storage conditions (20°C and 25°C) were chosen. For mixes, the individual component with the highest VP was chosen as the overall VP, assuming that the most volatile substance would evaporate first. Antigens were grouped into low (≤0.001 mm Hg), moderate (<1 to >0.001 mm Hg), and high (≥1 mm Hg) volatility using arbitrary cutoff values. Conclusions This review is consistent with previously reported data on formaldehyde, acrylates, and fragrance material instability. Given lack of testing data, VP can be useful in predicting patch test compound stability. Measures such as air-tight multidose reagent containers, sealed single-application dispensers, preparation of patches immediately before application, and storage at lower temperatures may remedy some of these issues. PMID:27427821

  5. Bacterial endotoxin in the endometrium and its clinical significance in reproduction.

    PubMed

    Kamiyama, Shigeru; Teruya, Yoko; Nohara, Makoto; Kanazawa, Koji

    2004-10-01

    Bacterial endotoxin was detected in menstrual effluent from infertile women. Endometrial endotoxin appears to influence reproductive process because the pregnancy rate after IVF-ET was significantly associated with an endotoxin level.

  6. Fluorescent nanodiamonds as highly stable biomarker for endotoxin verification

    NASA Astrophysics Data System (ADS)

    Bergmann, Thorsten; Burg, Jan Michael; Lilholt, Maria; Maeder, Ulf; Beer, Sebastian; Salzig, Denise; Ebrahimi, Mehrdad; Czermak, Peter; Fiebich, Martin

    2012-03-01

    Fluorescent nanodiamonds (ND) provide advantageous properties as a fluorescent biomarker for in vitro and in vivo studies. The maximum fluorescence occurs around 700 nm, they do not show photobleaching or blinking and seem to be nontoxic. After a pretreatment with strong acid fluorescent ND can be functionalized and coupled to endotoxin. Endotoxin is a decay product of bacteria and causes strong immune reactions. Therefore endotoxin has to be removed for most applications. An effective removal procedure is membrane filtration. The endotoxin, coupled to fluorescent ND can be visualized by using confocal microscopy which allows the investigation of the separation mechanisms of the filtration process within the membranes.

  7. Fish Allergens at a Glance: Variable Allergenicity of Parvalbumins, the Major Fish Allergens

    PubMed Central

    Kuehn, Annette; Swoboda, Ines; Arumugam, Karthik; Hilger, Christiane; Hentges, François

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand, some individuals have IgE antibodies directed against unique, species-specific parvalbumin epitopes, and these patients show clinical symptoms only with certain fish species. Furthermore, different parvalbumin isoforms and isoallergens are present in the same fish and might display variable allergenicity. This was shown for salmon homologs, where only a single parvalbumin (beta-1) isoform was identified as allergen in specific patients. In addition to the parvalbumins, several other fish proteins, enolases, aldolases, and fish gelatin, seem to be important allergens. New clinical and molecular insights advanced the knowledge and understanding of fish allergy in the last years. These findings were useful for the advancement of the IgE-based diagnosis and also for the management of fish allergies consisting of advice and treatment of fish-allergic patients. PMID:24795722

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  10. Endotoxin Contamination of Apolipoprotein A-I: Effect on Macrophage Proliferation – A Cautionary Tale

    PubMed Central

    Jin, Xueting; Xu, Qing; Champion, Keith; Kruth, Howard S.

    2015-01-01

    This technical report addresses the problem of endotoxin contamination of apolipoprotein reagents. Using a bromodeoxyuridine incorporation cell proliferation assay, we observed that human plasma ApoA-I as low as 1 μg/ml resulted in a >90% inhibition in macrophage proliferation. However, not all ApoA-I from different sources showed this effect. We considered the possibility that endotoxin contamination of the apolipoproteins contributed to the differential inhibition of macrophage cell proliferation. Endotoxin alone very potently inhibited macrophage proliferation (0.1 ng/ml inhibited macrophage proliferation >90%). Measurement of endotoxin levels in the apolipoprotein products, including an analysis of free versus total endotoxin, the latter which included endotoxin that was masked due to binding to protein, suggested that free endotoxin mediated inhibition of macrophage proliferation. Despite the use of an advanced endotoxin removal procedure and agents commonly used to inhibit endotoxin action, the potency of endotoxin precluded successful elimination of endotoxin effect. Our findings show that endotoxin contamination can significantly influence apparent apolipoprotein-mediated cell effects (or effects of any other biological products), especially when these products are tested on highly endotoxin-sensitive cells, such as macrophages. PMID:25778625

  11. Allergens in veterinary medicine.

    PubMed

    Mueller, R S; Janda, J; Jensen-Jarolim, E; Rhyner, C; Marti, E

    2016-01-01

    Allergic diseases in animals are increasingly gaining importance in veterinary practice and as research models. For intradermal testing and allergen immunotherapy, a good knowledge of relevant allergens for the individual species is of great importance. Currently, the knowledge about relevant veterinary allergens is based on sensitization rates identified by intradermal testing or serum testing for allergen-specific IgE; crude extracts are the basis for most evaluations. Only a few studies provide evidence about the molecular structure of (particularly) dust mite, insect and mould allergens in dogs and horses, respectively. In those species, some major allergens differ from those in humans. This position paper summarizes the current knowledge about relevant allergens in dogs, cats and horses. © 2015 The Authors Allergy Published by John Wiley & Sons Ltd.

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

    PubMed

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

    2015-07-01

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

  13. Relationships among indoor, outdoor, and personal airborne Japanese cedar pollen counts.

    PubMed

    Yamamoto, Naomichi; Matsuki, Yuuki; Yokoyama, Hiromichi; Matsuki, Hideaki

    2015-01-01

    Japanese cedar pollinosis (JCP) is an important illness caused by the inhalation of airborne allergenic cedar pollens, which are dispersed in the early spring throughout the Japanese islands. However, associations between pollen exposures and the prevalence or severity of allergic symptoms are largely unknown, due to a lack of understanding regarding personal pollen exposures in relation to indoor and outdoor concentrations. This study aims to examine the relationships among indoor, outdoor, and personal airborne Japanese cedar pollen counts. We conducted a 4-year monitoring campaign to quantify indoor, outdoor, and personal airborne cedar pollen counts, where the personal passive settling sampler that has been previously validated against a volumetric sampler was used to count airborne pollen grains. A total of 256 sets of indoor, outdoor, and personal samples (768 samples) were collected from 9 subjects. Medians of the seasonally-integrated indoor-to-outdoor, personal-to-outdoor, and personal-to-indoor ratios of airborne pollen counts measured for 9 subjects were 0.08, 0.10, and 1.19, respectively. A greater correlation was observed between the personal and indoor counts (r = 0.89) than between the personal and outdoor counts (r = 0.71), suggesting a potential inaccuracy in the use of outdoor counts as a basis for estimating personal exposures. The personal pollen counts differed substantially among the human subjects (49% geometric coefficient of variation), in part due to the variability in the indoor counts that have been found as major determinants of the personal pollen counts. The findings of this study highlight the need for pollen monitoring in proximity to human subjects to better understand the relationships between pollen exposures and the prevalence or severity of pollen allergy.

  14. Endotoxins: The Critical Risk Factor in Reclaimed Water via Inhalation Exposure.

    PubMed

    Xue, Jinling; Zhang, Jinshan; Xu, Bi; Xie, Jiani; Wu, Wenzhao; Lu, Yun

    2016-11-01

    The use of reclaimed water for nonpotable uses requires consideration of potential adverse health effects. Considering that inhalation can be a significant route of transmission of microorganisms and inflammatory agents, this study used a mouse model to test the possible adverse effects of reclaimed water use during car washing where aerosols are generated. Intensive innate immune responses were found in the lungs after acute exposure, and the lavage polymorphonuclear cell proportion was the most sensitive end point. Four types of evidence are presented to demonstrate that the main risk factor that initiates innate inflammation is the free endotoxin. (1) Small molecules (<10 kDa) cannot induce inflammation. (2) The endotoxin levels of 11 water samples from five different plants showed positive correlations with inflammatory responses. (3) Actual water samples showed similar activities with free endotoxins other than bacterially bound endotoxins. (4) Specific removal of endotoxins with polymyxin B affinity chromatography further confirmed the role of free endotoxins. It is noteworthy that 62.9% of the investigated tertiary-treated water had endotoxin levels higher than the allowable acute threshold (120 endotoxin units/mL) under the hypothesized car wash condition, which strongly suggests the need to carefully consider the water treatment steps required to produce safe water for various reclaimed water end uses.

  15. Detection of Endotoxin Contamination of Graphene Based Materials Using the TNF-α Expression Test and Guidelines for Endotoxin-Free Graphene Oxide Production

    PubMed Central

    Del Rio-Castillo, Antonio E.; Newman, Leon; Vázquez, Ester; Kostarelos, Kostas; Wick, Peter; Fadeel, Bengt

    2016-01-01

    Nanomaterials may be contaminated with bacterial endotoxin during production and handling, which may confound toxicological testing of these materials, not least when assessing for immunotoxicity. In the present study, we evaluated the conventional Limulus amebocyte lysate (LAL) assay for endotoxin detection in graphene based material (GBM) samples, including graphene oxide (GO) and few-layered graphene (FLG). Our results showed that some GO samples interfered with various formats of the LAL assay. To overcome this problem, we developed a TNF-α expression test (TET) using primary human monocyte-derived macrophages incubated in the presence or absence of the endotoxin inhibitor, polymyxin B sulfate, and found that this assay, performed with non-cytotoxic doses of the GBM samples, enabled unequivocal detection of endotoxin with a sensitivity that is comparable to the LAL assay. FLG also triggered TNF-α production in the presence of the LPS inhibitor, pointing to an intrinsic pro-inflammatory effect. Finally, we present guidelines for the preparation of endotoxin-free GO, validated by using the TET. PMID:27880838

  16. Intrauterine sensitization of allergen-specific IgE analyzed by a highly sensitive new allergen microarray.

    PubMed

    Kamemura, Norio; Tada, Hitomi; Shimojo, Naoki; Morita, Yoshinori; Kohno, Yoichi; Ichioka, Takao; Suzuki, Koichi; Kubota, Kenji; Hiyoshi, Mineyoshi; Kido, Hiroshi

    2012-07-01

    To design a rational allergy prevention program, it is important to determine whether allergic sensitization starts in utero under the maternal immune system. To investigate the origin of allergen-specific IgE antibodies in cord blood (CB) and maternofetal transfer of immunoglobulins. The levels of food and inhalant allergen-specific IgE, IgA, IgG, and IgG(4) antibodies in CB and maternal blood (MB) from 92 paired neonates and mothers were measured by using a novel allergen microarray of diamond-like-carbon-coated chip, with high-sensitivity detection of allergen-specific antibodies and allergen profiles. The levels of allergen-specific IgE antibodies against food and inhalant allergens and allergen profiles were identical in CB and newborn blood, but the levels and profiles, specifically against inhalant allergens, were different from those in MB. The level of allergen-specific IgA antibodies was below the detection levels in CB despite clear detection in MB. Therefore, contamination with MB in CB was excluded on the basis of extremely low levels of IgA antibodies in CB and the obvious mismatch of the allergen-specific IgE and IgA profiles between CB and MB. However, the levels of allergen-specific IgG and IgG(4) antibodies and their allergen profiles were almost identical in both MB and CB. Allergen-specific levels of IgE and IgA antibodies and their allergen profiles analyzed by the diamond-like-carbon allergen chip indicate that IgE antibodies in CB are of fetal origin. Food-allergen specific IgE antibodies were detected more often than inhalant-allergen specific IgE antibodies in CB, the reason of which remains unclarified. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  17. Endotoxin Elimination in Patients with Septic Shock: An Observation Study.

    PubMed

    Adamik, Barbara; Zielinski, Stanislaw; Smiechowicz, Jakub; Kübler, Andrzej

    2015-12-01

    To evaluate the effectiveness of endotoxin elimination with an adsorption column in patients with septic shock and endotoxemia. The elimination therapy was guided by a new bedside method of measuring endotoxin activity (EA). Intensive care unit (ICU) patients with septic shock and suspected Gram-negative infection were consecutively added to the study group within the first 24 h. Endotoxin elimination was performed using hemoperfusion with the Alteco LPS Adsorber. The primary endpoint was improvement in organ function within the first 24 h of treatment. A secondary objective was to assess the usefulness of a new method of measuring EA to help guide endotoxin elimination therapy. Out of 64 patients 18 had a high baseline EA [0.70 EA units (0.66-0.77)]. Those patients had endotoxin elimination treatment in addition to conventional medical therapy. At 24 h after endotoxin elimination, the EA had decreased to 0.56 EA units (0.43-0.77), (p = 0.005); MAP increased from 69 (62-80) to 80 mm Hg (68-88), (p = 0.002), and noradrenaline use decreased from 0.28 (0.15-0.80) to 0.1 μg/kg/min (0.00-0.70) at the same time (p = 0.04). The SOFA score had decreased from 11 (9-15) to 9 (7-14) points 24 h after endotoxin elimination (p = 0.01) with a median delta SOFA -2 points. Endotoxin elimination did not have a significant effect on the ICU length of stay or ICU mortality. Effective endotoxin elimination resulted in a significant improvement in hemodynamic parameters and of organ function. The application of the EA assay was useful for the bedside monitoring of endotoxemia in critically ill ICU patients.

  18. [Biological pollution and allergic diseases].

    PubMed

    Carrer, P; Moscato, G

    2004-01-01

    House dust mites, pets, microorganisms such as fungi and bacteria are the main causes of indoor allergens. The diseases correlated to the presence of these allergens are of increasing importance in public health as well as in occupational medicine. Indoor allergens are widespread in residential buildings as well as in public and in office buildings. Surveys conducted in Italian office buildings demonstrated detectable allergen concentrations in most of these buildings. In some cases, the concentrations were higher than the proposed risk threshold for allergenic sensitisation or for the elicitation of symptoms in allergic individuals. The health effects of exposure to indoor allergens mainly include allergic asthma and rhinoconjunctivitis caused by IgE reactions in predisposed subjects. Moreover, exposure to indoor biological agents can cause extrinsic allergic alveolitis or other effects such as the so-called "humidifier fever" due to contaminated humidifiers. Standardized methods for the measurement of indoor allergen levels are available, and may be useful for the diagnosis and treatment of individual allergic patients or for group studies in order to evaluate the relationship between allergen indoor levels and health effects or to assess indoor allergen levels in private or public buildings for preventative purposes.

  19. Endotoxin increases pulmonary vascular protein permeability in the dog

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

    Welsh, C.H.; Dauber, I.M.; Weil, J.V.

    Endotoxin increases pulmonary vascular permeability consistently in some species but fails to reliably cause injury in the dog. We wondered whether this phenomenon depended on the method of injury assessment, as others have relied on edema measurement; we quantified injury by monitoring the rate of extravascular protein accumulation. /sup 113m/In-labeled protein and /sup 99m/Tc-labeled erythrocytes were injected into anesthetized dogs and monitored by an externally placed lung probe. A protein leak index, the rate of extravascular protein accumulation, was derived from the rate of increase in lung protein counts corrected for changes in intravascular protein activity. After administration of Salmonellamore » enteriditis endotoxin (4 micrograms/kg), the protein leak index was elevated 2.5-fold (41.1 +/- 4.6 X 10(-4) min-1) compared with control (16.0 +/- 2.8 X 10(-4) min-1). In contrast, wet-to-dry weight ratios failed to increase after endotoxin (4.6 +/- 0.8 vs. control values of 4.2 +/- 0.5 g/g dry bloodless lung). However, we observed that endotoxin increased lung dry weight (per unit body weight), which may have attenuated the change in wet-to-dry weight ratios. To determine whether low microvascular pressures following endotoxin attenuated edema formation, we increased pulmonary arterial wedge pressures in five dogs by saline infusion, which caused an increase in wet-to-dry weight ratios following endotoxin but no change in the five controls. We conclude that low dose endotoxin causes pulmonary vascular protein leak in the dog while edema formation is minimal or absent.« less

  20. Nitrite/Nitrate responses to endotoxin in calves.

    PubMed

    Hüsler, B R; Blum, J W

    2001-10-01

    Plasma concentrations and urinary excretions of nitrite plus nitrate (NOx) increase in heifers after endotoxin-induced nitric oxide synthase activation. The rise can be enhanced by administration of arginine, the substrate for the production of nitric oxide, whose effects may be modified by the iron status. In 10-week-old veal calves (six Simmental x Red Holstein) arginine (0.5 g/kg body weight for 6 h) was intravenously infused. At 2 h after the start of the infusions Escherichia coli endotoxin O26:B6 (2 microg/kg body weight) was intravenously injected. This caused a rise of rectal temperature, heart rate, respiration rate, and of urinary NOx excretion, but not of plasma NOx concentrations, in contrast to the experience with older cattle to which the same amounts of arginine were infused before and during endotoxin administration. In 8-week-old veal calves (18 Simmental x Red Holstein) the question of whether oral supplementation with arginine and iron modifies NOx responses to endotoxin (2 microg/kg) was also investigated. The calves were divided between three groups (GrA-, GirA+, GrC) and before endotoxin injections GrA- was fed 0.5 g arginine/kg for 4 days, GrA+ was fed 0.5 g arginine/kg for 4 days plus 80 mg iron/kg milk for 2 weeks, whereas GrC was not supplemented with arginine or iron. Iron supplementation increased plasma iron concentrations and arginine supplementation increased plasma arginine and urea concentrations and urinary urea excretion. Ensuing administration of endotoxin enhanced plasma tumour necrosis factor-alpha concentrations, rectal temperature, heart rate, and respiration rate, but not plasma NOx concentrations in GrC and GrA- and only transiently and slightly increased plasma NOx concentrations in GrA+ but did not affect urinary NOx excretions. In conclusion, the expected stimulation of NOx responses to endotoxin by intravenous arginine infusion appears to be much weaker in young veal calves than in older cattle. The NOx responses in

  1. Determinants of endotoxin levels in carpets in New Zealand homes.

    PubMed

    Wickens, K; Douwes, J; Siebers, R; Fitzharris, P; Wouters, I; Doekes, G; Mason, K; Hearfield, M; Cunningham, M; Crane, J

    2003-06-01

    Endotoxin in house dust has been shown to be associated with asthma severity. Little is known about the influence of housing characteristics on endotoxin distribution. Using standardized methods, dust was sampled from a 1m(2) site and the whole accessible carpet area in selected Wellington, New Zealand homes (n = 77). Endotoxin was measured using a Limulus Amoebocyte Lysate assay. Relative humidity and temperature were recorded using sensors placed in carpet bases. Questionnaires were used to collect information on housing characteristics. All analyses were performed for endotoxin units (EU)/mg and EU/m2 for each site. Geometric mean endotoxin levels were 22.7 EU/mg [geometric standard deviation (GSD) = 2.4] or 30,544 EU/m2 (GSD = 3.2) from the 1m(2) site, and 28.4 EU/mg (GSD = 3.4) or 5653 EU/m2 (GSD = 6.4) from the whole room. After controlling for confounding, endotoxin was positively associated with dogs inside [geometric mean ratio (GMR): 0.9-2.0], total household occupants (GMR: 1.7-2.0, for 1 m2 sample only), vacuum cleaners <1-year old (GMR: 2.3-2.7), reusing vacuum dust collection bags (GMR: 1.4-3.1), steamcleaning or shampooing the carpet (GMR: 1.4-2.2) and high relative humidity (GMR: 1.4-1.6). Lower endotoxin was associated with floor insulation (GMR: 0.4-0.8), and north-facing living rooms (GMR: 0.4-0.8). This study has identified home characteristics that could be modified to reduce endotoxin exposure.

  2. Gender Difference in Bacteria Endotoxin-Induced Inflammatory and Anorexic Responses.

    PubMed

    Kuo, Shiu-Ming

    2016-01-01

    Inflammation-related anorexic response has been observed in systemic diseases as well as in localized infection and is an important issue in patient care. We tested the hypothesis that upon the same endotoxin exposure, males have more severe inflammatory responses and thus suffer from more negative effect on appetite. Ten-week old male and female mice were compared in their plasma levels of pro-inflammatory cytokines after a body weight-based i.p. injection of bacterial endotoxin lipopolysaccharide. Male mice consistently showed significantly higher levels of IL6 and TNFα than female mice. The difference was observed starting at 3 hours after the systemic endotoxin exposure. It was independent of the level of endotoxin dosage and of the genotype of the anti-inflammatory cytokine, IL10. Interestingly, endotoxin-injected male mice also had significantly higher plasma IL10 levels compared to the female mice. Pre-puberty young mice showed no gender differences in the plasma levels of IL6, TNFα and IL10. Their cytokine levels were mostly between that of the adult males and females. Consistent with the higher inflammatory response in male mice, the endotoxin exposure also led to significantly more appetite loss in male mice at a range of doses in two strains of mice. Saline injection in the absence of endotoxin affected neither the cytokine levels nor the appetite. Although a direct mechanistic link between inflammation parameters and appetite was not addressed here, the results support that male gender could be a risk factor for higher pro-inflammatory cytokines and anorexic response after the endotoxin exposure.

  3. [Prevalence of sensitization to allergens in school children with asthma residents from Guadalajara metropolitan area].

    PubMed

    Alcalá-Padilla, Guadalupe; Bedolla-Barajas, Martín; Kestler-Gramajo, Amanda; Valdez-López, Francisco

    2016-01-01

    Allergic sensitization is dependent on the geographical and climatic conditions in each region; therefore, identify agents most commonly sensitized children with asthma is important for planning prevention measures. To determine the prevalence of the sensitization to allergens in children with asthma. This cross-sectional and prolective study includes children from ages 6 to 14, who have asthma, attended for the first time in an allergy service. The patients were recruited consecutively between the months of January 1st 2014 to December 31st 2014. The frequency of the allergen sensitization was estimated. This study included 186 children, the median age was 7 years olds, the male group was 104/186 (55.9%) The median of the positive results was 5 and monosensitized were 47/186 (2.2%). The most common category of allergens was the indoor (90.3%), then trees (71.0%), and finally the fungi (9.7%). Individually, the house dust mites were more common in between the interior allergens, followed by the epithelial; in the tree pollen were oaks (31.7%) and ashes (28.0%), in weeds was mugwort (21.5%), in grasses was Zea mays (18.3%) and in the fungi was Cladosporium spp. (6.5%). The high prevalence of the sensitization to house dust mites and epithelial in children with asthma, stimulates to implement methods of environmental control for contributing a better control of the disease.

  4. Masking of endotoxin in surfactant samples: Effects on Limulus-based detection systems.

    PubMed

    Reich, Johannes; Lang, Pierre; Grallert, Holger; Motschmann, Hubert

    2016-09-01

    Over the last few decades Limulus Amebocyte Lysate (LAL) has been the most sensitive method for the detection of endotoxins (Lipopolysaccharides) and is well accepted in a broad field of applications. Recently, Low Endotoxin Recovery (LER) in biopharmaceutical drug products has been noticed, whereby the detection of potential endotoxin contaminations is not ensured. Notably, most of these drug products contain surfactants, which can have crucial effects on the detectability of endotoxin. In order to analyze the driving forces of LER, endotoxin detection in samples containing nonionic surfactants in various buffer systems was investigated. The results show that the process of LER is kinetically controlled and temperature-dependent. Furthermore, only the simultaneous presence of nonionic surfactants and components capable of forming metal complexes resulted in LER. In addition, capacity experiments show that even hazardous amounts of endotoxin can remain undetectable within such formulation compositions. In conclusion, the LER phenomenon is caused by endotoxin masking and not by test interference. In this process, the supramolecular structure of endotoxin is altered and exhibits only a limited susceptibility in binding to the Factor C of Limulus-based detection systems. We propose a two-step mechanism of endotoxin masking by complex forming agents and nonionic surfactants. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  5. Indoor Environmental Exposures for Children with Asthma Enrolled in the HEAL Study, Post-Katrina New Orleans

    PubMed Central

    Chulada, Patricia C.; Kennedy, Suzanne; White, LuAnn; Wildfire, Jeremy; Cohn, Richard D.; Mitchell, Herman; Thornton, Eleanor; El-Dahr, Jane; Mvula, Mosanda M.; Sterling, Yvonne; Martin, William J.; Stephens, Kevin U.; Lichtveld, Maureen

    2012-01-01

    Background: Rain and flooding from Hurricane Katrina resulted in widespread growth of mold and bacteria and production of allergens in New Orleans, Louisiana, which may have led to increased exposures and morbidity in children with asthma. Objectives: The goal of the Head-off Environmental Asthma in Louisiana (HEAL) study was to characterize post-Katrina exposures to mold and allergens in children with asthma. Methods: The homes of 182 children with asthma in New Orleans and surrounding parishes were evaluated by visual inspection, temperature and moisture measurements, and air and dust sampling. Air was collected using vacuum-pump spore traps and analyzed for > 30 mold taxa using bright field microscopy. Dust was collected from the children’s beds and bedroom floors and analyzed for mouse (Mus m 1), dust mite (Der p 1), cockroach (Bla g 1), and mold (Alternaria mix) allergens using ELISA. Results: More than half (62%) of the children were living in homes that had been damaged by rain, flooding, or both. Geometric mean indoor and outdoor airborne mold levels were 501 and 3,958 spores/m3, respectively. Alternaria antigen was detected in dust from 98% of homes, with 58% having concentrations > 10 µg/g. Mus m 1, Der p 1, and Bla g 1 were detected in 60%, 35%, and 20% of homes, respectively, at low mean concentrations. Conclusions: Except for Alternaria antigen in dust, concentrations of airborne mold (ratio of indoor to outdoor mold) and dust allergens in the homes of HEAL children were lower than measurements found in other studies, possibly because of extensive post-Katrina mold remediation and renovations, or because children moved into cleaner homes upon returning to New Orleans. PMID:22894816

  6. Antigenic Determinants of the Bilobal Cockroach Allergen Bla g 2.

    PubMed

    Woodfolk, Judith A; Glesner, Jill; Wright, Paul W; Kepley, Christopher L; Li, Mi; Himly, Martin; Muehling, Lyndsey M; Gustchina, Alla; Wlodawer, Alexander; Chapman, Martin D; Pomés, Anna

    2016-01-29

    Bla g 2 is a major indoor cockroach allergen associated with the development of asthma. Antigenic determinants on Bla g 2 were analyzed by mutagenesis based on the structure of the allergen alone and in complex with monoclonal antibodies that interfere with IgE antibody binding. The structural analysis revealed mechanisms of allergen-antibody recognition through cation-π interactions. Single and multiple Bla g 2 mutants were expressed in Pichia pastoris and purified. The triple mutant K132A/K251A/F162Y showed an ∼100-fold reduced capacity to bind IgE, while preserving the native molecular fold, as proven by x-ray crystallography. This mutant was still able to induce mast cell release. T-cell responses were assessed by analyzing Th1/Th2 cytokine production and the CD4(+) T-cell phenotype in peripheral blood mononuclear cell cultures. Although T-cell activating capacity was similar for the KKF mutant and Bla g 2 based on CD25 expression, the KKF mutant was a weaker inducer of the Th2 cytokine IL-13. Furthermore, this mutant induced IL-10 from a non-T-cell source at higher levels that those induced by Bla g 2. Our findings demonstrate that a rational design of site-directed mutagenesis was effective in producing a mutant with only 3 amino acid substitutions that maintained the same fold as wild type Bla g 2. These residues, which were involved in IgE antibody binding, endowed Bla g 2 with a T-cell modulatory capacity. The antigenic analysis of Bla g 2 will be useful for the subsequent development of recombinant allergen vaccines. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. Airborne endotoxin concentrations at a large open-lot dairy in southern idaho.

    PubMed

    Dungan, Robert S; Leytem, April B

    2009-01-01

    Endotoxins are derived from gram-negative bacteria and are a potential respiratory health risk for animals and humans. To determine the potential for endotoxin transport from a large open-lot dairy, total airborne endotoxin concentrations were determined at an upwind location (background) and five downwind locations on three separate days. The downwind locations were situated at of the edge of the lot, 200 and 1390 m downwind from the lot, and downwind from a manure composting area and wastewater holding pond. When the wind was predominantly from the west, the average endotoxin concentration at the upwind location was 24 endotoxin units (EU) m(-3), whereas at the edge of the lot on the downwind side it was 259 EU m(-3). At 200 and 1390 m downwind from the edge of the lot, the average endotoxin concentrations were 168 and 49 EU m(-3), respectively. Average airborne endotoxin concentrations downwind from the composting site (36 EU m(-3)) and wastewater holding pond (89 EU m(-3)) and 1390 m from the edge of the lot were not significantly different from the upwind location. There were no significant correlations between ambient weather data collected and endotoxin concentrations over the experimental period. The downwind data show that the airborne endotoxin concentrations decreased exponentially with distance from the lot edge. Decreasing an individual's proximity to the dairy should lower their risk of airborne endotoxin exposure and associated health effects.

  8. Alcohol, Intestinal Bacterial Growth, Intestinal Permeability to Endotoxin, and Medical Consequences

    PubMed Central

    Purohit, Vishnudutt; Bode, J. Christian; Bode, Christiane; Brenner, David A.; Choudhry, Mashkoor A.; Hamilton, Frank; Kang, Y. James; Keshavarzian, Ali; Rao, Radhakrishna; Sartor, R. Balfour; Swanson, Christine; Turner, Jerrold R.

    2008-01-01

    This report is a summary of the symposium on Alcohol, Intestinal Bacterial Growth, Intestinal Permeability to Endotoxin, and Medical Consequences, organized by National Institute on Alcohol Abuse and Alcoholism, Office of Dietary Supplements, and National Institute of Diabetes and Digestive and Kidney Diseases of National Institutes of Health in Rockville, Maryland, October 11, 2006. Alcohol exposure can promote the growth of Gram negative bacteria in the intestine which may result in accumulation of endotoxin. In addition, alcohol metabolism by Gram negative bacteria and intestinal epithelial cells can result in accumulation of acetaldehyde, which in turn can increase intestinal permeability to endotoxin by increasing tyrosine phosphorylation of tight junction and adherens junction proteins. Alcohol-induced generation of nitric oxide may also contribute to increased permeability to endotoxin by reacting with tubulin, which may cause damage to microtubule cytoskeleton and subsequent disruption of intestinal barrier function. Increased intestinal permeability can lead to increased transfer of endotoxin from the intestine to the liver and general circulation where endotoxin may trigger inflammatory changes in the liver and other organs. Alcohol may also increase intestinal permeability to peptidoglycan which can initiate inflammatory response in liver and other organs. In addition, acute alcohol exposure may potentiate the effect of burn injury on intestinal bacterial growth and permeability. Decreasing the number of Gram negative bacteria in the intestine can result in decreased production of endotoxin as well as acetaldehyde which is expected to decrease intestinal permeability to endotoxin. In addition, intestinal permeability may be preserved by administering epidermal growth factor, L-glutamine, oats supplementation, or zinc thereby preventing the transfer of endotoxin to the general circulation. Thus reducing the number of intestinal Gram negative bacteria and

  9. Predictors of Airborne Endotoxin Concentrations in Inner City Homes

    PubMed Central

    Mazique, D; Diette, GB; Breysse, PN; Matsui, EC; McCormack, MC; Curtin-Brosnan, J; Williams, D; Peng, RD; Hansel, NN

    2011-01-01

    Few studies have assessed in-home factors which contribute to airborne endotoxin concentrations. In 85 inner-city Baltimore homes, we found no significant correlation between settled dust and airborne endotoxin concentrations. Certain household activities and characteristics, including frequency of dusting, air conditioner use and type of flooring, explained 36–42% of the variability of airborne concentrations. Measurements of both airborne and settled dust endotoxin concentrations may be needed to fully characterize domestic exposure in epidemiologic investigations. PMID:21429483

  10. Effects of endotoxin on monoamine metabolism in the rat.

    NASA Technical Reports Server (NTRS)

    Pohorecky, L. A.; Wurtman, R. J.; Taam, D.; Fine, J.

    1972-01-01

    Examination of effects of administered endotoxin on catecholamine metabolism in the rat brain, sympathetic neurons, and adrenal medulla. It is found that endotoxin, administered intraperitoneally, lowers the norepinephrine content in peripheral sympathetic neurons and the brain, and the catecholamine content in the adrenal medulla. It also accelerates the disappearance of H3-norepinephrine from all these tissues. It is therefore suggested that the effects of endotoxin on body temperature may be mediated in part by central non-adrenergic neurons.

  11. Endotoxin, coliform, and dust levels in various types of rodent bedding.

    PubMed

    Whiteside, Tanya E; Thigpen, Julius E; Kissling, Grace E; Grant, Mary G; Forsythe, Diane

    2010-03-01

    Endotoxins in grain dust, household dust, and animal bedding may induce respiratory symptoms in rodents and humans. We assayed the endotoxin, coliform, and dust levels in 20 types of rodent bedding. Endotoxin concentrations were measured by using a commercial test kit, coliform counts were determined by using conventional microbiologic procedures, and dust content was evaluated by using a rotating-tapping shaker. Paper bedding types contained significantly less endotoxin than did other bedding types; the highest levels of endotoxin were detected in hardwood and corncob beddings. The range of endotoxin content for each bedding type was: corncob bedding, 1913 to 4504 endotoxin units per gram (EU/g); hardwood bedding, 3121 to 5401 EU/g; corncob-paper mixed bedding, 1586 to 2416 EU/g; and paper bedding, less than 5 to 105 EU/g. Coliform counts varied from less than 10 to 7591 cfu/g in corncob beddings, 90 to 4010 cfu/g in corncob-paper mixed beddings, less than 10 to 137 cfu/g in hardwood beddings, and less than 10 cfu/g in paper beddings. Average dust content was less than 0.15% in all commercial bedding types. We conclude that paper bedding is the optimal bedding type for conducting LPS inhalation studies and that rodent bedding containing high levels of endotoxin may alter the results of respiratory and immunologic studies in rodents.

  12. Endotoxin, Coliform, and Dust Levels in Various Types of Rodent Bedding

    PubMed Central

    Whiteside, Tanya E; Thigpen, Julius E; Kissling, Grace E; Grant, Mary G; Forsythe, Diane B

    2010-01-01

    Endotoxins in grain dust, household dust, and animal bedding may induce respiratory symptoms in rodents and humans. We assayed the endotoxin, coliform, and dust levels in 20 types of rodent bedding. Endotoxin concentrations were measured by using a commercial test kit, coliform counts were determined by using conventional microbiologic procedures, and dust content was evaluated by using a rotating–tapping shaker. Paper bedding types contained significantly less endotoxin than did other bedding types; the highest levels of endotoxin were detected in hardwood and corncob beddings. The range of endotoxin content for each bedding type was: corncob bedding, 1913 to 4504 endotoxin units per gram (EU/g); hardwood bedding, 3121 to 5401 EU/g; corncob–paper mixed bedding, 1586 to 2416 EU/g; and paper bedding, less than 5 to 105 EU/g. Coliform counts varied from less than 10 to 7591 cfu/g in corncob beddings, 90 to 4010 cfu/g in corncob–paper mixed beddings, less than 10 to 137 cfu/g in hardwood beddings, and less than 10 cfu/g in paper beddings. Average dust content was less than 0.15% in all commercial bedding types. We conclude that paper bedding is the optimal bedding type for conducting LPS inhalation studies and that rodent bedding containing high levels of endotoxin may alter the results of respiratory and immunologic studies in rodents. PMID:20353693

  13. Endotoxin Neutralization as a Biomonitor for Inflammatory Bowel Disease

    PubMed Central

    Champion, Keith; Chiu, Laura; Ferbas, John; Pepe, Michael

    2013-01-01

    Gram-negative bacterial endotoxin is a potent immunostimulant implicated in the development and/or progression of a variety of diseases. The mammalian immune system has both innate and adaptive immune responses to neutralize endotoxin. In this study, a system was developed to monitor bacterial exposure by measuring the extent and nature of endotoxin neutralization in plasma. In control patients, females had higher levels of endotoxin neutralization than males, mirroring clinical outcomes from bacterial infection and sepsis. In addition to the total amount of neutralization, we used inactivation techniques to elucidate the nature of this activity and develop a system to compare early and late immune responses. Using this method to monitor patients with inflammatory bowel disease, we found a more robust total response that relies more on long-term, adaptive components of the immune system and less on early, innate components. Our results indicate that endotoxin neutralization is a valuable method to discern inflammatory bowel disease patients from a control population. Additionally, the nature of neutralization may be valuable in monitoring disease severity and/or the role of medication. PMID:23826338

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

    PubMed

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

    2018-01-02

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

  15. In silico designed nanoMIP based optical sensor for endotoxins monitoring.

    PubMed

    Abdin, M J; Altintas, Z; Tothill, I E

    2015-05-15

    Molecular modelling was used to select specific monomers suitable for the design of molecularly imprinted polymers (MIPs) with high affinity towards endotoxins. MIPs were synthesised using solid-phase photopolymerisation with endotoxins from Escherichia coli 0111:B4 as the template. This technique also allowed the endotoxin template to be reused successfully. Particle size of ~190-220 nm was achieved with low polydispersity index, which confirms the quality of the produced MIPs. For the development of the optical sensor, SPR-2 biosensor system was used by functionalising the gold sensor chip with the MIP nanoparticles using EDC/NHS coupling procedure. The affinity based-endotoxin assay can detect endotoxins in the concentration range of 15.6-500 ng mL(-1). MIP surfaces were regenerated showing stability of the method for subsequent analysis and dissociation constants were calculated as 3.24-5.24×10(-8) M. The developed SPR sensor with the novel endotoxins nanoMIP showed the potential of the technology for endotoxins capture, detection and risk management and also the importance of computational modelling to design the artificial affinity ligands. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Endotoxin depletion of recombinant protein preparations through their preferential binding to histidine tags.

    PubMed

    Mack, Laura; Brill, Boris; Delis, Natalia; Groner, Bernd

    2014-12-01

    The presence of endotoxins in preparations of recombinantly produced therapeutic proteins poses serious problems for patients. Endotoxins can cause fever, respiratory distress syndromes, intravascular coagulation, or endotoxic shock. A number of methods have been devised to remove endotoxins from protein preparations using separation procedures based on molecular mass or charge properties. Most of the methods are limited in their endotoxin removal capacities and lack general applicability. We are describing a biotechnological approach for endotoxin removal. This strategy exploits the observation that endotoxins form micelles that expose negative charges on their surface, leading to preferential binding of endotoxins to cationic surfaces, allowing the separation from their resident protein. Endotoxins exhibit high affinity to stretches of histidines, which are widely used tools to facilitate the purification of recombinant proteins. They bind to nickel ions and are the basis for protein purification from cellular extracts by immobilized metal affinity chromatography. We show that the thrombin-mediated cleavage of two histidine tags from the purified recombinant protein and the adsorption of these histidine tags and their associated endotoxins to a nickel affinity column result in an appreciable depletion of the endotoxins in the purified protein fraction. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Distinguishing allergens from non-allergenic homologues using Physical–Chemical Property (PCP) motifs

    USDA-ARS?s Scientific Manuscript database

    Motivation: Quantitative guidelines to distinguish allergenic proteins from related, but non-allergenic ones are urgently needed for regulatory agencies, biotech companies and physicians. Cataloguing the SDAP database has indicated that allergenic proteins populate a relatively small number of prote...

  18. Effect of endotoxin and radio-detoxified endotoxin on the serum T4 level of rats and response of their thyroid gland to exogenous TSH

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

    Bertok, L.; Nagy, S.U.

    Experiments were performed to demonstrate that, while the shock-inducing dose of parent (toxic) endotoxin significantly decreases the serum T4 level of rats and inhibits the T4 response given to exogenous thyroid stimulating hormone (TSH), the radio-detoxified (/sup 60/Co-gamma, 150 kGy) endotoxin preparation does not inhibit the response to exogenous TSH. It also decreases serum T4 level to a lesser extent than untreated endotoxin.

  19. Endotoxin Contamination in Nanomaterials Leads to the Misinterpretation of Immunosafety Results

    PubMed Central

    Li, Yang; Fujita, Mayumi; Boraschi, Diana

    2017-01-01

    Given the presence of engineered nanomaterials in consumers’ products and their application in nanomedicine, nanosafety assessment is becoming increasingly important. In particular, immunosafety aspects are being actively investigated. In nanomaterial immunosafety testing strategies, it is important to consider that nanomaterials and nanoparticles are very easy to become contaminated with endotoxin, which is a widespread contaminant coming from the Gram-negative bacterial cell membrane. Because of the potent inflammatory activity of endotoxin, contaminated nanomaterials can show inflammatory/toxic effects due to endotoxin, which may mask or misidentify the real biological effects (or lack thereof) of nanomaterials. Therefore, before running immunosafety assays, either in vitro or in vivo, the presence of endotoxin in nanomaterials must be evaluated. This calls for using appropriate assays with proper controls, because many nanomaterials interfere at various levels with the commercially available endotoxin detection methods. This also underlines the need to develop robust and bespoke strategies for endotoxin evaluation in nanomaterials. PMID:28533772

  20. No increase in endotoxin release during antibiotic killing of meningococci.

    PubMed

    Prins, J M; Speelman, P; Kuijper, E J; Dankert, J; van Deventer, S J

    1997-01-01

    Endotoxin is liberated following antibiotic killing of Gram-negative rods, and antibiotics may differ in this respect. Although the amount of filterable endotoxin has also been reported to increase following antibiotic killing of meningococci, it is unknown how this influences the host response. We investigated the influence of three antibiotics on levels of free endotoxin in culture medium and cytokine production in whole blood ex vivo during killing of four strains of meningococci. Bacterial killing was significantly more efficient with penicillin or ceftriaxone than with chloramphenicol, and free endotoxin levels were lower after exposure to antibiotics as compared with no treatment (ANOVA, P < 0.001). Endotoxin levels were lowest after exposure to chloramphenicol. In three of the four strains exposure to antibiotics resulted in considerably lower cytokine levels (ANOVA, P < 0.001), and TNF-alpha levels were significantly lower after exposure to penicillin or ceftriaxone than after chloramphenicol treatment. Only in the strain that induced the lowest levels of TNF-alpha were cytokine levels comparable for untreated and treated samples. We conclude that fear of excessive endotoxin release or cytokine production caused by effective antibiotics is not justified in the treatment of meningococcal infections.

  1. Imaging Phenotype of Occupational Endotoxin-Related Lung Function Decline.

    PubMed

    Lai, Peggy S; Hang, Jing-Qing; Zhang, Feng-Ying; Sun, J; Zheng, Bu-Yong; Su, Li; Washko, George R; Christiani, David C

    2016-09-01

    Although occupational exposures contribute to a significant proportion of obstructive lung disease, the phenotype of obstructive lung disease associated with work-related organic dust exposure independent of smoking remains poorly defined. We identified the relative contributions of smoking and occupational endotoxin exposure to parenchymal and airway remodeling as defined by quantitative computed tomography (CT). The Shanghai Textile Worker Study is a longitudinal study of endotoxin-exposed cotton workers and endotoxin-unexposed silk workers that was initiated in 1981. Spirometry, occupational endotoxin exposure, and smoking habits were assessed at 5-year intervals. High-resolution computed tomography (CT) was performed in 464 retired workers in 2011, along with quantitative lung densitometric and airway analysis. Significant differences in all CT measures were noted across exposure groups. Occupational endotoxin exposure was associated with a decrease (-1.3%) in percent emphysema (LAAI-950), a 3.3-Hounsfield unit increase in 15th percentile density, an 18.1-g increase in lung mass, and a 2.3% increase in wall area percent. Current but not former smoking was associated with a similar CT phenotype. Changes in LAAI-950 were highly correlated with 15th percentile density (correlation -1.0). Lung mass was the only measure associated with forced expiratory volume in 1 sec (FEV1) decline, with each 10-g increase in lung mass associated with an additional loss (-6.1 mL) of FEV1 (p = 0.001) between 1981 and 2011. There are many similarities between the effects of occupational endotoxin exposure and those of tobacco smoke exposure on lung parenchyma and airway remodeling. The effects of occupational endotoxin exposure appear to persist even after the cessation of exposure. LAAI-950 may not be a reliable indicator of emphysema in subjects without spirometric impairment. Lung mass is a CT-based biomarker of accelerated lung function decline. Lai PS, Hang J, Zhang F, Sun J

  2. A new method for concentration analysis of bacterial endotoxins in perfluorocarbon

    NASA Astrophysics Data System (ADS)

    Chen, Dan-Dan; Feng, Xiao-Ming; Wang, Chun-Ren; Huang, Qing-Quan; Yang, Zhao-Peng; Meng, Qing-Yuan

    2014-12-01

    This communication demonstrates the feasibility of the gel-clot method for the analysis of bacterial endotoxins in water extracts of perfluorocarbon which is a water insoluble liquid medical device. Perfluorocarbon (10 mL) was shaken with 10mL water for 15 min at 2000 r/min and the endotoxin present was extracted to the aqueous phase without interference inhibition/enhancement of the product and the recovery of endotoxin added to perfluorocarbon was determined. A validation study confirmed that endotoxins presented in perfluorocarbon pass over into the aqueous phase at concentrations of 20, 10 and 5 EU/mL with recoveries from 86.8% to 96.8%. Therefore, the gel-clot test is suitable for detecting bacterial endotoxins in perfluorocarbon which is a water insoluble medical device.

  3. Food processing and allergenicity.

    PubMed

    Verhoeckx, Kitty C M; Vissers, Yvonne M; Baumert, Joseph L; Faludi, Roland; Feys, Marcel; Flanagan, Simon; Herouet-Guicheney, Corinne; Holzhauser, Thomas; Shimojo, Ryo; van der Bolt, Nieke; Wichers, Harry; Kimber, Ian

    2015-06-01

    Food processing can have many beneficial effects. However, processing may also alter the allergenic properties of food proteins. A wide variety of processing methods is available and their use depends largely on the food to be processed. In this review the impact of processing (heat and non-heat treatment) on the allergenic potential of proteins, and on the antigenic (IgG-binding) and allergenic (IgE-binding) properties of proteins has been considered. A variety of allergenic foods (peanuts, tree nuts, cows' milk, hens' eggs, soy, wheat and mustard) have been reviewed. The overall conclusion drawn is that processing does not completely abolish the allergenic potential of allergens. Currently, only fermentation and hydrolysis may have potential to reduce allergenicity to such an extent that symptoms will not be elicited, while other methods might be promising but need more data. Literature on the effect of processing on allergenic potential and the ability to induce sensitisation is scarce. This is an important issue since processing may impact on the ability of proteins to cause the acquisition of allergic sensitisation, and the subject should be a focus of future research. Also, there remains a need to develop robust and integrated methods for the risk assessment of food allergenicity. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Temporal variation in airborne microbial populations and microbially-derived allergens in a tropical urban landscape

    NASA Astrophysics Data System (ADS)

    Woo, Anthony C.; Brar, Manreetpal S.; Chan, Yuki; Lau, Maggie C. Y.; Leung, Frederick C. C.; Scott, James A.; Vrijmoed, Lilian L. P.; Zawar-Reza, Peyman; Pointing, Stephen B.

    2013-08-01

    The microbial component of outdoor aerosols was assessed along a gradient of urban development from inner-city to rural in the seasonal-tropical metropolis of Hong Kong. Sampling over a continuous one-year period was conducted, with molecular analyses to characterize bacterial and eukaryal microbial populations, immuno-assays to detect microbially-derived allergens and extensive environmental and meteorological observations. The data revealed bio-aerosol populations were not significantly impacted by the level of urban development as measured by anthropogenic pollutants and human population levels, but instead exhibited a strong seasonal trend related to general climatic variables. We applied back-trajectory analysis to establish sources of air masses and this allowed further explanation of urban bio-aerosols largely in terms of summer-marine and winter-continental origins. We also evaluated bio-aerosols for the potential to detect human health threats. Many samples supported bacterial and fungal phylotypes indicative of known pathogenic taxa, together with common indicators of human presence. The occurrence of allergenic endotoxins and beta-glucans generally tracked trends in microbial populations, with levels known to induce symptoms detected during summer months when microbial loading was higher. This strengthens calls for bio-aerosols to be considered in future risk assessments and surveillance of air quality, along with existing chemical and particulate indices.

  5. Relationships among Indoor, Outdoor, and Personal Airborne Japanese Cedar Pollen Counts

    PubMed Central

    Yamamoto, Naomichi; Matsuki, Yuuki; Yokoyama, Hiromichi; Matsuki, Hideaki

    2015-01-01

    Japanese cedar pollinosis (JCP) is an important illness caused by the inhalation of airborne allergenic cedar pollens, which are dispersed in the early spring throughout the Japanese islands. However, associations between pollen exposures and the prevalence or severity of allergic symptoms are largely unknown, due to a lack of understanding regarding personal pollen exposures in relation to indoor and outdoor concentrations. This study aims to examine the relationships among indoor, outdoor, and personal airborne Japanese cedar pollen counts. We conducted a 4-year monitoring campaign to quantify indoor, outdoor, and personal airborne cedar pollen counts, where the personal passive settling sampler that has been previously validated against a volumetric sampler was used to count airborne pollen grains. A total of 256 sets of indoor, outdoor, and personal samples (768 samples) were collected from 9 subjects. Medians of the seasonally-integrated indoor-to-outdoor, personal-to-outdoor, and personal-to-indoor ratios of airborne pollen counts measured for 9 subjects were 0.08, 0.10, and 1.19, respectively. A greater correlation was observed between the personal and indoor counts (r = 0.89) than between the personal and outdoor counts (r = 0.71), suggesting a potential inaccuracy in the use of outdoor counts as a basis for estimating personal exposures. The personal pollen counts differed substantially among the human subjects (49% geometric coefficient of variation), in part due to the variability in the indoor counts that have been found as major determinants of the personal pollen counts. The findings of this study highlight the need for pollen monitoring in proximity to human subjects to better understand the relationships between pollen exposures and the prevalence or severity of pollen allergy. PMID:26110813

  6. The molecular adsorption-type endotoxin detection system using immobilized ɛ-polylysine

    NASA Astrophysics Data System (ADS)

    Ooe, Katsutoshi; Tsuji, Akihito; Nishishita, Naoki; Hirano, Yoshiaki

    2007-12-01

    Hemodialysis for chronic renal failure is the most popular treatment method with artificial organs. However, hemodialysis patients must continue the treatment throughout their life, the results of long term extracorporeal dialysis, those patients develop the various complications and diseases, for example, dialysis amyloidosis etc. Dialysis amyloidosis is one of the refractory complications, and endotoxin is thought to be the most likely cause of it, recently. Endotoxin is one of the major cell wall components of gram-negative bacteria, and it has various biological activities. In addition, it is known that a mount of endotoxin exists in living environment, and medicine is often contaminated with endotoxin. When contaminated dialyzing fluids are used to hemodialysis, above-mentioned dialysis amyloidosis is developed. Therefore, it is important that the detection and removal of endotoxin from dialyzing fluids. Until now, the measurement methods using Limulus Amebosyte Lysate (LAL) reagent were carried out as the tests for the presence of endtoxin. However, these methods include several different varieties of measurement techniques. The following are examples of them, gelatinization method, turbidimetric assay method, colorimetric assay method and fluoroscopic method. However, these techniques needed 30-60 minutes for the measurement. From these facts, they are not able to use as a "real-time endotoxin detector". The detection of endotoxin has needed to carry out immediately, for that reason, a new detection method is desired. In this research, we focused attention to adsorption reaction between ɛ-polylysine and endotoxin. ɛ-polylysine has the structure of straight chain molecule composed by 25-30 residues made by lysine, and it is used as an antimicrobial agent, moreover, cellulose beads with immobilized ɛ-polylysine is used as the barrier filter for endotoxin removal. The endotoxin is adsorbed to immobilized ɛ-polylysine, as the result of this reaction, the

  7. Marine aerosol as a possible source for endotoxins in coastal areas.

    PubMed

    Lang-Yona, Naama; Lehahn, Yoav; Herut, Barak; Burshtein, Noa; Rudich, Yinon

    2014-11-15

    Marine aerosols, that are very common in the highly populated coastal cities and communities, may contain biological constituents. Some of this biological fraction of marine aerosols, such as cyanobacteria and plankton debris, may influence human health by inflammation and allergic reactions when inhaled. In this study we identify and compare sources for endotoxins sampled on filters in an on-shore and more-inland site. Filter analysis included endotoxin content, total bacteria, gram-negative bacteria and cyanobacteria genome concentrations as well as ion content in order to identify possible sources for the endotoxins. Satellite images of chlorophyll-a levels and back trajectory analysis were used to further study the cyanobacteria blooms in the sea, close to the trajectory of the sampled air. The highest endotoxin concentrations found in the shoreline site were during winter (3.23±0.17 EU/m(3)), together with the highest cyanobacteria genome (1065.5 genome/m(3)). The elevated endotoxin concentrations were significantly correlated with cyanobacterial levels scaled to the presence of marine aerosol (r=0.90), as well as to chlorophyll-a (r=0.96). Filters sampled further inland showed lower and non-significant correlation between endotoxin and cyanobacteria (r=0.70, P value=0.19), suggesting decrease in marine-originated endotoxin, with possible contributions from other sources of gram-negative non-cyanobacteria. We conclude that marine cyanobacteria may be a dominant contributor to elevated endotoxin levels in coastal areas. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Allergen avoidance.

    PubMed

    Woodcock, A; Custovic, A

    2000-12-09

    Allergen exposure is a risk factor for sensitisation, prevalence and severity of allergic disease. Effective allergen avoidance strategies have been devised. The cost-benefit in public health terms should be established by prospective controlled studies that are under way around the world.

  9. Food allergens in mattress dust in Norwegian homes - a potentially important source of allergen exposure.

    PubMed

    Bertelsen, R J; Faeste, C K; Granum, B; Egaas, E; London, S J; Carlsen, K-H; Lødrup Carlsen, K C; Løvik, M

    2014-01-01

    Sensitization to food allergens and food allergic reactions are mostly caused by ingesting the allergen, but can also occur from exposure via the respiratory tract or the skin. Little is known about exposure to food allergens in the home environment. The objective of this study was firstly to describe the frequency of detection of allergens from fish, egg, milk, and peanut in mattress dust collected from homes of 13-year-old adolescents and secondly to identify home characteristics associated with the presence of food allergen contamination in dust. Food allergens were measured by dot blot analysis in mattress dust from 143 homes in Oslo, Norway. We analysed associations between home characteristics (collected by parental questionnaires and study technicians) and food allergens by multivariate regression models. Fish allergen was detected in 46%, peanut in 41%, milk in 39%, and egg allergen in 22% of the mattress dust samples; only three samples contained none of these allergens. All four food allergens were more frequently detected in mattresses in small dwellings (< 100 m(2)) than larger dwellings (≥ 130 m(2)); 63-71% of the small dwellings (n = 24) had milk, peanut, and fish allergens in the samples compared with 33-44% of the larger dwellings (n = 95). Milk, peanut, and egg allergens were more frequently detected in homes with bedroom and kitchen on the same floor as compared with different floors, with odds ratios of 2.5 (95% confidence interval (CI): 1.1, 5.6) for milk, 2.4 (95% CI: 1.0, 6.1) for peanut, and 3.1 (95% CI: 1.3, 7.5) for egg allergens. Food allergens occurred frequently in beds in Norwegian homes, with dwelling size and proximity of kitchen and bedroom as the most important determinants. Due to the amount of time children spent in the bedroom, mattress dust may be an important source of exposure to food allergens. © 2013 John Wiley & Sons Ltd.

  10. Food Allergens in Mattress Dust in Norwegian Homes - A Potentially Important Source of Allergen Exposure

    PubMed Central

    Bertelsen, Randi J.; Fæste, Christiane K.; Granum, Berit; Egaas, Eliann; London, Stephanie J.; Carlsen, Kai-Håkon; Carlsen, Karin C. Lødrup; Løvik, Martinus

    2014-01-01

    Background Sensitization to food allergens and food allergic reactions are mostly caused by ingesting the allergen, but can also occur from exposure via the respiratory tract or the skin. Little is known about exposure to food allergens in the home environment. Objective To describe the frequency of detection of allergens from fish, egg, milk, and peanut in mattress dust collected from homes of 13 year old adolescents, and secondly to identify home characteristics associated with the presence of food allergen contamination in dust. Methods Food allergens were measured by dot blot analysis in mattress dust from 143 homes in Oslo, Norway. We analyzed associations between home characteristics (collected by parental questionnaires and study technicians) and food allergens by multivariate regression models. Results Fish allergen was detected in 46%, peanut in 41%, milk in 39%, and egg allergen in 22% of the mattress dust samples; only three samples contained none of these allergens. All four food allergens were more frequently detected in mattresses in small dwellings (<100m2) than larger dwellings (≥130 m2); 63-71% of the small dwellings (n=24) had milk, peanut, and fish allergens in the samples compared to 33-44% of the larger dwellings (n=95). Milk, peanut, and egg allergens were more frequently detected in homes with bedroom and kitchen on the same floor as compared with different floors; with odds ratios of 2.5 (95% confidence interval (CI): 1.1, 5.6) for milk, 2.4 (95% CI: 1.0, 6.1) for peanut, and 3.1 (95% CI: 1.3, 7.5) for egg allergens. Conclusions and clinical relevance Food allergens occurred frequently in beds in Norwegian homes, with dwelling size and proximity of kitchen and bedroom as the most important determinants. Due to the amount of time children spend in the bedroom, mattress dust may be an important source of exposure to food allergens. PMID:24304208

  11. Effects of endotoxin on mammary secretion of lactating cows. [Escherichia coli

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

    Lengemann, F.W.; Pitzrick, M.

    The objectives were to describe the magnitude and time course of changes in milk pH, Na, K, lactose, and somatic cells and to determine if paracellular pathways were altered after infusion of Escherichia coli endotoxin (serotype 0128:AB12) to produce inflammation in one-half of the udder of the goat. Intramammary infusion of endotoxin increased pH, number of somatic cells, and Na and decreased K and lactose in milk. Sodium and number of somatic cells were increased by as little as .1..mu..g of endotoxin; .25 ..mu..g produced changes in most of the other parameters; maximal effect was elicited by 1..mu..g of endotoxin.more » The gland response peaked from 5 to 7 h after infusion of endotoxin with an increase in milk cellularity as the only significant effect noted in the control gland. Infusion of (/sup 14/C)lactose into the gland and (/sup 99m/Tc)albumin into the blood demonstrated that large molecules were more able to cross into and out of udder halves after endotoxin treatment. It is suggested that ion interchange rather than bulk flow across paracellular paths is responsible for changes. In addition, endotoxin appeared to reduce lactose secretion and synthesis.« less

  12. Tree nut allergens.

    PubMed

    Geiselhart, Sabine; Hoffmann-Sommergruber, Karin; Bublin, Merima

    2018-04-18

    Tree nuts are considered as part of a healthy diet due to their high nutritional quality. However, they are also a potent source of allergenic proteins inducing IgE mediated hypersensitivity often causing serious, life-threatening reactions. The reported prevalence of tree nut allergy is up to 4.9% worldwide. The general term "tree nuts" comprises a number of nuts, seeds, and drupes, derived from trees from different botanical families. For hazelnut and walnut several allergens have been identified which are already partly applied in component resolved diagnosis, while for other tree nuts such as macadamia, coconut, and Brazil nut only individual allergens were identified and data on additional allergenic proteins are missing. This review summarizes the current knowledge on tree nut allergens and describes their physicochemical and immunological characterization and clinical relevance. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Endotoxin exposure, serum vitamin D, asthma and wheeze outcomes.

    PubMed

    Mendy, Angelico; Cohn, Richard D; Thorne, Peter S

    2016-05-01

    Endotoxin has been shown to induce neutrophilic asthma and wheeze after binding toll-like receptor 4 to produce pro-inflammatory cytokines. Animal models have demonstrated that vitamin D might inhibit lipopolysaccharide-induced cytokines. However, whether endotoxin exposure and serum vitamin D deficiency interact to affect asthma and wheeze in humans has never been investigated in an epidemiological study. Joint associations of house dust endotoxin and vitamin D with asthma and wheeze were examined using logistic regression adjusted for covariates in 5924 US participants of the National Health and Nutrition Examination Survey (NHANES). Interactions were assessed on the multiplicative as well as additive scale using the relative excess risk, the attributable portion due to additive interaction, and the synergy index. The median endotoxin concentration was 19.1 EU/mg. Prevalence of vitamin D inadequacy (20-30 ng/ml) and deficiency (<20 ng/ml) were respectively 42.9 and 33.4%. The combination of high endotoxin and low vitamin D was associated with current asthma (OR: 1.56, 95% CI: 1.09, 2.23), wheeze in the past 12 months (OR: 1.72, 95% CI: 1.10, 3.71), recurrent wheeze (OR: 1.97, 95% CI: 1.00, 4.00), asthma diagnosis or recurrent wheeze (OR: 1.88, 95% CI: 1.33, 2.66), and current asthma or recurrent wheeze (OR:1.81, 95% CI: 1.23, 2.68) when compared to low endotoxin and normal vitamin D. The interactions between the exposures were not significant on the multiplicative or additive scale for any of the outcomes. Combination of high endotoxin exposure and low vitamin D increases the odds of asthma and wheeze, but the exposures do not interact or modify each other's effect in the NHANES cohort. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Exposure to airborne microorganisms, dust and endotoxin during processing of peppermint and chamomile herbs on farms.

    PubMed

    Skórska, Czesława; Sitkowska, Jolanta; Krysińska-Traczyk, Ewa; Cholewa, Grazyna; Dutkiewicz, Jacek

    2005-01-01

    The aim of this study was to determine the levels of microorganisms, dust and endotoxin in the air during processing of peppermint (Mentha piperita) and chamomile (Matricaria recutita) by herb farmers, and to examine the species composition of airborne microflora. Air samples were collected on glass fibre filters by use of personal samplers on 13 farms owned by herb cultivating farmers, located in Lublin province (eastern Poland). The concentrations of total viable microorganisms (bacteria + fungi) in the farm air during processing of peppermint herb were large, within a range from 895.1-6,015.8 x 10(3) cfu/m(3) (median 1,055.3 x 10(3) cfu/m(3)). During processing of chamomile herb they were much lower and varied within a range from 0.88-295.6 x 10(3) cfu/m(3) (median 27.3 x 10(3) cfu/m(3)). Gram-negative bacteria distinctly prevailed during processing of peppermint leaves, forming 46.4-88.5 % of the total airborne microflora. During processing of chamomile herb, Gram-negative bacteria were dominant at 3 out of 6 sampling sites forming 54.7-75.3 % of total microflora, whereas at the remaining 3 sites the most common were fungi forming 46.2-99.9 % of the total count. The species Pantoea agglomerans (synonyms: Erwinia herbicola, Enterobacter agglomerans ), having strong allergenic and endotoxic properties, distinctly prevailed among Gram-negative isolates. Among fungi, the most common species was Alternaria alternata. The concentrations of airborne dust and endotoxin determined on the examined herb farms were large. The concentrations of airborne dust during peppermint and chamomile processing ranged from 86.7-958.9 mg/m(3), and from 1.1-499.2 mg/m(3), respectively (medians 552.3 mg/m(3) and 12.3 mg/m(3)). The concentrations of airborne endotoxin determined during peppermint and chamomile processing were within a wide range 1.53-208.33 microg/m(3) and 0.005-2604.19 microg/m(3) respectively (medians 57.3 microg/m(3) and 0.96 microg/m(3)). In conclusion, farmers

  15. A comparative study of different strategies for removal of endotoxins from bacteriophage preparations.

    PubMed

    Van Belleghem, Jonas D; Merabishvili, Maya; Vergauwen, Bjorn; Lavigne, Rob; Vaneechoutte, Mario

    2017-01-01

    Bacterial endotoxins have high immunogenicity. Phage biology studies as well as therapeutic phage applications necessitate highly purified phage particles. In this study, we compared combinations of seven different endotoxin removal strategies and validated their endotoxin removal efficacy for five different phages (i.e. four Pseudomonas aeruginosa phages and one Staphylococcus aureus phage). These purification strategies included Endotrap HD column purification and/or CsCl density centrifugation in combination with Endotrap purification, followed by organic solvent (1-octanol), detergent (Triton X-100), enzymatic inactivation of the endotoxin using alkaline phosphatase and CIM monolytic anion exchange chromatography. We show that CsCl density purification of the P. aeruginosa phages, at an initial concentration of 10 12 -10 13 pfu/ml, led to the strongest reduction of endotoxins, with an endotoxin removal efficacy of up to 99%, whereas additional purification methods did not result in a complete removal of endotoxins from the phage preparations and only yielded an additional endotoxin removal efficacy of 23 to 99%, sometimes accompanied with strong losses in phage titer. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Polymyxin B immobilized on cross-linked cellulose microspheres for endotoxin adsorption.

    PubMed

    Cao, Xiaodong; Zhu, Biyan; Zhang, Xufeng; Dong, Hua

    2016-01-20

    Cross-linked cellulose microspheres (CL-CMs) were successfully prepared by inverse crosslinking suspension method. NaOH/urea aqueous solution was used as solvent to dissolve cellulose at low temperature. The microspheres presented good spherical shape and monodispersity, which were applied to synthesize endotoxin adsorbent with polymyxin B (PMB) as ligand. The adsorbent showed good adsorption capability on endotoxin in physiologic saline solution and the maximum adsorption capacity was 3605 EU/g (1 EU=100 pg). It was worth noting that more than 70% of endotoxin could be effectively removed from the human plasma with the initial concentration of endotoxin ranged from 1 EU/mL to 5 EU/mL. The dynamic adsorption efficiency of endotoxin was 72.3% at the plasma perfusion rate of 300 mL/h with the endotoxin concentration of 4 EU/mL, while the variation of plasma protein before and after adsorption was only 8.9%. It suggests that the PMB immobilized CL-CMs have great potential application in clinical blood purification. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Endotoxin inactivation via steam-heat treatment in dilute simethicone emulsions used in biopharmaceutical processes.

    PubMed

    Britt, Keith A; Galvin, Jeffrey; Gammell, Patrick; Nti-Gyabaah, Joseph; Boras, George; Kolwyck, David; Ramirez, José G; Presente, Esther; Naugle, Gregory

    2014-01-01

    Simethicone emulsion is used to regulate foaming in cell culture operations in biopharmaceutical processes. It is also a potential source of endotoxin contamination. The inactivation of endotoxins in dilute simethicone emulsions was assessed as a function of time at different steam temperatures using a Limulus amebocyte lysate kinetic chromogenic technique. Endotoxin inactivation from steam-heat treatment was fit to a four-parameter double exponential decay model, which indicated that endotoxin inactivation was biphasic, consisting of fast and slow regimes. In the fast regime, temperature-related effects were dominant. Transitioning into the slow regime, the observed temperature dependence diminished, and concentration-related effects became increasingly significant. The change in the Gibbs free energy moving through the transition state indicated that a large energy barrier must be overcome for endotoxin inactivation to occur. The corresponding Arrhenius pre-exponential factor was >10(12) s(-1) suggesting that endotoxins in aqueous solution exist as aggregates. The disorder associated with the endotoxin inactivation reaction pathway was assessed via the change in entropy moving through the transition state. This quantity was positive indicating that endotoxin inactivation may result from hydrolysis of individual endotoxin molecules, which perturbs the conformation of endotoxin aggregates, thereby modulating the biological activity observed. Steam-heat treatment decreased endotoxin levels by 1-2 logarithm (log) reduction (LRV), which may be practically relevant depending on incoming raw material endotoxin levels. Antifoam efficiency and cell culture performance were negligibly impacted following steam-heat treatment. The results from this study show that steam-heat treatment is a viable endotoxin control strategy that can be implemented to support large-scale biopharmaceutical manufacturing. © 2014 American Institute of Chemical Engineers.

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

    PubMed Central

    Sharma, Dhruba; 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 40% from skin allergy. The dominant mites recorded from indoor dust samples were Dermatophagoides followed by Blomia, Acarus, and Cheyletus while Caloglyphus was recorded in least number. The distribution of mites on the basis of housing pattern indicates that RCC type of buildings supports maximum dust mite's population followed by Assam type (semi-RCC) buildings, and the lowest count was observed in wooden houses. Environmental factors like temperature, rainfall, and relative humidity are found to determine the indoor mite's population. Severity of allergic attack in some of the typical cases was found to be proportional to the allergen load of mites in the dust samples. Conclusions. The economic status, housing pattern, and local environmental factors determine the diversity and abundance of dust mites in indoor environment. PMID:23724231

  19. [Review on characteristics and detecting assay of bacterial endotoxin contamination in water environment].

    PubMed

    Zhang, Can; Liu, Wen-Jun; Zhang, Ming-Lu; Tian, Fang; Yang, Yi; An, Dai-Zhi

    2014-04-01

    Endotoxins, also known as lipopolysaccharide complexes, are anchored in the outer membrane cell wall of most Gram-negative bacteria and some cyanobacteria. They are continuously released to environment during cell decay. Being common pyrogens and highly immunogenic molecules, endotoxins are related to many human diseases. Due to the tolerances and thermo-stability of endotoxin molecules, they were hard to be removed by common methods. The health risk caused by the endotoxin contamination in drinking water and water environment by various exposure pathways have attracted more and more attention in recent years. In this paper, the physical and chemical properties, biological activities and detection assay of the endotoxin contamination were reviewed, and interfere factors of the main assay, the LAL/TAL (Limulus amebocyte lysate/Tachypleus amebocyte lysate) assay, for detecting endotoxin in water sample were investigated, and the development tendency of the endotoxin detection assay was analyzed.

  20. [Health effects of occupational endotoxin exposure: a review and relevance to veterinary practice].

    PubMed

    Smit, Lidwien A M; Wouters, Inge M; Heederik, Dick; Douwes, Jeroen

    2009-10-15

    Endotoxins are cell-wall components of Gram-negative bacteria that are commonly present in plants and plant products and in faecal matter. This review presents an overview of endotoxin exposure levels, associated health effects, and relevance regarding veterinary practice. Exposure to airborne endotoxin is especially high in the agricultural sector and among veterinarians, and in particular among those working with horses or farm animals. Inhalation of endotoxins may cause acute airway inflammation and respiratory symptoms that can lead to (non-allergic) asthma and chronic obstructive pulmonary disease in individuals with prolonged exposure to high levels of endotoxins. Interestingly, recent studies have shown that individuals exposed to high levels of endotoxin also have a lower risk of allergic conditions such as hay fever. Although endotoxin may protect against allergies, it is essential to reduce exposure levels in the agricultural sector in order to prevent workers from developing chronic non-allergic respiratory disorders.

  1. A non-chromatographic method for the removal of endotoxins from bacteriophages.

    PubMed

    Branston, Steven D; Wright, Jason; Keshavarz-Moore, Eli

    2015-08-01

    The Ff filamentous bacteriophages show potential as a new class of therapeutics, displaying utility in materials science as well as pharmaceutical applications. These phages are produced by the infection of E. coli, a Gram-negative bacterium which unavoidably sheds endotoxins into the extracellular space during growth. Since endotoxin molecules are highly immunoreactive, separation from the phage product is of critical importance, particularly those developed for human therapeutic use. The properties of M13, one of the Ff group, present a purification challenge chiefly because the standard scalable method for endotoxin removal from proteins-anion exchange chromatography-is not applicable due to pI similarity between the particles. This article examines the potential of polyethylene glycol (PEG)-NaCl precipitation as a scalable method for the separation of endotoxins from phage M13. Precipitation of M13 by 2% (w/v) PEG 6 000, 500 mM NaCl reduced endotoxin contamination of the phage product by 88%, but additional precipitation rounds did not maintain this proportional decrease. Dynamic light scattering was subsequently used to determine the effectiveness of a detergent to disassociate endotoxin molecules from M13. As a result, PEG-NaCl precipitation was supplemented with up to 2% (v/v) Triton X-100 to improve separation. A 5.7 log10 reduction in endotoxin concentration was achieved over three rounds of precipitation whilst retaining over 97% of the phage. This method compares favorably with the well-known ATPS (Triton X-114) technique for endotoxin removal from protein solutions. © 2015 Wiley Periodicals, Inc.

  2. Detection of major food allergens in amniotic fluid: initial allergenic encounter during pregnancy.

    PubMed

    Pastor-Vargas, Carlos; Maroto, Aroa S; Díaz-Perales, Araceli; Villalba, Mayte; Esteban, Vanesa; Ruiz-Ramos, Marta; de Alba, Marta Rodriguez; Vivanco, Fernando; Cuesta-Herranz, Javier

    2016-11-01

    Ingestion of food allergens present in maternal milk during breastfeeding has been hypothesized as a gateway to sensitization to food; however, this process could develop during pregnancy, as the maternal-fetal interface develops a Th2- and Treg-mediated environment to protect the fetus. We hypothesized that in these surroundings, unborn children are exposed to food allergens contained in the mother's diet, possibly giving rise to first sensitization. The presence of allergens in utero was studied by analyzing amniotic fluid (AF) samples in two different stages of pregnancy: at 15-20 weeks and after delivery at term. An antibody microarray was developed to test for the most common food allergens. The array detects the presence of ten allergens from milk, fruit, egg, fish, nuts, and wheat. AF from 20 pregnant women was collected: eight after delivery at term and 12 from women who underwent diagnostic amniocentesis between weeks 15 and 20 of gestation. The presence of allergens was detected in all samples. Samples from amniocentesis had a higher allergen concentration than samples after delivery at term. We demonstrated the presence of intact major food allergens in AF samples. This early contact could explain subsequent sensitization to foods never eaten before. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Association of Endotoxins and Colon Polyp: A Case-Control Study

    PubMed Central

    Lee, Kang-Kon

    2012-01-01

    Endotoxins are known to be associated with the occurrence of various chronic diseases. This study was conducted to investigate the role of endotoxins in the pathogenesis of colon polyps through a case-control study. A total of 145 subjects (74 subjects in the polyp group and 71 subjects in the control group) had undergone a colonoscopy. Age, body mass index (BMI) and endotoxin levels were found to be significantly higher in the polyp group than in the control group. The endotoxin level was still significantly higher in the polyp group than in the control group, even after age and BMI had been adjusted (polyp group 0.108 ± 0.007 EU/mL, control group 0.049 ± 0.008 EU/mL, P < 0.001). In subgroup analysis, the endotoxin level significantly increased in accordance with the number of colon polyps (one-polyp group, 0.088 ± 0.059 EU/mL; two-polyp group, 0.097 ± 0.071 EU/mL; three-or-more-polyp group, 0.149 ± 0.223 EU/mL). The endotoxin levels also significantly increased in groups with tubular adenoma with high-grade dysplasia (hyperplastic polyp group, 0.109 ± 0.121 EU/mL; tubular adenoma with low grade dysplasia group, 0.103 ± 0.059 EU/mL; tubular adenoma with high grade dysplasia group, 2.915 ± 0.072 EU/mL). In conclusion, the serum level of endotoxins is quantitatively correlated with colon polyps. PMID:22969253

  4. Exposure to Dust and Endotoxin of Employees in Cucumber and Tomato Nurseries

    PubMed Central

    Madsen, A. M.; Hansen, V. M.; Nielsen, S. H.; Olsen, T. T.

    2009-01-01

    Exposure to bioaerosols in occupational settings is associated with a range of adverse health effects. The aim of this study was to investigate the exposure levels to dust and endotoxin of people working in two cucumber nurseries and two tomato nurseries. Exposure was measured for greenhouse workers (n = 70) mainly working on harvesting cucumbers and tomatoes and clearing the plants after the harvest season. The people were exposed to between 0.2 and 15 mg inhalable dust m−3 (median = 1.6 mg m−3) and between 0.5 and 400 ng inhalable endotoxin m−3 (median = 32 ng m−3). The exposure to ‘total dust’ and endotoxin measured by stationary samplers (n = 30) in the greenhouses was low. Endotoxin was present in relatively high concentrations on cucumber leaves compared with leaves on pot plants. The Danish occupational exposure limit (OEL) for total organic dust is 3 mg m−3 and 36% and 17% of the cucumber and tomato workers, respectively, were exposed to >3.0 mg inhalable dust m−3. There is no OEL for endotoxin, but ‘no effect levels’ at ∼15 ng m−3 have been found. The majority of subjects (65%) were exposed to >15 ng m−3. Significantly higher exposure was found for employees in cucumber nurseries than for employees in tomato nurseries. Clearing tomato plants after the harvest season caused a higher exposure to endotoxin than tomato harvesting. In conclusion, people working in cucumber and tomato nurseries were often exposed to high levels of inhalable dust and endotoxin. Cucumber harvest workers were exposed to significantly more dust and endotoxin than tomato harvest workers. The dust and endotoxin aerosolized during the working processes were only transported to other areas in the greenhouses to a very low degree. Cucumber and tomato leaves were identified as endotoxin reservoirs. PMID:19033558

  5. Kinetics of Hydrothermal Inactivation of Endotoxins

    PubMed Central

    Li, Lixiong; Wilbur, Chris L.; Mintz, Kathryn L.

    2011-01-01

    A kinetic model was established for the inactivation of endotoxins in water at temperatures ranging from 210°C to 270°C and a pressure of 6.2 × 106 Pa. Data were generated using a bench scale continuous-flow reactor system to process feed water spiked with endotoxin standard (Escherichia coli O113:H10). Product water samples were collected and quantified by the Limulus amebocyte lysate assay. At 250°C, 5-log endotoxin inactivation was achieved in about 1 s of exposure, followed by a lower inactivation rate. This non-log-linear pattern is similar to reported trends in microbial survival curves. Predictions and parameters of several non-log-linear models are presented. In the fast-reaction zone (3- to 5-log reduction), the Arrhenius rate constant fits well at temperatures ranging from 120°C to 250°C on the basis of data from this work and the literature. Both biphasic and modified Weibull models are comparable to account for both the high and low rates of inactivation in terms of prediction accuracy and the number of parameters used. A unified representation of thermal resistance curves for a 3-log reduction and a 3 D value associated with endotoxin inactivation and microbial survival, respectively, is presented. PMID:21193667

  6. Dexamethasone inhibits endotoxin-induced coagulopathy in human lungs.

    PubMed

    Bartko, J; Schoergenhofer, C; Schwameis, M; Buchtele, N; Wojta, J; Schabbauer, G; Stiebellehner, L; Jilma, B

    2016-12-01

    Essentials Glucocorticoids are associated with an increased risk of thrombosis. Healthy volunteers received dexamethasone or placebo in an endotoxin lung instillation model. Dexamethasone suppressed thrombin generation in bronchoalveolar lavage. Glucocorticoids inhibit endotoxin induced pulmonary coagulopathy. Background Activation of local and systemic coagulation is a common finding in patients with pneumonia. There is evidence that glucocorticoids have procoagulant activity in the circulation, particularly in the context of inflammation. The effects of glucocorticoids on local pulmonary coagulation have not yet been investigated. Objective To use a human model of lung inflammation based on the local instillation of endotoxin in order to investigate whether glucocorticoids alter pulmonary coagulation. Methods Twenty-four healthy volunteers were randomized to receive either dexamethasone or placebo in a double-blind trial. Endotoxin was instilled via bronchoscope into right or left lung segments, followed by saline into the contralateral site. Six hours later, a bilateral bronchoalveolar lavage (BAL) was performed and coagulation parameters were measured. Results Endotoxin induced activation of coagulation in the bronchoalveolar compartment: the level of prothrombin fragment 1 + 2 (F 1 + 2 ) was increased three-fold (248 pmol L -1 , 95% confidence interval [CI] 43-454 versus 743 pmol L -1 , 95% CI 437-1050) and the level of thrombin-antithrombin complex (TATc) was increased by ~ 50% (31 μg L -1 , 95% CI 18-45 versus 49 μg L -1 , 95% CI 36-61) as compared with saline-challenged segments. Dexamethasone reduced F 1 + 2 (284 pmol L -1 , 95% CI 34-534) and TATc (9 μg L -1 , 95% CI 0.7-17) levels almost to those measured in BAL fluid from the saline-instilled segments in the placebo group. Dexamethasone even profoundly reduced F 1 + 2 levels (80%) in saline-instilled lung segments (50 pmol L -1 , 95% CI 12-87). In contrast, dexamethasone had no effect on systemic F 1

  7. Determination of allergen specificity by heavy chains in grass pollen allergen-specific IgE antibodies.

    PubMed

    Gadermaier, Elisabeth; Flicker, Sabine; Lupinek, Christian; Steinberger, Peter; Valenta, Rudolf

    2013-04-01

    Affinity and clonality of allergen-specific IgE antibodies are important determinants for the magnitude of IgE-mediated allergic inflammation. We sought to analyze the contribution of heavy and light chains of human allergen-specific IgE antibodies for allergen specificity and to test whether promiscuous pairing of heavy and light chains with different allergen specificity allows binding and might affect affinity. Ten IgE Fabs specific for 3 non-cross-reactive major timothy grass pollen allergens (Phl p 1, Phl p 2, and Phl p 5) obtained by means of combinatorial cloning from patients with grass pollen allergy were used to construct stable recombinant single chain variable fragments (ScFvs) representing the original Fabs and shuffled ScFvs in which heavy chains were recombined with light chains from IgE Fabs with specificity for other allergens by using the pCANTAB 5 E expression system. Possible ancestor genes for the heavy chain and light chain variable region-encoding genes were determined by using sequence comparison with the ImMunoGeneTics database, and their chromosomal locations were determined. Recombinant ScFvs were tested for allergen specificity and epitope recognition by means of direct and sandwich ELISA, and affinity by using surface plasmon resonance experiments. The shuffling experiments demonstrate that promiscuous pairing of heavy and light chains is possible and maintains allergen specificity, which is mainly determined by the heavy chains. ScFvs consisting of different heavy and light chains exhibited different affinities and even epitope specificity for the corresponding allergen. Our results indicate that allergen specificity of allergen-specific IgE is mainly determined by the heavy chains. Different heavy and light chain pairings in allergen-specific IgE antibodies affect affinity and epitope specificity and thus might influence clinical reactivity to allergens. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by

  8. Collaborative study for the establishment of the WHO 3(rd) International Standard for Endotoxin, the Ph. Eur. endotoxin biological reference preparation batch 5 and the USP Reference Standard for Endotoxin Lot H0K354.

    PubMed

    Findlay, L; Desai, T; Heath, A; Poole, S; Crivellone, M; Hauck, W; Ambrose, M; Morris, T; Daas, A; Rautmann, G; Buchheit, K H; Spieser, J M; Terao, E

    2015-01-01

    An international collaborative study was organised jointly by the World Health Organization (WHO)/National Institute for Biological Standards and Control (NIBSC), the United States Pharmacopeia (USP) and the European Directorate for the Quality of Medicines & HealthCare (EDQM/Council of Europe) for the establishment of harmonised replacement endotoxin standards for these 3 organisations. Thirty-five laboratories worldwide, including Official Medicines Control Laboratories (OMCLs) and manufacturers enrolled in the study. Three candidate preparations (10/178, 10/190 and 10/196) were produced with the same material and same formulation as the current reference standards with the objective of generating a new (3(rd)) International Standard (IS) with the same potency (10 000 IU/vial) as the current (2(nd)) IS, as well as new European Pharmacopoeia (Ph. Eur.). and USP standards. The suitability of the candidate preparations to act as the reference standard in assays for endotoxin performed according to compendial methods was evaluated. Their potency was calibrated against the WHO 2(nd) IS for Endotoxin (94/580). Gelation and photometric methods produced similar results for each of the candidate preparations. The overall potency estimates for the 3 batches were comparable. Given the intrinsic assay precision, the observed differences between the batches may be considered unimportant for the intended use of these materials. Overall, these results were in line with those generated for the establishment of the current preparations of reference standards. Accelerated degradation testing of vials stored at elevated temperatures supported the long-term stability of the 3 candidate preparations. It was agreed between the 3 organisations that batch 10/178 be shared between WHO and EDQM and that batches 10/190 and 10/196 be allocated to USP, with a common assigned value of 10 000 IU/vial. This value maintains the continuity of the global harmonisation of reference materials and

  9. The Effect of Intra-Dialytic Exercise on Inflammation and Blood Endotoxin Levels.

    PubMed

    Wong, Jonathan; Davis, Philip; Patidar, Ashish; Zhang, Yonglong; Vilar, Enric; Finkelman, Malcolm; Farrington, Ken

    2017-01-01

    In healthy individuals, an acute inflammatory response occurs after intense exercise due to gut ischaemia and intestinal bacterial endotoxin translocation into the bloodstream. This process maybe exacerbated in patients who exercise during dialysis due to large volume shifts experienced by many during haemodialysis (HD). The acute effect of intra-dialytic exercise on blood endotoxins and inflammation is not known. The effect of intra-dialytic exercise on blood endotoxin and inflammation was investigated in 10 patients and compared with resting haemodialysis. Blood was measured for endotoxin and inflammatory biomarkers before and after dialysis. With the exception of one sample, all samples tested negative for endotoxin. Intra-dialytic exercise attenuated the rise of interleukin-6, tumour necrosis factor-α and high-sensitivity C-reactive protein after the HD procedure. Intra-dialytic exercise was not associated with an observable rise in blood endotoxin, although it may ameliorate the inflammatory effects of the HD procedure. Larger studies are needed to confirm this finding. © 2017 S. Karger AG, Basel.

  10. Some metabolic effects of bacterial endotoxins in salmonid fishes

    USGS Publications Warehouse

    Wedemeyer, G.A.; Ross, A.J.; Smith, L.

    1968-01-01

    Coho salmon (Oncorhynchus kisutch) and rainbow trout (Salmo gairdneri) were highly resistant to endotoxins from both Escherichia coli and Aeromonas salmonicida (a fish pathogen) at 14 and 18 C.This resistance was investigated with liver tryptophan pyrrolase, liver glycogen depletion in vitro, and the arterial blood pressure as indicators. Liver glycogen depletion was accelerated by both endotoxins, but there was no significant cardiovascular response or effect on liver tryptophan pyrrolase activity. Since the cardiovascular effects of histamine were also limited, it was concluded that the metabolic effects of bacterial endotoxins in salmonids are qualitatively different from those of the higher vertebrates.

  11. Removal of endotoxin from deionized water using micromachined silicon nanopore membranes

    NASA Astrophysics Data System (ADS)

    Smith, Ross A.; Goldman, Ken; Fissell, William H.; Fleischman, Aaron J.; Zorman, Christian A.; Roy, Shuvo

    2011-05-01

    Endotoxins are lipopolysaccharide components of the cell membrane of Gram-negative bacteria that trigger the body's innate immune system and can cause shock and death. Water for medical therapy, including parenteral and dialysate solutions, must be free of endotoxin. This purity is challenging to achieve as many Gram-negative bacteria are endemic in the environment, and can thrive in harsh, nutrient-poor conditions. Current methods for removing endotoxin include distillation and reverse osmosis, both of which are resource intensive processes. Membranes that present an absolute barrier to macromolecular passage may be capable of delivering pure water for biomedical applications. In this work, endotoxin has been filtered from aqueous solutions using silicon nanopore membranes (SNMs) with monodisperse pore size distributions. SNMs with critical pore sizes between 26 and 49 nm were challenged with solutions of deionized water spiked with endotoxin and with Pseudomonas cepacia. The filtrate produced by the SNM from Pseudomonas-contaminated water had <1.0 endotoxin unit (EU) ml-1, which meets standards for dialysate purity. This approach suggests a technique for single-step cleanup of heavily contaminated water that may be suitable for field or clinical use.

  12. Molecular properties of food allergens.

    PubMed

    Breiteneder, Heimo; Mills, E N Clare

    2005-01-01

    Plant food allergens belong to a rather limited number of protein families and are also characterized by a number of biochemical and physicochemical properties, many of which are also shared by food allergens of animal origin. These include thermal stability and resistance to proteolysis, which are enhanced by an ability to bind ligands, such as metal ions, lipids, or steroids. Other types of lipid interaction, including membranes or other lipid structures, represent another feature that might promote the allergenic properties of certain food proteins. A structural feature clearly related to stability is intramolecular disulfide bonds alongside posttranslational modifications, such as N-glycosylation. Some plant food allergens, such as the cereal seed storage prolamins, are rheomorphic proteins with polypeptide chains that adopt an ensemble of secondary structures resembling unfolded or partially folded proteins. Other plant food allergens are characterized by the presence of repetitive structures, the ability to form oligomers, and the tendency to aggregate. A summary of our current knowledge regarding the molecular properties of food allergens is presented. Although we cannot as yet predict the allergenicity of a given food protein, understanding of the molecular properties that might predispose them to becoming allergens is an important first step and will undoubtedly contribute to the integrative allergenic risk assessment process being adopted by regulators.

  13. Endogenous allergens and compositional analysis in the allergenicity assessment of genetically modified plants.

    PubMed

    Fernandez, A; Mills, E N C; Lovik, M; Spoek, A; Germini, A; Mikalsen, A; Wal, J M

    2013-12-01

    Allergenicity assessment of genetically modified (GM) plants is one of the key pillars in the safety assessment process of these products. As part of this evaluation, one of the concerns is to assess that unintended effects (e.g. over-expression of endogenous allergens) relevant for the food safety have not occurred due to the genetic modification. Novel technologies are now available and could be used as complementary and/or alternative methods to those based on human sera for the assessment of endogenous allergenicity. In view of these developments and as a step forward in the allergenicity assessment of GM plants, it is recommended that known endogenous allergens are included in the compositional analysis as additional parameters to be measured. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. New routes of allergen immunotherapy.

    PubMed

    Aricigil, Mitat; Muluk, Nuray Bayar; Sakarya, Engin Umut; Sakalar, Emine Güven; Senturk, Mehmet; Reisacher, William R; Cingi, Cemal

    2016-11-01

    Allergen immunotherapy is the only cure for immunoglobulin E mediated type I respiratory allergies. Subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are the most common treatments. In this article, we reviewed new routes of allergen immunotherapy. Data on alternative routes to allow intralymphatic immunotherapy (ILIT), epicutaneous immunotherapy (EPIT), local nasal immunotherapy (LNIT), oral immunotherapy (OIT), and oral mucosal immunotherapy (OMIT) were gathered from the literature and were discussed. ILIT features direct injection of allergens into lymph nodes. ILIT may be clinically effective after only a few injections and induces allergen-specific immunoglobulin G, similarly to SCIT. A limitation of ILIT is that intralymphatic injections are required. EPIT features allergen administration by using patches mounted on the skin. EPIT seeks to target epidermal antigen-presenting Langerhans cells rather than mast cells or the vasculature; this should reduce both local and systemic adverse effects. LNIT involves the spraying of allergen extracts into the nasal cavity. Natural or chemically modified allergens (the latter, termed allergoids, lack immunoglobulin E reactivity) are prepared in a soluble form. OIT involves the regular administration of small amounts of a food allergen by mouth and commences with low oral doses, which are then increased as tolerance develops. OMIT seeks to deliver allergenic proteins to an expanded population of Langerhans cells in the mucosa of the oral cavity. ILIT, EPIT, LNIT, OIT, and OMIT are new routes for allergen immunotherapy. They are safe and effective.

  15. New tree nut allergens

    USDA-ARS?s Scientific Manuscript database

    The 7S vicilin and 11S legumin seed storage globulins belong to the cupin protein superfamily and are major food allergens in many of the “big eight” food allergen groups. Korean pine vicilin and pecan vicilin are thus predicted to be food allergens. Recombinant vicilins were expressed in E. coli an...

  16. Removal of endotoxin from water by microfiltration through a microporous polyethylene hollow-fiber membrane

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

    Sawada, Y.; Fujii, R.; Igami, I.

    The microporous polyethylene hollow-fiber membrane has a unique microfibrile structure throughout its depth and has been found to possess the functions of filtration and adsorption of endotoxin in water. The membrane has a maximum pore diameter of approximately 0.04 micron, a diameter which is within the range of microfiltration. Approximately 10 and 20% of the endotoxin in tap water and subterranean water, respectively, was smaller than 0.025 micron. Endotoxin in these water sources was efficiently removed by the microporous polyethylene hollow-fiber membrane. Escherichia coli O113 culture broth contained 26.4% of endotoxin smaller than 0.025 micron which was also removed. Endotoxinmore » was leaked into the filtrate only when endotoxin samples were successively passed through the membrane. These results indicate that endotoxin smaller than the pore size of the membrane was adsorbed and then leaked into the filtrate because of a reduction in binding sites. Dissociation of /sup 3/H-labeled endotoxin from the membrane was performed, resulting in the removal of endotoxin associated with the membrane by alcoholic alkali at 78% efficiency.« less

  17. Protection against endotoxin-induced foetal resorption in mice by desferrioxamine and ebselen.

    PubMed Central

    Gower, J. D.; Baldock, R. J.; O'Sullivan, A. M.; Doré, C. J.; Coid, C. R.; Green, C. J.

    1990-01-01

    Endotoxin was administered to mice on their 13th day of pregnancy at doses which caused the resorption of approximately 50% of the implanted foetuses. The iron chelator desferrioxamine was found to significantly inhibit the percentage of resorptions induced by endotoxin in a dose-dependent manner. The highest dose of desferrioxamine (5 mg) given intravenously 30 min prior to, immediately after, and 4 and 24 h after endotoxin inoculation, reduced the percentage of resorptions from 56.9 to 17.9%. Administration of the novel selenium-containing compound ebselen, which is both an antioxidant and an inhibitor of leukotriene synthesis, was also found to significantly protect against endotoxin-induced foetal resorptions, reducing the percentage of resorbed foetuses from 52.9 to 26.0% when given at a dose of 50 mg/kg (s.c.) at the time of endotoxin inoculation and 24 and 48 h following. Both these compounds also significantly reduced the increase in spleen weights observed when the mice were given endotoxin. These results provide evidence that the iron-catalysed production of hydroxyl radicals from other oxygen-derived species and the formation of leukotrienes play an important role in the mechanism by which endotoxin causes foetal resorptions in the mouse. PMID:2205283

  18. Endotoxin exposure and changes in short-term pulmonary function among sewage workers.

    PubMed

    Cyprowski, Marcin; Sobala, Wojciech; Buczyńska, Alina; Szadkowska-Stańczyk, Irena

    2015-01-01

    The inhaled endotoxin is considered as a causative factor in the process of acute bronchial obstruction, which can be measured by a decrease in forced expiratory volume in 1 s (FEV1). The aim of this study was to assess endotoxin exposure among sewage treatment plant workers (STPW) and its effect on across-shift changes in respiratory airflow. A group of 78 STPW from a large sewage treatment plant was studied. Inhalable dust for endotoxin assessment was collected using personal aerosol samplers. Endotoxin was assayed with the kinetic, chromogenic Limulus amebocyte lysate test. Across-shift spirometric measurements were performed on Mondays, after 2-days absence from work, with the use of portable spirometer. The forced vital capacity (FVC), and FEV1 parameters were analyzed. Multifactor regression modeling was performed to determine parameters significantly associated with endotoxin exposure. The concentration of inhalable dust and endotoxin ranged from 0.01-1.38 mg/m3 and 0.68-214 endotoxin units per cubic meter of air (EU/m3), respectively. Endotoxins were characterized with the skewed distribution (arithmetic mean (AM) = 38.8 EU/m3, geometric mean (GM) = 15.4 EU/m3, geometric standard deviation (GSD) = 4.21). Through the use of multifactor analysis, which excluded the main confounders (inhalable dust and smoking habit) it was found that, despite low levels of endotoxin, it had significant impact on the observed across-shift decline in FEV1 (p = 0.044). For this parameter, the regression slope was additionally calculated (r = -0.017, p = 0.071). Relatively low levels of endotoxin among sewage treatment plant workers may cause small, but significant across-shift declines in FEV1. The observed relationship was independent of organic dust concentrations and smoking habit. The respiratory protection should be provided for STPW. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  19. Production of recombinant allergens in plants

    PubMed Central

    2010-01-01

    A large percentage of allergenic proteins are of plant origin. Hence, plant-based expression systems are considered ideal for the recombinant production of certain allergens. First attempts to establish production of plant-derived allergens in plants focused on transient expression in Nicotiana benthamiana infected with recombinant viral vectors. Accordingly, allergens from birch and mugwort pollen, as well as from apple have been expressed in plants. Production of house dust mite allergens has been achieved by Agrobacterium-mediated transformation of tobacco plants. Beside the use of plants as production systems, other approaches have focused on the development of edible vaccines expressing allergens or epitopes thereof, which bypasses the need of allergen purification. The potential of this approach has been convincingly demonstrated for transgenic rice seeds expressing seven dominant human T cell epitopes derived from Japanese cedar pollen allergens. Parallel to efforts in developing recombinant-based diagnostic and therapeutic reagents, different gene-silencing approaches have been used to decrease the expression of allergenic proteins in allergen sources. In this way hypoallergenic ryegrass, soybean, rice, apple, and tomato were developed. PMID:21258627

  20. Production of recombinant allergens in plants.

    PubMed

    Schmidt, Georg; Gadermaier, Gabriele; Pertl, Heidi; Siegert, Marc; Oksman-Caldentey, Kirsi-Marja; Ritala, Anneli; Himly, Martin; Obermeyer, Gerhard; Ferreira, Fatima

    2008-10-01

    A large percentage of allergenic proteins are of plant origin. Hence, plant-based expression systems are considered ideal for the recombinant production of certain allergens. First attempts to establish production of plant-derived allergens in plants focused on transient expression in Nicotiana benthamiana infected with recombinant viral vectors. Accordingly, allergens from birch and mugwort pollen, as well as from apple have been expressed in plants. Production of house dust mite allergens has been achieved by Agrobacterium-mediated transformation of tobacco plants. Beside the use of plants as production systems, other approaches have focused on the development of edible vaccines expressing allergens or epitopes thereof, which bypasses the need of allergen purification. The potential of this approach has been convincingly demonstrated for transgenic rice seeds expressing seven dominant human T cell epitopes derived from Japanese cedar pollen allergens. Parallel to efforts in developing recombinant-based diagnostic and therapeutic reagents, different gene-silencing approaches have been used to decrease the expression of allergenic proteins in allergen sources. In this way hypoallergenic ryegrass, soybean, rice, apple, and tomato were developed.

  1. [Indoor air studies of mould fungus contamination of homes of selected patients with bronchial asthma (with special regard to evaluation problems)].

    PubMed

    Senkpiel, K; Kurowski, V; Ohgke, H

    1996-02-01

    Investigations of indoor air of the homes of seven patients with asthma bronchiale who showed up with positive reactions following intracutaneous application of fungal allergens revealed that their places of residence were contaminated by fungal and bacterial spores. The number of colony forming units of mesophilic fungal spores of the indoor air ranged from 100 to 1000 CFU/m3 and this was much higher than the mould flora of the outdoor air determined simultaneously. The major fungi species found by the indoor investigation were: Penicillium sp. > Aspergillus sp. > Cladosporium sp., Mucor sp., Chrysonilia sp., Verticillium sp. > Geotrichum sp., Trichoderma sp. In two cases Thermoactinomyces species could be detected in the indoor air. The main cause of fungal contamination were moist building materials on room walls, insufficient air ventilation, bad maintenance of the circulating air-machines and insufficient room hygiene (e.g. biological garbage in the kitchen).

  2. Endotoxin contamination and control in surface water sources and a drinking water treatment plant in Beijing, China.

    PubMed

    Can, Zhang; Wenjun, Liu; Wen, Sun; Minglu, Zhang; Lingjia, Qian; Cuiping, Li; Fang, Tian

    2013-07-01

    In this paper, endotoxin contamination was determined in treated water following each unit of a drinking water treatment plant (WTP) in Beijing, China and its source water (SW) from a long water diversion channel (Shijiazhuang-Beijing) originating from four reservoirs in Hebei province, China. The total-endotoxin activities in SW ranged from 21 to 41 EU/ml at five selected cross sections of the diversion channel. The total-endotoxin in raw water of the WTP ranged from 11 to 16 EU/ml due to dilution and pretreatment during water transportation from Tuancheng Lake to the WTP, and finished water of the WTP ranged from 4 to 10 EU/ml, showing a 49% decrease following the full-scale treatment process at the WTP. Compared with the 31% removal of free-endotoxin, the WTP removed up to 71% of bound-endotoxin in raw water. The traditional treatment processes (coagulation, sedimentation and filtration) in the WTP removed substantial amounts of total-endotoxin (up to 63%), while endotoxin activities increased after granular activated carbon (GAC) adsorption and chlorination. The total-endotoxin in the actual water was composed of free-endotoxin and bound-endotoxin (endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins). The endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins co-exist as suspended particles in water, and only the bacteria-bound endotoxins were correlated with bacterial cells suspended in water. The particle distribution of endotoxin aggregates in ultrapure water was also tested and the results showed that the majority (64-89%) of endotoxin aggregates had diameters <2 μm. The endotoxin contamination and control in treated water following each unit of the WTP processes and its SW from reservoirs are discussed and compared with regard to bacterial cell counts and particle characteristics, which were dependent, to a certain extent, on different flow rates and turbulence of the water environments. Copyright

  3. [Evaluation of the total biological activity and allergenic composition of allergenic extracts].

    PubMed

    Lombardero, M; González, R; Duffort, O; Juan, F; Ayuso, R; Ventas, P; Cortés, C; Carreira, J

    1986-01-01

    In the present study, a complete procedure is presented in order to standardize allergenic extracts, the meaning of which is the measurement of the total allergenic activity and the determination of the allergenic composition. The measurement of the biological activity comprises 2 steps: Preparation of Reference Extracts and determination of their "in vivo" activity. Evaluation of the total allergenic activity of extracts for clinical use. Reference extracts were prepared from the main allergens and their "in vivo" biological activity was determined by a quantitative skin prick test in a sample of at least 30 allergic patients. By definition, the protein concentration of Reference Extract that produces, in the allergic population, a geometric mean wheal of 75 mm.2 has an activity of 100 biological units (BUs). The determination of the biological activity of a problem extract is made by RAST inhibition. The sample is compared with the corresponding Reference Extract by this technique and, from this comparison, it is possible to quantify the activity of the problem extract in biologic units (BUs) with clinical significance. Likewise, different techniques have been used to determine the allergenic composition of extracts. These techniques comprise 2 steps: Separation of the components of the extract. Identification of the components that bind specific human IgE. The separation of the components of the extract has been carried out by isoelectric focusing (IEF) and electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE). In order to identify the allergenic components, an immunoblotting technique has been employed. The separated components in the IEF gel or SDS-PAGE gel are transferred to a nitrocellulose sheet and later on, this membrane is overlaid with a serum pool from allergic patients and a mouse monoclonal anti-human IgE, labelled with 125I. Finally, the autoradiography of the nitrocellulose membrane is obtained. In this way it is possible to compare

  4. Polymyxin B-immobilized fiber column hemoperfusion removes endotoxin throughout a 24-hour treatment period.

    PubMed

    Mitaka, Chieko; Fujiwara, Naoto; Yamamoto, Mamoru; Toyofuku, Takahiro; Haraguchi, Go; Tomita, Makoto

    2014-10-01

    The purpose of this study was to evaluate the extent of endotoxin adsorption by polymyxin B-immobilized fiber column hemoperfusion (PMX) performed for a 24-hour treatment period in patients with septic shock. Nineteen patients with septic shock were retrospectively studied. The plasma endotoxin concentrations of blood drawn from the radial artery and from the outlet circuit of the PMX column were measured by kinetic turbidimetric limulus assay using an MT-358 Toxinometer (Wako Pure Chemical Industries, Ltd, Osaka, Japan) after 24 hours of PMX treatment. The endotoxin removal rate was defined by the following equation: ([radial artery endotoxin concentration - outlet circuit of PMX column endotoxin concentration]/radial artery endotoxin concentration) × 100%. The patients had a median Acute Physiology and Chronic Health Evaluation II score of 29 at intensive care unit admission and a 28-day mortality of 47%. Before the start of the PMX treatment, the median radial arterial plasma endotoxin concentration was 16.48 pg/mL. After 24 hours of PMX treatment, the median radial plasma endotoxin concentration had decreased to 1.857 pg/mL, and the concentration at the outlet circuit of the PMX column was further decreased to 0.779 pg/mL. The median endotoxin removal rate was 74.4%. These findings suggest that 24-hour PMX treatment was effective in removing endotoxin continuously throughout the entire treatment period. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Experimental Study on Inactivation of Bacterial Endotoxin by Using Dielectric Barrier Discharge

    NASA Astrophysics Data System (ADS)

    Shi, Xingmin; Li, Yaxi; Zhang, Guanjun; Ma, Yue; Shao, Xianjun

    2011-12-01

    The low-temperature plasma (LTP) generated by dielectric barrier discharge (DBD) was used to sterilize the E.coli endotoxin, which is usually difficult to kill by traditional methods. Three different concentrations of bacterial endotoxin (1 EU/mL, 0.5 EU/mL and 0.25 EU/mL) were treated by LTP for different time (20 s, 40 s and 60 s). Tachypleus amebocyte lysate (TAL) method was employed to detect the concentration variation of bacterial endotoxin before and after the plasma treatment, and endotoxic shock mice model was used to evaluate the inactivation effects of LTP on endotoxin for further study. Experimental results demonstrated that, DBD plasma can inactivate the bacterial endotoxin quickly and effectively, and when the LTP treatment time was increased, the concentrations of bacterial endotoxin decreased gradually (after 60 s plasma treatment, its inactivation effect was beyond the Chinese pharmacopoeia standard), and the average survival time of mice gradually extended. The possible inactivation mechanisms are proposed to be related to reactive oxygen species (ROSs).

  6. The natural immunity to evolutionary atavistic endotoxin for human cancer.

    PubMed

    Moncevičiūtė-Eringienė, Elena; Rotkevič, Kristina; Grikienis, Ruta Grikienyte

    2015-11-01

    We propose a new theory of the immunological control of cancer corresponding to the hypothesis that the specific natural immunity to evolutionary atavistic endotoxin has a potential role in human cancer prevention. The results of our studies have shown that IgMNAE, i.e. endogenous or spontaneous IgM class antibodies to enterobacterial lipopolysaccharide molecules (lipid A), control the immune mechanisms responsible for the internal medium stability not only against the damaging impact of the carcinogenic factors, but also against the malignant transformation of its own degenerated cells. Among people who in 1979 and 1982 had IgMNAE in their blood serum, after 15-30years fell ill with cancer 10%, versus 15% among people who had no IgMNAE (p<0.05). Therefore, it is possible to maintain that the stimulation of IgMNAE synthesis would help in the destruction and elimination of damaged somatic cells or prevent their mechanisms from the formation of invasiveness, metastatic and other properties of their parasitism. In the mechanism of the natural immunity to endotoxin it is possible to see the formation of the respective evolutionary protective reactions which protect the damaged cells from acquiring resistance to damaging factors and thus from becoming an independent new parasitic population. Thereby the presented theory of the immunological control of cancer has a causal connection with our evolutionary resistance theory of the origin of cancer. Collectively, these data suggest that activation of natural immunity to endotoxin and production of vaccines against evolutionary atavistic endotoxin or gram-negative bacterial endotoxin can be helpful when applied in cancer prophylaxis for persons with a low level of natural immunity to endotoxin and perhaps in creating immunotherapeutic methods for stopping the endogenous parasitism of tumour cells by binding IgMNAE to atavistic endotoxin in cancer patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Bacterial endotoxin adhesion to different types of orthodontic adhesives

    PubMed Central

    ROMUALDO, Priscilla Coutinho; GUERRA, Thaís Rodrigues; ROMANO, Fábio Lourenço; da SILVA, Raquel Assed Bezerra; BRANDÃO, Izaíra Tincani; SILVA, Célio Lopes; da SILVA, Lea Assed Bezerra; NELSON-FILHO, Paulo

    2017-01-01

    Abstract Bacterial endotoxin (LPS) adhesion to orthodontic brackets is a known contributing factor to inflammation of the adjacent gingival tissues. Objective The aim of this study was to assess whether LPS adheres to orthodontic adhesive systems, comparing two commercial brands. Material and Methods Forty specimens were fabricated from Transbond XT and Light Bond composite and bonding agent components (n=10/component), then contaminated by immersion in a bacterial endotoxin solution. Contaminated and non-contaminated acrylic resin samples were used as positive and negative control groups, respectively. LPS quantification was performed by the Limulus Amebocyte Lysate QCL-1000™ test. Data obtained were scored and subjected to the Chi-square test using a significance level of 5%. Results There was endotoxin adhesion to all materials (p<0.05). No statistically significant difference was found between composites/bonding agents and acrylic resin (p>0.05). There was no significant difference (p>0.05) among commercial brands. Affinity of endotoxin was significantly greater for the bonding agents (p=0.0025). Conclusions LPS adhered to both orthodontic adhesive systems. Regardless of the brand, the endotoxin had higher affinity for the bonding agents than for the composites. There is no previous study assessing the affinity of LPS for orthodontic adhesive systems. This study revealed that LPS adheres to orthodontic adhesive systems. Therefore, additional care is recommended to orthodontic applications of these materials. PMID:28877283

  8. In vivo quantitation of the rat liver's ability to eliminate endotoxin from portal vein blood

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

    Yamaguchi, Y.; Yamaguchi, K.; Babb, J.L.

    The in vivo uptake of endotoxin by the liver from portal vein blood was assessed during a single passage through the liver. /sup 51/Cr labeled and unlabeled endotoxin were infused in different amounts into the femoral vein of three groups of lead-sensitized rats: a nonoperated, a sham-operated, and a surgically created reversed Eck fistula (REF) group. Whereas in the former two the infused endotoxin encounters the lung as the first filter organ, the liver performs this function in the latter experimental model. The mortality rates observed in control and sham-operated, lead-sensitized rats were found to correlate closely and reproducibly tomore » the degree of endotoxemia. This assay was then applied to determine the amount of endotoxin eliminated by the liver by establishing, in the REF rat, the amounts of endotoxin that escaped hepatic clearance. The capacity of the liver to eliminate endotoxin from portal vein blood during a single passage increases as the portal vein endotoxin level rises; it approaches a maximum, suggesting that endotoxin's interaction with the Kupffer cells conforms to classical saturation kinetics. A Lineweaver-Burk plot prepared from these data indicates that the maximal in vivo capacity of the liver to remove endotoxin from portal vein blood approximates 1.5 micrograms/gm liver/hr. Data obtained with the use of radiolabeled endotoxin corroborate the information obtained with the bioassay technique. Endotoxin eliminated by the Kupffer cells in these quantities is slowly disintegrated; 4 hr after termination of the endotoxin infusion, less than 4% of the radiolabel is found in the urine and none in the bile. These observations indicate that the Kupffer cell's functional capacity to sequester and detoxify endotoxin is extensive and far exceeds the requirements imposed by physiological and most pathological conditions.« less

  9. Chemical modification of birch allergen extract leads to a reduction in allergenicity as well as immunogenicity.

    PubMed

    Würtzen, Peter Adler; Lund, Lise; Lund, Gitte; Holm, Jens; Millner, Anders; Henmar, Helene

    2007-01-01

    In Europe, specific immunotherapy is currently conducted with vaccines containing allergen preparations based on intact extracts. In addition to this, chemically modified allergen extracts (allergoids) are used for specific allergy treatment. Reduced allergenicity and thereby reduced risk of side effects in combination with retained ability to activate T cells and induce protective allergen-specific antibody responses has been claimed for allergoids. In the current study, we compared intact allergen extracts and allergoids with respect to allergenicity and immunogenicity. The immunological response to birch allergen extract, alum-adsorbed extract, birch allergoid and alum-adsorbed allergoid was investigated in vitro in human basophil histamine release assay and by stimulation of human allergen-specific T cell lines. In vivo, Bet v 1-specific IgG titers in mice were determined after repetitive immunizations. In all patients tested (n = 8), allergoid stimulations led to reduced histamine release compared to the intact allergen extract. However, the allergoid preparations were not recognized by Bet v 1-specific T cell lines (n = 7), which responded strongly to the intact allergen extract. Mouse immunizations showed a clearly reduced IgG induction by allergoids and a strongly potentiating effect of the alum adjuvant. Optimal IgG titers were obtained after 3 immunizations with intact allergen extracts, while 5 immunizations were needed to obtain maximal response to the allergoid. The reduced histamine release observed for allergoid preparations may be at the expense of immunological efficacy because the chemical modifications lead to a clear reduction in T cell activation and the ability to induce allergen-specific IgG antibody responses. Copyright 2007 S. Karger AG, Basel.

  10. Personal Exposure to Particulate Matter and Endotoxin in California Dairy Workers

    NASA Astrophysics Data System (ADS)

    Garcia, Johnny

    The average number of cows per dairy has increased over the last thirty years, with little known about how this increase may impact occupational exposure. Thirteen California dairies and 226 workers participated in this study throughout the 2008 summer months. Particulate Matter (PM) and endotoxin concentrations were quantified using ambient area based and personal air samplers. Two size fractions were collected, Total Suspended Particulate matter (TSP) and PM 2.5. Differences across dairies were evaluated by placing area based integrated air samplers in established locations on the dairies, e.g. milking parlor, drylot corral, and freestall barns. The workers occupational exposure was quantified using personal air samplers. We analyzed concentrations along with the time workers spent conducting specific job tasks during their shift to identify high exposure job tasks. Biological and chemical analytical methods were employed to ascertain endotoxin concentrations in personal and area based air samples. Recombinant factor C assays (rFC) were used to analyze biologically active endotoxin and gas chromatography coupled with mass spectrometry in tandem (GC-MS/MS) was used to quantify total endotoxin. The PM2.5 concentrations ranged from 2-116 mug/m3 for ambient area concentration and 7-495 mug/m3 for personal concentrations while TSP concentrations ranged from 74-1690 mug/m3 for area ambient concentrations and 191-4950 mug/m3 for personal concentrations. Biologically active endotoxin concentrations in the TSP size fraction from ambient area based samples ranged from 11-2095 EU/m3 and 45-2061 EU/m3 for personal samples. Total endotoxin in the TSP size fraction ranged from 75-10,166 pmol/m3 for area based samples and 34-11,689 pmol/m3 for personal samples. Drylot corrals were found to have higher sample mean concentrations when compared to other locations on the dairies for PM and endotoxin. Re-bedding, of the freestalls, was found to consistently lead to higher personal

  11. Allergenicity, immunogenicity and dose-relationship of three intact allergen vaccines and four allergoid vaccines for subcutaneous grass pollen immunotherapy

    PubMed Central

    Henmar, H; Lund, G; Lund, L; Petersen, A; Würtzen, P A

    2008-01-01

    Different vaccines containing intact allergens or chemically modified allergoids as active ingredients are commercially available for specific immunotherapy. Allergoids are claimed to have decreased allergenicity without loss of immunogenicity and this is stated to allow administration of high allergoid doses. We compared the allergenicity and immunogenicity of four commercially available chemically modified grass pollen allergoid products with three commercially available intact grass pollen allergen vaccines. The allergenicity was investigated with immunoglobulin (Ig)E-inhibition and basophil activation assays. Human T cell proliferation and specific IgG-titres following mouse immunizations were used to address immunogenicity. Furthermore, intact allergen vaccines with different contents of active ingredients were selected to study the influence of the allergen dose. In general, a lower allergenicity for allergen vaccines was clearly linked to a reduced immunogenicity. Compared with the vaccine with the highest amount of intact allergen, the allergoids caused reduced basophil activation as well as diminished immunogenicity demonstrated by reduced T cell activation and/or reduced induction of murine grass-specific IgG antibodies. Interestingly, intact allergen vaccines with lower content of active ingredient exhibited similarly reduced allergenicity, while immunogenicity was still higher or equal to that of allergoids. The low allergenicity observed for some allergoids was inherently linked to a significantly lower immunogenic response questioning the rationale behind the chemical modification into allergoids. In addition, the linkage between allergenicity, immunogenicity and dose found for intact allergen vaccines and the immunogen as well as allergenic immune responses observed for allergoids suggest that the modified allergen vaccines do not contain high doses of immunologically active ingredients. PMID:18647321

  12. Allergenicity, immunogenicity and dose-relationship of three intact allergen vaccines and four allergoid vaccines for subcutaneous grass pollen immunotherapy.

    PubMed

    Henmar, H; Lund, G; Lund, L; Petersen, A; Würtzen, P A

    2008-09-01

    Different vaccines containing intact allergens or chemically modified allergoids as active ingredients are commercially available for specific immunotherapy. Allergoids are claimed to have decreased allergenicity without loss of immunogenicity and this is stated to allow administration of high allergoid doses. We compared the allergenicity and immunogenicity of four commercially available chemically modified grass pollen allergoid products with three commercially available intact grass pollen allergen vaccines. The allergenicity was investigated with immunoglobulin (Ig)E-inhibition and basophil activation assays. Human T cell proliferation and specific IgG-titres following mouse immunizations were used to address immunogenicity. Furthermore, intact allergen vaccines with different contents of active ingredients were selected to study the influence of the allergen dose. In general, a lower allergenicity for allergen vaccines was clearly linked to a reduced immunogenicity. Compared with the vaccine with the highest amount of intact allergen, the allergoids caused reduced basophil activation as well as diminished immunogenicity demonstrated by reduced T cell activation and/or reduced induction of murine grass-specific IgG antibodies. Interestingly, intact allergen vaccines with lower content of active ingredient exhibited similarly reduced allergenicity, while immunogenicity was still higher or equal to that of allergoids. The low allergenicity observed for some allergoids was inherently linked to a significantly lower immunogenic response questioning the rationale behind the chemical modification into allergoids. In addition, the linkage between allergenicity, immunogenicity and dose found for intact allergen vaccines and the immunogen as well as allergenic immune responses observed for allergoids suggest that the modified allergen vaccines do not contain high doses of immunologically active ingredients.

  13. Endotoxin and cancer chemo-prevention.

    PubMed

    Mastrangelo, Giuseppe; Fadda, Emanuela; Cegolon, Luca

    2013-10-01

    Reduced rates of lung cancer have been observed in several occupational groups exposed to high levels of organic dusts contaminated by endotoxin. The underlying anti-neoplastic mechanism of endotoxin may be an increased secretion of endogenous anti-neoplastic mediators and activation of the toll-like receptors (TLR). A detoxified endotoxin derivative, Monophosphoryl Lipid A (MPL(®)) is marketed in Europe since 1999 as part of the adjuvant systems in allergy vaccines for treatment of allergic rhino-conjunctivitis and allergic asthma. Over 200,000 patients have used them to date (nearly 70% in Germany). Since detailed exposure (MPL(®) dose and timing of administration) and individual data are potentially available, an observational follow-up study could be conducted in Germany to investigate the protective effect of MPL(®) against cancer, comparing cancer incidence in two groups of patients with allergic rhinitis: those treated with allergoids plus MPL(®) and those treated with a vaccine including the same allergoids but not MPL(®). The protective effect of MPL(®) could be quantified in ever and never smokers. If this proposed observational study provides evidence of protective effects, MPL(®) could be immediately used as a chemo-preventive agent since it is already in use as adjuvant in human vaccines against cancer. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Effect of Tris-acetate buffer on endotoxin removal from human-like collagen used biomaterials.

    PubMed

    Zhang, Huizhi; Fan, Daidi; Deng, Jianjun; Zhu, Chenghui; Hui, Junfeng; Ma, Xiaoxuan

    2014-09-01

    Protein preparation, which has active ingredients designated for the use of biomaterials and therapeutical protein, is obtained by genetic engineering, but products of genetic engineering are often contaminated by endotoxins. Because endotoxin is a ubiquitous and potent proinflammatory agent, endotoxin removal or depletion from protein is essential for researching any biomaterials. In this study, we have used Tris-acetate (TA) buffer of neutral pH value to evaluate endotoxins absorbed on the Pierce high-capacity endotoxin removal resin. The effects of TA buffer on pH, ionic strength, incubation time as well as human-like collagen (HLC) concentration on eliminating endotoxins are investigated. In the present experiments, we design an optimal method for TA buffer to remove endotoxin from recombinant collagen and use a chromogenic tachypleus amebocyte lysate (TAL) test kit to measure the endotoxin level of HLC. The present results show that, the endotoxins of HLC is dropped to 8.3EU/ml at 25 mM TA buffer (pH7.8) with 150 mM NaCl when setting incubation time at 6h, and HLC recovery is about 96%. Under this experimental condition, it is proved to exhibit high efficiencies of both endotoxin removal and collagen recovery. The structure of treated HLC was explored by Transmission Electron Microscopy (TEM), demonstrating that the property and structure of HLC treated by TA buffer are maintained. Compared to the most widely used endotoxin removal method, Triton X-114 extraction, using TA buffer can obtain the non-toxic HLC without extra treatment for removing the toxic substances in Triton X-114. In addition, the present study aims at establishing a foundation for further work in laboratory animal science and providing a foundation for medical grade biomaterials. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. High-dose recombinant endotoxin neutralizing protein improves survival in rabbits, with Escherichia coli sepsis.

    PubMed

    Saladino, R A; Stack, A M; Thompson, C; Sattler, F; Novitsky, T J; Siber, G R; Fleisher, G R

    1996-07-01

    To assess the benefit of a recombinant endotoxin neutralizing protein from Limulus polyphemus in treating Gram-negative bacterial sepsis in rabbits. Prospective, blinded, controlled, laboratory trial. Animal research laboratory. New Zealand White rabbits. We established a rabbit model of Escherichia coli peritonitis and bacteremia, with high mortality rate, despite treatment with gentamicin and ceftriaxone. Twenty-five pairs of male New Zealand White rabbits were challenged intraperitoneally with E. coli O18ac K1 in 5% porcine mucin (mean 7 x 10(1) colony-forming units). All animals were treated with intravenous gentamicin (2.5 mg/kg) and ceftriaxone (100 mg/kg), and with either intravenous endotoxin neutralizing protein (50 mg/kg) or saline 1 hr after E. coli challenge. All animals were bacteremic 1 hr after challenge (mean 3.6 x 10(5) colony-forming units/mL). Animals in both groups developed tachycardia, hypotension, and acidosis (NS). Geometric mean serum endotoxin and tumor necrosis factor (TNF) concentrations were significantly ( p < .001) higher 1 hr after challenge compared with baseline prechallenge concentrations in both groups. From 1 to 2 hrs after challenge, endotoxin concentrations increased 2.5-fold in control animals (95% confidence interval = 13.1 to 32.9 endotoxin units/mL, p = .024), whereas endotoxin concentrations increased only 1.2-fold in endotoxin neutralizing protein-treated animals (95% confidence interval = 20.4 to 23.6 endotoxin units/mL, NS). TNF concentrations increased significantly (p < .001) in both groups from 1 to 2 hrs after challenge. Eighteen (72%) of 25 endotoxin neutralizing protein-treated animals vs. 11 (44%) of 25 controls survived 24 hrs (p = .032). Treatment with endotoxin neutralizing protein had the following effects: a) the increase in serum endotoxin was blunted, but not TNF concentrations measured 1 hr after antibiotic treatment; and b) survival in rabbits with E. Coli sepsis was improved.

  16. Bioactive and total endotoxins in atmospheric aerosols in the Pearl River Delta region, China

    NASA Astrophysics Data System (ADS)

    Cheng, Jessica Y. W.; Hui, Esther L. C.; Lau, Arthur P. S.

    2012-02-01

    Endotoxin, a toxic and pyrogenic substance in gram-negative bacteria in atmospheric aerosols was measured over a period of one year at Nansha, Guangzhou and Hong Kong in the Pearl River Delta region, China. Atmospheric aerosols were collected by high-volume samplers. The bioactive endotoxin levels in the samples were determined using the Limulus Amebocyte Lysate (LAL) assay after extraction with pyrogen-free water while the total endotoxin levels were measured by quantifying the biomarker, 3-hydroxy fatty acids (3-OHFAs) with GC-MS. Results showed that there was no significant difference (0.19 < p < 0.81) in the bioactive endotoxin level in PM 10 among sites (average concentrations ranged from 0.34 to 0.39 EU m -3). However, Hong Kong showed a significantly lower ( p < 0.05) total endotoxin level in PM 10 (average of 17.4 ng m -3) compared with Nansha's 29.4 ng m -3 and Guangzhou's 32.7 ng m -3. The bioactive endotoxins were found to be associated with the coarse mode (PM 2.5-10) of the particulates of natural origins while the total endotoxins were associated more with the fine mode (PM 2.5) of the particulates of anthropogenic origins. When normalized with particulate mass, the endotoxin loading is much higher in summer as a result of the increased growth of the bacteria when climatic conditions are favorable. The chemically determined total endotoxins were 3-4 orders of magnitude higher than the bioactive endotoxins quantified using the LAL assay. Correlation analyses between the bioactive endotoxins and 3-OHFAs with different carbon length were analyzed. Results showed that the correlations detected vary among sites and particulate sizes. Although no generalization between the total and bioactive endotoxins can be drawn from the study, the levels reported in this study suggests that the discrepancies between the two measurement approaches, and the bioactive potential of 3-OHFAs with individual carbon chains deserve further investigation.

  17. EFFECTS OF LIME (CAO) ON THE ENDOTOXIN LEVELS OF BIOSOLIDS

    EPA Science Inventory

    Lime addition is a common practice for treating biosolids in order to meet EPA 503 requirements for land application. Since this treatment kills the majority of microorganisms, will it increase the level of endotoxins present in biosolids? And, if endotoxin levels are increased, ...

  18. Immunotherapy with Allergen Peptides

    PubMed Central

    2007-01-01

    Specific allergen immunotherapy (SIT) is disease-modifying and efficacious. However, the use of whole allergen preparations is associated with frequent allergic adverse events during treatment. Many novel approaches are being designed to reduce the allergenicity of immunotherapy preparations whilst maintaining immunogenicity. One approach is the use of short synthetic peptides which representing dominant T cell epitopes of the allergen. Short peptides exhibit markedly reduced capacity to cross link IgE and activate mast cells and basophils, due to lack of tertiary structure. Murine pre-clinical studies have established the feasibility of this approach and clinical studies are currently in progress in both allergic and autoimmune diseases. PMID:20525144

  19. Mercaptoethanol-resistant human serum antibodies reacting with endotoxin from Neisseria gonorrhoeae.

    PubMed Central

    Maeland, J A; Larsen, B

    1975-01-01

    Sera from fifty patients with gonorrhoea, thirty with non-specific urethritis, and eighty blood donors were treated with mercaptoethanol (ME) and examined by the indirect haemagglutination test for antibodies against endotoxin from gonococci. Erythrocytes sensitized with determinant a of endotoxin from Strains 8551, V, and VII, or determinant b from Strain V were used. The percentage of sera active in the haemagglutination test was much higher in the gonorrhoea group than in the controls. The geometric mean titre was also significantly higher in the gonorrhoea group. This applied for all four antigens used. Results obtained in an anti-globulin test indicated that the titre of ME-treated serum was determined by IgG antibodies against the endotoxin. Many sera had titres which varied according to the strain origin of the antigen used in the test. The sensitivity of tests for antibodies was increased by using endotoxin from several different strains of gonococci for the examination of each serum. A simplified procedure for determination of antibodies against endotoxin from different strains of gonococci was elaborated. PMID:48404

  20. Endotoxin activity of Moraxella osloensis against the grey garden slug, Deroceras reticulatum.

    PubMed

    Tan, Li; Grewal, Parwinder S

    2002-08-01

    Moraxella osloensis is a gram-negative bacterium associated with Phasmarhabditis hermaphrodita, a slug-parasitic nematode that has prospects for biological control of mollusk pests, especially the grey garden slug, Deroceras reticulatum. This bacterium-feeding nematode acts as a vector that transports M. osloensis into the shell cavity of the slug, and the bacterium is the killing agent in the nematode-bacterium complex. We discovered that M. osloensis produces an endotoxin(s), which is tolerant to heat and protease treatments and kills the slug after injection into the shell cavity. Washed or broken cells treated with penicillin and streptomycin from 3-day M. osloensis cultures were more pathogenic than similar cells from 2-day M. osloensis cultures. However, heat and protease treatments and 2 days of storage at 22 degrees C increased the endotoxin activity of the young broken cells but not the endotoxin activity of the young washed cells treated with the antibiotics. This suggests that there may be a proteinaceous substance(s) that is structurally associated with the endotoxin(s) and masks its toxicity in the young bacterial cells. Moreover, 2 days of storage of the young washed bacterial cells at 22 degrees C enhanced their endotoxin activity if they were not treated with the antibiotics. Furthermore, purified lipopolysaccharide (LPS) from the 3-day M. osloensis cultures was toxic to slugs, with an estimated 50% lethal dose of 48 microg per slug, thus demonstrating that the LPS of M. osloensis is an endotoxin that is active against D. reticulatum. This appears to be the first report of a biological toxin that is active against mollusks.

  1. Endotoxin Activity of Moraxella osloensis against the Grey Garden Slug, Deroceras reticulatum

    PubMed Central

    Tan, Li; Grewal, Parwinder S.

    2002-01-01

    Moraxella osloensis is a gram-negative bacterium associated with Phasmarhabditis hermaphrodita, a slug-parasitic nematode that has prospects for biological control of mollusk pests, especially the grey garden slug, Deroceras reticulatum. This bacterium-feeding nematode acts as a vector that transports M. osloensis into the shell cavity of the slug, and the bacterium is the killing agent in the nematode-bacterium complex. We discovered that M. osloensis produces an endotoxin(s), which is tolerant to heat and protease treatments and kills the slug after injection into the shell cavity. Washed or broken cells treated with penicillin and streptomycin from 3-day M. osloensis cultures were more pathogenic than similar cells from 2-day M. osloensis cultures. However, heat and protease treatments and 2 days of storage at 22°C increased the endotoxin activity of the young broken cells but not the endotoxin activity of the young washed cells treated with the antibiotics. This suggests that there may be a proteinaceous substance(s) that is structurally associated with the endotoxin(s) and masks its toxicity in the young bacterial cells. Moreover, 2 days of storage of the young washed bacterial cells at 22°C enhanced their endotoxin activity if they were not treated with the antibiotics. Furthermore, purified lipopolysaccharide (LPS) from the 3-day M. osloensis cultures was toxic to slugs, with an estimated 50% lethal dose of 48 μg per slug, thus demonstrating that the LPS of M. osloensis is an endotoxin that is active against D. reticulatum. This appears to be the first report of a biological toxin that is active against mollusks. PMID:12147494

  2. Comparison of a recombinant endotoxin-neutralizing protein with a human monoclonal antibody to endotoxin for the treatment of Escherichia coli sepsis in rats.

    PubMed

    Kuppermann, N; Nelson, D S; Saladino, R A; Thompson, C M; Sattler, F; Novitsky, T J; Fleisher, G R; Siber, G R

    1994-09-01

    A recombinant endotoxin-neutralizing protein (ENP) from Limulus polyphemus and a monoclonal IgM anti-lipid A antibody (HA-1A) were compared in a rat model of Escherichia coli sepsis. One hour after intraperitoneal challenge with 10(6) cfu of E. coli O18ac K1, animals were sensitized to endotoxin with lead acetate and treated with ENP, HA-1A, or saline, followed by ceftriaxone and gentamicin. Before treatment, 95% of rats had high-grade bacteremia and high serum endotoxin concentrations, which were similar in all treatment groups (P > .60). One hour after treatment, there was no bacterial growth in any blood sample, and endotoxin concentrations were significantly lower in the ENP group than in the HA-1A and saline groups (P < .01). At 24 h after challenge, survival in the ENP group was significantly higher than in the HA-1A saline group (P < .001). ENP improved survival in a rat model of E. coli sepsis with high mortality despite effective antibiotic therapy.

  3. Natural rubber latex allergens: new developments.

    PubMed

    Yeang, Hoong-Yeet

    2004-04-01

    New allergenic latex proteins have been identified, whereas further information on known latex allergens has emerged in recent years. Although prevalence figures for sensitization to the various latex allergens have been published in several studies in the past, the data have not been collated to facilitate cross-comparison. Salient characteristics of the three most recently identified latex allergens, Hev b 11, 12 and 13 are described, whereas new findings on some of the previously recognized allergens are examined. Hev b 2 is viewed from the standpoint of allergenicity and protein glycosylation, Hev b 4 in relation to its biochemical identity and molecular cloning, Hev b 5 with respect to its recombinant form, and Hev b 6 in connection with conformational IgE epitopes. Reports on sensitization or allergic reaction to purified latex allergens from recent and past work are summarized. The use of latex allergens in latex allergy diagnostics is reviewed and discussed. Thirteen latex allergens have been recognized by the International Union of Immunological Societies. Based on the results of published studies, native Hev b 2, recombinant Hev b 5, native or recombinant Hev b 6, native Hev b 13, and possibly native Hev b 4 are the major allergens relevant to latex-sensitized adults. Although there is an increasing tendency to identify and characterize latex allergens largely on the basis of their recombinant forms, not all such recombinant proteins have been fully validated against their native counterparts with respect to clinical significance.

  4. Diagnostic potential of endotoxin scattering photometry for sepsis and septic shock.

    PubMed

    Shimizu, Tomoharu; Obata, Toru; Sonoda, Hiromichi; Akabori, Hiroya; Miyake, Tohru; Yamamoto, Hiroshi; Tabata, Takahisa; Eguchi, Yutaka; Tani, Tohru

    2013-12-01

    Endotoxin scattering photometry (ESP) is a novel Limulus amebocyte lysate (LAL) assay that uses a laser light-scattering particle-counting method. In the present study, we compared ESP, standard turbidimetric LAL assay, and procalcitonin assay for the evaluation of sepsis after emergency gastrointestinal surgery. A total of 174 samples were collected from 40 adult patients undergoing emergency gastrointestinal surgery and 10 patients with colorectal cancer undergoing elective surgery as nonseptic controls. Plasma endotoxin levels were measured with ESP and turbidimetric LAL assay, and plasma procalcitonin levels were assessed with a standard procalcitonin assay. Plasma endotoxin and procalcitonin levels increased corresponding to the degree of sepsis. Endotoxin scattering photometry significantly discriminated between patients with or without septic shock: sensitivity, 81.1%; specificity, 76.6%; positive predictive value, 48.4%; negative predictive value, 93.8%; and accuracy, 77.6%. The area under the receiver operating characteristic curve for septic shock with the ESP assay (endotoxin cutoff value, 23.8 pg/mL) was 0.8532 ± 0.0301 (95% confidence interval, 0.7841-0.9030; P < 0.0001). The predictive power of ESP was superior to that of turbidimetric assay (difference, 0.1965 ± 0.0588; 95% confidence interval, 0.0812-0.3117; P = 0.0008). There was no significant difference in predictive power between ESP and procalcitonin assay. Endotoxin scattering photometry also discriminated between patients with and without sepsis. Area under the receiver operating characteristic curve analysis showed that ESP had the best predictive power for diagnosing sepsis. In conclusion, compared with turbidimetric LAL assay, ESP more sensitively detected plasma endotoxin and significantly discriminated between sepsis and septic shock in patients undergoing gastrointestinal emergency surgery.

  5. Airborne environmental endotoxin: a cross-validation of sampling and analysis techniques.

    PubMed Central

    Walters, M; Milton, D; Larsson, L; Ford, T

    1994-01-01

    A standard method for measurement of airborne environmental endotoxin was developed and field tested in a fiberglass insulation-manufacturing facility. This method involved sampling with a capillary-pore membrane filter, extraction in buffer using a sonication bath, and analysis by the kinetic-Limulus assay with resistant-parallel-line estimation (KLARE). Cross-validation of the extraction and assay method was performed by comparison with methanolysis of samples followed by 3-hydroxy fatty acid (3-OHFA) analysis by gas chromatography-mass spectrometry. Direct methanolysis of filter samples and methanolysis of buffer extracts of the filters yielded similar 3-OHFA content (P = 0.72); the average difference was 2.1%. Analysis of buffer extracts for endotoxin content by the KLARE method and by gas chromatography-mass spectrometry for 3-OHFA content produced similar results (P = 0.23); the average difference was 0.88%. The source of endotoxin was gram-negative bacteria growing in recycled washwater used to clean the insulation-manufacturing equipment. The endotoxin and bacteria become airborne during spray cleaning operations. The types of 3-OHFAs in bacteria cultured from the washwater, present in the washwater and in the air, were similar. Virtually all of the bacteria cultured from air and water were gram negative composed mostly of two species, Deleya aesta and Acinetobacter johnsonii. Airborne countable bacteria correlated well with endotoxin (r2 = 0.64). Replicate sampling showed that results with the standard sampling, extraction, and Limulus assay by the KLARE method were highly reproducible (95% confidence interval for endotoxin measurement +/- 0.28 log10). These results demonstrate the accuracy, precision, and sensitivity of the standard procedure proposed for airborne environmental endotoxin. PMID:8161191

  6. Physical and biological properties of U. S. standard endotoxin EC after exposure to ionizing radiation

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

    Csako, G.; Elin, R.J.; Hochstein, H.D.

    Techniques that reduce the toxicity of bacterial endotoxins are useful for studying the relationship between structure and biological activity. We used ionizing radiation to detoxify a highly refined endotoxin preparation. U.S. standard endotoxin EC. Dose-dependent changes occurred by exposure to /sup 60/Co-radiation in the physical properties and biological activities of the endotoxin. Sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis showed gradual loss of the polysaccharide components (O-side chain and R-core) from the endotoxin molecules. In contrast, although endotoxin revealed a complex absorption pattern in the UV range, radiation treatment failed to modify that pattern. Dose-related destruction of the primary toxic component,more » lipid A, was suggested by the results of activity tests: both the pyrogenicity and limulus reactivity of the endotoxin were destroyed by increasing doses of radiation. The results indicate that the detoxification is probably due to multiple effects of the ionizing radiation on bacterial lipopolysaccharides, and the action involves (i) the destruction of polysaccharide moieties and possibly (ii) the alteration of lipid A component of the endotoxin molecule.« less

  7. Sensitization rates of causative allergens for dogs with atopic dermatitis: detection of canine allergen-specific IgE

    PubMed Central

    Kang, Min-Hee; Kim, Ha-Jung; Jang, Hye-Jin

    2014-01-01

    Allergen-specific IgE serology tests became commercially available in the 1980s. Since then these tests have been widely used to diagnose and treat allergic skin diseases. However, the relationship between a positive reaction and disease occurrence has been controversial. The purpose of this study was to evaluate allergens using a serologic allergy test in dogs with atopic dermatitis (AD). Dogs clinically diagnosed with AD (n=101) were tested using an allergen-specific IgE immunoassay. Among the total 92 environmental and food allergens, house dust and house dust mites were the most common. Several allergens including airborne pollens and molds produced positive reactions, and which was considered increasing allergens relating to the climate changes. The presence of antibodies against staphylococci and Malassezia in cases of canine AD was warranted in this study. Additionally, strong (chicken, turkey, brown rice, brewer's yeast, and soybean) and weakly (rabbit, vension, duck, and tuna) positive reactions to food allergens could be used for avoidance and limited-allergen trials. PMID:24962408

  8. Sensitization rates of causative allergens for dogs with atopic dermatitis: detection of canine allergen-specific IgE.

    PubMed

    Kang, Min-Hee; Kim, Ha-Jung; Jang, Hye-Jin; Park, Hee-Myung

    2014-12-01

    Allergen-specific IgE serology tests became commercially available in the 1980s. Since then these tests have been widely used to diagnose and treat allergic skin diseases. However, the relationship between a positive reaction and disease occurrence has been controversial. The purpose of this study was to evaluate allergens using a serologic allergy test in dogs with atopic dermatitis (AD). Dogs clinically diagnosed with AD (n = 101) were tested using an allergen-specific IgE immunoassay. Among the total 92 environmental and food allergens, house dust and house dust mites were the most common. Several allergens including airborne pollens and molds produced positive reactions, and which was considered increasing allergens relating to the climate changes. The presence of antibodies against staphylococci and Malassezia in cases of canine AD was warranted in this study. Additionally, strong (chicken, turkey, brown rice, brewer's yeast, and soybean) and weakly (rabbit, vension, duck, and tuna) positive reactions to food allergens could be used for avoidance and limited-allergen trials.

  9. Molecular aspects of allergens in atopic dermatitis

    PubMed Central

    Campana, Raffaela; Dzoro, Sheron; Mittermann, Irene; Fedenko, Elena; Elisyutina, Olga; Khaitov, Musa; Karaulov, Alexander; Valenta, Rudolf

    2017-01-01

    Purpose of review Molecular allergology uses pure, mainly recombinant and structurally defined allergen molecules and allergen-derived epitopes to study mechanisms of IgE-associated allergy, to diagnose, and even predict the development of allergic manifestations and to treat and prevent IgE-associated allergies. Atopic dermatitis, a chronic inflammatory skin disease is almost always associated with IgE sensitization to allergens. However, also non-IgE-mediated pathomechanisms seem to be operative in atopic dermatitis and it is often difficult to identify the disease-causing allergens. Here we review recent work showing the usefulness of molecular allergology to study mechanisms of atopic dermatitis, for diagnosis and eventually for treatment and prevention of atopic dermatitis. Recent findings IgE sensitization to airborne, food-derived, microbial allergens, and autoallergens has been found to be associated with atopic dermatitis. Using defined allergen molecules and non-IgE-reactive allergen derivatives, evidence could be provided for the existence of IgE- and non-IgE-mediated mechanisms of inflammation in atopic dermatitis. Furthermore, effects of epicutaneous allergen administration on systemic allergen-specific immune responses have been studied. Multi-allergen tests containing micro-arrayed allergen molecules have been shown to be useful for the identification of culprit allergens in atopic dermatitis and may improve the management of atopic dermatitis by allergen-specific immunotherapy, allergen avoidance, and IgE-targeting therapies in a personalized medicine approach. Summary Molecular allergology allows for dissection of the pathomechanisms of atopic dermatitis, provides new forms of allergy diagnosis for identification of disease-causing allergens, and opens the door to new forms of management by allergen-specific and T cells-targeting or IgE-targeting interventions in a personalized medicine approach. PMID:28622169

  10. Inhibiting Peanut Allergen Digestion with p-Aminobenzamidine Attached to the Allergens

    USDA-ARS?s Scientific Manuscript database

    Peanut allergens can be digested into peptide fragments despite being known as resistant proteins. Once absorbed, the peptide fragments from digested allergens could bind to immunoglobulin E (IgE) antibodies and cause an allergic reaction in allergic individuals. To reduce peanut allergy, one approa...

  11. Characteristic motifs for families of allergenic proteins

    PubMed Central

    Ivanciuc, Ovidiu; Garcia, Tzintzuni; Torres, Miguel; Schein, Catherine H.; Braun, Werner

    2008-01-01

    The identification of potential allergenic proteins is usually done by scanning a database of allergenic proteins and locating known allergens with a high sequence similarity. However, there is no universally accepted cut-off value for sequence similarity to indicate potential IgE cross-reactivity. Further, overall sequence similarity may be less important than discrete areas of similarity in proteins with homologous structure. To identify such areas, we first classified all allergens and their subdomains in the Structural Database of Allergenic Proteins (SDAP, http://fermi.utmb.edu/SDAP/) to their closest protein families as defined in Pfam, and identified conserved physicochemical property motifs characteristic of each group of sequences. Allergens populate only a small subset of all known Pfam families, as all allergenic proteins in SDAP could be grouped to only 130 (of 9318 total) Pfams, and 31 families contain more than four allergens. Conserved physicochemical property motifs for the aligned sequences of the most populated Pfam families were identified with the PCPMer program suite and catalogued in the webserver Motif-Mate (http://born.utmb.edu/motifmate/summary.php). We also determined specific motifs for allergenic members of a family that could distinguish them from non-allergenic ones. These allergen specific motifs should be most useful in database searches for potential allergens. We found that sequence motifs unique to the allergens in three families (seed storage proteins, Bet v 1, and tropomyosin) overlap with known IgE epitopes, thus providing evidence that our motif based approach can be used to assess the potential allergenicity of novel proteins. PMID:18951633

  12. Respiratory health effects of exposure to low levels of airborne endotoxin - a systematic review.

    PubMed

    Farokhi, Azadèh; Heederik, Dick; Smit, Lidwien A M

    2018-02-08

    Elevated endotoxin levels have been measured in ambient air around livestock farms, which is a cause of concern for neighbouring residents. There is clear evidence that occupational exposure to high concentrations of airborne endotoxin causes respiratory inflammation, respiratory symptoms and lung function decline. However, health effects of exposure to low levels of endotoxin are less well described. The aim of this systematic review is to summarize published associations between exposure to relatively low levels of airborne endotoxin and respiratory health endpoints. Studies investigating respiratory effects of measured or modelled exposure to low levels of airborne endotoxin (average < 100 EU/m 3 ) were eligible for inclusion. In total, 1362 articles were identified through a Pubmed database search, of which 31 articles were included in this review. Studies were included up to February 2017. Overview tables and forest plots were created, and study quality was assessed. Twenty-two included studies had a cross-sectional design, others were designed as longitudinal observational (n = 7) or experimental (n = 2) studies. Most studies (n = 23) were conducted in an occupational setting, some involved domestic or experimental exposure. Several studies reported statistically significant effects of exposure to low levels of endotoxin on respiratory symptoms and lung function. However, considerable heterogeneity existed in the outcomes of the included studies and no overall estimate could be provided by meta-analysis to quantify the possible relationship. Instead, a best evidence synthesis was performed among studies examining the exposure-response relationship between endotoxin and respiratory outcomes. Significant exposure-response relationships between endotoxin and symptoms and FEV 1 were shown in several studies, with no conflicting findings in the studies included in the best evidence synthesis. Significantly different effects of endotoxin exposure

  13. Concentration, physical state, and purity of bacterial endotoxin affect its detoxification by ionizing radiation

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

    Csako, G.; Tsai, C.M.; Hochstein, H.D.

    Increasing concentrations of a highly purified bacterial lipopolysaccharide preparation, the U.S. Reference Standard Endotoxin, were exposed to increasing doses of ionizing radiation from a 60Co source. At identical radiation doses both the structural change and Limulus amebocyte lysate (LAL) reactivity were progressively smaller with increasing concentrations of the lipopolysaccharide in an aqueous medium. Under the experimental conditions used, there was a linear relationship between the endotoxin concentration and radiation dose for the structural changes. In contrast to endotoxin in aqueous medium, endotoxin irradiated in its dry state showed no decrease in LAL reactivity and rabbit pyrogenicity. Endotoxin exposed to radiationmore » in water in the presence of albumin showed a much smaller decrease in LAL and pyrogenic activities than expected. The results show that the concentration, physical state, and purity of endotoxin influence its structural and functional alteration by ionizing radiation.« less

  14. Altered macrophage arachidonic acid metabolism induced by endotoxin tolerance: characterization and mechanisms

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

    Rogers, T.S.

    Altered macrophage arachidonic acid (AA) metabolism may play a role in endotoxic shock and the phenomenon of endotoxin tolerance induced by repeated injections of endotoxin. Studies were initiated to characterize both lipoxygenase and cyclooxygenase metabolite formation by endotoxin tolerant and non-tolerant macrophages in response to 4 different stimuli, i.e., endotoxin, glucan, zymosan, and the calcium ionophore A23187. In contrast to previous reports of decreased prostaglandin synthesis by tolerant macrophages, A23187-stimulated immunoreactive (i) leukotriene (LT) C/sub 4/D/sub 4/ and prostaglandin (PG) E/sub 2/ production by tolerant cells was greater than that by non-tolerant controls (p <0.001). However, A23187-stimulated i6-keto PGF/sub 1a/more » levels were lower in tolerant macrophages compared to controls (P < 0.05). iL TC/sub 4/D/sub 4/ production was not significantly stimulated by endotoxin or glucan, but was stimulated by zymosan in non-tolerant cells. Synthesis of iLTB/sub 4/ by control macrophages was stimulated by endotoxin (p <0.01). The effect of tolerance on factors that affect AA release was investigated by measuring /sup 14/C-AA incorporation and release and phospholipase A/sub 2/ activity« less

  15. Effect of endotoxin on ventilation and breath variability: role of cyclooxygenase pathway.

    PubMed

    Preas, H L; Jubran, A; Vandivier, R W; Reda, D; Godin, P J; Banks, S M; Tobin, M J; Suffredini, A F

    2001-08-15

    To evaluate the effects of endotoxemia on respiratory controller function, 12 subjects were randomized to receive endotoxin or saline; six also received ibuprofen, a cyclooxygenase inhibitor, and six received placebo. Administration of endotoxin produced fever, increased respiratory frequency, decreased inspiratory time, and widened alveolar-arterial oxygen tension gradient (all p < or = 0.001); these responses were blocked by ibuprofen. Independent of ibuprofen, endotoxin produced dyspnea, and it increased fractional inspiratory time, minute ventilation, and mean inspiratory flow (all p < or = 0.025). Endotoxin altered the autocorrelative behavior of respiratory frequency by increasing its autocorrelation coefficient at a lag of one breath, the number of breath lags with significant serial correlations, and its correlated fraction (all p < 0.05); these responses were blocked by ibuprofen. Changes in correlated behavior of respiratory frequency were related to changes in arterial carbon dioxide tension (r = 0.86; p < 0.03). Endotoxin decreased the oscillatory fraction of inspiratory time in both the placebo (p < 0.05) and ibuprofen groups (p = 0.06). In conclusion, endotoxin produced increases in respiratory motor output and dyspnea independent of fever and symptoms, and it curtailed the freedom to vary respiratory timing-a response that appears to be mediated by the cyclooxygenase pathway.

  16. Identifying risk factors for exposure to culturable allergenic moulds in energy efficient homes by using highly specific monoclonal antibodies

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

    Sharpe, Richard A.; Cocq, Kate Le; Nikolaou, Vasilis

    The aim of this study was to determine the accuracy of monoclonal antibodies (mAbs) in identifying culturable allergenic fungi present in visible mould growth in energy efficient homes, and to identify risk factors for exposure to these known allergenic fungi. Swabs were taken from fungal contaminated surfaces and culturable yeasts and moulds isolated by using mycological culture. Soluble antigens from cultures were tested by ELISA using mAbs specific to the culturable allergenic fungi Aspergillus and Penicillium spp., Ulocladium, Alternaria, and Epicoccum spp., Cladosporium spp., Fusarium spp., and Trichoderma spp. Diagnostic accuracies of the ELISA tests were determined by sequencing ofmore » the internally transcribed spacer 1 (ITS1)-5.8S-ITS2-encoding regions of recovered fungi following ELISA. There was 100% concordance between the two methods, with ELISAs providing genus-level identity and ITS sequencing providing species-level identities (210 out of 210 tested). Species of Aspergillus/Penicillium, Cladosporium, Ulocladium/Alternaria/Epicoccum, Fusarium and Trichoderma were detected in 82% of the samples. The presence of condensation was associated with an increased risk of surfaces being contaminated by Aspergillus/Penicillium spp. and Cladosporium spp., whereas moisture within the building fabric (water ingress/rising damp) was only associated with increased risk of Aspergillus/Penicillium spp. Property type and energy efficiency levels were found to moderate the risk of indoor surfaces becoming contaminated with Aspergillus/Penicillium and Cladosporium which in turn was modified by the presence of condensation, water ingress and rising damp, consistent with previous literature. - Highlights: • Monoclonal antibodies were used to track culturable allergenic moulds in homes. • Allergenic moulds were recovered from 82% of swabs from contaminated surfaces. • The mAbs were highly specific with 100% agreement to PCR of recovered fungi. • Improvements to

  17. Direct analysis of airborne mite allergen (Der f1) in the residential atmosphere by chemifluorescent immunoassay using bioaerosol sampler.

    PubMed

    Miyajima, Kumiko; Suzuki, Yurika; Miki, Daisuke; Arai, Moeka; Arakawa, Takahiro; Shimomura, Hiroji; Shiba, Kiyoko; Mitsubayashi, Kohji

    2014-06-01

    Dermatophagoides farinae allergen (Der f1) is one of the most important indoor allergens associated with allergic diseases in humans. Mite allergen Der f1 is usually associated with particles of high molecular weight; thus, Der f1 is generally present in settled dust. However, a small quantity of Der f1 can be aerosolized and become an airborne component. Until now, a reliable method of detecting airborne Der f1 has not been developed. The aim of this study was to develop a fiber-optic chemifluorescent immunoassay for the detection of airborne Der f1. In this method, the Der f1 concentration measured on the basis of the intensity of fluorescence amplified by an enzymatic reaction between the labeled enzyme by a detection antibody and a fluorescent substrate. The measured Der f1 concentration was in the range from 0.49 to 250 ng/ml and a similar range was found by enzyme-linked immunosorbent assay (ELISA). This method was proved to be highly sensitive to Der f1 compared with other airborne allergens. For the implementation of airborne allergen measurement in a residential environment, a bioaerosol sampler was constructed. The airborne allergen generated by a nebulizer was conveyed to a newly sampler we developed for collecting airborne Der f1. The sampler was composed of polymethyl methacrylate (PMMA) cells for gas/liquid phases and some porous membranes which were sandwiched in between the two phases. Der f1 in air was collected by the sampler and measured using the fiber-optic immunoassay system. The concentration of Der f1 in aerosolized standards was in the range from 0.125 to 2.0 mg/m(3) and the collection rate of the device was approximately 0.2%. © 2013 Elsevier B.V. All rights reserved.

  18. Comparison of endotoxin levels found in primary and secondary endodontic infections.

    PubMed

    Gomes, Brenda P F A; Endo, Marcos S; Martinho, Frederico C

    2012-08-01

    This clinical study was conducted to compare the levels of endotoxins (lipopolysaccharides [LPSs]) found in primary and secondary endodontic infections with apical periodontitis by correlating LPS contents with clinical/radiographic findings. In addition, the presence of target gram-negative anaerobic bacteria was also investigated. Samples were taken from 15 root canals with primary infections and 15 with secondary infections by using paper points. The limulus amebocyte lysate assay was used to quantify endotoxins, and the polymerase chain reaction technique (16S rDNA) was used for bacterial investigation. Endotoxins were detected in 100% of the root canal samples collected from primary (15/15) and secondary (15/15) infections with median values of 7.49 EU/mL and 3.96 EU/mL, respectively (P < .05). The median value of endotoxins found in the presence of clinical symptoms was significantly higher than in asymptomatic teeth with primary infections (P < .05). A positive correlation was found between endotoxin contents and a larger size of the radiolucent area (>3 mm) (P < .05). Prevotella nigrescens (10/15, 4/15), Fusobacterium nucleatum (5/15, 1/15), Treponema denticola (3/15, 1/15), and Treponema socranskii (5/15, 1/15) were detected in teeth with primary and secondary infections, respectively. P. endodontalis was present only in teeth with primary infections (5/15). Teeth with primary endodontic infections had higher contents of endotoxins and a more complex gram-negative bacterial community than teeth with secondary infections. Moreover, the levels of endotoxins were related to the severity of bone destruction in periapical tissues as well as the development of clinical features in teeth with primary infections. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. THE INFLUENCE OF ENDOTOXIN ADMINISTRATION ON THE NUTRITIONAL REQUIREMENTS OF MICE

    PubMed Central

    Dubos, René; Costello, Richard; Schaedler, Russell W.

    1965-01-01

    Albino mice lose weight within 24 hours following administration of bacterial endotoxin. The initial weight loss is proportional to the dose of endotoxin injected only when this dose is very small. The loss during the 1st day reaches a maximum with 10 to 30 µg of endotoxin; larger doses increase the duration of the overall effect. The rate at which mice regain weight after administration of endotoxin is markedly influenced by the composition of the diet. Recovery was rapid and complete within a few days when the animals were fed commercial pellets or a semisynthetic diet containing casein. In contrast, recovery was slow and incomplete when wheat gluten was used instead of casein in the diet. The deleterious effect of the gluten diet was less marked in older than in younger animals, probably because the latter have less exacting nutritional requirements. It was postulated that the failure of endotoxin-treated mice to regain weight when fed the gluten diet was due to the fact that this protein is low in certain amino acids. In fact, rapid and complete recovery from the weight loss uniformly occurred when the gluten diet was supplemented with proper amounts of lysine and threonine. The composition of the diet did not influence the extent of the initial loss of weight caused by endotoxin, nor did it prevent the animals from developing tolerance to this substance. PMID:5322368

  20. Single session of Nd:YAG laser intracanal irradiation neutralizes endotoxin in dental root dentin

    NASA Astrophysics Data System (ADS)

    Archilla, José R. F.; Moreira, Maria S. N. A.; Miyagi, Sueli P. H.; Bombana, Antônio C.; Gutknecht, Norbert; Marques, Márcia M.

    2012-11-01

    Endotoxins released in the dental root by Gram-negative microorganisms can be neutralized by calcium hydroxide, when this medication is applied inside the root canal for at least seven days. However, several clinical situations demand faster root canal decontamination. Thus, for faster endotoxin neutralization, endodontists are seeking additional treatments. The in vitro study tested whether or not intracanal Nd:YAG laser irradiation would be able to neutralize endotoxin within the human dental root canal in a single session. Twenty-four human teeth with one root were mounted between two chambers. After conventional endodontic treatment, root canals were contaminated with Escherichia coli endotoxin. Then they were irradiated or not (controls) in contact mode with an Nd:YAG laser (1.5 W, 15 Hz, 100 mJ and pulse fluency of 124 J/cm2). The endotoxin activity was measured using the limulus lysate technique and data were statistically compared (p≤0.05). The concentration of active endotoxin measured in the negative control group was significantly lower than that of the positive control group (p=0.04). The concentrations of endotoxin in both irradiated groups were significantly lower than that of the positive control group (p=0.027) and similar to that of negative control group (p=0.20). A single session of intracanal Nd:YAG laser irradiation is able to neutralize endotoxin in the dental root tissues.

  1. Single session of Nd:YAG laser intracanal irradiation neutralizes endotoxin in dental root dentin.

    PubMed

    Archilla, José R F; Moreira, Maria S N A; Miyagi, Sueli P H; Bombana, Antônio C; Gutknecht, Norbert; Marques, Márcia M

    2012-11-01

    Endotoxins released in the dental root by Gram-negative microorganisms can be neutralized by calcium hydroxide, when this medication is applied inside the root canal for at least seven days. However, several clinical situations demand faster root canal decontamination. Thus, for faster endotoxin neutralization, endodontists are seeking additional treatments. The in vitro study tested whether or not intracanal Nd:YAG laser irradiation would be able to neutralize endotoxin within the human dental root canal in a single session. Twenty-four human teeth with one root were mounted between two chambers. After conventional endodontic treatment, root canals were contaminated with Escherichia coli endotoxin. Then they were irradiated or not (controls) in contact mode with an Nd:YAG laser (1.5 W, 15 Hz, 100 mJ and pulse fluency of 124  J/cm2). The endotoxin activity was measured using the limulus lysate technique and data were statistically compared (p≤0.05). The concentration of active endotoxin measured in the negative control group was significantly lower than that of the positive control group (p=0.04). The concentrations of endotoxin in both irradiated groups were significantly lower than that of the positive control group (p=0.027) and similar to that of negative control group (p=0.20). A single session of intracanal Nd:YAG laser irradiation is able to neutralize endotoxin in the dental root tissues.

  2. Experimental design and Bayesian networks for enhancement of delta-endotoxin production by Bacillus thuringiensis.

    PubMed

    Ennouri, Karim; Ayed, Rayda Ben; Hassen, Hanen Ben; Mazzarello, Maura; Ottaviani, Ennio

    2015-12-01

    Bacillus thuringiensis (Bt) is a Gram-positive bacterium. The entomopathogenic activity of Bt is related to the existence of the crystal consisting of protoxins, also called delta-endotoxins. In order to optimize and explain the production of delta-endotoxins of Bacillus thuringiensis kurstaki, we studied seven medium components: soybean meal, starch, KH₂PO₄, K₂HPO₄, FeSO₄, MnSO₄, and MgSO₄and their relationships with the concentration of delta-endotoxins using an experimental design (Plackett-Burman design) and Bayesian networks modelling. The effects of the ingredients of the culture medium on delta-endotoxins production were estimated. The developed model showed that different medium components are important for the Bacillus thuringiensis fermentation. The most important factors influenced the production of delta-endotoxins are FeSO₄, K2HPO₄, starch and soybean meal. Indeed, it was found that soybean meal, K₂HPO₄, KH₂PO₄and starch also showed positive effect on the delta-endotoxins production. However, FeSO4 and MnSO4 expressed opposite effect. The developed model, based on Bayesian techniques, can automatically learn emerging models in data to serve in the prediction of delta-endotoxins concentrations. The constructed model in the present study implies that experimental design (Plackett-Burman design) joined with Bayesian networks method could be used for identification of effect variables on delta-endotoxins variation.

  3. Fingolimod against endotoxin-induced fetal brain injury in a rat model.

    PubMed

    Yavuz, And; Sezik, Mekin; Ozmen, Ozlem; Asci, Halil

    2017-11-01

    Fingolimod is a sphingosine-1-phosphate receptor modulator used for multiple sclerosis treatment and acts on cellular processes such as apoptosis, endothelial permeability, and inflammation. We hypothesized that fingolimod has a positive effect on alleviating preterm fetal brain injury. Sixteen pregnant rats were divided into four groups of four rats each. On gestational day 17, i.p. endotoxin was injected to induce fetal brain injury, followed by i.p. fingolimod (4 mg/kg maternal weight). Hysterotomy for preterm delivery was performed 6 h after fingolimod. The study groups included (i) vehicle controls (i.p. normal saline only); (ii) positive controls (endotoxin plus saline); (iii) saline plus fingolimod; and (iv) endotoxin plus fingolimod treatment. Brain tissues of the pups were dissected for evaluation of interleukin (IL)-6, caspase-3, and S100β on immunohistochemistry. Maternal fingolimod treatment attenuated endotoxin-related fetal brain injury and led to lower immunoreactions for IL-6, caspase-3, and S100β compared with endotoxin controls (P < 0.0001 for all comparisons). Antenatal maternal fingolimod therapy had fetal neuroprotective effects by alleviating preterm birth-related fetal brain injury with inhibitory effects on inflammation and apoptosis. © 2017 Japan Society of Obstetrics and Gynecology.

  4. Dialysate bacterial endotoxin as a prognostic indicator of peritoneal dialysis related peritonitis.

    PubMed

    Szeto, Cheuk-Chun; Lai, Ka-Bik; Chow, Kai-Ming; Kwan, Bonnie Ching-Ha; Law, Man-Ching; Pang, Wing-Fai; Ma, Terry King-Wing; Leung, Chi-Bon; Li, Philip Kam-Tao

    2016-12-01

    Peritonitis is the major complication of peritoneal dialysis (PD). The aim of our present study is to explore the prognostic value of endotoxin level in PD effluent for the prediction of treatment failure in PD-related peritonitis. We studied 325 peritonitis episodes in 223 patients. PD effluent (PDE) was collected every 5 days for endotoxin level and leukocyte count. Patients were followed for relapsing or recurrent peritonitis. We found 20 episodes (6.2%) had primary treatment failure; 41 (12.6%) developed relapsing, 19 (5.8%) had recurrent, and 22 (6.8%) had repeat episodes. Endotoxin was detectable in the PDE of 19 episodes (24.4%) caused by Gram negative organisms, 4 episodes (6.8%) of mixed bacterial growth, and none of the culture negative episodes or those by Gram positive organisms. For episodes caused by Gram negative bacteria, a detectable endotoxin level in PDE on day 5 had a sensitivity and specificity of 66.7% and 83.3%, respectively, for predicting primary treatment failure. In contrast, PDE leukocyte count > 1000 per mm3 on day 5 had a sensitivity and specificity of 88.9% and 89.1%, respectively; the addition of PDE endotoxin assay did not improve the sensitivity or specificity. We conclude that detectable endotoxin in PDE 5 days after antibiotic therapy might predict primary treatment failure in peritonitis episodes caused by Gram negative organisms. However, the sensitivity and specificity of PDE endotoxin assay was inferior to PDE leukocyte count. © 2016 Asian Pacific Society of Nephrology.

  5. Allergenic characterization of a novel allergen, homologous to chymotrypsin, from german cockroach.

    PubMed

    Jeong, Kyoung Yong; Son, Mina; Lee, Jae Hyun; Hong, Chein Soo; Park, Jung Won

    2015-05-01

    Cockroach feces are known to be rich in IgE-reactive components. Various protease allergens were identified by proteomic analysis of German cockroach fecal extract in a previous study. In this study, we characterized a novel allergen, a chymotrypsin-like serine protease. A cDNA sequence homologous to chymotrypsin was obtained by analysis of German cockroach expressed sequence tag (EST) clones. The recombinant chymotrypsins from the German cockroach and house dust mite (Der f 6) were expressed in Escherichia coli using the pEXP5NT/TOPO vector system, and their allergenicity was investigated by ELISA. The deduced amino acid sequence of German cockroach chymotrypsin showed 32.7 to 43.1% identity with mite group 3 (trypsin) and group 6 (chymotrypsin) allergens. Sera from 8 of 28 German cockroach allergy subjects (28.6%) showed IgE binding to the recombinant protein. IgE binding to the recombinant cockroach chymotrypsin was inhibited by house dust mite chymotrypsin Der f 6, while it minimally inhibited the German cockroach whole body extract. A novel allergen homologous to chymotrypsin was identified from the German cockroach and was cross-reactive with Der f 6.

  6. Evaluation of the sensitizing potential of food proteins using two mouse models.

    PubMed

    Smit, Joost; Zeeuw-Brouwer, Mary-Lène de; van Roest, Manon; de Jong, Govardus; van Bilsen, Jolanda

    2016-11-16

    The current methodology to identify allergenic food proteins is effective in identifying those that are likely to cross-react with known allergens. However, most assays show false positive results for low/non-allergens. Therefore, an ex vivo/in vitro DC-T cell assay and an in vivo mouse model were used to distinguish known allergenic food proteins (Ara h 1, β-Lactoglobulin, Pan b 1, bovine serum albumin, whey protein isolate) from low/non allergenic food proteins (soy lipoxygenase, gelatin, beef tropomyosin, rubisco, Sola t 1). CD4+ T cells from protein/alum-immunized mice were incubated with corresponding protein-pulsed bone marrow-derived DC and analyzed for cytokine release. All known allergens induced Th2 responses in vitro, whereas soy lipoxygenase, gelatin or beef tropomyosin did not. Sola t 1 and rubisco induced a more generalized T cell response due to endotoxin contamination, indicating the endotoxin-sensitivity of the DC-T assay. To analyze responses in vivo, mice were orally sensitized on days 0 and 7. Known allergens induced IgE and mMCP-1 release upon oral challenge at day 16, whereas the low/non-allergens did not. Both the DC-T cell assay and the mouse model were able to distinguish 5 known allergens from 5 low/non-allergens and may be useful to identify novel allergenic food proteins. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. [Current contact allergens].

    PubMed

    Geier, J; Uter, W; Lessmann, H; Schnuch, A

    2011-10-01

    Ever-changing exposure to contact allergens, partly due to statutory directives (e.g. nickel, chromate, methyldibromo glutaronitrile) or recommendations from industrial associations (e.g. hydroxyisohexyl 3-cyclohexene carboxaldehyde), requires on-going epidemiologic surveillance of contact allergy. In this paper, the current state with special focus in fragrances and preservatives is described on the basis of data of the Information Network of Departments of Dermatology (IVDK) of the year 2010. In 2010, 12,574 patients were patch tested in the dermatology departments belonging to the IVDK. Nickel is still the most frequent contact allergen. However the continuously improved EU nickel directive already has some beneficial effect; sensitization frequency in young women is dropping. In Germany, chromate-reduced cement has been in use now for several years, leading to a decline in chromate sensitization in brick-layers. Two fragrance mixes are part of the German baseline series; they are still relevant. The most important fragrances in these mixes still are oak moss absolute and hydroxyisohexyl 3-cyclohexene carboxaldehyde. However, in relation to these leading allergens, sensitization frequency to other fragrances contained in the mixes seems to be increasing. Among the preservatives, MCI/MI has not lost its importance as contact allergen, in contrast to MDBGN. Sources of MCI/MI sensitization obviously are increasingly found in occupational context. Methylisothiazolinone is a significant allergen in occupational settings, and less frequently in body care products.

  8. Endotoxin-Induced Endothelial Fibrosis Is Dependent on Expression of Transforming Growth Factors β1 and β2

    PubMed Central

    Echeverría, César; Montorfano, Ignacio; Tapia, Pablo; Riedel, Claudia; Cabello-Verrugio, Claudio

    2014-01-01

    During endotoxemia-induced inflammatory disease, bacterial endotoxins circulate in the bloodstream and interact with endothelial cells (ECs), inducing dysfunction of the ECs. We previously reported that endotoxins induce the conversion of ECs into activated fibroblasts. Through endotoxin-induced endothelial fibrosis, ECs change their morphology and their protein expression pattern, thereby suppressing endothelial markers and upregulating fibrotic proteins. The most commonly used fibrotic inducers are transforming growth factor β1 (TGF-β1) and TGF-β2. However, whether TGF-β1 and TGF-β2 participate in endotoxin-induced endothelial fibrosis remains unknown. We have shown that the endotoxin-induced endothelial fibrosis process is dependent on the TGF-β receptor, ALK5, and the activation of Smad3, a protein that is activated by ALK5 activation, thus suggesting that endotoxin elicits TGF-β production to mediate endotoxin-induced endothelial fibrosis. Therefore, we investigated the dependence of endotoxin-induced endothelial fibrosis on the expression of TGF-β1 and TGF-β2. Endotoxin-treated ECs induced the expression and secretion of TGF-β1 and TGF-β2. TGF-β1 and TGF-β2 downregulation inhibited the endotoxin-induced changes in the endothelial marker VE-cadherin and in the fibrotic proteins α-SMA and fibronectin. Thus, endotoxin induces the production of TGF-β1 and TGF-β2 as a mechanism to promote endotoxin-induced endothelial fibrosis. To the best of our knowledge, this is the first report showing that endotoxin induces endothelial fibrosis via TGF-β secretion, which represents an emerging source of vascular dysfunction. These findings contribute to understanding the molecular mechanism of endotoxin-induced endothelial fibrosis, which could be useful in the treatment of inflammatory diseases. PMID:24935972

  9. Endotoxin-induced endothelial fibrosis is dependent on expression of transforming growth factors β1 and β2.

    PubMed

    Echeverría, César; Montorfano, Ignacio; Tapia, Pablo; Riedel, Claudia; Cabello-Verrugio, Claudio; Simon, Felipe

    2014-09-01

    During endotoxemia-induced inflammatory disease, bacterial endotoxins circulate in the bloodstream and interact with endothelial cells (ECs), inducing dysfunction of the ECs. We previously reported that endotoxins induce the conversion of ECs into activated fibroblasts. Through endotoxin-induced endothelial fibrosis, ECs change their morphology and their protein expression pattern, thereby suppressing endothelial markers and upregulating fibrotic proteins. The most commonly used fibrotic inducers are transforming growth factor β1 (TGF-β1) and TGF-β2. However, whether TGF-β1 and TGF-β2 participate in endotoxin-induced endothelial fibrosis remains unknown. We have shown that the endotoxin-induced endothelial fibrosis process is dependent on the TGF-β receptor, ALK5, and the activation of Smad3, a protein that is activated by ALK5 activation, thus suggesting that endotoxin elicits TGF-β production to mediate endotoxin-induced endothelial fibrosis. Therefore, we investigated the dependence of endotoxin-induced endothelial fibrosis on the expression of TGF-β1 and TGF-β2. Endotoxin-treated ECs induced the expression and secretion of TGF-β1 and TGF-β2. TGF-β1 and TGF-β2 downregulation inhibited the endotoxin-induced changes in the endothelial marker VE-cadherin and in the fibrotic proteins α-SMA and fibronectin. Thus, endotoxin induces the production of TGF-β1 and TGF-β2 as a mechanism to promote endotoxin-induced endothelial fibrosis. To the best of our knowledge, this is the first report showing that endotoxin induces endothelial fibrosis via TGF-β secretion, which represents an emerging source of vascular dysfunction. These findings contribute to understanding the molecular mechanism of endotoxin-induced endothelial fibrosis, which could be useful in the treatment of inflammatory diseases. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  10. AllergenOnline: A peer-reviewed, curated allergen database to assess novel food proteins for potential cross-reactivity.

    PubMed

    Goodman, Richard E; Ebisawa, Motohiro; Ferreira, Fatima; Sampson, Hugh A; van Ree, Ronald; Vieths, Stefan; Baumert, Joseph L; Bohle, Barbara; Lalithambika, Sreedevi; Wise, John; Taylor, Steve L

    2016-05-01

    Increasingly regulators are demanding evaluation of potential allergenicity of foods prior to marketing. Primary risks are the transfer of allergens or potentially cross-reactive proteins into new foods. AllergenOnline was developed in 2005 as a peer-reviewed bioinformatics platform to evaluate risks of new dietary proteins in genetically modified organisms (GMO) and novel foods. The process used to identify suspected allergens and evaluate the evidence of allergenicity was refined between 2010 and 2015. Candidate proteins are identified from the NCBI database using keyword searches, the WHO/IUIS nomenclature database and peer reviewed publications. Criteria to classify proteins as allergens are described. Characteristics of the protein, the source and human subjects, test methods and results are evaluated by our expert panel and archived. Food, inhalant, salivary, venom, and contact allergens are included. Users access allergen sequences through links to the NCBI database and relevant references are listed online. Version 16 includes 1956 sequences from 778 taxonomic-protein groups that are accepted with evidence of allergic serum IgE-binding and/or biological activity. AllergenOnline provides a useful peer-reviewed tool for identifying the primary potential risks of allergy for GMOs and novel foods based on criteria described by the Codex Alimentarius Commission (2003). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Heat pretreatment eliminates spurious butyrylcholinesterase enhancement of endotoxin levels in the kinetic chromogenic assay.

    PubMed

    Brawner, Andrew; Hinrichs, Steven H; Larson, Marilynn A; Lockridge, Oksana

    2016-04-05

    The kinetic chromogenic endotoxin assay measures the release of p-nitroaniline from the chromogenic peptide substrate Ac-IEAR-pNA. As part of our project to purify large quantities of human butyrylcholinesterase (HuBChE), we evaluated pure HuBChE for endotoxin levels. We found that HuBChE contributed up to 90% of the yellow p-nitroaniline product in a standard endotoxin assay through the catalytic hydrolysis of Ac-IEAR-pNA with a rate constant of 0.016 min(-1) and a Km of 2.9 mM in potassium phosphate buffer pH 7.0 at 24 °C. Thus, endotoxin concentrations for native BChE are artificially high in the kinetic chromogenic assay. Destruction of HuBChE catalytic activity by boiling yields endotoxin concentrations that more accurately reflect the endotoxin concentration in purified HuBChE preparations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Identification of Sources of Endotoxin Exposure as Input for Effective Exposure Control Strategies.

    PubMed

    van Duuren-Stuurman, Birgit; Gröllers-Mulderij, Mariska; van de Runstraat, Annemieke; Duisterwinkel, Anton; Terwoert, Jeroen; Spaan, Suzanne

    2018-02-13

    Aim of the present study is to investigate the levels of endotoxins on product samples from potatoes, onions, and seeds, representing a relevant part of the agro-food industry in the Netherlands, to gather valuable insights in possibilities for exposure control measures early in the process of industrial processing of these products. Endotoxin levels on 330 products samples from companies representing the potato, onion, and seed (processing) industry (four potato-packaging companies, five potato-processing companies, five onion-packaging companies, and four seed-processing companies) were assessed using the Limulus Amboecyte Lysate (LAL) assay. As variation in growth conditions (type of soil, growth type) and product characteristics (surface roughness, dustiness, size, species) are assumed to influence the level of endotoxin on products, different types, and growth conditions were considered when collecting the samples. Additionally, waste material, rotten products, felt material (used for drying), and process water were collected. A large variation in the endotoxin levels was found on samples of potatoes, onions, and seeds (overall geometric standard deviation 17), in the range between 0.7 EU g-1 to 16400000 EU g-1. The highest geometric mean endotoxin levels were found in plant material (319600 EU g-1), followed by soil material (49100 EU g-1) and the outer side of products (9300 EU g-1), indicating that removal of plant and soil material early in the process would be an effective exposure control strategy. The high levels of endotoxins found in the limited number of samples from rotten onions indicate that these rotten onions should also be removed early in the process. Mean endotoxin levels found in waste material (only available for seed processing) is similar to the level found in soil material, although the range is much larger. On uncleaned seeds, higher endotoxin levels were found than on cleaned seeds, indicating that cleaning processes are important

  13. Further observations on mesenteric vasoconstriction, survival and the clotting defect after endotoxin administration

    PubMed Central

    Cohen, M. M.; Greenway, C. V.; Innes, I. R.; Lister, G. E.; Murthy, V. S.; Scott, G. D.

    1973-01-01

    1. The initial response after endotoxin administration (3 mg/kg) in cats involved pulmonary vasoconstriction. This was not seen when endotoxin was given by slow infusion and it could be prevented after a bolus injection of endotoxin by pretreatment of the cats with aspirin (10 mg/kg). Intense mesenteric vasoconstriction occurred in all the cats. 2. The mesenteric vasoconstriction was a specific response of the mesenteric blood vessels. At the time the mesenteric bed constricted, the renal bed dilated, the hepatic arterial bed remained unchanged and the smooth muscle of the intestinal wall relaxed. 3. Arterial blood from cats with a fully developed mesenteric vasoconstriction after endotoxin administration was perfused through a normal intestine. No immediate vasoconstriction developed but the perfused intestine constricted slowly over 60 minutes. This suggests that mesenteric constriction was not due to circulating vasoconstrictor factors or the intestinal innervation, but involved a slow local mechanism within the intestine. It could not be prevented or reversed by a variety of pharmacological agents. 4. These observations suggest that endotoxin caused a unique type of mesenteric vasoconstriction in cats by a local mechanism which took up to 60 min to develop, was sufficiently potent to reduce mesenteric flow to <30% control, and was maintained until death of the cats. Blood from these animals did not clot when placed in a glass tube. 5. The mesenteric constriction and the clotting defect could be prevented by repeated administration of aminophylline and dextran solution before and after a bolus intravenous injection of endotoxin. Arterial pressure and mesenteric flow were maintained for at least 10 h in these experiments. Inadequate treatment intensified rather than reduced the intestinal mucosal damage. 6. Cats were treated with aspirin, endotoxin and the optimal regimen for prevention of the mesenteric constriction and allowed to recover from the anaesthetic

  14. Indoor fungal diversity in primary schools may differently influence allergic sensitization and asthma in children.

    PubMed

    Cavaleiro Rufo, João; Madureira, Joana; Paciência, Inês; Aguiar, Lívia; Pereira, Cristiana; Silva, Diana; Padrão, Patrícia; Moreira, Pedro; Delgado, Luís; Annesi-Maesano, Isabella; Oliveira Fernandes, Eduardo; Teixeira, João Paulo; Moreira, André

    2017-06-01

    Childhood exposure to microbiologic agents may influence the development of allergic and respiratory diseases. Apart from home, children spend most of their time at school, which represents an environment of significant exposure to indoor air microbes. Therefore, we aimed to assess how the prevalence of allergic sensitization and asthma in schoolchildren is affected by microbiologic exposure within classrooms. Spirometry with bronchodilation, exhaled nitric oxide measurements and skin-prick tests data were retrieved from 858 children aged 8-10 years attending 71 classrooms in 20 primary schools. Air samples were collected in all classrooms using a single-stage microbiologic air impactor through agar plates. Gram-negative endotoxins were collected using flow control pumps and analysed by limulus amebocyte lysate assay. Diversity scores were established as the number of different fungal species found in each classroom. Classrooms with increased diversity scores showed a significantly lower prevalence of children with atopic sensitization, but not asthma. The risk of sensitization increased with increasing endotoxin exposure in classrooms. Similarly, significantly higher concentrations of Penicillium spp were found in classrooms with a higher number of children with atopic sensitization. Although no causal relationships could be established, exposure to higher fungal diversity was protective against allergic sensitization but this was not seen for asthma. In contrast, higher exposure to Gram-negative endotoxins and Penicillium spp in primary school's classrooms was associated with increasing odds of allergic sensitization in children. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  15. Insect (food) allergy and allergens.

    PubMed

    de Gier, Steffie; Verhoeckx, Kitty

    2018-05-03

    Insects represent an alternative for meat and fish in satisfying the increasing demand for sustainable sources of nutrition. Approximately two billion people globally consume insects. They are particularly popular in Asia, Latin America, and Africa. Most research on insect allergy has focussed on occupational or inhalation allergy. Research on insect food safety, including allergenicity, is therefore of great importance. The objective of this review is to provide an overview of cases reporting allergy following insect ingestion, studies on food allergy to insects, proteins involved in insect allergy including cross-reactive proteins, and the possibility to alter the allergenic potential of insects by food processing and digestion. Food allergy to insects has been described for silkworm, mealworm, caterpillars, Bruchus lentis, sago worm, locust, grasshopper, cicada, bee, Clanis bilineata, and the food additive carmine, which is derived from female Dactylopius coccus insects. For cockroaches, which are also edible insects, only studies on inhalation allergy have been described. Various insect allergens have been identified including tropomyosin and arginine kinase, which are both pan-allergens known for their cross-reactivity with homologous proteins in crustaceans and house dust mite. Cross-reactivity and/or co-sensitization of insect tropomyosin and arginine kinase has been demonstrated in house dust mite and seafood (e.g. prawn, shrimp) allergic patients. In addition, many other (allergenic) species (various non-edible insects, arachnids, mites, seafoods, mammals, nematoda, trematoda, plants, and fungi) have been identified with sequence alignment analysis to show potential cross-reactivity with allergens of edible insects. It was also shown that thermal processing and digestion did not eliminate insect protein allergenicity. Although purified natural allergens are scarce and yields are low, recombinant allergens from cockroach, silkworm, and Indian mealmoth are

  16. Ambient endotoxin in PM10 and association with inflammatory activity, air pollutants, and meteorology, in Chitwan, Nepal.

    PubMed

    Mahapatra, Parth Sarathi; Jain, Sumeet; Shrestha, Sujan; Senapati, Shantibhusan; Puppala, Siva Praveen

    2018-03-15

    Endotoxin associated with ambient PM (particulate matter) has been linked to adverse respiratory symptoms, but there have been few studies of ambient endotoxin and its association with co-pollutants and inflammation. Our aim was to measure endotoxin associated with ambient PM 10 (particulate matter with aerodynamic diameter<10μm) in summer 2016 at four locations in Chitwan, Nepal, and investigate its association with meteorology, co-pollutants, and inflammatory activity. PM 10 concentrations were recorded and filter paper samples were collected using E-samplers; PM 1, PM 2.5 , black carbon (BC), methane (CH 4 ), and carbon monoxide (CO) were also measured. The Limulus amebocyte lysate (LAL) assay was used for endotoxin quantification and the nuclear factor kappa B (NFκB) activation assay to assess inflammatory activity. The mean concentration of PM 10 at the different locations ranged from 136 to 189μg/m 3 , and of endotoxin from 0.29 to 0.53EU/m 3 . Pollutant presence was positively correlated with endotoxin. Apart from relative humidity, meteorological variations had no significant impact on endotoxin concentration. NF-κB activity was negatively correlated with endotoxin concentration. To the best of our knowledge, this study provides the first measurements of ambient endotoxin associated with PM 10 in Nepal. Endotoxin and co-pollutants were positively associated indicating a similar source. Endotoxin was negatively correlated with inflammatory activity as a result of a time-limited forest fire event during the sampling period. Studies of co-pollutants suggested that the higher levels of endotoxin related to biomass burning were accompanied by increased levels of anti-inflammatory agents, which suppressed the endotoxin inflammatory effect. Copyright © 2017. Published by Elsevier B.V.

  17. Evidence against a bacterial endotoxin masking effect in biologic drug products by limulus amebocyte lysate detection.

    PubMed

    Bolden, Jay S; Claerbout, Mark E; Miner, Matthew K; Murphy, Marie A; Smith, Kelly R; Warburton, Rob E

    2014-01-01

    The inability to detect endotoxin using compendia methods is a potential safety concern for patients due to the lack of endotoxin removal capabilities at the fill-finish stage in typical aseptic biologic drug product manufacturing. We have successfully demonstrated endotoxin challenge study recovery methodology using mammalian cell-produced biologic drug products and drug substances in citrate, histidine, phosphate, and sodium acetate buffer formulations containing polysorbate, challenged with an endotoxin analyte, for up to 6 months of storage. Successful recovery was similarly demonstrated for a preserved, peptide-containing drug product formulation. To isolate a potential masking-or low-endotoxin recovery-source, additional studies were performed to evaluate factors including product manufacturing contact surfaces, drug product matrix with and without polysorbate, individual matrix components, protein concentration, reagent suppliers, an orthogonal test method, and storage conditions. In all cases, acceptable recoveries were observed. Bacterial endotoxin is known to be chemically stable at physiological conditions. Purified endotoxin in aqueous conditions is likely to self-aggregate or bind to surfaces. Neither the nature of, nor the storage conditions of, the studied formulation matrices were shown experimentally to render the challenge endotoxin biologically inactive. The results highlight the importance of appropriate study design in assessing the recovery of endotoxins. Bacterial endotoxin is a Gram-negative bacterial cell wall component that is harmful to humans at threshold concentrations, and it is not expected to be in aseptically-produced pharmaceutical medicines. It has been suggested that endotoxin cannot be detected over time in certain biopharmaceutical drug product formulations containing citrate, phosphate, and polysorbate components via an unknown masking mechanism. We have generated and present data here that indicate that endotoxin can be

  18. Specific B-cell Epitope of Per a 1: A Major Allergen of American Cockroach (Periplaneta americana) and Anatomical Localization.

    PubMed

    Sookrung, Nitat; Khetsuphan, Thanyathon; Chaisri, Urai; Indrawattana, Nitaya; Reamtong, Onrapak; Chaicumpa, Wanpen; Tungtrongchitr, Anchalee

    2014-07-01

    Cockroach (CR) is a common source of indoor allergens, and Per a 1 is a major American CR (Periplaneta americana) allergen; however, several attributes of this protein remain unknown. This study identifies a novel specific B cell epitope and anatomical locations of Per a 1.0105. Recombinant Per a 1.0105 (rPer a 1.0105) was used as BALB/c mouse immunogen for the production of monoclonal antibodies (MAb). The MAb specific B cell epitope was identified by determining phage mimotopic peptides and pair-wise alignment of the peptides with the rPer a 1.0105 amino acid sequence. Locations of the Per a 1.0105 in P. americana were investigated by immunohistochemical staining. The rPer a 1.0105 (~13 kDa) had 100%, 98% and ≥90% identity to Per a 1.0105, Per a 1.0101, and Cr-PII, respectively. The B-cell epitope of the Per a 1.0105 specific-MAb was located at residues(99) QDLLLQLRDKGV(110) contained in all 5 Per a 1.01 isoforms and Per a 1.02. The epitope was analogous to the Bla g 1.02 epitope; however, this B-cell epitope was not an IgE inducer. Per a 1.0105 was found in the midgut and intestinal content of American CR but not in the other organs. The amount of the Per a 1 was ~544 ℃g per gram of feces. The novel Per a 1 B-cell epitope described in this study is a useful target for allergen quantification in samples; however, the specific MAb can be used as an allergen detection reagent. The MAb based-affinity resin can be made for allergen purification, and the so-purified protein can serve as a standard and diagnostic allergen as well as a therapeutic vaccine component. The finding that the Per a 1 is contained in the midgut and feces is useful to increase yield and purity when preparing this allergen.

  19. Specific B-cell Epitope of Per a 1: A Major Allergen of American Cockroach (Periplaneta americana) and Anatomical Localization

    PubMed Central

    Sookrung, Nitat; Khetsuphan, Thanyathon; Chaisri, Urai; Indrawattana, Nitaya; Reamtong, Onrapak; Chaicumpa, Wanpen

    2014-01-01

    Purpose Cockroach (CR) is a common source of indoor allergens, and Per a 1 is a major American CR (Periplaneta americana) allergen; however, several attributes of this protein remain unknown. This study identifies a novel specific B cell epitope and anatomical locations of Per a 1.0105. Methods Recombinant Per a 1.0105 (rPer a 1.0105) was used as BALB/c mouse immunogen for the production of monoclonal antibodies (MAb). The MAb specific B cell epitope was identified by determining phage mimotopic peptides and pair-wise alignment of the peptides with the rPer a 1.0105 amino acid sequence. Locations of the Per a 1.0105 in P. americana were investigated by immunohistochemical staining. Results The rPer a 1.0105 (~13 kDa) had 100%, 98% and ≥90% identity to Per a 1.0105, Per a 1.0101, and Cr-PII, respectively. The B-cell epitope of the Per a 1.0105 specific-MAb was located at residues99 QDLLLQLRDKGV110 contained in all 5 Per a 1.01 isoforms and Per a 1.02. The epitope was analogous to the Bla g 1.02 epitope; however, this B-cell epitope was not an IgE inducer. Per a 1.0105 was found in the midgut and intestinal content of American CR but not in the other organs. The amount of the Per a 1 was ~544 ℃g per gram of feces. Conclusions The novel Per a 1 B-cell epitope described in this study is a useful target for allergen quantification in samples; however, the specific MAb can be used as an allergen detection reagent. The MAb based-affinity resin can be made for allergen purification, and the so-purified protein can serve as a standard and diagnostic allergen as well as a therapeutic vaccine component. The finding that the Per a 1 is contained in the midgut and feces is useful to increase yield and purity when preparing this allergen. PMID:24991456

  20. Tumor necrosis factor and interleukin 1 as mediators of endotoxin-induced beneficial effects

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

    Urbaschek, R.; Urbaschek, B.

    Bacterial lipopolysaccharides or endotoxins are known to induce tumor necrosis; enhanced nonspecific resistance to bacterial, viral, and parasitic infections and to radiation sickness; and tolerance to lethal doses of endotoxin. These beneficial effects are achieved by pretreatment with minute amounts of endotoxin. Recombinant tumor necrosis factor (TNF) and interleukin 1 (IL-1) are among the mediators capable of invoking radioprotection or resistance to the consequences of cecal ligation and puncture. Both cytokines are potent inducers of serum colony-stimulating factor (CSF) in C3H/HeJ mice (low responders to endotoxin). The number of splenic granulocyte-macrophage precursors was found to increase 5 days after injectionmore » of TNF in these mice. Although with IL-1 no increase in the number of granulocyte-macrophage colonies occurred in culture in the presence of serum CSF, a marked stimulation was observed when TNF was added. This stimulation of myelopoiesis observed in vivo and in vitro may be related to the radioprotective effect of TNF. The data presented suggest that TNF and IL-1 released after injection of endotoxin participate in the mediation of endotoxin-induced enhancement of nonspecific resistance and stimulation of hematopoiesis. 76 references.« less

  1. The role of amoebocytes in endotoxin-mediated coagulation in the innate immunity of Achatina fulica snails.

    PubMed

    Biswas, C; Mandal, C

    1999-02-01

    Achatina amoebocyte lysate (AAL) derived from amoebocytes of Achatina fulica was activated by Gram-negative bacterial endotoxins in a time-dependent manner resulting in gel formation/coagulation. The activation and maximum proliferation of amoebocytes was observed 40 min after intramuscular injection (20 microg/snail) of endotoxin. Endotoxin-mediated proteolytic activity of AAL towards a serine-protease-specific chromogenic substrate was maximum at pH 8.0, 37 degrees C and within 15 min in a divalent-cation-dependent manner. The AAL activity induced by the endotoxin was directly dependent on the endotoxin concentration, showed a high specificity and saturated at higher endotoxin concentrations. An endotoxin-sensitive factor (ESF) was purified from AAL to apparent homogeneity by single-step affinity chromatography on a heparin-Sepharose 4B column. Native ESF of molecular weight 140 000 was composed of two identical subunits of molecular weight 70 000 attached through non-covalent association. A strong binding to endotoxin (Escherichia coli 055:B5) was exhibited by ESF with a 40-fold higher biological activity than AAL. The ESF was shown to have a unique Phe-Ile active site with regard to its alternate activation by alpha-chymotrypsin instead of endotoxin. The ESF was characterized as a serine protease type as evidenced by potent inhibition with specific inhibitors.

  2. Electrostatic dust collectors compared to inhalable samplers for measuring endotoxin concentrations in farm homes

    PubMed Central

    Kilburg-Basnyat, Brita; Peters, Thomas M.; Perry, Sarah S.; Thorne, Peter S.

    2016-01-01

    Paired electrostatic dust collectors (EDCs) and daily, inhalable button samplers (BS) were used concurrently to sample endotoxin in 10 farm homes during 7-day periods in summer and winter. Winter sampling included an optical particle counter (OPC) to measure PM2.5 and PM2.5-10. Electrostatic dust collectors and BS filters were analyzed for endotoxin using the kinetic chromogenic Limulus amebocyte lysate assay. Optical particle counter particulate matter (PM) data were divided into two PM categories. In summer, geometric mean (geometric standard deviation) endotoxin concentrations were 0.82 EU/m3 (2.7) measured with the BS and 737 EU/m2 (1.9) measured with the EDC. Winter values were 0.52 EU/m3 (3.1) for BS and 538 EU/m2 (3.0) for EDCs. Seven day endotoxin values of EDCs were highly correlated with the 7-day BS sampling averages (r=0.70; p<0.001). Analysis of variance indicated a 2.4-fold increase in EDC endotoxin concentrations for each unit increase of the ratio of PM2.5 to PM2.5-10. There was also a significant correlation between BS and EDCs endotoxin concentrations for winter (r=0.67; p<0.05) and summer(r=0.75; p<0.05). Thus, EDCs sample comparable endotoxin concentrations to BS, making EDCs a feasible, easy to use alternative to BS for endotoxin sampling. PMID:26296624

  3. Comparison of allergenicity and immunogenicity of an intact allergen vaccine and commercially available allergoid products for birch pollen immunotherapy.

    PubMed

    Lund, L; Henmar, H; Würtzen, P A; Lund, G; Hjortskov, N; Larsen, J N

    2007-04-01

    Specific immunotherapy with intact allergen vaccine is a well-documented treatment for allergic diseases. Different vaccine formulations are currently commercially available, the active ingredient either being intact allergens or chemically modified allergoids. The rationale behind allergoids is to decrease allergenicity while maintaining immunogenicity. However, data from the German health authorities based on reporting of adverse events over a 10-year period did not indicate increased safety of allergoids over intact allergens. The objective of this study was to investigate the effect of chemical modification on allergenicity and immunogenicity comparing four commercial allergoid products for birch pollen immunotherapy with an intact allergen vaccine. Solid-phase IgE inhibition and histamine release assays were selected as model systems for allergenicity, and a combination of human T cell proliferation and IgG titres following mouse immunizations were used to address the immunogenicity of the intact allergen vaccine and the four allergoids. In all assays, the products were normalized with respect to the manufacturer's recommended maintenance dose. IgE inhibition experiments showed a change in epitope composition comparing intact allergen vaccine with allergoid. One allergoid product induced enhanced histamine release compared to the intact allergens, while the other three allergoids showed reduced release. Standard T cell stimulation assays using lines from allergic patients showed a reduced response for all allergoids compared with the intact allergen vaccine regardless of the cell type used for antigen presentation. All allergoids showed reduced capacity to induce allergen-specific IgG responses in mice. While some allergoids were associated with reduced allergenicity, a clear reduction in immunogenicity was observed for all allergoid products compared with the intact allergen vaccine, and the commercial allergoids tested therefore do not fulfil the allergoid

  4. Endotoxin-induced mortality in rats is reduced by nitrones

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

    Hamburger, S.A.; McCay, P.B.

    The goal of these investigations was to determine if nitrone spin-trapping agents can alter mortality associated with endotoxemia in the rat. Reactive free radicals attack nitrone spin-trapping agents forming relatively reactive, persistent free radical spin adducts. We administered 85 mM (10 ml/kg) of alpha-phenyl N-tert-butyl nitrone (PBN), alpha-4-pyridyl-N-oxide N-tert-butyl nitrone (4-POBN), 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), or vehicle (saline i.p.) 30 min before endotoxin (25 mg/kg i.p.) or vehicle to Sprague-Dawley (SD) or Holtzman virus-free (HVF) rats (n = 10-17/group). All vehicle-treated rats receiving endotoxin were dead by 1 day. At 7 days, 83% of PBN-treated SD, 42% of PBN- or POBN-treated HVF,more » and 25% of DMPO-treated HVF rats were alive. The difference in survival of PBN-treated animals between strains may reflect the higher susceptibility of HVF rats to endotoxin. The observed reduction in mortality may be related to the well-established capacity of spin-trapping agents to capture reactive free radicals that may be generated in target tissues in response to endotoxin, and that would otherwise react with cell components and produce tissue injury.« less

  5. Identification of major allergens in watermelon.

    PubMed

    Pastor, Carlos; Cuesta-Herranz, Javier; Cases, Barbara; Pérez-Gordo, Marina; Figueredo, Elena; de las Heras, Manuel; Vivanco, Fernando

    2009-01-01

    Watermelon is a worldwide consumed Cucurbitaceae fruit that can elicit allergic reactions. However, the major allergens of watermelon are not known. The aim of this study is to identify and characterize major allergens in watermelon. Twenty-three patients allergic to watermelon took part in the study. The diagnosis was based on a history of symptoms and positive skin prick-prick tests to watermelon, confirmed by positive open oral challenge testing to watermelon pulp. Allergenic components were detected by SDS-PAGE and immunoblotting. Molecular characterization of IgE-binding bands was performed by N-terminal amino acid sequencing and mass spectrometry. Allergens were purified combining several chromatographic steps. Several IgE binding bands (8-120 kDa) were detected in watermelon extract. Three major allergens were identified as malate dehydrogenase (36 kDa), triose phosphate isomerase (28 kDa) and profilin (13 kDa). Purified allergens individually inhibited IgE binding to the whole watermelon extract. All in all these results indicate that malate dehydrogenase, triose phosphate isomerase and profilin are major allergens involved in watermelon allergy. Copyright (C) 2009 S. Karger AG, Basel.

  6. The processing and collaborative assay of a reference endotoxin.

    PubMed

    Hochstein, H D; Mills, D F; Outschoorn, A S; Rastogi, S C

    1983-10-01

    A preparation of Escherichia coli bacterial endotoxin, the latest of successive lots drawn from bulk material which has been studied in laboratory tests and in animals and humans for suitability as a reference endotoxin, has been filled and lyophilized in a large number of vials. Details of its characterization, including stability studies, are given. A collaborative assay was conducted by 14 laboratories using gelation end-points with Limulus amebocyte lysates. Approximate continuity of the unit of potency with the existing national unit was achieved. The lot was made from the single final bulk but had to be freeze-dried in five sublimators. An assessment was therefore made for possible heterogeneity. The results indicate that the lot can be used as a large homogeneous quantity. The advantages of using it widely as a standard for endotoxins are discussed.

  7. Medical diagnostics for indoor mold exposure.

    PubMed

    Hurraß, Julia; Heinzow, Birger; Aurbach, Ute; Bergmann, Karl-Christian; Bufe, Albrecht; Buzina, Walter; Cornely, Oliver A; Engelhart, Steffen; Fischer, Guido; Gabrio, Thomas; Heinz, Werner; Herr, Caroline E W; Kleine-Tebbe, Jörg; Klimek, Ludger; Köberle, Martin; Lichtnecker, Herbert; Lob-Corzilius, Thomas; Merget, Rolf; Mülleneisen, Norbert; Nowak, Dennis; Rabe, Uta; Raulf, Monika; Seidl, Hans Peter; Steiß, Jens-Oliver; Szewszyk, Regine; Thomas, Peter; Valtanen, Kerttu; Wiesmüller, Gerhard A

    2017-04-01

    In April 2016, the German Society of Hygiene, Environmental Medicine and Preventative Medicine (Gesellschaft für Hygiene, Umweltmedizin und Präventivmedizin (GHUP)) together with other scientific medical societies, German and Austrian medical societies, physician unions and experts has provided an AWMF (Association of the Scientific Medical Societies) guideline 'Medical diagnostics for indoor mold exposure'. This guideline shall help physicians to advise and treat patients exposed indoors to mold. Indoor mold growth is a potential health risk, even without a quantitative and/or causal association between the occurrence of individual mold species and health effects. Apart from the allergic bronchopulmonary aspergillosis (ABPA) and the mycoses caused by mold, there is only sufficient evidence for the following associations between moisture/mold damages and different health effects: Allergic respiratory diseases, asthma (manifestation, progression, exacerbation), allergic rhinitis, exogenous allergic alveolitis and respiratory tract infections/bronchitis. In comparison to other environmental allergens, the sensitizing potential of molds is estimated to be low. Recent studies show a prevalence of sensitization of 3-10% in the total population of Europe. The evidence for associations to mucous membrane irritation and atopic eczema (manifestation, progression, exacerbation) is classified as limited or suspected. Inadequate or insufficient evidence for an association is given for COPD, acute idiopathic pulmonary hemorrhage in children, rheumatism/arthritis, sarcoidosis, and cancer. The risk of infections from indoor molds is low for healthy individuals. Only molds that are capable to form toxins can cause intoxications. The environmental and growth conditions and especially the substrate determine whether toxin formation occurs, but indoor air concentrations are always very low. In the case of indoor moisture/mold damages, everyone can be affected by odor effects and

  8. Treatment Characteristics of Polysaccharides and Endotoxin Using Oxygen Plasma Produced by RF Discharge

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

    Kitazaki, Satoshi; Hayashi, Nobuya; Goto, Masaaki

    Treatment of polysaccharides and endotoxin were attempted using oxygen plasma produced by RF discharge. Oxygen radicals observed by optical light emission spectra are factors of decomposition of polysaccharides and endotoxin. Fourier transform infrared spectra indicate that most of chemical bonds in the polysaccharides are dissociated after irradiation of the oxygen plasma. Also, the decomposition rate of endotoxin was approximately 90% after irradiation of the oxygen plasma for 180 min.

  9. Treatment Characteristics of Polysaccharides and Endotoxin Using Oxygen Plasma Produced by RF Discharge

    NASA Astrophysics Data System (ADS)

    Kitazaki, Satoshi; Hayashi, Nobuya; Goto, Masaaki

    2010-10-01

    Treatment of polysaccharides and endotoxin were attempted using oxygen plasma produced by RF discharge. Oxygen radicals observed by optical light emission spectra are factors of decomposition of polysaccharides and endotoxin. Fourier transform infrared spectra indicate that most of chemical bonds in the polysaccharides are dissociated after irradiation of the oxygen plasma. Also, the decomposition rate of endotoxin was approximately 90% after irradiation of the oxygen plasma for 180 min.

  10. Safety of engineered allergen-specific immunotherapy vaccines

    PubMed Central

    Focke-Tejkl, Margarete; Valenta, Rudolf

    2015-01-01

    Purpose of review The purpose of the review is to summarize and comment on recent developments regarding the safety of engineered immunotherapy vaccines. Recent findings In the last 2 years, several studies were published in which allergy vaccines were developed on the basis of chemical modification of natural allergen extracts, the engineering of allergen molecules by recombinant DNA technology and synthetic peptide chemistry, allergen genes, new application routes and conjugation with immune modulatory molecules. Several studies exemplified the general applicability of hypoallergenic vaccines on the basis of recombinant fusion proteins consisting of nonallergenic allergen-derived peptides fused to allergen-unrelated carrier molecules. These vaccines are engineered to reduce both, immunoglobulin E (IgE) as well as allergen-specific T cell epitopes in the vaccines, and thus should provoke less IgE and T-cell-mediated side-effects. They are made to induce allergen-specific IgG antibodies against the IgE-binding sites of allergens with the T-cell help of the carrier molecule. Summary Several interesting examples of allergy vaccines with potentially increased safety profiles have been published. The concept of fusion proteins consisting of allergen-derived hypoallergenic peptides fused to allergen-unrelated proteins that seems to be broadly applicable for a variety of allergens appears to be of particular interest because it promises not only to reduce side-effects but also to increase efficacy and convenience of allergy vaccines. PMID:22885888

  11. School exposure and asthma.

    PubMed

    Esty, Brittany; Phipatanakul, Wanda

    2018-05-01

    To provide a comprehensive overview of common school exposures and the association between school exposures and pediatric asthma morbidity. A comprehensive literature review was performed using PubMed. Full-length, peer-reviewed studies published in English were considered for review. In vivo, in vitro, and animal studies were excluded. Studies of school exposure to cockroach, mouse, dust mite, dog, cat, molds, pollution, and endotoxin associated with asthma and asthma morbidity were considered. The current literature establishes an association between school exposure and pediatric asthma morbidity. There is a need for ongoing research to evaluate the effects of school-based environmental interventions on asthma morbidity. It is evident that the indoor school environment is a significant reservoir of allergens, molds, pollutants, and endotoxin and that there is an association between school exposure and pediatric asthma morbidity. School-based interventions have the potential for substantial individual, community, and public health benefit. It is important that researchers continue to study the health effects associated with school exposures and assess cost-effectiveness of multifaceted school-based interventions. Copyright © 2018 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  12. Association of plasma endotoxin, inflammatory cytokines and risk of colorectal adenomas

    PubMed Central

    2013-01-01

    Background Recent studies suggest that bacterial endotoxins may be associated with various chronic diseases, including colorectal adenomas and cancer. Given the evidence linking inflammation and colorectal cancer, we sought to determine if plasma endotoxin concentrations are associated with indicators of systemic or local inflammation and colorectal adenomas. Methods This cross-sectional study consisted of participants who underwent screening colonoscopies and included adenoma cases (n=138) and non-adenoma controls (n=324). Plasma concentrations of endotoxin were measured with Limulus Amebocyte Lysate (LAL) assay. We quantified concentrations of inflammatory cytokines, interleukin-4 (IL-4), IL-6, IL-8, IL-10, IL-12, tumor necrosis factor-alpha (TNF-α), and interferon-γ (IFN-γ) in plasma by ELISA and mRNA expression levels in rectal mucosal biopsies by quantitative RT-PCR. Interleukin-17 was evaluated only in the rectal mucosa. Results Compared to subjects with low plasma endotoxin concentrations, those with higher concentrations were more likely to have adenomas (OR 1.4, 95% CI 1.0-2.1). Among subjects with adenomas, those with villous histology were more likely to have higher endotoxin concentrations (5.4 vs. 4.1EU/mL, p=0.05) and lower plasma IFN-γ (0 vs. 1.64 pg/mL, p=0.02) compared to those with only tubular adenomas. Cases showed a trend of having higher plasma TNF-α levels than controls (p=0.06), but none of the other plasma or rectal mucosal cytokine levels differed between cases and controls. Elevated mucosal IL-12 levels were associated with having multiple adenomas (p=0.04). Higher concentrations of plasma endotoxin predicted increased plasma IL-12 levels (OR 1.5, 95% CI 1.0-2.2) and rectal mucosal IL-12 (OR 1.9, 95% CI 1.0-3.7) and IL-17 gene expression (OR 2.2, 95% CI 1.0-4.6). Conclusions These findings suggest that interactions between elevated plasma endotoxin concentrations and inflammatory cytokines may be relevant to the development of

  13. Electrostatic dust collectors compared to inhalable samplers for measuring endotoxin concentrations in farm homes.

    PubMed

    Kilburg-Basnyat, B; Peters, T M; Perry, S S; Thorne, P S

    2016-10-01

    Paired electrostatic dust collectors (EDCs) and daily, inhalable button samplers (BS) were used concurrently to sample endotoxin in 10 farm homes during 7-day periods in summer and winter. Winter sampling included an optical particle counter (OPC) to measure PM2.5 and PM2.5-10 . Electrostatic dust collectors and BS filters were analyzed for endotoxin using the kinetic chromogenic Limulus amebocyte lysate assay. Optical particle counter particulate matter (PM) data were divided into two PM categories. In summer, geometric mean (geometric standard deviation) endotoxin concentrations were 0.82 EU/m(3) (2.7) measured with the BS and 737 EU/m(2) (1.9) measured with the EDC. Winter values were 0.52 EU/m(3) (3.1) for BS and 538 EU/m(2) (3.0) for EDCs. Seven-day endotoxin values of EDCs were highly correlated with the 7-day BS sampling averages (r = 0.70; P < 0.001). Analysis of variance indicated a 2.4-fold increase in EDC endotoxin concentrations for each unit increase of the ratio of PM2.5 to PM2.5-10 . There was also a significant correlation between BS and EDCs endotoxin concentrations for winter (r = 0.67; P < 0.05) and summer (r = 0.75; P < 0.05). Thus, EDCs sample comparable endotoxin concentrations to BS, making EDCs a feasible, easy to use alternative to BS for endotoxin sampling. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Identification of novel allergen in edible insect, Gryllus bimaculatus and its cross-reactivity with Macrobrachium spp. allergens.

    PubMed

    Srinroch, Chutima; Srisomsap, Chantragan; Chokchaichamnankit, Daranee; Punyarit, Phaibul; Phiriyangkul, Pharima

    2015-10-01

    Edible insects have recently been promoted as a source of protein and have a high nutrition value. Identification of allergens and cross-reactivity between Macrobrachium spp. and the field cricket (Gryllus bimaculatus) is necessary for food safety control and to assist in the diagnosis and therapy of allergy symptoms. Denaturing polyacrylamide gel electrophoresis (SDS-PAGE) was used to separate proteins. Allergens were determined and identified by IgE-immunoblotting with pooled sera from prawn-allergic patients (n=16) and LC-MS/MS. Arginine kinase (AK) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) were determined as the important allergens in muscle of Macrobrachium rosenbergii whereas, hemocyanin (HC) was identified as an allergen in Macrobrachium spp. The allergens in Macrobrachium lanchesteri were identified as AK and HC. In addition, hexamerin1B (HEX1B) was identified as a novel and specific allergen in G. bimaculatus. The important allergen in G. bimaculatus and Macrobrachium spp. is AK and was found to cross-react between both species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of...

  16. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of...

  17. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of...

  18. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of...

  19. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of...

  20. Relations of exhaled nitric oxide and FEV1 to personal endotoxin exposure in schoolchildren with asthma.

    PubMed

    Delfino, Ralph J; Staimer, Norbert; Tjoa, Thomas; Gillen, Daniel L

    2015-12-01

    Asthma prevalence and acute exacerbations have been associated with endotoxin exposure. However, there are limited data on relations between acute asthma outcomes in children and personal exposure to endotoxin or whether this relation is modified by personal air pollution exposures. We made repeated measurements of the fractional concentration of exhaled NO (FeNO), forced expiratory volume in 1 s (FEV1) and personal endotoxin exposures in patients with persistent asthma aged 9-18 years, each of whom was followed for 10 consecutive days in Riverside and Whittier, California. Endotoxin was measured in PM2.5, and simultaneously we measured personal exposure to air pollutants: NO2 and PM2.5 mass, elemental carbon and organic carbon. Endotoxin exposure-response relations and interactions between endotoxin and air pollutants were analysed with mixed models controlling for personal temperature, humidity and the 10-day period. Neither percent-predicted FEV1 nor FeNO was associated with personal endotoxin overall; however, endotoxin was associated with FEV1 among patients with average percent-predicted FEV1<80%. When NO2 was above its median, FeNO increased by 2.2% (95% CI -0.8% to 5.2%) for an interquartile increase in personal endotoxin, whereas FeNO was lower by -1.8% (95% CI -4% to 0.5%) when NO2 was≤its median. However, this is out of 12 interaction tests between personal endotoxin and a binary air pollutant for each outcome (FEV1 and FeNO), and there were no interactions with any continuous-scaled pollutant. Personal endotoxin exposure was not associated with acute daily changes in FeNO or FEV1 in a cohort panel of schoolchildren with asthma, except for decreased FEV1 among patients with more severe asthma (percent-predicted FEV1<80%). There was limited evidence of effect modification of endotoxin by personal exposure to air pollution. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to

  1. Endotoxin removal by radio frequency gas plasma (glow discharge)

    NASA Astrophysics Data System (ADS)

    Poon, Angela

    2011-12-01

    Contaminants remaining on implantable medical devices, even following sterilization, include dangerous fever-causing residues of the outer lipopolysaccharide-rich membranes of Gram-negative bacteria such as the common gut microorganism E. coli. The conventional method for endotoxin removal is by Food & Drug Administration (FDA)-recommended dry-heat depyrogenation at 250°C for at least 45 minutes, an excessively time-consuming high-temperature technique not suitable for low-melting or heat-distortable biomaterials. This investigation evaluated the mechanism by which E. coli endotoxin contamination can be eliminated from surfaces during ambient temperature single 3-minute to cumulative 15-minute exposures to radio-frequency glow discharge (RFGD)-generated residual room air plasmas activated at 0.1-0.2 torr in a 35MHz electrodeless chamber. The main analytical technique for retained pyrogenic bio-activity was the Kinetic Chromogenic Limulus Amebocyte Lysate (LAL) Assay, sufficiently sensitive to document compliance with FDA-required Endotoxin Unit (EU) titers less than 20 EU per medical device by optical detection of enzymatic color development corresponding to < 0.5 EU/ml in sterile water extracts of each device. The main analytical technique for identification of chemical compositions, amounts, and changes during sequential reference Endotoxin additions and subsequent RFGD-treatment removals from infrared (IR)-transparent germanium (Ge) prisms was Multiple Attenuated Internal Reflection (MAIR) infrared spectroscopy sensitive to even monolayer amounts of retained bio-contaminant. KimaxRTM 60 mm x 15 mm and 50mm x 15mm laboratory glass dishes and germanium internal reflection prisms were inoculated with E. coli bacterial endotoxin water suspensions at increments of 0.005, 0.05, 0.5, and 5 EU, and characterized by MAIR-IR spectroscopy of the dried residues on the Ge prisms and LAL Assay of sterile water extracts from both glass and Ge specimens. The Ge prism MAIR

  2. Multiple independent IgE epitopes on the highly allergenic grass pollen allergen Phl p 5.

    PubMed

    Levin, M; Rotthus, S; Wendel, S; Najafi, N; Källström, E; Focke-Tejkl, M; Valenta, R; Flicker, S; Ohlin, M

    2014-11-01

    Group 5 allergens are small proteins that consist of two domains. They belong to the most potent respiratory allergens. To determine the binding sites and to study allergic patients' IgE recognition of the group 5 allergen (Phl p 5) from timothy grass pollen using human monoclonal IgE antibodies that have been isolated from grass pollen allergic patients. Using recombinant isoallergens, fragments, mutants and synthetic peptides of Phl p 5, as well as peptide-specific antibodies, the interaction of recombinant human monoclonal IgE and Phl p 5 was studied using direct binding and blocking assays. Cross-reactivity of monoclonal IgE with group 5 allergens in several grasses was studied and inhibition experiments with patients' polyclonal IgE were performed. Monoclonal human IgE showed extensive cross-reactivity with group 5 allergens in several grasses. Despite its small size of 29 kDa, four independent epitope clusters on isoallergen Phl p 5.0101, two in each domain, were recognized by human IgE. Isoallergen Phl p 5.0201 carried two of these epitopes. Inhibition studies with allergic patients' polyclonal IgE suggest the presence of additional IgE epitopes on Phl p 5. Our results reveal the presence of a large number of independent IgE epitopes on the Phl p 5 allergen explaining the high allergenic activity of this protein and its ability to induce severe allergic symptoms. High-density IgE recognition may be a general feature of many potent allergens and form a basis for the development of improved diagnostic and therapeutic procedures in allergic disease. © 2014 The Authors. Clinical & Experimental Allergy Published by John Wiley & Sons Ltd.

  3. Multiple independent IgE epitopes on the highly allergenic grass pollen allergen Phl p 5

    PubMed Central

    Levin, M; Rotthus, S; Wendel, S; Najafi, N; Källström, E; Focke-Tejkl, M; Valenta, R; Flicker, S; Ohlin, M

    2014-01-01

    Background Group 5 allergens are small proteins that consist of two domains. They belong to the most potent respiratory allergens. Objective To determine the binding sites and to study allergic patients' IgE recognition of the group 5 allergen (Phl p 5) from timothy grass pollen using human monoclonal IgE antibodies that have been isolated from grass pollen allergic patients. Methods Using recombinant isoallergens, fragments, mutants and synthetic peptides of Phl p 5, as well as peptide-specific antibodies, the interaction of recombinant human monoclonal IgE and Phl p 5 was studied using direct binding and blocking assays. Cross-reactivity of monoclonal IgE with group 5 allergens in several grasses was studied and inhibition experiments with patients' polyclonal IgE were performed. Results Monoclonal human IgE showed extensive cross-reactivity with group 5 allergens in several grasses. Despite its small size of 29 kDa, four independent epitope clusters on isoallergen Phl p 5.0101, two in each domain, were recognized by human IgE. Isoallergen Phl p 5.0201 carried two of these epitopes. Inhibition studies with allergic patients' polyclonal IgE suggest the presence of additional IgE epitopes on Phl p 5. Conclusions & Clinical Relevance Our results reveal the presence of a large number of independent IgE epitopes on the Phl p 5 allergen explaining the high allergenic activity of this protein and its ability to induce severe allergic symptoms. High-density IgE recognition may be a general feature of many potent allergens and form a basis for the development of improved diagnostic and therapeutic procedures in allergic disease. PMID:25262820

  4. 8 Allergenic Composition of Polymerized Allergen Extracts of Betula verrucosa, Dermatophagoides Pteronyssinus and Phleum Pratense

    PubMed Central

    Fernandez-Caldas, Enrique; Cases, Barbara; Tudela, Jose Ignacio; Fernandez, Eva Abel; Casanovas, Miguel; Subiza, Jose Luis

    2012-01-01

    Background Allergoids have been successfully used in the treatment of respiratory allergic diseases. They are modified allergen extracts that allow the administration of high allergen doses, due to their reduced IgE binding capacity.They maintain allergen-specific T-cell recognition. Since they are native allergen extracts that have been polymerized with glutaraldehyde, identification of the allergenic molecules requires more complicated methods. The aim of the study was to determine the qualitative composition of different polymerized extracts and investigate the presence of defined allergenic molecules using Mass spectrometry. Methods Proteomic analysis was carried out at the Proteomics Facility of the Hospital Nacional de Parapléjicos (Toledo, Spain). After reduction and alkylation, proteins were digested with trypsin and the resulting peptides were cleaned using C18 SpinTips Sample Prep Kit; peptides were separated on an Ultimate nano-LC system using a Monolithic C18 column in combination with a precolumn for salt removal. Fractionation of the peptides was performed with a Probot microfraction collector and MS and MS/MS analysis of offline spotted peptide samples were performed using the Applied Biosystems 4800 plus MALDI TOF/TOF Analyzer mass spectrometer. ProteinPilot Software V 2.0.1 and the Paragon algorithm were used for the identification of the proteins. Each MS/MS spectrum was searched against the SwissProt 2010_10 database, Uniprot-Viridiplantae database and Uniprot_Betula database. Results Analysis of the peptides revealed the presence of native allergens in the polymerized extracts: Der p 1, Der p 2, Der p 3, Der p 8 and Der p 11 in D. pteronyssinus; Bet v 2, Bet v 6, Bet v 7 and several Bet v 1 isoforms in B. verrucosa and Phl p 1, Phl p 3, Phl p 5, Phl p 11 and Phl p 12 in P. pratense allergoids. In all cases, potential allergenic proteins were also identified, including ubiquitin, actin, Eenolase, fructose-bisphosphate aldolase, luminal

  5. Allergen concentration in natural rubber latex.

    PubMed

    Yeang, H-Y; Hamilton, R G; Bernstein, D I; Arif, S A M; Chow, K-S; Loke, Y-H; Raulf-Heimsoth, M; Wagner, S; Breiteneder, H; Biagini, R E

    2006-08-01

    Hevea brasiliensis latex serum is commonly used as the in vivo and in vitro reference antigen for latex allergy diagnosis as it contains the full complement of latex allergens. This study quantifies the concentrations of the significant allergens in latex serum and examines its suitability as an antigen source in latex allergy diagnosis and immunotherapy. The serum phase was extracted from centrifuged latex that was repeatedly freeze-thawed or glycerinated. Quantitation of latex allergens was performed by two-site immunoenzymetric assays. The abundance of RNA transcripts of the latex allergens was estimated from the number of their clones in an Expressed Sequence Tags library. The latex allergens, Hev b 1, 2, 3, 4, 5, 6, 7 and 13, were detected in freeze-thawed and glycerinated latex serum at levels ranging from 75 (Hev b 6) to 0.06 nmol/mg total proteins (Hev b 4). Hev b 6 content in the latex was up to a thousand times higher than the other seven latex allergens, depending on source and/or preparation procedure. Allergen concentration was reflected in the abundance of mRNA transcripts. When used as the antigen, latex serum may bias the outcome of latex allergy diagnostic tests towards sensitization to Hev b 6. Tests that make use of latex serum may fail to detect latex-specific IgE reactivity in subjects who are sensitized only to allergens that are present at low concentrations. Latex allergy diagnostics and immunotherapy that use whole latex serum as the antigen source may not be optimal because of the marked imbalance of its constituent allergens.

  6. Vaccine development for allergen-specific immunotherapy based on recombinant allergens and synthetic allergen peptides: Lessons from the past and novel mechanisms of action for the future

    PubMed Central

    Valenta, Rudolf; Campana, Raffaela; Focke-Tejkl, Margit; Niederberger, Verena

    2016-01-01

    In the past, the development of more effective, safe, convenient, broadly applicable, and easy to manufacture vaccines for allergen-specific immunotherapy (AIT) has been limited by the poor quality of natural allergen extracts. Progress made in the field of molecular allergen characterization has now made it possible to produce defined vaccines for AIT and eventually for preventive allergy vaccination based on recombinant DNA technology and synthetic peptide chemistry. Here we review the characteristics of recombinant and synthetic allergy vaccines that have reached clinical evaluation and discuss how molecular vaccine approaches can make AIT more safe and effective and thus more convenient. Furthermore, we discuss how new technologies can facilitate the reproducible manufacturing of vaccines of pharmaceutical grade for inhalant, food, and venom allergens. Allergy vaccines in clinical trials based on recombinant allergens, recombinant allergen derivatives, and synthetic peptides allow us to target selectively different immune mechanisms, and certain of those show features that might make them applicable not only for therapeutic but also for prophylactic vaccination. PMID:26853127

  7. Effects of daily food processing on allergenicity.

    PubMed

    Cabanillas, Beatriz; Novak, Natalija

    2017-08-11

    Daily food processing has the potential to alter the allergenicity of foods due to modification of the physico-chemical properties of proteins. The degree of such modifications depends on factors such as processing conditions, type of food considered, allergenic content, etc. The impact of daily food processing like boiling, roasting, frying or baking on food allergenicity have been extensively studied. The influence of other thermal treatments such as microwave heating or pressure cooking on allergenicity has also been analyzed. Non-thermal treatment such as peeling impacts on the allergenic content of certain foods such as fruits. In this review, we give an updated overview of the effects of daily processing treatments on the allergenicity of a wide variety of foods. The different variables that contribute to the modification of food allergenicity due to processing are also reviewed and discussed.

  8. The effect of endotoxin on heart rate dynamics in diabetic rats.

    PubMed

    Meamar, Morvarid; Dehpour, Tara; Mazloom, Roham; Sharifi, Fatemeh; Raoufy, Mohammad R; Dehpour, Ahmad R; Mani, Ali R

    2015-05-01

    The effect of endotoxin on heart rate variability (HRV) was assessed in diabetic and controls rats using a telemetric system. Endotoxin induced a reduction in sample entropy of cardiac rhythm in control animals. However, this effect was significantly blunted in streptozotocin-induced diabetic rats. Since uncoupling of cardiac pacemaker from cholinergic control is linked to reduced HRV in endotoxemia, chronotropic responsiveness to cholinergic stimulation was assessed in isolated atria. Endotoxemia was associated with impaired responsiveness to carbacholine in control rats. However, endotoxemia did not impair cholinergic responsiveness in diabetic atria. These findings corroborates with development of endotoxin tolerance in diabetic rats. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. The quest for bacterial allergens.

    PubMed

    Nordengrün, Maria; Michalik, Stephan; Völker, Uwe; Bröker, Barbara M; Gómez-Gascón, Lidia

    2018-04-26

    Allergies are complex diseases featuring local tissue inflammation, which is characterized by an exaggerated type 2 immune response to environmental compounds known as allergens. Pollens, environmental fungi, and house dust mites are examples of common allergens. Bacteria have a dual role in allergy. Usually, they are associated with protection, however, certain bacterial species promote the development and exacerbation of allergic inflammation. Notably, IgE antibodies specific for bacterial antigens are found in the sera of allergic individuals. This implies that some bacterial factors are allergens, eliciting a specific type 2 immune response. However, to date, only a few of these are molecularly defined. This review summarizes the current knowledge about known bacterial allergens, and it provides an overview of the available techniques for the discovery of new allergens as well as for measuring the immune responses directed against them. Copyright © 2018 The Authors. Published by Elsevier GmbH.. All rights reserved.

  10. Immobilization of ɛ-polylysine onto the probe surface for molecular adsorption type endotoxin detection system

    NASA Astrophysics Data System (ADS)

    Ooe, Katsutoshi; Tsuji, Akihito; Nishishita, Naoki; Hirano, Yoshiaki

    2007-04-01

    Patients with renal failure become not able to expel the waste product, and they accumulate the toxic products for themselves. They therefore must use the hemodialysis to weed out the metabolic decomposition product. Hemodialysis for chronic renal failure is the most popular treatment method with artificial organs. However, hemodialysis patients must continue the treatment throughout their life, the results of long term extracorporeal dialysis, those patients develop the various complications and diseases, for example, dialysis amyloidosis etc. Dialysis amyloidosis is one of the refractory complications, and the prevention of this complication is important. Recently, endotoxin is thought to be the most likely cause of the complication. Endotoxin is one of the major cell wall components of gram-negative bacteria, and it forms the complex with proteins and lipopolysaccharide (LPS). It has various biological activities, e.g. attack of fever, when it gets mixed into human blood. In addition, it is known that large amount of endotoxin exists in living environment, and medicine is often contaminated with endotoxin. When contaminated dialyzing fluids are used to hemodialysis, above-mentioned dialysis amyloidosis is developed. Therefore, it is important that the detection and removal of endotoxin from dialyzing fluids. Until now, the measurement methods using Limulus Amebosyte Lysate (LAL) reagent were carried out as the tests for the presence of endotoxin. However, these methods include several different varieties of measurement techniques. The following are examples of them, gelatinization method, turbidimetric assay method, colorimetric assay method and fluoroscopic method. However, these techniques needed 30-60 minutes for the measurement. From these facts, they are not able to use as a "real-time endotoxin detector". The detection of endotoxin has needed to carry out immediately, for that reason, a new "real-time" detection method is desired. We focused attention to

  11. Enhanced in vivo IgE production and T cell polarization toward the type 2 phenotype in association with indoor exposure to VOC: results of the LARS study.

    PubMed

    Lehmann, I; Rehwagen, M; Diez, U; Seiffart, A; Rolle-Kampczyk, U; Richter, M; Wetzig, H; Borte, M; Herbarth, O

    2001-12-01

    The association between indoor exposure to volatile organic compounds (VOC), prevalence of allergic sensitization and cytokine secretion profile of peripheral T cells was studied in 3 year old children of the LARS study (Leipzig Allergy Risk Children Study) to investigate the role of VOC exposure as a risk factor for the development of atopic disease. Indoor VOC exposure was measured over a period of 4 weeks in infants' bedrooms using a passive sampling system. Specific IgE antibodies to food, indoor and outdoor allergens were measured by the Pharmacia CAP system and correlated to VOC exposure (n = 120). In addition, cytokine producing peripheral T cells (interleukin(IL)-4, interferon(IFN)-gamma) were measured in a subgroup of 28 children by means of intracellular cytokine staining. For the first time we were able to show that exposure to alkanes (C6, C9, C10) and aromatic compounds (toluene, o-xylene, m + p-xylene, 2-, 3- and 4-ethyl-toluene, chlorobenzene) may contribute to the risk of allergic sensitization to the food allergens milk and egg white (Odds ratios between 5.7 and 11.2). Moreover, significantly reduced numbers of CD3+/CD8+ peripheral T cells were found in children exposed to alkanes (C9-C13), naphthalene and chlorobenzene. Exposure to benzene, ethylbenzene and chlorobenzene was associated with higher percentages of IL-4 producing CD3+ T cells. Both an increase in IL-4 producing type 2 T cells and a reduction of IFN-gamma producing type 1 T cells may contribute to a type 2 skewed memory in response to allergens. Therefore, we suggest exposure to VOCs in association with allergic sensitization to be mediated by a T cell polarization toward the type 2 phenotype.

  12. AllerML: Markup Language for Allergens

    PubMed Central

    Ivanciuc, Ovidiu; Gendel, Steven M.; Power, Trevor D.; Schein, Catherine H.; Braun, Werner

    2011-01-01

    Many concerns have been raised about the potential allergenicity of novel, recombinant proteins into food crops. Guidelines, proposed by WHO/FAO and EFSA, include the use of bioinformatics screening to assess the risk of potential allergenicity or cross-reactivities of all proteins introduced, for example, to improve nutritional value or promote crop resistance. However, there are no universally accepted standards that can be used to encode data on the biology of allergens to facilitate using data from multiple databases in this screening. Therefore, we developed AllerML a markup language for allergens to assist in the automated exchange of information between databases and in the integration of the bioinformatics tools that are used to investigate allergenicity and cross-reactivity. As proof of concept, AllerML was implemented using the Structural Database of Allergenic Proteins (SDAP; http://fermi.utmb.edu/SDAP/) database. General implementation of AllerML will promote automatic flow of validated data that will aid in allergy research and regulatory analysis. PMID:21420460

  13. Broad application and optimization of a single wash-step for integrated endotoxin depletion during protein purification.

    PubMed

    Koziel, David; Michaelis, Uwe; Kruse, Tobias

    2018-08-01

    Endotoxins contaminate proteins that are produced in E. coli. High levels of endotoxins can influence cellular assays and cause severe adverse effects when administered to humans. Thus, endotoxin removal is important in protein purification for academic research and in GMP manufacturing of biopharmaceuticals. Several methods exist to remove endotoxin, but often require additional downstream-processing steps, decrease protein yield and are costly. These disadvantages can be avoided by using an integrated endotoxin depletion (iED) wash-step that utilizes Triton X-114 (TX114). In this paper, we show that the iED wash-step is broadly applicable in most commonly used chromatographies: it reduces endotoxin by a factor of 10 3 to 10 6 during NiNTA-, MBP-, SAC-, GST-, Protein A and CEX-chromatography but not during AEX or HIC-chromatography. We characterized the iED wash-step using Design of Experiments (DoE) and identified optimal experimental conditions for application scenarios that are relevant to academic research or industrial GMP manufacturing. A single iED wash-step with 0.75% (v/v) TX114 added to the feed and wash buffer can reduce endotoxin levels to below 2 EU/ml or deplete most endotoxin while keeping the manufacturing costs as low as possible. The comprehensive characterization enables academia and industry to widely adopt the iED wash-step for a routine, efficient and cost-effective depletion of endotoxin during protein purification at any scale. Copyright © 2018. Published by Elsevier B.V.

  14. Leakage of Microbial Endotoxin through the Implant-Abutment Interface in Oral Implants: An In Vitro Study.

    PubMed

    Garrana, Rhoodie; Mohangi, Govindrau; Malo, Paulo; Nobre, Miguel

    2016-01-01

    Background . Endotoxin initiates osteoclastic activity resulting in bone loss. Endotoxin leakage through implant abutment connections negatively influences peri-implant bone levels. Objectives . (i) To determine if endotoxin can traverse different implant-abutment connection (IAC) designs; (ii) to quantify the amount of endotoxins traversing the IAC; (iii) to compare the in vitro comportments of different IACs. Materials and Methods . Twenty-seven IACs were inoculated with E. coli endotoxin. Six of the twenty-seven IACs were external connections from one system (Southern Implants) and the remaining twenty-one IACs were made up of seven internal IAC types from four different implant companies (Straumann, Ankylos, and Neodent, Southern Implants). Results . Of the 27 IACs tested, all 6 external IACs leaked measurable amounts of endotoxin. Of the remaining 21 internal IACs, 9 IACs did not show measurable leakage whilst the remaining 12 IACs leaked varying amounts. The mean log endotoxin level was significantly higher for the external compared to internal types ( p = 0.015). Conclusion . Within the parameters of this study, we can conclude that endotoxin leakage is dependent on the design of the IAC. Straumann Synocta, Straumann Cross-fit, and Ankylos displayed the best performances of all IACs tested with undetectable leakage after 7 days. Each of these IACs incorporated a morse-like component in their design. Speculation still exists over the impact of IAC endotoxin leakage on peri-implant tissues in vivo; hence, further investigations are required to further explore this.

  15. The role of endotoxin in grain dust-induced lung disease.

    PubMed

    Schwartz, D A; Thorne, P S; Yagla, S J; Burmeister, L F; Olenchock, S A; Watt, J L; Quinn, T J

    1995-08-01

    To identify the role of endotoxin in grain dust-induced lung disease, we conducted a population-based, cross-sectional investigation among grain handlers and postal workers. The study subjects were selected by randomly sampling all grain facilities and post offices within 100 miles of Iowa City. Our study population consisted of 410 grain workers and 201 postal workers. Grain workers were found to be exposed to higher concentrations of airborne dust (p = 0.0001) and endotoxin (p = 0.0001) when compared with postal workers. Grain workers had a significantly higher prevalence of work-related (cough, phlegm, wheezing, chest tightness, and dyspnea) and chronic (usual cough or phlegm production) respiratory symptoms than postal workers. Moreover, after controlling for age, gender, and cigarette smoking status, work-related respiratory symptoms were strongly associated with the concentration of endotoxin in the bioaerosol in the work setting. The concentration of total dust in the bioaerosol was marginally related to these respiratory problems. After controlling for age, gender, and cigarette smoking status, grain workers were found to have reduced spirometric measures of airflow (FEV1, FEV1/FVC, and FEF25-75) and enhanced airway reactivity to inhaled histamine when compared with postal workers. Although the total dust concentration in the work environment appeared to have little effect on these measures of airflow obstruction, higher concentrations of endotoxin in the bioaerosol were associated with diminished measures of airflow and enhanced bronchial reactivity. Our results indicate that the concentration of endotoxin in the bioaerosol may be particularly important in the development of grain dust-induced lung disease.

  16. Acute Low-Dose Endotoxin Treatment Results in Improved Whole-Body Glucose Homeostasis in Mice

    PubMed Central

    Stevens, Joseph R.; McMillan, Ryan P.; Resendes, Justin T.; Lloyd, Shannon K.; Ali, Mostafa M.; Frisard, Madlyn I.; Hargett, Stefan; Keller, Susanna R.; Hulver, Matthew W.

    2017-01-01

    Background Obese individuals present with an increased inflammatory tone as compared to healthy, normal-weight individuals, which is associated with insulin resistance. One factor hypothesized to contribute to increased inflammation in obese and diabetic states is elevated blood endotoxin levels, a condition known as metabolic endotoxemia. In non-obese and insulin sensitive individuals, circulating endotoxin concentrations fluctuate over the course of the day with elevations in the post-prandial state that return to baseline levels in the post-absorptive state. Evidence suggests that high-fat feeding alters these fluctuations causing endotoxin levels to remain high throughout the day. The effects of alterations in endotoxin levels on glucose metabolism are not clearly understood. Purpose/Procedures The goal of this study was to determine the effects of both short-term and long-term increases in endotoxin (lipopolysaccharide, LPS) of a low magnitude on the glucose tolerance and insulin signaling in a human primary cell line as well as the effects of short-term endotoxin treatments on glucose homeostasis in a C57/Bl6 mouse model. First, we tested the hypothesis that short-term low-dose endotoxin treatments would augment insulin signaling and glycogen synthesis while long-term treatments would be disruptive in the cell culture model. Second, we examined if these short-term low dose treatments of endotoxin would contribute to similar improvements in whole-body glucose homeostasis in a mouse model. Main Findings Contrary to our initial hypothesis, short-term endotoxin treatment had no effect on insulin signaling or glycogen synthesis, however long-term treatment indeed decreased glycogen synthesis (P<.05). Interestingly, short-term endotoxin treatment resulted in significant improvements in glucose homeostasis in the mouse model (P<.01); which is believed to be at least partly attributed to an inhibitory action of LPS on liver glucose production. Conclusions This

  17. Acute low-dose endotoxin treatment results in improved whole-body glucose homeostasis in mice.

    PubMed

    Stevens, Joseph R; McMillan, Ryan P; Resendes, Justin T; Lloyd, Shannon K; Ali, Mostafa M; Frisard, Madlyn I; Hargett, Stefan; Keller, Susanna R; Hulver, Matthew W

    2017-03-01

    Obese individuals present with an increased inflammatory tone as compared to healthy, normal-weight individuals, which is associated with insulin resistance. One factor hypothesized to contribute to increased inflammation in obese and diabetic states is elevated blood endotoxin levels, a condition known as metabolic endotoxemia. In non-obese and insulin sensitive individuals, circulating endotoxin concentrations fluctuate over the course of the day with elevations in the post-prandial state that return to baseline levels in the post-absorptive state. Evidence suggests that high-fat feeding alters these fluctuations causing endotoxin levels to remain high throughout the day. The effects of alterations in endotoxin levels on glucose metabolism are not clearly understood. The goal of this study was to determine the effects of both short-term and long-term increases in endotoxin (lipopolysaccharide, LPS) of a low magnitude on the glucose tolerance and insulin signaling in a human primary cell line as well as the effects of short-term endotoxin treatments on glucose homeostasis in a C57/Bl6 mouse model. First, we tested the hypothesis that short-term low-dose endotoxin treatments would augment insulin signaling and glycogen synthesis while long-term treatments would be disruptive in the cell culture model. Second, we examined if these short-term low dose treatments of endotoxin would contribute to similar improvements in whole-body glucose homeostasis in a mouse model. Contrary to our initial hypothesis, short-term endotoxin treatment had no effect on insulin signaling or glycogen synthesis, however long-term treatment indeed decreased glycogen synthesis (P<.05). Interestingly, short-term endotoxin treatment resulted in significant improvements in glucose homeostasis in the mouse model (P<.01); which is believed to be at least partly attributed to an inhibitory action of LPS on liver glucose production. This research shows that low-magnitude, short-term changes in LPS

  18. Cockroach Allergen Exposure and Risk of Asthma

    PubMed Central

    Do, Danh C.; Zhao, Yilin; Gao, Peisong

    2015-01-01

    Cockroach sensitization is an important risk factor for the development of asthma. However, its underlying immune mechanisms and the genetic etiology for differences in allergic responses remain unclear. Cockroach allergens identification and their expression as biologically active recombinant proteins has provided a basis for studying the mechanisms regarding cockroach allergens induced allergic sensitization and asthma. Glycans in allergens may play a crucial role in the immunogenicity of allergic diseases. Protease-activated receptor (PAR)-2, Toll-like receptor (TLR), and C-type lectin receptors have been suggested to be important for the penetration of cockroach allergens through epithelial cells to mediate allergen uptake, dendritic cell maturation, antigen presenting cell (APC) function in T cell polarization, and cytokine production. Environmental pollutants, which often co-exist with the allergen, could synergistically elicit allergic inflammation, and aryl hydrocarbon receptor (AhR) activation and signaling may serve as a link between these two elements. Genetic factors may also play an important role in conferring the susceptibility to cockroach sensitization. Several genes have been associated with cockroach sensitization and asthma-related phenotypes. In this review, we will discuss the epidemiological evidence for cockroach allergen-induced asthma, cockroach allergens, the mechanisms regarding cockroach allergens induced innate immune responses, and the genetic basis for cockroach sensitization. PMID:26706467

  19. Personal exposure to dust and endotoxin in Robusta and Arabica coffee processing factories in Tanzania.

    PubMed

    Sakwari, Gloria; Mamuya, Simon H D; Bråtveit, Magne; Larsson, Lennart; Pehrson, Christina; Moen, Bente E

    2013-03-01

    Endotoxin exposure associated with organic dust exposure has been studied in several industries. Coffee cherries that are dried directly after harvest may differ in dust and endotoxin emissions to those that are peeled and washed before drying. The aim of this study was to measure personal total dust and endotoxin levels and to evaluate their determinants of exposure in coffee processing factories. Using Sidekick Casella pumps at a flow rate of 2l/min, total dust levels were measured in the workers' breathing zone throughout the shift. Endotoxin was analyzed using the kinetic chromogenic Limulus amebocyte lysate assay. Separate linear mixed-effects models were used to evaluate exposure determinants for dust and endotoxin. Total dust and endotoxin exposure were significantly higher in Robusta than in Arabica coffee factories (geometric mean 3.41 mg/m(3) and 10 800 EU/m(3) versus 2.10 mg/m(3) and 1400 EU/m(3), respectively). Dry pre-processed coffee and differences in work tasks explained 30% of the total variance for total dust and 71% of the variance for endotoxin exposure. High exposure in Robusta processing is associated with the dry pre-processing method used after harvest. Dust and endotoxin exposure is high, in particular when processing dry pre-processed coffee. Minimization of dust emissions and use of efficient dust exhaust systems are important to prevent the development of respiratory system impairment in workers.

  20. Personal Exposure to Dust and Endotoxin in Robusta and Arabica Coffee Processing Factories in Tanzania

    PubMed Central

    Sakwari, Gloria

    2013-01-01

    Introduction: Endotoxin exposure associated with organic dust exposure has been studied in several industries. Coffee cherries that are dried directly after harvest may differ in dust and endotoxin emissions to those that are peeled and washed before drying. The aim of this study was to measure personal total dust and endotoxin levels and to evaluate their determinants of exposure in coffee processing factories. Methods: Using Sidekick Casella pumps at a flow rate of 2l/min, total dust levels were measured in the workers’ breathing zone throughout the shift. Endotoxin was analyzed using the kinetic chromogenic Limulus amebocyte lysate assay. Separate linear mixed-effects models were used to evaluate exposure determinants for dust and endotoxin. Results: Total dust and endotoxin exposure were significantly higher in Robusta than in Arabica coffee factories (geometric mean 3.41mg/m3 and 10 800 EU/m3 versus 2.10mg/m3 and 1400 EU/m3, respectively). Dry pre-processed coffee and differences in work tasks explained 30% of the total variance for total dust and 71% of the variance for endotoxin exposure. High exposure in Robusta processing is associated with the dry pre-processing method used after harvest. Conclusions: Dust and endotoxin exposure is high, in particular when processing dry pre-processed coffee. Minimization of dust emissions and use of efficient dust exhaust systems are important to prevent the development of respiratory system impairment in workers. PMID:23028014

  1. Endotoxin induction of an inhibitor of plasminogen activator in bovine pulmonary artery endothelial cells

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

    Not Available

    The effects of bacterial lipopolysaccharide (endotoxin) on the fibrinolytic activity of bovine pulmonary artery endothelial cells were examined. Endotoxin suppressed the net fibrinolytic activity of cell extracts and conditioned media in a dose-dependent manner. The effects of endotoxin required at least 6 h for expression. Cell extracts and conditioned media contained a 44-kDa urokinase-like plasminogen activator. Media also contained multiple plasminogen activators with molecular masses of 65-75 and 80-100 kDa. Plasminogen activators in extracts and media were unchanged by treatment of cells with endotoxin. Diisopropyl fluorophosphate (DFP)-abolished fibrinolytic activity of extracts and conditioned media. DFP-treated samples from endotoxin-treated but notmore » untreated cells inhibited urokinase and tissue plasminogen activator, but not plasmin. Inhibitory activity was lost by incubation at pH 3 or heating to 56/sup 0/C for 10 min. These treatments did not affect inhibitory activity of fetal bovine serum. Incubation of /sup 125/I-urokinase with DFP-treated medium from endotoxin-treated cells produced an inactive complex with an apparent molecular mass of 80-85 kDa.« less

  2. Protection against hyperoxia by serum from endotoxin treated rats: absence of superoxide dismutase induction

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

    Berg, J.T.; Smith, R.M.

    Endotoxin greatly reduces lung injury and pleural effusions in adult rats exposed to normobaric hyperoxia (> 98% oxygen for 60 hours). This study reports that serum from endotoxin treated donor rats protects serum recipients against hyperoxic lung injury without altering lung superoxide dismutase (SOD) activity. Rats pretreated with endotoxin alone were protected and exhibited an increase in lung SOD activity as previously reported by others. Protection by serum was not due to the transfer of residual endotoxin or SOD. These results show, that protection from oxygen toxicity can occur in rats without an increase in lung SOD and suggest thatmore » a serum factor may be involved.« less

  3. Plasma endotoxin activity in Eastern grey kangaroos (Macropus giganteus) with lumpy jaw disease

    PubMed Central

    SOTOHIRA, Yukari; SUZUKI, Kazuyuki; OTSUKA, Marina; TSUCHIYA, Masakazu; SHIMAMORI, Toshio; NISHI, Yasunobu; TSUKANO, Kenji; ASAKAWA, Mitsuhiko

    2017-01-01

    Progressive pyogranulomatous osteomyelitis involving the mandible or maxilla of captive macropods, referred to as “Lumpy jaw disease (LJD)”, is one of the most significant causes of illness and death in captive macropods. The aim of the present study was to evaluate the relationship between the severity of LJD and plasma endotoxin activity in kangaroos. Plasma samples obtained from moderate (n=24) and severe LJD (n=12), and healthy kangaroos (n=46), were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. Plasma endotoxin activity was measured using the Limulus amebocyte lysate (LAL)-kinetic turbidimetric (KT) assay. Plasma endotoxin activity was higher in kangaroos with severe LJD (0.199 ± 0.157 EU/ml) than in those with moderate LJD (0.051 ± 0.012 EU/ml, P<0.001) and healthy controls (0.057 ± 0.028 EU/ml, P<0.001). Our results suggest that the severity of LJD in captive macropods may be related to the plasma endotoxin activity. PMID:28484148

  4. Plasma endotoxin activity in Eastern grey kangaroos (Macropus giganteus) with lumpy jaw disease.

    PubMed

    Sotohira, Yukari; Suzuki, Kazuyuki; Otsuka, Marina; Tsuchiya, Masakazu; Shimamori, Toshio; Nishi, Yasunobu; Tsukano, Kenji; Asakawa, Mitsuhiko

    2017-06-29

    Progressive pyogranulomatous osteomyelitis involving the mandible or maxilla of captive macropods, referred to as "Lumpy jaw disease (LJD)", is one of the most significant causes of illness and death in captive macropods. The aim of the present study was to evaluate the relationship between the severity of LJD and plasma endotoxin activity in kangaroos. Plasma samples obtained from moderate (n=24) and severe LJD (n=12), and healthy kangaroos (n=46), were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. Plasma endotoxin activity was measured using the Limulus amebocyte lysate (LAL)-kinetic turbidimetric (KT) assay. Plasma endotoxin activity was higher in kangaroos with severe LJD (0.199 ± 0.157 EU/ml) than in those with moderate LJD (0.051 ± 0.012 EU/ml, P<0.001) and healthy controls (0.057 ± 0.028 EU/ml, P<0.001). Our results suggest that the severity of LJD in captive macropods may be related to the plasma endotoxin activity.

  5. Dopexamine reverses colonic but not gastric mucosal perfusion defects in lethal endotoxin shock.

    PubMed

    Tenhunen, J J; Martikainen, T J; Uusaro, A; Ruokonen, E

    2003-12-01

    Whilst dopexamine appears to increase overall splanchnic blood flow in postoperative and septic patients, the effects on gastric mucosal perfusion are controversial and based on concomitantly increasing mucosal to arterial PCO(2) gradients (PdCO(2)). We hypothesized that dopexamine alters splanchnic blood flow distribution and metabolism during experimental endotoxin shock and modifies the inflammatory response induced by endotoxin. In an experiment with anaesthetized normovolaemic, normoventilated pigs, 21 animals were randomized into: (i). subacute lethal endotoxin shock for 14 h (n=7 at baseline); (ii). endotoxin shock with dopexamine infusion (aiming to exceed baseline cardiac output, n=7); or (iii). controls (n=7). Regional blood flow and metabolism were monitored. Endotoxin produced a hypodynamic phase followed by a normo/hyperdynamic, hypotensive phase. Despite increasing systemic blood flow in response to dopexamine, proportional splanchnic blood flow decreased during the hypodynamic phase. Dopexamine gradually decreased fractional coeliac trunk flow, while fractional superior mesenteric arterial flow increased. Dopexamine induced early arterial hyperlactataemia and augmented the gastric PdCO(2) gradient while colonic luminal lactate release and colonic PdCO(2) gradient were reversed. Dopexamine did not modify the inflammatory response as evaluated by arterial IL-1beta and IL-6 concentrations. Dopexamine protects colonic, but not gastric mucosal epithelium in experimental endotoxin shock. This may be related to redistribution of blood flow within the splanchnic circulation.

  6. Effects of Maillard reaction on allergenicity of buckwheat allergen Fag t 3 during thermal processing.

    PubMed

    Yang, Zhen-Huang; Li, Chen; Li, Yu-Ying; Wang, Zhuan-Hua

    2013-04-01

    Fag t 3 is a major allergenic protein in tartary buckwheat. The Maillard reaction commonly occurs in food processing, but few studies have been conducted on the influence of thermal processing on the allergenic potential of buckwheat allergen. The aim of the present study was to investigate the effects of autologous plant polysaccharides on the immunoreactivity of buckwheat Fag t 3 (11S globulin) following the Maillard reaction. Fag t 3 and crude polysaccharides were prepared from tartary buckwheat (Fagopyrum tataricum) flour. After heating, the polysaccharides were covalently linked to Fag t 3 via a Maillard reaction, and the IgE/IgG-binding properties of Fag t 3 decreased dramatically, with significant changes also being observed in the electrophoretic mobility, secondary structure and solubility of the glycated Fag t 3. The great influence of glycation on IgE/IgG binding to Fag t 3 was correlated with a significant change in the structure and epitopes of the allergenic protein. These data indicated that conjugation of polysaccharides to Fag t 3 markedly reduced the allergen's immunoreactivity. Glycation that occurs via the Maillard reaction during the processing of buckwheat food may be an efficient method to reduce Fag t 3 allergenicity. © 2012 Society of Chemical Industry.

  7. Enhanced innate immune responsiveness and intolerance to intestinal endotoxins in human biliary epithelial cells contributes to chronic cholangitis.

    PubMed

    Mueller, Tobias; Beutler, Claudia; Picó, Almudena Hurtado; Shibolet, Oren; Pratt, Daniel S; Pascher, Andreas; Neuhaus, Peter; Wiedenmann, Bertram; Berg, Thomas; Podolsky, Daniel K

    2011-11-01

    Pattern recognition receptors (PRRs) orchestrate the innate immune defence in human biliary epithelial cells (BECs). Tight control of PRR signalling provides tolerance to physiological amounts of intestinal endotoxins in human bile to avoid constant innate immune activation in BECs. We wanted to determine whether inappropriate innate immune responses to intestinal endotoxins contribute to the development and perpetuation of chronic biliary inflammation. We examined PRR-mediated innate immune responses and protective endotoxin tolerance in primary BECs isolated from patients with primary sclerosing cholangitis (PSC), alcoholic liver disease and patients without chronic liver disease. Expression studies comprised northern blots, RT-PCR, Western blots and immunocytochemistry. Functional studies comprised immuno-precipitation Western blots, FACS for endotoxin uptake, and NF-κB activation assays and ELISA for secreted IL-8 and tumour necrosis factor (TNF)-α. Primary BECs from explanted PSC livers showed reversibly increased TLR and NOD protein expression and activation of the MyD88/IRAK signalling complex. Consecutively, PSC BECs exhibited inappropriate innate immune responses to endotoxins and did not develop immune tolerance after repeated endotoxin exposures. This endotoxin hyper-responsiveness was probably because of the stimulatory effect of abundantly expressed IFN-γ and TNF-α in PSC livers, which stimulated TLR4-mediated endotoxin signalling in BECs, leading to increased TLR4-mediated endotoxin incorporation and impaired inactivation of the TLR4 signalling cascade. As TNF-α inhibition partly restored protective innate immune tolerance, endogenous TNF-α secretion probably contributed to inappropriate endotoxin responses in BECs. Inappropriate innate immune responses to intestinal endotoxins and subsequent endotoxin intolerance because of enhanced PRR signalling in BECs probably contribute to chronic cholangitis. © 2011 John Wiley & Sons A/S.

  8. Rapid detection of bacterial endotoxins in ophthalmic viscosurgical device materials by direct analysis in real time mass spectrometry.

    PubMed

    Li, Hongli; Hitchins, Victoria M; Wickramasekara, Samanthi

    2016-11-02

    Bacterial endotoxins are lipopolysaccharides bound to the bacterial cell wall and released when bacteria rupture or disintegrate. Possible contamination of endotoxin in ophthalmic devices can cause a painful eye inflammation or result in toxic anterior segment syndrome after cataract surgery. Measurement of bacterial endotoxin in medical device materials is difficult since endotoxin binds with polymer matrix and some of the materials are very viscous and non-water soluble, where traditional enzyme-based Limulus amebocyte lysate (LAL) assay cannot be applied. Here we propose a rapid and high throughput ambient ionization mass spectrometric (MS) method using direct analysis in real time (DART) for the evaluation of endotoxin contamination in medical device materials. Large and structurally complex endotoxin instantaneously breaks down into low-mass characteristic fragment ions using DART and is detected by MS in both positive and negative ion modes. This method enables the identification and separation of endotoxin from medical materials with a detection limit of 0.03 ng mL -1 endotoxins in aqueous solution. Ophthalmic viscosurgical device materials including sodium hyaluronate (NaHA), non-water soluble perfluoro-n-octane (PFO) and silicone oil (SO) were spiked with different known concentrations of endotoxin and analyzed by DART MS, where the presence of endotoxin was successfully detected and featured small mass fragment ions were generated for NaHA, PFO and SO as well. Current findings showed the feasibility of measuring endotoxin contamination in medical device materials using DART-MS, which can lead to a one-step analysis of endotoxins in different matrices, avoiding any potential contamination during sample pre-treatment steps. Published by Elsevier B.V.

  9. Endotoxin levels correlate positively with a sedentary lifestyle and negatively with highly trained subjects.

    PubMed

    Lira, Fabio S; Rosa, Jose C; Pimentel, Gustavo D; Souza, Hélio A; Caperuto, Erico C; Carnevali, Luiz C; Seelaender, Marília; Damaso, Ana R; Oyama, Lila M; de Mello, Marco T; Santos, Ronaldo V

    2010-08-04

    A sedentary lifestyle increases the risk of developing cardiovascular disease, obesity, and diabetes. This phenomenon is supported by recent studies suggesting a chronic, low-grade inflammation status. Endotoxin derived from gut flora may be key to the development of inflammation by stimulating the secretion of inflammatory factors. This study aimed to examine plasma inflammatory markers and endotoxin levels in individuals with a sedentary lifestyle and/or in highly trained subjects at rest. Fourteen male subjects (sedentary lifestyle n = 7; highly trained subjects n = 7) were recruited. Blood samples were collected after an overnight fast (approximately 12 h). The plasmatic endotoxin, plasminogen activator inhibitor type-1 (PAI-1), monocyte chemotactic protein-1 (MCP1), ICAM/CD54, VCAM/CD106 and lipid profile levels were determined. Endotoxinemia was lower in the highly trained subject group relative to the sedentary subjects (p < 0.002). In addition, we observed a positive correlation between endotoxin and PAI-1 (r = 0.85, p < 0.0001), endotoxin and total cholesterol (r = 0.65; p < 0.01), endotoxin and LDL-c (r = 0.55; p < 0.049) and endotoxin and TG levels (r = 0.90; p < 0.0001). The plasma levels of MCP-1, ICAM/CD54 and VCAM/CD106 did not differ. These results indicate that a lifestyle associated with high-intensity and high-volume exercise induces favorable changes in chronic low-grade inflammation markers and may reduce the risk for diseases such as obesity, diabetes and cardiovascular diseases.

  10. Challenges and Path Forward on Mandatory Allergen Labeling and Voluntary Precautionary Allergen Labeling for a Global Company.

    PubMed

    Yeung, Jupiter; Robert, Marie-Claude

    2018-01-01

    For food manufacturers, the label on a food package is a tool meant to alert consumers to the presence of specific allergens, allowing consumers to make informed decisions and not unnecessarily limit their food choices. Mandatory allergen labeling is used when the allergen is an intentionally added ingredient, whereas voluntary allergen labeling is used when the presence of the allergen is unintentional and may be in the finished product as a result of cross-contact. In a globalized economy, ensuring food safety is a growing challenge for manufacturers. When ingredients and technologies are sourced worldwide from multiple business partners, complexity rises, which can increase the chance for errors, leading to potential harm. Threshold science, Voluntary Incidental Trace Allergen Labelling (VITAL) reference doses, fit-for-purpose analytical technology, and common sense enable us to optimize allergen management for the benefit of allergic consumers. This is a good strategy because all stakeholders share the common goal of making foods safe and wholesome for all. Herein, we recommend that (1) senior management make science-based thresholds a priority for both regulatory authorities and the food industry; (2) VITAL 2.0 be adopted as a risk assessment and risk management tool for precautionary allergen labeling (PAL); (3) a standardized message for PAL, i.e., "may contain x," be used to make it easily understandable to allergic consumers so they can make informed food choices; and (4) validated fit-for-purpose allergen methods be used to meet analytical needs. This is an opportunity for us to speak with one voice and demonstrate that food safety is not a competitive issue, but a shared responsibility. This approach could significantly improve allergic consumers' lives.

  11. Effects of food processing on food allergens.

    PubMed

    Sathe, Shridhar K; Sharma, Girdhari M

    2009-08-01

    Food allergies are on the rise in Western countries. With the food allergen labeling requirements in the US and EU, there is an interest in learning how food processing affects food allergens. Numerous foods are processed in different ways at home, in institutional settings, and in industry. Depending on the processing method and the food, partial or complete removal of the offending allergen may be possible as illustrated by reduction of peanut allergen in vitro IgE immunoreactivity upon soaking and blanching treatments. When the allergen is discretely located in a food, one may physically separate and remove it from the food. For example, lye peeling has been reported to produce hypoallergenic peach nectar. Protein denaturation and/or hydrolysis during food processing can be used to produce hypoallergenic products. This paper provides a short overview of basic principles of food processing followed by examples of their effects on food allergen stability. Reviewed literature suggests assessment of processing effects on clinically relevant reactivity of food allergens is warranted.

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

    PubMed Central

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

    2017-01-01

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

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

    PubMed

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

    2017-03-01

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

  14. A recombinant isoform of the Ole e 7 olive pollen allergen assembled by de novo mass spectrometry retains the allergenic ability of the natural allergen.

    PubMed

    Oeo-Santos, Carmen; Mas, Salvador; Benedé, Sara; López-Lucendo, María; Quiralte, Joaquín; Blanca, Miguel; Mayorga, Cristobalina; Villalba, Mayte; Barderas, Rodrigo

    2018-06-05

    The allergenic non-specific lipid transfer protein Ole e 7 from olive pollen is a major allergen associated with severe symptoms in areas with high olive pollen levels. Despite its clinical importance, its cloning and recombinant production has been unable by classical approaches. This study aimed at determining by mass-spectrometry based proteomics its complete amino acid sequence for its subsequent expression and characterization. To this end, the natural protein was in-2D-gel tryptic digested, and CID and HCD fragmentation spectra obtained by nLC-MS/MS analyzed using PEAKS software. Thirteen out of the 457 de novo sequenced peptides obtained allowed assembling its full-length amino acid sequence. Then, Ole e 7-encoding cDNA was synthesized and cloned in pPICZαA vector for its expression in Pichia pastoris yeast. The analyses by Circular Dichroism, and WB, ELISA and cell-based tests using sera and blood from olive pollen-sensitized patients showed that rOle e 7 mostly retained the structural, allergenic and antigenic properties of the natural allergen. In summary, rOle e 7 allergen assembled by de novo peptide sequencing by MS behaved immunologically similar to the natural allergen scarcely isolated from pollen. Olive pollen is an important cause of allergy. The non-specific lipid binding protein Ole e 7 is a major allergen with a high incidence and a phenotype associated to severe clinical symptoms. Despite its relevance, its cloning and recombinant expression has been unable by classical techniques. Here, we have inferred the primary amino acid sequence of Ole e 7 by mass-spectrometry. We separated Ole e 7 isolated from pollen by 2DE. After in-gel digestion with trypsin and a direct analysis by nLC-MS/MS in an LTQ-Orbitrap Velos, we got the complete de novo sequenced peptides repertoire that allowed the assembling of the primary sequence of Ole e 7. After its protein expression, purification to homogeneity, and structural and immunological characterization

  15. Novel structure of cockroach allergen Bla g 1 has implications for allergenicity and exposure assessment

    PubMed Central

    Mueller, Geoffrey A.; Pedersen, Lars C.; Lih, Fred B.; Glesner, Jill; Moon, Andrea F.; Chapman, Martin D.; Tomer, Kenneth B.; London, Robert E.; Pomés, Anna

    2013-01-01

    Background Sensitization to cockroach allergens is a major risk factor for asthma. The cockroach allergen Bla g 1 has multiple repeats of ~100 amino acids, but the fold of the protein and the biological function are unknown. Objective To determine the structure of Bla g 1, investigate the implications for allergic disease, and standardize cockroach exposure assays. Methods Natural Bla g 1 and recombinant constructs were compared by ELISA using specific murine IgG and human IgE. The structure of Bla g 1 was determined by X-ray crystallography. Mass spectrometry and NMR were utilized to examine ligand-binding properties of the allergen. Results The structure of a recombinant Bla g 1 construct with comparable IgE and IgG reactivity to the natural allergen was solved by X-ray crystallography. The Bla g 1 repeat forms a novel fold with 6 helices. Two repeats encapsulate a large and nearly spherical hydrophobic cavity, defining the basic structural unit. Lipids in the cavity varied depending on the allergen origin. Palmitic, oleic and stearic acids were associated with nBla g 1 from cockroach frass. One Unit of Bla g 1 was equivalent to 104 ng of allergen. Conclusions Bla g 1 has a novel fold with a capacity to bind various lipids, which suggests a digestive function associated with non-specific transport of lipid molecules in cockroaches. Defining the basic structural unit of Bla g 1 facilitates the standardization of assays in absolute units for the assessment of environmental allergen exposure. PMID:23915714

  16. Public protection - reliable allergen risk management

    NASA Astrophysics Data System (ADS)

    Janković, V.; Popov Raljić, J.; Đorđević, V.

    2017-09-01

    Consumers with potentially fatal food allergies are dependent on correct product labelling to protect their health. The food industry is responsible for providing every detail consumers need to make informed decisions. Considering public health, food suppliers have to monitor the presence of allergens, prevent cross-contamination and label products accurately. Allergen labelling of food products, drinks and non pre-packed food and drink products is clearly defined with legal regulations. To achieve this, a complete understanding of each product’s allergenic ingredients is needed and cross-contamination of food with allergens must be avoided. Raw materials need to be checked, every ingredient must be verified and every single allergen has to be stipulated. A mislabeled product could be recalled at potential cost, financially damaging business and at the same time, negatively impacting brand and reputation.

  17. [Endotoxin Contamination and Correlation with Other Water Quality Parameters of Groundwater from Self-Contained Wells in Beijing].

    PubMed

    Zhang, Can; Liu, Wen-jun; Ao, Lu; Shi, Yun; An, Dai-zhi; Liu, Zhi-ping

    2015-12-01

    A survey of endotoxin activity in groundwater from 14 self-contained wells in PLA units stationed in Beijing was conducted by the kinetic-turbid assay of Tachypleus Amebocyte Lysate (TAL). Bacteriological parameters, including total cell counts detected by flow cytometry, heterotrophic plate counts (HPC), standard plate counts and total coliforms were analyzed. Additionally, suspended particles, turbidity, dissolved organic carbon (DOC), and UV₂₅₄ were investigated. Total endotoxin activities ranged from 0. 15 to 13.20 EU · mL⁻¹, free endotoxin activities ranged from 0.10 to 5.29 EU · mL⁻¹ and bound endotoxin activities ranged from 0.01 to 8.60 EU · mL⁻¹. Most of the endotoxins in heavily contaminated groundwater existed as bound endotoxins. As for total endotoxins, the sequence of correlation coefficients with other parameters was total cell counts (r = 0.88 ) > HPC (r = 0.79) > DOC (r = 0.77) > UV₂₅₄ (r = 0.57) > total coliforms (r = 0.50) > standard plate counts (r = 0.49) = turbidity (r = 0. 49) > total particles (r = 0.41). The sequence of correlations of the bound endotoxins with other parameters was total cell counts (r = 0.81) > HPC (r = 0.66) > total coliforms (r = 0.65) > turbidity (r = 0.62) > total particles (r = 0.58) > standard plate counts (r = 0.22). Free endotoxins were correlated with DOC and UV₂₅₄, r = 0.58 and 0.26, respectively. Result showed free endotoxins had a higher correlation with DOC, and a lower correlation with UV₂₅₄.

  18. Specific IgE and IgG measured by the MeDALL allergen-chip depend on allergen and route of exposure: The EGEA study.

    PubMed

    Siroux, Valérie; Lupinek, Christian; Resch, Yvonne; Curin, Mirela; Just, Jocelyne; Keil, Thomas; Kiss, Renata; Lødrup Carlsen, Karin; Melén, Erik; Nadif, Rachel; Pin, Isabelle; Skrindo, Ingebjørg; Vrtala, Susanne; Wickman, Magnus; Anto, Josep Maria; Valenta, Rudolf; Bousquet, Jean

    2017-02-01

    The nature of allergens and route and dose of exposure may affect the natural development of IgE and IgG responses. We sought to investigate the natural IgE and IgG responses toward a large panel of respiratory and food allergens in subjects exposed to different respiratory allergen loads. A cross-sectional analysis was conducted in 340 adults of the EGEA (Epidemiological study of the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy) (170 with and 170 without asthma) cohort. IgE and IgG responses to 47 inhalant and food allergen components were analyzed in sera using allergen microarray and compared between 5 French regions according to the route of allergen exposure (inhaled vs food allergens). Overall 48.8% of the population had allergen-specific IgE levels of 0.3 ISAC standardized units (ISU) or more to at least 1 of the 47 allergens with no significant differences across the regions. For ubiquitous respiratory allergens (ie, grass, olive/ash pollen, house dust mites), specific IgE did not show marked differences between regions and specific IgG (≥0.5 ISU) was present in most subjects everywhere. For regionally occurring pollen allergens (ragweed, birch, cypress), IgE sensitization was significantly associated with regional pollen exposure. For airborne allergens cross-reacting with food allergens, frequent IgG recognition was observed even in regions with low allergen prevalence (Bet v 1) or for allergens less frequently recognized by IgE (profilins). The variability in allergen-specific IgE and IgG frequencies depends on exposure, route of exposure, and overall immunogenicity of the allergen. Allergen contact by the oral route might preferentially induce IgG responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  19. Immunoproteomic tools are used to identify masked allergens: Ole e 12, an allergenic isoflavone reductase from olive (Olea europaea) pollen.

    PubMed

    Castro, Lourdes; Crespo, Jesús F; Rodríguez, Julia; Rodríguez, Rosalía; Villalba, Mayte

    2015-12-01

    Proteins performing important biochemical activities in the olive tree (Olea europaea) pollen have been identified as allergens. One novel 37-kDa protein seems to be associated to the IgE-binding profile of a group of patients suffering allergy to peach and olive pollen. Three previously described olive pollen allergens exhibit very similar molecular mass. Our objective was to identify this allergen by using immunoproteomic approaches. After 2D-electrophoresis and mass spectrometry, peptide sequences from several IgE-binding spots, allowed identifying this new allergen, as well as cloning and DNA sequencing of the corresponding gene. The allergen, named Ole e 12, is a polymorphic isoflavone reductase-like protein of 308 amino acids showing 80% and 74% identity with birch and pear allergens, Bet v 6 and Pyr c 5, respectively. A prevalence of 33% in the selected population is in contrast to 4%-10% in groups of subjects suffering from pollinosis. Recombinant allergen was produced in Escherichia coli, and deeply characterised. Immunoblotting and ELISA detection as well as inhibition experiments were performed with polyclonal antisera and allergic patients' sera. The recombinant allergen retains the IgE reactivity of its natural counterpart. Close structural and immunological relationships between members of this protein family were supported by their IgG recognition in vegetable species. In summary, Ole e 12 is a minor olive pollen allergen, which gains relevance in patients allergic to peach with olive pollinosis. Proteomic approaches used to analyse this allergen provide useful tools to identify hidden allergens, relevant for several allergic populations and thus complete allergenic panels. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  1. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  2. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  3. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  4. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  5. PmrD is Required for Modifications to Escherichia Coli Endotoxin that Promote Antimicrobial Resistance

    DTIC Science & Technology

    2015-01-20

    is unlimited. PmrD Is Required for Modifications to Escherichia coli Endotoxin That Promote Antimicrobial Resistance The views, opinions and/or...East 27th Street Suite 5.300 Austin, TX 78712 -1532 ABSTRACT PmrD Is Required for Modifications to Escherichia coli Endotoxin That Promote...PhoPQ and PmrAB in E. coli than previously understood. PmrD Is Required for Modifications to Escherichia coli Endotoxin That Promote Antimicrobial

  6. Clinical efficacy of EDTA ultrasonic activation in the reduction of endotoxins and cultivable bacteria.

    PubMed

    Herrera, D R; Martinho, F C; de-Jesus-Soares, A; Zaia, A A; Ferraz, C C R; Almeida, J F A; Gomes, B P F A

    2017-10-01

    This clinical study was conducted to investigate the influence of 17% ethylenediaminetetraacetic acid (EDTA) ultrasonic activation after chemomechanical preparation (CMP) on eliminating/reducing oral bacterial lipopolysaccharides (known as endotoxins) and cultivable bacteria in teeth with pulp necrosis and apical periodontitis. Samples were taken from 24 root canals at several clinical periods: S1 - before CMP; S2 - after CMP; S3 - after EDTA: G1 - with ultrasonic activation (n = 12) and G2 - without ultrasonic activation (n = 12). Root canals were instrumented using Mtwo rotary files. Culture techniques were used to determine the number of colony-forming units (CFU). Limulus amebocyte lysate (LAL) was used to measure endotoxin levels. Friedman's and Wilcoxon signed-rank tests were used to compare the amount of bacteria and endotoxin levels in each period (P < 0.05). Endotoxins and cultivable bacteria were recovered in 100% of the initial samples (S1). CMP was effective in reducing endotoxins and bacterial load (all with P < 0.05). Higher values of endotoxin reduction were achieved with EDTA ultrasonic activation [G1, 0.02 EU mL -1 (range 0.01-0.75)] compared with the no activation group [G2, 1.13 EU mL -1 (range 0.01-8.34)] (P < 0.05). Regarding bacterial reduction, no statistically significant difference was found in S3, regardless of the group (G1, G2, P > 0.05). Chemomechanical preparation was effective in reducing bacteria and endotoxins, but could not completely eliminate them. The ultrasonic activation of EDTA was effective in further reducing endotoxin levels in the root canals of teeth with pulp necrosis and apical periodontitis. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  7. AllerML: markup language for allergens.

    PubMed

    Ivanciuc, Ovidiu; Gendel, Steven M; Power, Trevor D; Schein, Catherine H; Braun, Werner

    2011-06-01

    Many concerns have been raised about the potential allergenicity of novel, recombinant proteins into food crops. Guidelines, proposed by WHO/FAO and EFSA, include the use of bioinformatics screening to assess the risk of potential allergenicity or cross-reactivities of all proteins introduced, for example, to improve nutritional value or promote crop resistance. However, there are no universally accepted standards that can be used to encode data on the biology of allergens to facilitate using data from multiple databases in this screening. Therefore, we developed AllerML a markup language for allergens to assist in the automated exchange of information between databases and in the integration of the bioinformatics tools that are used to investigate allergenicity and cross-reactivity. As proof of concept, AllerML was implemented using the Structural Database of Allergenic Proteins (SDAP; http://fermi.utmb.edu/SDAP/) database. General implementation of AllerML will promote automatic flow of validated data that will aid in allergy research and regulatory analysis. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Detection of allergen sources in the homes of sensitized children.

    PubMed

    Álvarez-Chávez, Clara R; Flores-Bernal, José L; Esquer-Peralta, Javier; Munguía-Vega, Nora E; Corella-Madueño, María A G; Rascón-Careaga, Antonio; Turcotte, David; Velázquez-Contreras, Luis E

    2016-11-01

    To identify the presence of environmental factors linked to the onset of allergies and asthma in the homes of children participating in an early detection program that were identified with sensitivity to common allergens in the region of Sonora, Mexico. A walkthrough assessment was carried out in the homes of sensitized children; the research tools were the questionnaire and environmental checklist proposed by the Lowell Healthy Homes Program of the University of Massachusetts-Lowell. The results showed the presence of environmental allergen sources, to which most of the children in the study are sensitized, as well as the environmental conditions and habits that determine the quality of the indoor air of the households, were both related to triggering allergies and asthma in this population. A statistically significant association was found between the visual observation of dust inside homes and the sensitivity of children to dust mites. Dust found inside the home was the most relevant environmental factor related to positive cases of IgE in children. Early detection of allergies in children in the study and the methodology used in this investigation provided a useful framework for the design of plans and intervention alternatives in these homes to prevent the development of allergies and asthma panorama. These plans should be designed with a multidisciplinary approach to impact social, environmental and economic benefits in the family, improving the living conditions of the study population and contributing to the sustainable development goals of the United Nations for 2030.

  9. Effect of oleic acid on the allergenic properties of peanut and cashew allergens

    USDA-ARS?s Scientific Manuscript database

    Oleic acid is the major fatty acid in peanuts and cashews. There is limited information about its effect on peanut and cashew allergens during heating. The objective was to determine if heat treatment with oleic acid changes the allergenic properties of these nut proteins. Peanut and cashew protein...

  10. Mapping the areas sensitive to long-term endotoxin tolerance in the rat brain: a c-fos mRNA study.

    PubMed

    Vallès, Astrid; Martí, Octavi; Armario, Antonio

    2005-06-01

    We have recently found that a single endotoxin administration to rats reduced the hypothalamic-pituitary-adrenal response to another endotoxin administration 4 weeks later, which may be an example of the well-known phenomenon of endotoxin tolerance. However, the time elapsed between the two doses of endotoxin was long enough to consider the above results as an example of late tolerance, whose mechanisms are poorly characterized. To know if the brain plays a role in this phenomenon and to characterize the putative areas involved, we compared the c-fos mRNA response after a final dose of endotoxin in animals given vehicle or endotoxin 4 weeks before. Endotoxin caused a widespread induction of c-fos mRNA in the brain, similar to that previously reported by other laboratories. Whereas most of the brain areas were not sensitive to the previous experience with endotoxin, a few showed a reduced response in endotoxin-pretreated rats: the parvocellular and magnocellular regions of the paraventricular hypothalamic nucleus, the central amygdala, the lateral division of the bed nucleus and the locus coeruleus. We hypothesize that late tolerance to endotoxin may involve plastic changes in the brain, likely to be located in the central amygdala. The reduced activation of the central amygdala in rats previously treated with endotoxin may, in turn, reduce the activation of other brain areas, including the hypothalamic paraventicular nucleus.

  11. Recent development in recombinant food allergen production (abstract)

    USDA-ARS?s Scientific Manuscript database

    Whether for understanding the properties of food allergens or for manufacturing vaccines for allergen-specific immunotherapy, well characterized pure allergens are required. This often necessitate the use of recombinant technology in obtaining food allergens due to the very low amounts of their natu...

  12. A method for in Vivo radiolabeling Bacillus thuringiensis native δ-endotoxin crystals

    Treesearch

    C. Noah Koller; Leah S. Bauer; Robert M. Hollingworth

    1995-01-01

    The entomocidal CryIIIA δ-endotoxin protein of Bacillus thuringiensis var. tenebrionis is distinctive in chemistry and host range. In contrast to other δ-endotoxins, the CryIIIA parasporal crystals are toxic within the acidic midgut environment of several coleopteran species, particularly those in the family...

  13. Endotoxin concentration in neutropenic patients with suspected gram-negative sepsis: correlation with clinical outcome and determination of anti-endotoxin core antibodies during therapy with polyclonal immunoglobulin M-enriched immunoglobulins.

    PubMed Central

    Behre, G; Schedel, I; Nentwig, B; Wörmann, B; Essink, M; Hiddemann, W

    1992-01-01

    We carried out a study in patients with severe neutropenia from hematologic malignancy and suspected gram-negative sepsis to evaluate the clinical significance of endotoxin concentrations in plasma before and during a therapeutic intervention with a human polyclonal immunoglobulin M (IgM)-enriched immunoglobulin preparation (Pentaglobin; Biotest, Dreieich, Germany). Twenty-one patients with acute leukemia or non-Hodgkin's lymphoma entered the study upon the development of clinical signs of gram-negative sepsis and received the IgM-enriched immunoglobulin preparation every 6 h for 3 days (total dose, 1.3 liter with 7.8 g of IgM, 7.8 g of IgA, and 49.4 g of IgG), in addition to standardized antibiotic treatment. Concentrations of endotoxin and IgM and IgG antibodies against lipid A and Re lipopolysaccharide (LPS) in plasma were determined by a modified chromogenic Limulus amebocyte lysate test and semiquantitative enzyme linked immunosorbent assay, respectively, before each immunoglobulin infusion and during the following 25 days. Seventeen patients were endotoxin positive; in five of these patients, gram-negative infection was confirmed by microbiologic findings. Prior to therapy, endotoxemia correlated significantly with the occurrence of fever, and a quantitative correlation between the endotoxin concentration and body temperature was found during the individual course of infection in 8 of the 17 patients. Overall mortality from endotoxin-positive sepsis was 41% (7 of 17) and 64% (7 of 11) in patients with symptoms of septic shock. Nonsurvivors had significantly higher maximum concentration of endotoxin in plasma compared with those of survivors at the first study day (median of 126 versus 34 pg/ml; P < 0.05) and during the whole septic episode (median of 126 versus 61 pg/ml; P < 0.05). In survivors, immunoglobulin therapy resulted in a significant decrease in endotoxin levels in plasma within the initial 18-h treatment period, from a pretreatment median value of

  14. Fungal exposure, atopy, and asthma exacerbations in Puerto Rican children.

    PubMed

    Blatter, Joshua; Forno, Erick; Brehm, John; Acosta-Pérez, Edna; Alvarez, María; Colón-Semidey, Angel; Thorne, Peter S; Metwali, Nervana; Canino, Glorisa; Celedón, Juan C

    2014-07-01

    Glucan is a component of the fungal cell wall that is used as a marker of fungal exposure. Little is known about indoor glucan, atopy, and asthma exacerbations among children living in tropical environments such as Puerto Rico. Our objective was to examine whether glucan exposure is associated with degree of atopy or visits to the emergency department (ED)/urgent care for asthma in Puerto Rican children. This was a cross-sectional study of 317 children aged 6 to 14 years with (cases, n = 160) and without (control subjects, n = 157) asthma in San Juan, Puerto Rico. Our primary outcomes were the number of positive skin tests to allergens (range, 0-15) and (in cases only) having had at least one visit to the ED/urgent care for asthma in the prior year. Levels of glucan, endotoxin, peptidoglycan, and five allergens (Der p 1, Bla g 2, Fel d 1, Can f 1, and Mus m 1) were measured in samples of house dust. Linear or logistic regression was used for the multivariate analysis. In a multivariate analysis adjusting for case-control status, mouse allergen, and other covariates, children exposed to glucan levels in the second and third quartiles had approximately two more positive skin tests than those in the lowest quartile (P < 0.01 in both instances). Among children with asthma, exposure to the highest quartile of glucan was associated with nearly ninefold greater odds of one or more visits to the ED/urgent care for asthma (95% confidence interval for adjusted odds ratio, 2.7-28.4; P < 0.001). Our results suggest that indoor fungal exposure leads to an increased degree of atopy and visits to the ED/urgent care for asthma in Puerto Rican children.

  15. Fungal Exposure, Atopy, and Asthma Exacerbations in Puerto Rican Children

    PubMed Central

    Blatter, Joshua; Forno, Erick; Brehm, John; Acosta-Pérez, Edna; Alvarez, María; Colón-Semidey, Angel; Thorne, Peter S.; Metwali, Nervana; Canino, Glorisa

    2014-01-01

    Background: Glucan is a component of the fungal cell wall that is used as a marker of fungal exposure. Little is known about indoor glucan, atopy, and asthma exacerbations among children living in tropical environments such as Puerto Rico. Our objective was to examine whether glucan exposure is associated with degree of atopy or visits to the emergency department (ED)/urgent care for asthma in Puerto Rican children. Methods: This was a cross-sectional study of 317 children aged 6 to 14 years with (cases, n = 160) and without (control subjects, n = 157) asthma in San Juan, Puerto Rico. Our primary outcomes were the number of positive skin tests to allergens (range, 0–15) and (in cases only) having had at least one visit to the ED/urgent care for asthma in the prior year. Levels of glucan, endotoxin, peptidoglycan, and five allergens (Der p 1, Bla g 2, Fel d 1, Can f 1, and Mus m 1) were measured in samples of house dust. Linear or logistic regression was used for the multivariate analysis. Measurements and Main Results: In a multivariate analysis adjusting for case-control status, mouse allergen, and other covariates, children exposed to glucan levels in the second and third quartiles had approximately two more positive skin tests than those in the lowest quartile (P < 0.01 in both instances). Among children with asthma, exposure to the highest quartile of glucan was associated with nearly ninefold greater odds of one or more visits to the ED/urgent care for asthma (95% confidence interval for adjusted odds ratio, 2.7–28.4; P < 0.001). Conclusions: Our results suggest that indoor fungal exposure leads to an increased degree of atopy and visits to the ED/urgent care for asthma in Puerto Rican children. PMID:24915164

  16. Recombinant Allergens in Structural Biology, Diagnosis, and Immunotherapy

    PubMed Central

    Tscheppe, Angelika; Breiteneder, Heimo

    2017-01-01

    The years 1988–1995 witnessed the beginning of allergen cloning and the generation of recombinant allergens, which opened up new avenues for the diagnosis and research of human allergic diseases. Most crystal and solution structures of allergens have been obtained using recombinant allergens. Structural information on allergens allows insights into their evolutionary biology, illustrates clinically observed cross-reactivities, and makes the design of hypoallergenic derivatives for allergy vaccines possible. Recombinant allergens are widely used in molecule-based allergy diagnosis such as protein microarrays or suspension arrays. Recombinant technologies have been used to produce well-characterized, noncontaminated vaccine components with known biological activities including a variety of allergen derivatives with reduced IgE reactivity. Such recombinant hypoallergens as well as wild-type recombinant allergens have been used successfully in several immunotherapy trials for more than a decade to treat birch and grass pollen allergy. As a more recent application, the development of antibody repertoires directed against conformational epitopes during immunotherapy has been monitored by recombinant allergen chimeras. Although much progress has been made, the number and quality of recombinant allergens will undoubtedly increase and keep improving our knowledge in basic scientific investigations, diagnosis, and therapy of human allergic diseases. PMID:28467993

  17. [Ethanol changes sensitivity of Kupffer cells to endotoxin].

    PubMed

    Yamashina, Shunhei; Ikejima, Kenichi; Enomoto, Nobuyuki; Takei, Yoshiyuki; Sato, Nobuhiro

    2003-10-01

    Gut-derived endotoxin plays an important role in alcoholic liver injury. Intestinal sterilization with antibiotics (polymyxin B and neomycin) or inactivation of Kupffer cells with gadolinium chloride can prevent early alcohol-induced liver injury in the Tsukamoto-French model. Although short-term administration of alcohol enhances endotoxin hepatotoxicity, a majority of studies report that short-term ethanol inactivates Kupffer cells. It is therefore paradoxical that Kupffer cells are involved in alcoholic liver injury based on in vivo data with gadolinium chloride and antibiotics, yet ethanol blunts activation of isolated Kupffer cells. Accordingly, this review focuses on understanding this paradox by studying the temporal effect of ethanol in vivo on the response of subsequently isolated Kupffer cells. Mice were given ethanol intragastrically, and LPS was injected later. One hour after ethanol treatment, serum transaminases after LPS were 60% of control, while ethanol increased these parameters about 3-fold 21 hours after ethanol. Pretreatment with antibiotics blocked these effects of ethanol. Two hours after ethanol administration, the LPS-induced increases in intracellular calcium concentration and TNF alpha release by Kupffer cells was diminished by 50% of control, and these parameters were reciprocally enhanced two-fold at 24 hours. Sterilization of the gut with antibiotics blocked both effects of ethanol on intracellular calcium concentration and TNF alpha release. Twenty-four hours after ethanol, CD14 in Kupffer cells was elevated to about five-fold. In Kupffer cells from mice treated with ethanol 1 hour earlier, IRAK expression and activity and NF kappa B were decreased to 50-60% of control. In contrast, in Kupffer cells from mice treated with ethanol 21 hours earlier, LPS-induced TNF alpha production, expression and activity of IRAK were increased 1.5-fold over controls, while NF kappa B activation was elevated 3-fold. Kupffer cells isolated from rodents

  18. Endotoxins and other sepsis triggers.

    PubMed

    Opal, Steven M

    2010-01-01

    Endotoxin, or more accurately termed bacterial lipopolysaccharide (LPS), is recognized as the most potent microbial mediator implicated in the pathogenesis of sepsis and septic shock. Yet despite its discovery well over a century ago, the fundamental role of circulating endotoxin in the blood of most patients with septic shock remains enigmatic and a subject of considerable controversy. LPS is the most prominent 'alarm molecule' sensed by the host's early warning system of innate immunity presaging the threat of invasion of the internal milieu by Gram-negative bacterial pathogens. In small doses within a localized tissue space, LPS signaling is advantageous to the host in orchestrating an appropriate antimicrobial defense and bacterial clearance mechanisms. Conversely, the sudden release of large quantities of LPS into the bloodstream is clearly deleterious to the host, initiating the release of a dysregulated and potentially lethal array of inflammatory mediators and procoagulant factors in the systemic circulation. The massive host response to this single bacterial pattern recognition molecule is sufficient to generate diffuse endothelial injury, tissue hypoperfusion, disseminated intravascular coagulation and refractory shock. Numerous attempts to block endotoxin activity in clinical trials with septic patients have met with inconsistent and largely negative results. Yet the groundbreaking discoveries within the past decade into the precise molecular basis for LPS-mediated cellular activation and tissue injury has rekindled optimism that a new generation of therapies that specifically disrupt LPS signaling might succeed. Other microbial mediators found in Gram-positive bacterial and viral and fungal pathogens are now appreciated to activate many of the same host defense networks induced by LPS. This information is providing novel interventions in the continuing effots to improve the care of septic patients. Copyright 2010 S. Karger AG, Basel.

  19. Endotoxin levels correlate positively with a sedentary lifestyle and negatively with highly trained subjects

    PubMed Central

    2010-01-01

    Introduction A sedentary lifestyle increases the risk of developing cardiovascular disease, obesity, and diabetes. This phenomenon is supported by recent studies suggesting a chronic, low-grade inflammation status. Endotoxin derived from gut flora may be key to the development of inflammation by stimulating the secretion of inflammatory factors. This study aimed to examine plasma inflammatory markers and endotoxin levels in individuals with a sedentary lifestyle and/or in highly trained subjects at rest. Methods: Fourteen male subjects (sedentary lifestyle n = 7; highly trained subjects n = 7) were recruited. Blood samples were collected after an overnight fast (~12 h). The plasmatic endotoxin, plasminogen activator inhibitor type-1 (PAI-1), monocyte chemotactic protein-1 (MCP1), ICAM/CD54, VCAM/CD106 and lipid profile levels were determined. Results Endotoxinemia was lower in the highly trained subject group relative to the sedentary subjects (p < 0.002). In addition, we observed a positive correlation between endotoxin and PAI-1 (r = 0.85, p < 0.0001), endotoxin and total cholesterol (r = 0.65; p < 0.01), endotoxin and LDL-c (r = 0.55; p < 0.049) and endotoxin and TG levels (r = 0.90; p < 0.0001). The plasma levels of MCP-1, ICAM/CD54 and VCAM/CD106 did not differ. Conclusion These results indicate that a lifestyle associated with high-intensity and high-volume exercise induces favorable changes in chronic low-grade inflammation markers and may reduce the risk for diseases such as obesity, diabetes and cardiovascular diseases. PMID:20684772

  20. Plasma endotoxin activity in kangaroos with oral necrobacillosis (lumpy jaw disease) using an automated handheld testing system

    PubMed Central

    SOTOHIRA, Yukari; SUZUKI, Kazuyuki; SASAKI, Haruka; SANO, Tadashi; TSUCHIYA, Masakazu; SUZUKI, Yohko; SHIMAMORI, Toshio; TSUKANO, Kenji; SATO, Ayano; YOKOTA, Hiroshi; ASAKAWA, Mitsuhiko

    2016-01-01

    The aim of the present study was to evaluate the reliability and effectiveness of directly determining endotoxin activity in plasma samples from kangaroos with lumpy jaw disease (LJD, n=15) and healthy controls (n=12). Prior to the present study, the ability of the commercially available automated handheld portable test system (PTSTM) to detect endotoxin activity in kangaroo plasma was compared with that of the traditional LAL-kinetic turbidimetric (KT) assay. Plasma samples, which were obtained from endotoxin-challenged cattle, were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. The performance of the PTSTM was not significantly different from that of the traditional LAL-based assay. The data obtained using PTSTM correlated with those using KT (r2=0.963, P<0.001). These findings indicated that the PTSTM is applicable as a simplified system to assess endotoxin activity in macropods. In the present study, we demonstrated the diagnostic value of plasma endotoxin activity in kangaroos with systemic inflammation caused by oral necrobacillosis and identified plasma endotoxin activity as a sensitive marker of systemic inflammation in kangaroos with LJD. Based on ROC curves, we proposed a diagnostic cut-off point for endotoxin activity of >0.22 EU/ml for the identification of LJD. Our results indicate that the assessment of plasma endotoxin activity is a promising diagnostic tool for determining the outcome of LJD in captive macropods. PMID:26902804

  1. Plasma endotoxin activity in kangaroos with oral necrobacillosis (lumpy jaw disease) using an automated handheld testing system.

    PubMed

    Sotohira, Yukari; Suzuki, Kazuyuki; Sasaki, Haruka; Sano, Tadashi; Tsuchiya, Masakazu; Suzuki, Yohko; Shimamori, Toshio; Tsukano, Kenji; Sato, Ayano; Yokota, Hiroshi; Asakawa, Mitsuhiko

    2016-07-01

    The aim of the present study was to evaluate the reliability and effectiveness of directly determining endotoxin activity in plasma samples from kangaroos with lumpy jaw disease (LJD, n=15) and healthy controls (n=12). Prior to the present study, the ability of the commercially available automated handheld portable test system (PTS(TM)) to detect endotoxin activity in kangaroo plasma was compared with that of the traditional LAL-kinetic turbidimetric (KT) assay. Plasma samples, which were obtained from endotoxin-challenged cattle, were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. The performance of the PTS(TM) was not significantly different from that of the traditional LAL-based assay. The data obtained using PTS(TM) correlated with those using KT (r(2)=0.963, P<0.001). These findings indicated that the PTS(TM) is applicable as a simplified system to assess endotoxin activity in macropods. In the present study, we demonstrated the diagnostic value of plasma endotoxin activity in kangaroos with systemic inflammation caused by oral necrobacillosis and identified plasma endotoxin activity as a sensitive marker of systemic inflammation in kangaroos with LJD. Based on ROC curves, we proposed a diagnostic cut-off point for endotoxin activity of >0.22 EU/ml for the identification of LJD. Our results indicate that the assessment of plasma endotoxin activity is a promising diagnostic tool for determining the outcome of LJD in captive macropods.

  2. Obesity Increases Sensitivity to Endotoxin Liver Injury: Implications for the Pathogenesis of Steatohepatitis

    NASA Astrophysics Data System (ADS)

    Yang, Shi Qi; Zhi Lin, Hui; Lane, M. Daniel; Clemens, Mark; Diehl, Anna Mae

    1997-03-01

    Genetically obese fatty/fatty rats and obese/obese mice exhibit increased sensitivity to endotoxin hepatotoxicity, quickly developing steatohepatitis after exposure to low doses of lipopolysaccharide (LPS). Among obese animals, females are more sensitive to endotoxin liver injury than males. LPS induction of tumor necrosis factor α (TNFα ), the proven affecter of endotoxin liver injury, is no greater in the livers, white adipose tissues, or sera of obese animals than in those of lean controls. Indeed, the lowest serum concentrations of TNF occur in female obese rodents, which exhibit the most endotoxin-induced liver injury. Several cytokines that modulate the biological activity of TNF are regulated abnormally in the livers of obese animals. After exposure to LPS, mRNA of interferon γ , which sensitizes hepatocytes to TNF toxicity, is overexpressed, and mRNA levels of interleukin 10, a TNF inhibitor, are decreased. The phagocytic activity of liver macrophages and the hepatic expression of a gene encoding a macrophage-specific receptor are also decreased in obesity. This new animal model of obesity-associated liver disease demonstrates that hepatic macrophage dysfunction occurs in obesity and suggests that this might promote steatohepatitis by sensitizing hepatocytes to endotoxin.

  3. Endotoxin of Escherichia coli and permeability of the mammary glands of goats

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

    Lengemann, F.W.; Pitzrick, M.

    Serial collections of milk were used to determine where in the mammary gland endotoxin of Escherichia coli was effective in altering the transfer of selected milk components into blood and blood components into milk. Lactating goats had half the gland infused with 1 ..mu..g of endotoxin and the other half served as a control. Sodium-24 and /sup 42/K or (/sup 14/C) lactose were included with /sup 141/Ce in the infusate in some experiments, whereas in others /sup 99m/Tc-labelled albumin or /sup 24/Na and /sup 42/K were given intravenously 2 h after the endotoxin infusion. Milk was collected 3 h aftermore » endotoxin infusion. Endotoxin increased the loss of /sup 24/Na, /sup 42/K, and (/sup 14/C) lactose from the mammary gland and increased the transfer of /sup 24/Na and /sup 99m/Tc-albumin into the gland. The transfer in of /sup 42/K was reduced compared with control halves. Movement of stable Na and K was in accord with the movement of the /sup 24/Na and /sup 42/K. Endotoxin was effective in all parts of the gland but particularly from the mid-portion upward to the alveoli. For the control halves there was evidence that some /sup 24/Na and /sup 42/K crossed the ductal or cisternal epithelium into blood outside of the alveoli, whereas only /sup 42/K provided evidence for transfer from blood to milk in these same regions. There was no demonstrable transfer of lactose and albumin in regions other than the alveoli.« less

  4. Origin and Functional Prediction of Pollen Allergens in Plants.

    PubMed

    Chen, Miaolin; Xu, Jie; Devis, Deborah; Shi, Jianxin; Ren, Kang; Searle, Iain; Zhang, Dabing

    2016-09-01

    Pollen allergies have long been a major pandemic health problem for human. However, the evolutionary events and biological function of pollen allergens in plants remain largely unknown. Here, we report the genome-wide prediction of pollen allergens and their biological function in the dicotyledonous model plant Arabidopsis (Arabidopsis thaliana) and the monocotyledonous model plant rice (Oryza sativa). In total, 145 and 107 pollen allergens were predicted from rice and Arabidopsis, respectively. These pollen allergens are putatively involved in stress responses and metabolic processes such as cell wall metabolism during pollen development. Interestingly, these putative pollen allergen genes were derived from large gene families and became diversified during evolution. Sequence analysis across 25 plant species from green alga to angiosperms suggest that about 40% of putative pollen allergenic proteins existed in both lower and higher plants, while other allergens emerged during evolution. Although a high proportion of gene duplication has been observed among allergen-coding genes, our data show that these genes might have undergone purifying selection during evolution. We also observed that epitopes of an allergen might have a biological function, as revealed by comprehensive analysis of two known allergens, expansin and profilin. This implies a crucial role of conserved amino acid residues in both in planta biological function and allergenicity. Finally, a model explaining how pollen allergens were generated and maintained in plants is proposed. Prediction and systematic analysis of pollen allergens in model plants suggest that pollen allergens were evolved by gene duplication and then functional specification. This study provides insight into the phylogenetic and evolutionary scenario of pollen allergens that will be helpful to future characterization and epitope screening of pollen allergens. © 2016 American Society of Plant Biologists. All rights reserved.

  5. Scientific advancement of novel protein allergenicity evaluation: an overview of work from the HESI Protein Allergenicity Technical Committee (2000-2008).

    PubMed

    Thomas, Karluss; MacIntosh, Sue; Bannon, Gary; Herouet-Guicheney, Corinne; Holsapple, Michael; Ladics, Gregory; McClain, Scott; Vieths, Stefan; Woolhiser, Michael; Privalle, Laura

    2009-06-01

    The safety assessment of genetically modified crops includes the evaluation for potential allergenicity. The current 'state-of-the-science' utilizes a weight of evidence approach, as outlined by the Codex Alimentarius commission (Alinorm 03/34 A), recognizing no single endpoint is predictive of the allergenic potential of a novel protein. This approach evaluates: whether the gene source is allergenic, sequence similarity to known allergens, and protein resistance to pepsin in vitro. If concerns are identified, serological studies may be necessary to determine if a protein has IgE binding similar to known allergens. Since there was a lack of standardized/validated methods to conduct the allergenicity assessment, a committee was assembled under the International Life Sciences Institute Health and Environmental Sciences Institute to address this issue. Over the last eight years, the Protein Allergenicity Technical Committee has convened workshops and symposia with allergy experts and government authorities to refine methods that underpin the assessment for potential protein allergenicity. This publication outlines this ongoing effort, summarizing workshops and formal meetings, referencing publications, and highlighting outreach activities. The purpose is to (1) outline 'the state-of-the-science' in predicting protein allergenicity in the context of current international recommendations for novel protein safety assessment, and (2) identify approaches that can be improved and future research needs.

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

    PubMed

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

    2007-08-01

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

  7. Population disparities in asthma.

    PubMed

    Gold, Diane R; Wright, Rosalind

    2005-01-01

    The prevalence of asthma in the United States is higher than in many other countries in the world. Asthma, the most common chronic disease of childhood in the United States, disproportionately burdens many socioeconomically disadvantaged urban communities. In this review we discuss hypotheses for between-country disparities in asthma prevalence, including differences in "hygiene" (e.g., family size, use of day care, early-life respiratory infection exposures, endotoxin and other farm-related exposures, microbial colonization of the infant bowel, exposure to parasites, and exposure to large domestic animal sources of allergen), diet, traffic pollution, and cigarette smoking. We present data on socioeconomic and ethnic disparities in asthma prevalence and morbidity in the United States and discuss environmental factors contributing to asthma disparities (e.g., housing conditions, indoor environmental exposures including allergens, traffic air pollution, disparities in treatment and access to care, and cigarette smoking). We discuss environmental influences on somatic growth (low birth weight, prematurity, and obesity) and their relevance to asthma disparities. The relevance of the hygiene hypothesis to the U.S. urban situation is reviewed. Finally, we discuss community-level factors contributing to asthma disparities.

  8. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes

    PubMed Central

    Leong, Misha; Bayless, Keith M.; Malow, Tara L.F.; Dunn, Robert R.; Trautwein, Michelle D.

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32–211 morphospecies, and 24–128 distinct arthropod families per house. The majority of this indoor diversity (73%) was made up of true flies (Diptera), spiders (Araneae), beetles (Coleoptera), and wasps and kin (Hymenoptera, especially ants: Formicidae). Much of the arthropod diversity within houses did not consist of synanthropic species, but instead included arthropods that were filtered from the surrounding landscape. As such, common pest species were found less frequently than benign species. Some of the most frequently found arthropods in houses, such as gall midges (Cecidomyiidae) and book lice (Liposcelididae), are unfamiliar to the general public despite their ubiquity. These findings present a new understanding of the diversity, prevalence, and distribution of the arthropods in our daily lives. Considering their impact as household pests, disease vectors, generators of allergens, and facilitators of the indoor microbiome, advancing our knowledge of the ecology and evolution of arthropods in homes has major economic and human health implications. PMID:26819844

  9. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes.

    PubMed

    Bertone, Matthew A; Leong, Misha; Bayless, Keith M; Malow, Tara L F; Dunn, Robert R; Trautwein, Michelle D

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32-211 morphospecies, and 24-128 distinct arthropod families per house. The majority of this indoor diversity (73%) was made up of true flies (Diptera), spiders (Araneae), beetles (Coleoptera), and wasps and kin (Hymenoptera, especially ants: Formicidae). Much of the arthropod diversity within houses did not consist of synanthropic species, but instead included arthropods that were filtered from the surrounding landscape. As such, common pest species were found less frequently than benign species. Some of the most frequently found arthropods in houses, such as gall midges (Cecidomyiidae) and book lice (Liposcelididae), are unfamiliar to the general public despite their ubiquity. These findings present a new understanding of the diversity, prevalence, and distribution of the arthropods in our daily lives. Considering their impact as household pests, disease vectors, generators of allergens, and facilitators of the indoor microbiome, advancing our knowledge of the ecology and evolution of arthropods in homes has major economic and human health implications.

  10. Dustborne Alternaria alternata antigens in U.S. homes: Results from the National Survey of Lead and Allergens in Housing

    PubMed Central

    Salo, Päivi M.; Yin, Ming; Arbes, Samuel J.; Cohn, Richard D.; Sever, Michelle; Muilenberg, Michael; Burge, Harriet A.; London, Stephanie J.; Zeldin, Darryl C.

    2005-01-01

    Background: Alternaria alternata is one of the most common fungi associated with allergic disease. However, Alternaria exposure in indoor environments is not well characterized. Objective: The primary goals of this study were to examine the prevalence of Alternaria exposure and identify independent predictors of Alternaria antigen concentrations in U.S. homes. Methods: Data for this cross-sectional study were obtained from the National Survey of Lead and Allergens in Housing. A nationally representative sample of 831 housing units in 75 different locations throughout the U.S. completed the survey. Information on housing and household characteristics was obtained by questionnaire and environmental assessments. Concentrations of Alternaria antigens in dust collected from various indoor sites were assessed with a polyclonal anti-Alternaria antibody assay. Results: Alternaria antigens were detected in most (95-99%) of the dust samples. The geometric mean concentration, reflecting the average Alternaria concentration in homes, was 4.88 μg/g (SE=0.13 μg/g). In the multivariable linear regression analysis, the age of the housing unit, geographic region, urbanization, poverty, family race, observed mold and moisture problems, use of dehumidifier, and presence of cats and dogs were independent predictors of Alternaria antigen concentrations. Less frequent cleaning and smoking indoors also contributed to higher Alternaria antigen levels in homes. Conclusion: Exposure to Alternaria alternata antigens in U.S. homes is common. Antigen levels in homes are not only influenced by regional factors but also by residential characteristics. Preventing mold and moisture problems, avoiding smoking indoors, and regular household cleaning may help reduce exposure to Alternaria antigens indoors. PMID:16159634

  11. Fiber-optic Fourier transform infrared (FO-FTIR) spectroscopy for detecting endotoxin contamination in ophthalmic viscosurgical devices (OVDS) (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hassan, Moinuddin; Ilev, Ilko

    2016-03-01

    Ophthalmic Viscosurgical Devices (OVDs) in clinical setting are a major health risk factor for potential endotoxin contamination in the eye, due to their extensive applications in cataract surgery for space creation, stabilization and protection of intraocular tissue and intraocular lens (IOL) during implantation. Endotoxin contamination of OVDs is implicated in toxic anterior syndrome (TASS), a severe complication of cataract surgery that leads to intraocular damage and even blindness. Current standard methods for endotoxin contamination detection utilize rabbit assay or Limulus amoebocyte lysate (LAL) assays. These endotoxin detection strategies are extremely difficult for gel-like type devices such as OVDs. To overcome the endotoxin detection limitations in OVDs, we have developed an alternative optical detection methodology for label-free and real-time sensing of bacterial endotoxin in OVDs, based on fiber-optic Fourier transform infrared (FO-FTIR) transmission spectrometry in the mid-IR spectral range from 2.5 micron to 12 micron. Endotoxin contaminated OVD test samples were prepared by serial dilutions of endotoxins on OVDs. The major results of this study revealed two salient spectral peak shifts (in the regions 2925 to 2890 cm^-1 and 1125 to 1100 cm^-1), which are associated with endotoxin in OVDs. In addition, FO-FTIR experimental results processed using a multivariate analysis confirmed the observed specific peak shifts associated with endotoxin contamination in OVDs. Thus, employing the FO-FTIR sensing methodology integrated with a multivariate analysis could potentially be used as an alternative endotoxin detection technique in OVD.

  12. A protocol for a systematic review to identify allergenic tree nuts and the molecules responsible for their allergenic properties.

    PubMed

    Javed, Bushra; Padfield, Philip; Sperrin, Matthew; Simpson, Angela; Mills, E N Clare

    2017-08-01

    Food regulations require that tree nuts and derived ingredients are included on food labels in order to help individuals with IgE-mediated allergies to avoid them. However, there is no consensus regarding which tree nut species should be included in this definition and specified on food labels. Allergen detection methods used for monitoring foods target allergen molecules, but it not clear which are the most relevant molecules to choose. A modified population-exposure-comparators-outcome (PECO) approach has been developed to systematically review the evidence regarding (1) which allergenic tree nuts should be included in food allergen labelling lists and (2) which are the clinically relevant allergens which should be used as analytical targets. A search strategy and criteria against which the evidence will be evaluated have been developed. The resulting evidence will be used to rank tree nuts with regards their ability to cause IgE-mediated allergies, and allergen molecules regarding their capacity to elicit an allergic reaction. The results of the systematic review will enable risk assessors and managers to identify tree nut species that should be included in food allergen labelling lists and ensure analytical methods for determination of allergens in foods are targeting appropriate molecules. Copyright © 2017. Published by Elsevier Ltd.

  13. Rabbit intraocular reactivity to endotoxin measured by slit-lamp biomicroscopy and laser flare photometry.

    PubMed

    Nussenblatt, Robert B; Calogero, Don; Buchen, Shelley Y; Leder, Henry A; Goodkin, Margot; Eydelman, Malvina B

    2012-07-01

    To evaluate the ocular reactivity of the rabbit to an intracameral injection of a dispersive ophthalmic viscosurgical device (OVD) containing various levels of bacterial endotoxin using slit-lamp biomicroscopy and laser flare photometry. Experimental, randomized, masked animal study. Thirty Dutch-Belted rabbits. The rabbits were randomized into 6 groups to receive 0.05 ml of a hydroxypropyl methylcellulose-based dispersive OVD to which had been added one of 5 different doses of bacterial endotoxin ranging from 0.02 to 1.4 endotoxin units (EUs) or a vehicle control to both eyes. The eyes were evaluated for anterior segment inflammation at baseline and 3, 6, 9, 24, 48, and 72 hours after injection using slit-lamp biomicroscopy and laser flare photometry. Corneal clarity and anterior chamber (AC) inflammation. All the corneas remained clear throughout the study. Anterior chamber cells were seen at 6, 9, and 24 hours in 60% to 100% of the eyes intracamerally injected with endotoxin-containing OVD, and the response declined rapidly after 24 hours. A dose-response effect was seen between the concentration of endotoxin and the AC cell response. The aqueous flare response in eyes injected with the 2 highest doses of endotoxin was significantly greater (P<0.05) than that of controls. The amounts of fibrin observed in the AC were random, with no apparent dose-response effect seen. The flare values as obtained by laser flare photometry were consistent with the slit-lamp biomicroscopy flare findings up to grade 3+. However, the increase in laser flare value seemed to level off in eyes with more than 3+ flare. Neither measure of flare correlated with endotoxin level. Among the parameters evaluated in this study, the AC cell response, evaluated by slit-lamp biomicroscopy and graded using a standard grading system, was found to be the most reliable indicator of the amount of endotoxin in the dispersive OVD. The use of laser flare photometry alone does not seem to be useful in

  14. Indoor risk factors for cough and their relation to wheeze and sensitization in Chilean young adults.

    PubMed

    Potts, James F; Rona, Roberto J; Oyarzun, Manuel J; Amigo, Hugo; Bustos, Patricia

    2008-04-01

    We assessed the effects of indoor risk factors, including smoking, on different types of cough and on cough and wheeze in combination. Our sample was composed of 1232 men and women residing in a semirural area of Chile. We used a standardized questionnaire, sensitization to 8 allergens, and bronchial hyperresponsiveness to methacholine to assess cough and wheeze characteristics. Information was gathered on dampness, mold, ventilation, heating, housing quality, smoking, and environmental tobacco smoke exposure. Most exposures were associated with cough alone or cough in combination with wheeze. Smoking, past smoking, and environmental tobacco smoke exposure were strongly associated with dry cough and wheeze. The use of coal for heating was associated with dry cough. Leaks, mold, and lack of kitchen ventilation were associated with cough and wheeze. Nocturnal cough and productive cough were associated with specific types of sensitization, but dry cough was not. Productive cough was associated with hyperresponsiveness to methacholine. Several different types of indoor exposures, including environmental tobacco smoke exposure, are important contributors to morbidity associated with cough and wheeze. A vigorous preventive strategy designed to lower exposures to indoor risk factors would lower rates of respiratory morbidity.

  15. Indoor risk factors for cough and their relation to wheeze and sensitization in Chilean young adults

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

    Potts, J.F.; Rona, R.J.; Oyarzun, M.J.

    2008-04-15

    We assessed the effects of indoor risk factors, including smoking, on different types of cough and on cough and wheeze in combination. Our sample was composed of 1232 men and women residing in a semi-rural area of Chile. We used a standardized questionnaire, sensitization to 8 allergens, and bronchial hyperresponsiveness to methacholine to assess cough and wheeze characteristics. Information was gathered on dampness, mold, ventilation, heating, housing quality, smoking, and environmental tobacco smoke exposure. Most exposures were associated with cough alone or cough in combination with wheeze. Smoking, past smoking, and environmental tobacco smoke exposure were strongly associated with drymore » cough and wheeze. The use of coal for heating was associated with dry cough. Leaks, mold, and lack of kitchen ventilation were associated with cough and wheeze. Nocturnal cough and productive cough were associated with specific types of sensitization, but dry cough was not. Productive cough was associated with hyperresponsiveness to methacholine. Several different types of indoor exposures, including environmental tobacco smoke exposure, are important contributors to morbidity associated with cough and wheeze. A vigorous preventive strategy designed to lower exposures to indoor risk factors would lower rates of respiratory morbidity.« less

  16. Consumer preferences for food allergen labeling.

    PubMed

    Marra, Carlo A; Harvard, Stephanie; Grubisic, Maja; Galo, Jessica; Clarke, Ann; Elliott, Susan; Lynd, Larry D

    2017-01-01

    Food allergen labeling is an important tool to reduce risk of exposure and prevent anaphylaxis for individuals with food allergies. Health Canada released a Canadian food allergen labeling regulation (2008) and subsequent update (2012) suggesting that research is needed to guide further iterations of the regulation to improve food allergen labeling and reduce risk of exposure. The primary objective of this study was to examine consumer preferences in food labeling for allergy avoidance and anaphylaxis prevention. A secondary objective was to identify whether different subgroups within the consumer population emerged. A discrete choice experiment using a fractional factorial design divided into ten different versions with 18 choice-sets per version was developed to examine consumer preferences for different attributes of food labeling. Three distinct subgroups of Canadian consumers with different allergen considerations and food allergen labeling needs were identified. Overall, preferences for standardized precautionary and safety symbols at little or no increased cost emerged. While three distinct groups with different preferences were identified, in general the results revealed that the current Canadian food allergen labeling regulation can be improved by enforcing the use of standardized precautionary and safety symbols and educating the public on the use of these symbols.

  17. Characterization of Cannabis sativa allergens.

    PubMed

    Nayak, Ajay P; Green, Brett J; Sussman, Gordon; Berlin, Noam; Lata, Hemant; Chandra, Suman; ElSohly, Mahmoud A; Hettick, Justin M; Beezhold, Donald H

    2013-07-01

    Allergic sensitization to Cannabis sativa is rarely reported, but the increasing consumption of marijuana has resulted in an increase in the number of individuals who become sensitized. To date, little is known about the causal allergens associated with C sativa. To characterize marijuana allergens in different components of the C sativa plant using serum IgE from marijuana sensitized patients. Serum samples from 23 patients with a positive skin prick test result to a crude C sativa extract were evaluated. IgE reactivity was variable between patients and C sativa extracts. IgE reactivity to C sativa proteins in Western blots was heterogeneous and ranged from 10 to 70 kDa. Putative allergens derived from 2-dimensional gels were identified. Prominent IgE reactive bands included a 23-kDa oxygen-evolving enhancer protein 2 and a 50-kDa protein identified to be the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase. Additional proteins were identified in the proteomic analysis, including those from adenosine triphosphate synthase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, and luminal binding protein (heat shock protein 70), suggesting these proteins are potential allergens. Deglycosylation studies helped refine protein allergen identification and demonstrated significant IgE antibodies against plant oligosaccharides that could help explain cross-reactivity. Identification and characterization of allergens from C sativa may be helpful in further understanding allergic sensitization to this plant species. Copyright © 2013 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  18. Allergen Sensitization Pattern by Sex: A Cluster Analysis in Korea.

    PubMed

    Ohn, Jungyoon; Paik, Seung Hwan; Doh, Eun Jin; Park, Hyun-Sun; Yoon, Hyun-Sun; Cho, Soyun

    2017-12-01

    Allergens tend to sensitize simultaneously. Etiology of this phenomenon has been suggested to be allergen cross-reactivity or concurrent exposure. However, little is known about specific allergen sensitization patterns. To investigate the allergen sensitization characteristics according to gender. Multiple allergen simultaneous test (MAST) is widely used as a screening tool for detecting allergen sensitization in dermatologic clinics. We retrospectively reviewed the medical records of patients with MAST results between 2008 and 2014 in our Department of Dermatology. A cluster analysis was performed to elucidate the allergen-specific immunoglobulin (Ig)E cluster pattern. The results of MAST (39 allergen-specific IgEs) from 4,360 cases were analyzed. By cluster analysis, 39items were grouped into 8 clusters. Each cluster had characteristic features. When compared with female, the male group tended to be sensitized more frequently to all tested allergens, except for fungus allergens cluster. The cluster and comparative analysis results demonstrate that the allergen sensitization is clustered, manifesting allergen similarity or co-exposure. Only the fungus cluster allergens tend to sensitize female group more frequently than male group.

  19. Crystal structure of peanut (Arachis hypogaea) allergen Ara h 5

    USDA-ARS?s Scientific Manuscript database

    Profilins from numerous species are known to be allergens, including food allergens, such as peanut (Arachis hypogaea) allergen Ara h 5, and pollen allergens, such as birch allergen Bet v 2. Patients with pollen allergy can also cross-react to peanut. Structural characterization of allergens will al...

  20. Endotoxin as a cause of aseptic meningitis after radionuclide cisternography

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

    Cooper, J.F.; Harbert, J.C.

    1975-09-01

    The role of pyrogens in aseptic meningitis after radionuclide cisternography was studied by means of the Limulus test, a sensitive detector of endotoxin. During a 15-month period, 39 reactions associated with cisternography were reported. Ten samples of specific lots of the radioactive drugs implicated in 20 of these reactions were tested and all reacted strongly positive to the Limulus test. The less sensitive rabbit pyrogen test was negative for these preparations when tested on a dose-per-weight basis. Our findings apparently provide clinical evidence for the observation made in animals that endotoxin is at least 1,000 times more toxic intrathecally thanmore » intravenously. The data implicate endotoxin contamination as a cause of adverse reactions to radionuclide cisternography. We conclude that the USP pyrogen test is insufficiently sensitive for intrathecal injectables and should be supplemented by the Limulus test. (auth)« less

  1. Endotoxin Detection in Pharmaceuticals and Medical Devices with Kinetic-QCL, a Kinetic-Quantitative Chromogenic Limulus Amebocyte Lysate Assay.

    PubMed

    Berzofsky, Ronald N.

    1995-01-01

    The observation that endotoxin caused gelation in extracts of Limulus amebocytes has been expanded to the development of an in vitro kinetic, quantitative chromogenic LAL assay (Kinetic-QCL) for the detection of endotoxin in aqueous fluids. Within the last 15 years, the use of Limulus amebocyte lysate to detect and control the presence of pyrogenic substances in pharmaceuticals and medical devices has gained wide international acceptance. Both the United States and European Pharmacopoeias contain descriptions of and requirements for the LAL Bacterial Endotoxin Test. Both pharmacopoeias have begun to remove the rabbit pyrogen test requirement in a majority of drug monographs and have substituted endotoxin limits to be determined by LAL. The use of LAL has proved invaluable in controlling the level of endotoxin in finished product. The endotoxin contribution of raw materials and packaging material can be monitored as well. In-process testing at critical production steps can identify additional sources of endotoxin contamination, and depyrogenation processes can be validated by quantitating the degradation of endotoxin challenges. The speed, reproducibility, sensitivity, and economics of the Kinetic-QCL assay, in conjunction with the ppropriate equipment and software, over both the in vivo rabbit pyrogen test and the more traditional LAL gel-clot assay allow a more in-depth approach to the control of endotoxin in pharmaceuticals and medical devices.

  2. Cotton dust and endotoxin exposure-response relationships in cotton textile workers

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

    Kennedy, S.M.; Christiani, D.C.; Eisen, E.A.

    Endotoxin exposure has been implicated in the etiology of lung disease in cotton workers. We investigated this potential relationship in 443 cotton workers from 2 factories in Shanghai and 439 control subjects from a nearby silk mill. A respiratory questionnaire was administered and pre- and postshift forced expiratory volume (FVC) and flow in one second (FEV1) were determined for each worker. Multiple area air samples were analyzed for total elutriated dust concentration (range: 0.15 to 2.5 mg/m3) and endotoxin (range: 0.002 to 0.55 microgram U.S. Reference Endotoxin/m3). The cotton worker population was stratified by current and cumulative dust or endotoxinmore » exposure. Groups were compared for FEV1, FVC, FEV1/FVC%, % change in FEV1 over the shift (delta FEV1%), and prevalences of chronic bronchitis and byssinosis, and linear and logistic regression models were constructed. No dose-response relationships were demonstrated comparing dust concentration to any pulmonary function or symptom variable. A dose-response trend was seen with the current endotoxin level and FEV1, delta FEV1%, and the prevalence of byssinosis and chronic bronchitis, except for the highest exposure level group in which a reversal of the trend was seen. The regression coefficients for current endotoxin exposure were significant (p less than 0.05) in the models for FEV1 and chronic bronchitis but not in the models for delta FEV1% (i.e., acute change in FEV1) or byssinosis prevalence. The coefficient for dust level was never significant in the models.« less

  3. Species-Specific Activation of TLR4 by Hypoacylated Endotoxins Governed by Residues 82 and 122 of MD-2

    PubMed Central

    Oblak, Alja; Jerala, Roman

    2014-01-01

    The Toll-like receptor 4/MD-2 receptor complex recognizes endotoxin, a Gram-negative bacterial cell envelope component. Recognition of the most potent hexaacylated form of endotoxin is mediated by the sixth acyl chain that protrudes from the MD-2 hydrophobic pocket and bridges TLR4/MD-2 to the neighboring TLR4 ectodomain, driving receptor dimerization via hydrophobic interactions. In hypoacylated endotoxins all acyl chains could be accommodated within the binding pocket of the human hMD-2. Nevertheless, tetra- and pentaacylated endotoxins activate the TLR4/MD-2 receptor of several species. We observed that amino acid residues 82 and 122, located at the entrance to the endotoxin binding site of MD-2, have major influence on the species-specific endotoxin recognition. We show that substitution of hMD-2 residue V82 with an amino acid residue with a bulkier hydrophobic side chain enables activation of TLR4/MD-2 by pentaacylated and tetraacylated endotoxins. Interaction of the lipid A phosphate group with the amino acid residue 122 of MD-2 facilitates the appropriate positioning of the hypoacylated endotoxin. Moreover, mouse TLR4 contributes to the agonistic effect of pentaacylated msbB endotoxin. We propose a molecular model that explains how the molecular differences between the murine or equine MD-2, which both have sufficiently large hydrophobic pockets to accommodate all five or four acyl chains, influence the positioning of endotoxin so that one of the acyl chains remains outside the pocket and enables hydrophobic interactions with TLR4, leading to receptor activation. PMID:25203747

  4. Species-specific activation of TLR4 by hypoacylated endotoxins governed by residues 82 and 122 of MD-2.

    PubMed

    Oblak, Alja; Jerala, Roman

    2014-01-01

    The Toll-like receptor 4/MD-2 receptor complex recognizes endotoxin, a Gram-negative bacterial cell envelope component. Recognition of the most potent hexaacylated form of endotoxin is mediated by the sixth acyl chain that protrudes from the MD-2 hydrophobic pocket and bridges TLR4/MD-2 to the neighboring TLR4 ectodomain, driving receptor dimerization via hydrophobic interactions. In hypoacylated endotoxins all acyl chains could be accommodated within the binding pocket of the human hMD-2. Nevertheless, tetra- and pentaacylated endotoxins activate the TLR4/MD-2 receptor of several species. We observed that amino acid residues 82 and 122, located at the entrance to the endotoxin binding site of MD-2, have major influence on the species-specific endotoxin recognition. We show that substitution of hMD-2 residue V82 with an amino acid residue with a bulkier hydrophobic side chain enables activation of TLR4/MD-2 by pentaacylated and tetraacylated endotoxins. Interaction of the lipid A phosphate group with the amino acid residue 122 of MD-2 facilitates the appropriate positioning of the hypoacylated endotoxin. Moreover, mouse TLR4 contributes to the agonistic effect of pentaacylated msbB endotoxin. We propose a molecular model that explains how the molecular differences between the murine or equine MD-2, which both have sufficiently large hydrophobic pockets to accommodate all five or four acyl chains, influence the positioning of endotoxin so that one of the acyl chains remains outside the pocket and enables hydrophobic interactions with TLR4, leading to receptor activation.

  5. Involvement of sympathetic nervous system and brown fat in endotoxin-induced fever in rats.

    PubMed

    Jepson, M M; Millward, D J; Rothwell, N J; Stock, M J

    1988-11-01

    The object of this study was to assess the role of brown adipose tissue (BAT) and the sympathetic nervous system in the rise in heat production associated with endotoxin-induced fever. Oxygen consumption (VO2) was found to be significantly increased (28%) over a 4-h period after two doses of endotoxin (Escherichia coli lipopolysaccharide, 0.3 mg/100 g body wt) given 24 h apart. Injection of a mixed beta-adrenoceptor antagonist (propranolol) reduced VO2 by 14% in endotoxin-treated rats, whereas the selective beta 1- (atenolol) or beta 2- (ICI 118551) antagonists suppressed VO2 by 10%. These drugs did not affect VO2 in control animals. BAT thermogenic activity assessed from measurements of in vitro mitochondrial guanosine 5'-diphosphate (GDP) binding was elevated by 54% in interscapular BAT and by 171% in other BAT depots. Surgical denervation of one lobe of the interscapular depot prevented these responses. Endotoxin failed to stimulate GDP binding in rats fed protein-deficient diets. This may have been because BAT thermogenic activity was already elevated in control rats fed these diets or because endotoxin caused a marked suppression of food intake in the protein-deficient animals. The results indicate that sympathetic activation of BAT is involved in the thermogenic responses to endotoxin and that these can be modified by dietary manipulation.

  6. Moderate exercise increases endotoxin concentration in hypoxia but not in normoxia: A controlled clinical trial.

    PubMed

    Machado, Paola; Caris, Aline; Santos, Samile; Silva, Edgar; Oyama, Lila; Tufik, Sergio; Santos, Ronaldo

    2017-01-01

    Hypoxia and high altitudes affect various organs, which impairs important physiological functions, such as a disruption of the intestinal barrier mediated by increased translocation of bacteria and increased circulating endotoxin levels. Physical exercise can alter endotoxin concentration in normoxia. The aim of this study is to evaluate the effects of moderate exercise on endotoxin concentration in normobaric hypoxia. Nine healthy male volunteers exercised on a treadmill for 60 minutes at an intensity of 50% VO2peak in normoxic or hypoxic conditions (4200 m). Blood was collected at rest, immediately after exercise and 1 hour after exercise to evaluate serum endotoxin levels. Under hypoxic exercise conditions, SaO2% saturation was lower after exercise compared with resting levels (P < 0.05) and returned to the resting level during recovery in normoxia (P < 0.05). Endotoxin concentration increased after exercise in hypoxia (P < 0.05); it remained high 1 hour after exercise in hypoxia compared with normoxia (P < 0.05) and was higher after exercise and recovery compared with resting levels (P < 0.05). HR was higher during exercise in relation basal in both conditions (P < 0.05) and RPR increase after 60 minutes in comparison to 20 minutes in hypoxia (P < 0.05). Moderate exercise performed in hypoxia equivalent to 4200 m increased endotoxin plasma concentration after exercise. One hour of rest in normoxic conditions was insufficient for the recovery of circulating endotoxins.

  7. Exposure to high endotoxin concentration increases wheezing prevalence among laboratory animal workers: a cross-sectional study.

    PubMed

    Freitas, Amanda Souza; Simoneti, Christian Silva; Ferraz, Erica; Bagatin, Ericson; Brandão, Izaira Tincani; Silva, Celio Lopes; Borges, Marcos Carvalho; Vianna, Elcio Oliveira

    2016-05-06

    Endotoxin from Gram-negative bacteria are found in different concentrations in dust and on the ground of laboratories dealing with small animals and animal houses. Cross-sectional study performed in workplaces of two universities. Dust samples were collected from laboratories and animal facilities housing rats, mice, guinea pigs, rabbits or hamsters and analyzed by the "Limulus amebocyte lysate" (LAL) method. We also sampled workplaces without animals. The concentrations of endotoxin detected in the workplaces were tested for association with wheezing in the last 12 months, asthma defined by self-reported diagnosis and asthma confirmed by bronchial hyperresponsiveness (BHR) to mannitol. Dust samples were obtained at 145 workplaces, 92 with exposure to animals and 53 with no exposure. Exposed group comprised 412 subjects and non-exposed group comprised 339 subjects. Animal-exposed workplaces had higher concentrations of endotoxin, median of 34.2 endotoxin units (EU) per mg of dust (interquartile range, 12.6-65.4), as compared to the non-exposed group, median of 10.2 EU/mg of dust (interquartile range, 2.6-22.2) (p < 0.001). The high concentration of endotoxin (above whole sample median, 20.4 EU/mg) was associated with increased wheezing prevalence (p < 0.001), i.e., 61 % of workers exposed to high endotoxin concentration reported wheezing in the last 12 months compared to 29 % of workers exposed to low endotoxin concentration. The concentration of endotoxin was not associated with asthma report or with BHR confirmed asthma. Exposure to endotoxin is associated with a higher prevalence of wheezing, but not with asthma as defined by the mannitol bronchial challenge test or by self-reported asthma. Preventive measures are necessary for these workers.

  8. Allergen-Specific Immunotherapies for Food Allergy

    PubMed Central

    Feuille, Elizabeth

    2018-01-01

    With rising prevalence of food allergy (FA), allergen-specific immunotherapy (AIT) for FA has become an active area of research in recent years. In AIT, incrementally increasing doses of inciting allergen are given with the goal to increase tolerance, initially through desensitization, which relies on regular exposure to allergen. With prolonged therapy in some subjects, AIT may induce sustained unresponsiveness, in which tolerance is retained after a period of allergen avoidance. Methods of AIT currently under study in humans include oral, sublingual, epicutaneous, and subcutaneous delivery of modified allergenic protein, as well as via DNA-based vaccines encoding allergen with lysosomal-associated membrane protein I. The balance of safety and efficacy varies by type of AIT, as well as by targeted allergen. Age, degree of sensitization, and other comorbidities may affect this balance within an individual patient. More recently, AIT with modified proteins or combined with immunomodulatory therapies has shown promise in making AIT safer and/or more effective. Though methods of AIT are neither currently advised by experts (oral immunotherapy [OIT]) nor widely available, AIT is likely to become a part of recommended management of FA in the coming years. Here, we review and compare methods of AIT currently under study in humans to prepare the practitioner for an exciting new phase in the care of food allergic patients in which improved tolerance to inciting foods will be a real possibility. PMID:29676066

  9. Comparison of immunoglobulin E measurements on IMMULITE and ImmunoCAP in samples consisting of allergen-specific mouse-human chimeric monoclonal antibodies towards allergen extracts and four recombinant allergens.

    PubMed

    Szecsi, Pal B; Stender, Steen

    2013-01-01

    Specific immunoglobulin E (IgE) antibody in vitro tests are performed on enzyme immunoassay systems. Poor agreement among systems has been reported and comparisons have been made exclusively with allergen extracts - not with recombinant allergens. Here we compare the ImmunoCAP and the IMMULITE systems. Ten patient samples with positive IgE toward egg white, birch pollen or cat or dog dander were compared using allergen extracts or the recombinant allergens Gal d 1, Bet v 1, Fel d 1 and Can f 1 with the two assay systems. Comparisons were also performed using four monoclonal mouse-human chimeric IgE antibodies specific for the same allergenic components. IMMULITE estimated a higher allergen-specific IgE concentration in sera than ImmunoCAP when testing with allergen extracts as well as recombinant allergens. The chimeric antibodies gave an equivalent response in the total IgE and specific IgE (sIgE) with an average ratio of 1.08 (range 0.9-1.3) on ImmunoCAP. In contrast, IMMULITE exhibited sIgE signals that were substantially higher than the summed level of IgE for all four chimeric antibodies (average ratio 2.96 and range 1.7-4.3). Comparison using chimeric antibodies allowed the evaluation of the true performance of the systems. ImmunoCAP measured total IgE and sIgE equally, whereas IMMULITE displayed higher sIgE signals when compared to the summed level of total IgE for all four chimeric antibodies. Results obtained with the two assay systems are not interchangeable by means of mathematical conversion. Copyright © 2013 S. Karger AG, Basel.

  10. Effect of thalidomide on endotoxin-induced decreases in activity and expression of hepatic cytochrome P450 3A2.

    PubMed

    Ueyama, Jun; Nadai, Masayuki; Zhao, Ying Lan; Kanazawa, Hiroaki; Takagi, Kenji; Kondo, Takaaki; Takagi, Kenzo; Wakusawa, Shinya; Abe, Fumie; Saito, Hiroko; Miyamoto, Ken-Ichi; Hasegawa, Takaaki

    2008-08-01

    Thalidomide has been reported to inhibit the production of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) that are involved in the down-regulation of hepatic cytochrome P450 (CYP) induced by endotoxin. In the present study, we investigated the effects of thalidomide on endotoxin-induced decreases in the activity and expression of hepatic CYP3A2 in rats. Thalidomide (50 mg/kg) was administered orally 22 h and 2 h before intraperitoneal injection of endotoxin (1 mg/kg). Twenty-four hours after the injection of endotoxin, antipyrine clearance experiments were conducted, in which the rats were sacrificed and protein levels of hepatic CYP3A2 were measured. There were no significant differences in the histopathological changes in the liver between the endotoxin-treated and endotoxin plus thalidomide-treated rats. Thalidomide had no effect on the systemic clearance of antipyrine, which is a proper indicator for hepatic CYP3A2 activity, whereas it enhanced endotoxin-induced decrease in the systemic clearance of antipyrine. Western blot analysis revealed that thalidomide had no effect on the protein levels of hepatic CYP3A2, whereas it enhanced the down-regulation of hepatic CYP3A2 by endotoxin. However, there were no significant differences in the concentrations of TNF-alpha and NO in plasma between the endotoxin-treated and endotoxin plus thalidomide-treated rats. The present findings suggest that thalidomide enhances endotoxin-induced decreases in the activity and expression of hepatic CYP3A2.

  11. State Indoor Tanning Laws and Adolescent Indoor Tanning

    PubMed Central

    Guy, Gery P.; Berkowitz, Zahava; Jones, Sherry Everett; O’Malley Olsen, Emily; Miyamoto, Justin N.; Michael, Shannon L.; Saraiya, Mona

    2014-01-01

    Objectives. Recently, several state indoor tanning laws, including age restrictions, were promulgated to reduce indoor tanning among minors. We examined the effects of these laws on adolescent indoor tanning. Methods. We used nationally representative data from the 2009 and 2011 national Youth Risk Behavior Surveys (n = 31 835). Using multivariable logistic regression, we examined the association between state indoor tanning laws and indoor tanning among US high school students. Results. Female students in states with indoor tanning laws were less likely to engage in indoor tanning than those in states without any laws. We observed a stronger association among female students in states with systems access, parental permission, and age restriction laws than among those in states without any laws. We found no significant association among female students in states with only systems access and parental permission laws or among male students. Conclusions. Indoor tanning laws, particularly those including age restrictions, may be effective in reducing indoor tanning among female high school students, for whom rates are the highest. Such reductions have the potential to reduce the health and economic burden of skin cancer. PMID:24524515

  12. In vivo effects of endotoxin on DNA synthesis in rat nasal epithelium

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

    Harkema, J.R.; Hotchkiss, J.A.

    Airway inflammation in bacterial infections is characterized by the presence of neutrophils and often epithelial injury and repair. Release of endotoxin from bacteria may contribute to these processes. The purpose of this study was to determine the in vivo effects of repeated endotoxin exposure on DNA synthesis in rat nasal epithelium in the presence and absence of neutrophilic influx. Rats were intranasally instilled, once a day for 3 days, with endotoxin or saline (controls). Before the first and third instillations, half of the saline and endotoxin-instilled animals were depleted of circulating blood neutrophils by administering a rabbit anti-rat neutrophil antiserum.more » Rats were sacrificed 6 or 24 h after the last instillation. Two hours prior to sacrifice, rats were intraperitoneally injected with bromodeoxyuridine (BrdU), an analog of thymidine that is incorporated in the nucleus of cells in the S-phase of the cell cycle. Nasal tissues were processed for light microscopy and immunohistochemical detection of BrdU in nasal epithelial cells. The numbers of nasal epithelial cells, BrdU-labeled epithelial nuclei, and neutrophils per millimeter of basal lamina in the epithelium lining the nasal turbinates in the proximal nasal passages were determined by morphometric analysis. The authors did not observe a neutrophilic influx in the nasal tissues of neutrophil-depleted rats at 6 or 24 h after the last endotoxin instillation; however, the numbers of nasal epithelial cells and the BrdU-labeling index were significantly increased compared to saline-instilled controls. In contrast, non-neutrophil-depleted rats instilled with endotoxin had a marked neutrophilic influx, but no significant differences in the number of nasal epithelial cells at 6 or 24 h, compared to controls. In addition, the BrdU-labeling index in neutrophil-sufficient rats was increased only 6 h after the last instillation, compared to controls.« less

  13. Sensitive detection of major food allergens in breast milk: first gateway for allergenic contact during breastfeeding.

    PubMed

    Pastor-Vargas, C; Maroto, A S; Díaz-Perales, A; Villaba, M; Casillas Diaz, N; Vivanco, F; Cuesta-Herranz, J

    2015-08-01

    Food allergy is recognized as a major public health issue, especially in early childhood. It has been hypothesized that early sensitization to food allergens maybe due to their ingestion as components dissolved in the milk during the breastfeeding, explaining reaction to a food, which has never been taken before. Thus, the aim of this work has been to detect the presence of the food allergens in breast milk by microarray technology. We produced a homemade microarray with antibodies produced against major food allergens. The antibody microarray was incubated with breast milk from 14 women collected from Fundación Jiménez Díaz Hospital. In this way, we demonstrated the presence of major foods allergens in breast milk. The analysis of allergens presented in breast milk could be a useful tool in allergy prevention and could provide us a key data on the role of this feeding in tolerance induction or sensitization in children. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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

    PubMed

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

    2010-10-01

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

  15. Endotoxin, Toll-like Receptor-4, and Atherosclerotic Heart Disease

    PubMed Central

    Horseman, Michael A.; Surani, Salim; Bowman, John D.

    2017-01-01

    Background: Endotoxin is a lipopolysaccharide (LPS) constituent of the outer membrane of most gram negative bacteria. Ubiquitous in the environment, it has been implicated as a cause or con-tributing factor in several disparate disorders from sepsis to heatstroke and Type II diabetes mellitus. Starting at birth, the innate immune system develops cellular defense mechanisms against environmen-tal microbes that are in part modulated through a series of receptors known as toll-like receptors. Endo-toxin, often referred to as LPS, binds to toll-like receptor 4 (TLR4)/ myeloid differentiation protein 2 (MD2) complexes on various tissues including cells of the innate immune system, smooth muscle and endothelial cells of blood vessels including coronary arteries, and adipose tissue. Entry of LPS into the systemic circulation ultimately leads to intracellular transcription of several inflammatory mediators. The subsequent inflammation has been implicated in the development and progression atherosclerosis and subsequent coronary artery disease and heart failure. Objective: The potential roles of endotoxin and TLR4 are reviewed regarding their role in the pathogen-esis of atherosclerotic heart disease. Conclusion: Atherosclerosis is initiated by inflammation in arterial endothelial and subendothelial cells, and inflammatory processes are implicated in its progression to clinical heart disease. Endotoxin and TLR4 play a central role in the inflammatory process, and represent potential targets for therapeutic intervention. Therapy with HMG-CoA inhibitors may reduce the expression of TLR4 on monocytes. Other therapeutic interventions targeting TLR4 expression or function may prove beneficial in athero-sclerotic disease prevention and treatment.

  16. Distribution of peanut allergen in the environment.

    PubMed

    Perry, Tamara T; Conover-Walker, Mary Kay; Pomés, Anna; Chapman, Martin D; Wood, Robert A

    2004-05-01

    Patients with peanut allergy can have serious reactions to very small quantities of peanut allergen and often go to extreme measures to avoid potential contact with this allergen. The purpose of this study was to detect peanut allergen under various environmental conditions and examine the effectiveness of cleaning agents for allergen removal. A monoclonal-based ELISA for Arachis hypogaea allergen 1 (Ara h 1; range of detection, 30-2000 ng/mL) was used to assess peanut contamination on cafeteria tables and other surfaces in schools, the presence of residual peanut protein after using various cleaning products on hands and tabletops, and airborne peanut allergen during the consumption of several forms of peanut. After hand washing with liquid soap, bar soap, or commercial wipes, Ara h 1 was undetectable. Plain water and antibacterial hand sanitizer left detectable Ara h 1 on 3 of 12 and 6 of 12 hands, respectively. Common household cleaning agents removed peanut allergen from tabletops, except dishwashing liquid, which left Ara h 1 on 4 of 12 tables. Of the 6 area preschools and schools evaluated, Ara h 1 was found on 1 of 13 water fountains, 0 of 22 desks, and 0 of 36 cafeteria tables. Airborne Ara h 1 was undetectable in simulated real-life situations when participants consumed peanut butter, shelled peanuts, and unshelled peanuts. The major peanut allergen, Ara h 1, is relatively easily cleaned from hands and tabletops with common cleaning agents and does not appear to be widely distributed in preschools and schools. We were not able to detect airborne allergen in many simulated environments.

  17. Allergenic potential of novel foods.

    PubMed

    Meredith, Clive

    2005-11-01

    Concerns have been expressed that the introduction of novel foods into the diet might lead to the development of new food allergies in consumers. Novel foods can be conveniently divided into GM and non-GM categories. Decision-tree approaches (e.g. International Life Sciences Institute-International Food Biotechnology Council and WHO/FAO) to assess the allergenic potential of GM foods were developed following the discovery, during product development, of the allergenic potential of GM soyabean expressing a gene encoding a storage protein from Brazil nut (Bertolletia excelsa). Within these decision trees considerations include: the source of the transgene; amino acid homology with known allergens; cross-reactivity with IgE from food-allergic individuals; resistance to proteolysis; prediction using animal models of food allergy. Such decision trees are under constant review as new knowledge and improved models emerge, but they provide a useful framework for the assessment of the allergenic potential of GM foods. For novel non-GM foods the assessment of allergenic potential is more subjective; some foods or food ingredients will need no assessment other than a robust protein assay to demonstrate the absence of protein. Where protein is present in the novel non-GM food, hazard and risk assessments need to be made in terms of the quantity of protein that might be consumed, the identity of individual protein components and their relationships to known food allergens. Where necessary, this assessment would extend to serum screening for potential cross-reactivities, skin-prick tests in previously-sensitised individuals and double-blind placebo-controlled food challenges.

  18. Environmental Issues in Managing Asthma

    PubMed Central

    Diette, Gregory B; McCormack, Meredith C; Hansel, Nadia N; Breysse, Patrick N; Matsui, Elizabeth C

    2008-01-01

    Management of asthma requires attention to environmental exposures both indoors and outdoors. Americans spend most of their time indoors, where they have a greater ability to modify their environment. The indoor environment contains both pollutants (eg, particulate matter, nitrogen dioxide, secondhand smoke, and ozone) and allergens from furred pets, dust mites, cockroaches, rodents, and molds. Indoor particulate matter consists of particles generated from indoor sources such as cooking and cleaning activities, and particles that penetrate from the outdoors. Nitrogen dioxide sources include gas stoves, furnaces, and fireplaces. Indoor particulate matter and nitrogen dioxide are linked to asthma morbidity. The indoor ozone concentration is mainly influenced by the outdoor ozone concentration. The health effects of indoor ozone exposure have not been well studied. In contrast, there is substantial evidence of detrimental health effects from secondhand smoke. Guideline recommendations are not specific for optimizing indoor air quality. The 2007 National Asthma Education and Prevention Program asthma guidelines recommend eliminating indoor smoking and improving the ventilation. Though the guidelines state that there is insufficient evidence to recommend air cleaners, air cleaners and reducing activities that generate indoor pollutants may be sound practical approaches for improving the health of individuals with asthma. The guidelines are more specific about allergen avoidance; they recommend identifying allergens to which the individual is immunoglobin E sensitized and employing a multifaceted, comprehensive strategy to reduce exposure. Outdoor air pollutants that impact asthma include particulate matter, ozone, nitrogen dioxide, and sulfur dioxide, and guidelines recommend that individuals with asthma avoid exertion outdoors when these pollutants are elevated. Outdoor allergens include tree, grass, and weed pollens, which vary in concentration by season

  19. Criteria to determine food allergen priority.

    PubMed

    Yeung, J M; Applebaum, R S; Hildwine, R

    2000-07-01

    The emergent health issue of food allergens presents an important challenge to the food industry. More than 170 foods have been reported in the scientific literature as causing allergic reactions. Clearly, it would be impossible to deal with the presence of trace amounts of all these in the context of food labeling. If the decision to classify major allergens is based solely on the knowledge and experience of allergists and food scientists in the field, without scientifically defined criteria, it is likely to lead to a proliferation of lists. Such practices may lead to an unnecessary elimination of foods containing important nutrients. This paper defines food allergy, food intolerance, and food anaphylaxis and identifies criteria for classifying food allergens associated with frequent allergic reactions. A practical list of food allergens that may result in potentially life-threatening allergic reactions is provided. A mechanism-based (i.e., immunoglobulin E mediated), acute life-threatening anaphylaxis that is standardized and measurable and reflects the severity of health risk is proposed as the principal inclusion criterion for food allergen labeling. Where available, prevalence in the population and threshold levels of allergens should be used as an additional guide to identify possible future labeling needs.

  20. Influence of apical enlargement and complementary canal preparation with the Self-Adjusting File on endotoxin reduction in retreatment cases.

    PubMed

    Silva, E J N L; Ferreira, V M; Silva, C C; Herrera, D R; De-Deus, G; Gomes, B P

    2017-07-01

    To compare the effectiveness of large apical preparations and complementary canal preparation with the Self-Adjusting File (SAF) in removing endotoxins from the root canal of teeth with apical periodontitis. Ten single-rooted and single-canaled teeth with post-treatment apical periodontitis were selected. Endotoxin samples were taken after removal of the root filling (S1), after chemomechanical preparation (CMP) using 2.5% NaOCl and an R25 file (S2), after CMP using 2.5% NaOCl and an R40 file (S3) and after complementary CMP using the SAF system (S4). Limulus amebocyte lysate (LAL) was used to measure endotoxin levels. The Friedman and Wilcoxon tests were used to compare endotoxin levels at each clinical intervention (P < 0.05). After root filling removal, endotoxin was detected in 100% of the root canals (S1, 4.84 EU mL -1 ). CMP with the R25 file was able to significantly reduce endotoxin levels (P < 0.05). Increased levels of endotoxin removal were achieved by apical preparation with the R40 file (P < 0.05). Complementary CMP with SAF did not significantly reduce endotoxin levels (P > 0.05) following the use of the R40 instrument. Apical enlargement protocols were effective in significantly reducing endotoxin levels. Complementary preparation with the SAF system failed to eliminate residual endotoxin contents beyond those obtained with the R40 instrument. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  1. Indoor Subspacing to Implement Indoorgml for Indoor Navigation

    NASA Astrophysics Data System (ADS)

    Jung, H.; Lee, J.

    2015-10-01

    According to an increasing demand for indoor navigation, there are great attempts to develop applicable indoor network. Representation for a room as a node is not sufficient to apply complex and large buildings. As OGC established IndoorGML, subspacing to partition the space for constructing logical network is introduced. Concerning subspacing for indoor network, transition space like halls or corridors also have to be considered. This study presents the subspacing process for creating an indoor network in shopping mall. Furthermore, categorization of transition space is performed and subspacing of this space is considered. Hall and squares in mall is especially defined for subspacing. Finally, implementation of subspacing process for indoor network is presented.

  2. Comparison of Air Impaction and Electrostatic Dust Collector Sampling Methods to Assess Airborne Fungal Contamination in Public Buildings.

    PubMed

    Normand, Anne-Cécile; Ranque, Stéphane; Cassagne, Carole; Gaudart, Jean; Sallah, Kankoé; Charpin, Denis-André; Piarroux, Renaud

    2016-03-01

    Many ailments can be linked to exposure to indoor airborne fungus. However, obtaining a precise measurement of airborne fungal levels is complicated partly due to indoor air fluctuations and non-standardized techniques. Electrostatic dust collector (EDC) sampling devices have been used to measure a wide range of airborne analytes, including endotoxins, allergens, β-glucans, and microbial DNA in various indoor environments. In contrast, viable mold contamination has only been assessed in highly contaminated environments such as farms and archive buildings. This study aimed to assess the use of EDCs, compared with repeated air-impactor measurements, to assess airborne viable fungal flora in moderately contaminated indoor environments. Indoor airborne fungal flora was cultured from EDCs and daily air-impaction samples collected in an office building and a daycare center. The quantitative fungal measurements obtained using a single EDC significantly correlated with the cumulative measurement of nine daily air impactions. Both methods enabled the assessment of fungal exposure, although a few differences were observed between the detected fungal species and the relative quantity of each species. EDCs were also used over a 32-month period to monitor indoor airborne fungal flora in a hospital office building, which enabled us to assess the impact of outdoor events (e.g. ground excavations) on the fungal flora levels on the indoor environment. In conclusion, EDC-based measurements provided a relatively accurate profile of the viable airborne flora present during a sampling period. In particular, EDCs provided a more representative assessment of fungal levels compared with single air-impactor sampling. The EDC technique is also simpler than performing repetitive air-impaction measures over the course of several consecutive days. EDC is a versatile tool for collecting airborne samples and was efficient for measuring mold levels in indoor environments. © The Author 2015

  3. Removal of endotoxin from dairy wastewater

    USDA-ARS?s Scientific Manuscript database

    The efficacy of various treatments on removing endotoxin (ET) from wastewater was tested by using the treated water to induce a systemic reaction via intratracheal inoculation (20 ml/goat, 6 goats/group). Treatments (T1-T7) of wastewater were as follows: 1) autoclaved 15 min, centrifuged and contain...

  4. Low-cost interventions improve indoor air quality and children's health.

    PubMed

    Johnson, Linda; Ciaccio, Christina; Barnes, Charles S; Kennedy, Kevin; Forrest, Erika; Gard, Luke C; Pacheco, Freddy; Dowling, Paul; Portnoy, Jay M

    2009-01-01

    Intervention in the home environment to reduce asthma triggers theoretically improves health outcomes for asthmatic children. Practical benefit from application of these interventions has proven difficult. This single-blind study tested the effectiveness of simple low-cost home interventions in improving health scores of children with asthma. Families with at least one asthmatic child were recruited. Initial health examination, health, and home assessments were conducted and targeted interventions were implemented. Interventions included dehumidification, air filtration, furnace servicing, and high-efficiency furnace filters. When present, gross fungal contamination was remediated. Asthma education was provided along with education in healthy home practices. Follow-up assessments were conducted after 6 months. Health surveys were completed at enrollment and follow-up. This study enrolled 219 children with asthma. Home inspections and interventions were conducted in 181 homes and 83 families completed all phases. Reduction in asthma and allergy-related health scores was shown in follow-up health surveys. Health improvements were significant for cough when heating, ventilation, and air conditioning (HVAC) service and dehumidification were used. Breathing problems were significantly improved for dehumidification, HVAC service, and room air cleaners. Total dust allergen load was reduced for the dehumidification group (p < 0.05). Mold spore counts were reduced one order of magnitude in 25% of the homes. Indoor spore counts adjusted for outdoor spore levels were reduced overall (p < 0.01). Simple low-cost interventions directed to producing cleaner indoor air coupled with healthy home education improve the indoor air quality and health in asthmatic children.

  5. [Changes of cementum endotoxin levels in different teeth with periodontitis treated with root conditioning].

    PubMed

    Fu, Chang-Sheng; Liu, Rong-Sen; Luo, Yun; Ou, Long; Li, Ying-Chao; Zhang, Xian-Hua

    2017-04-01

    To observe the changes of endotoxin levels after different teeth with periodontitis were treated with different methods. METHODS: Six healthy premolars extracted for orthodontic reasons and 36 posterior teeth extracted due to severe periodontitis were selected. Each tooth was processed from two 4 mm×4 mm×1 mm cementum pieces 2 mm under the cementum-enamel junction, each tooth with periodontitis was numbered. Healthy teeth served as negative control group, one of the two tablets from each tooth with periodontitis was selected in the periodontitis group, which was not treated with root surface treatment. The remaining 36 teeth with periodontitis were randomly divided into 6 groups: SRP group, SRP + antimicrobial peptide A group , SRP + antimicrobial peptide B group, SRP + EDTA group, SRP + Er:YAG laser group and SRP + Nd:YAG laser group. Endotoxin concentration in each tooth was determined by chromogenic substrate limulus reagent. The endotoxin concentration in each tooth was recorded according to the serial number, and the changes of endotoxin concentration were calculated before and after treatment. SPSS17.0 software package was used to analyze the data. Compared with the teeth with periodontitis, endotoxin concentration decreased to varying degrees, there were significant differences in each treatment group(P<0.01). Compared with SRP group, endotoxin levels in SRP + antimicrobial peptide A group, SRP + antimicrobial peptide B group, SRP + Er:YAG laser group were significantly decreased(P<0.01). No significant difference decreased was from between SRP + EDTA group and SRP + Nd:YAG laser group(P>0.05). Treatment of teeth with periodontitis using different methods can decrease the level of endotoxin, and the treatment of periodontitis root surface with antimicrobial peptide A + SRP may be more effective.

  6. Current Status of Standardization of Inhalant Allergen Extracts in Korea

    PubMed Central

    Jeong, Kyoung Yong; Lee, Jae-Hyun; Kim, Eun-Jin; Lee, Joo-Shil; Cho, Sang-Heon; Hong, Soo-Jong

    2014-01-01

    Allergy diagnosis and immunotherapy in Korea rely mostly on imported allergen extracts. However, some allergens that are not important in Western countries are not commercially available, and even the same species of allergen source often displays differences in allergenicity due to amino acid sequence polymorphisms. Therefore, it is essential to prepare allergen extracts that reflect regional characteristics. Allergen standardization has been performed since 2009 with the support of the Korea Center for Disease Control and Prevention. Here, we summarize the current status of allergen standardization, focusing on the house dust mite and cockroach. Pollen allergens that are under investigation are also briefly described. PMID:24843793

  7. The effects of indoor environmental exposures on pediatric asthma: a discrete event simulation model.

    PubMed

    Fabian, M Patricia; Stout, Natasha K; Adamkiewicz, Gary; Geggel, Amelia; Ren, Cizao; Sandel, Megan; Levy, Jonathan I

    2012-09-18

    In the United States, asthma is the most common chronic disease of childhood across all socioeconomic classes and is the most frequent cause of hospitalization among children. Asthma exacerbations have been associated with exposure to residential indoor environmental stressors such as allergens and air pollutants as well as numerous additional factors. Simulation modeling is a valuable tool that can be used to evaluate interventions for complex multifactorial diseases such as asthma but in spite of its flexibility and applicability, modeling applications in either environmental exposures or asthma have been limited to date. We designed a discrete event simulation model to study the effect of environmental factors on asthma exacerbations in school-age children living in low-income multi-family housing. Model outcomes include asthma symptoms, medication use, hospitalizations, and emergency room visits. Environmental factors were linked to percent predicted forced expiratory volume in 1 second (FEV1%), which in turn was linked to risk equations for each outcome. Exposures affecting FEV1% included indoor and outdoor sources of NO2 and PM2.5, cockroach allergen, and dampness as a proxy for mold. Model design parameters and equations are described in detail. We evaluated the model by simulating 50,000 children over 10 years and showed that pollutant concentrations and health outcome rates are comparable to values reported in the literature. In an application example, we simulated what would happen if the kitchen and bathroom exhaust fans were improved for the entire cohort, and showed reductions in pollutant concentrations and healthcare utilization rates. We describe the design and evaluation of a discrete event simulation model of pediatric asthma for children living in low-income multi-family housing. Our model simulates the effect of environmental factors (combustion pollutants and allergens), medication compliance, seasonality, and medical history on asthma outcomes

  8. The effects of indoor environmental exposures on pediatric asthma: a discrete event simulation model

    PubMed Central

    2012-01-01

    Background In the United States, asthma is the most common chronic disease of childhood across all socioeconomic classes and is the most frequent cause of hospitalization among children. Asthma exacerbations have been associated with exposure to residential indoor environmental stressors such as allergens and air pollutants as well as numerous additional factors. Simulation modeling is a valuable tool that can be used to evaluate interventions for complex multifactorial diseases such as asthma but in spite of its flexibility and applicability, modeling applications in either environmental exposures or asthma have been limited to date. Methods We designed a discrete event simulation model to study the effect of environmental factors on asthma exacerbations in school-age children living in low-income multi-family housing. Model outcomes include asthma symptoms, medication use, hospitalizations, and emergency room visits. Environmental factors were linked to percent predicted forced expiratory volume in 1 second (FEV1%), which in turn was linked to risk equations for each outcome. Exposures affecting FEV1% included indoor and outdoor sources of NO2 and PM2.5, cockroach allergen, and dampness as a proxy for mold. Results Model design parameters and equations are described in detail. We evaluated the model by simulating 50,000 children over 10 years and showed that pollutant concentrations and health outcome rates are comparable to values reported in the literature. In an application example, we simulated what would happen if the kitchen and bathroom exhaust fans were improved for the entire cohort, and showed reductions in pollutant concentrations and healthcare utilization rates. Conclusions We describe the design and evaluation of a discrete event simulation model of pediatric asthma for children living in low-income multi-family housing. Our model simulates the effect of environmental factors (combustion pollutants and allergens), medication compliance, seasonality

  9. Comparison of international food allergen labeling regulations.

    PubMed

    Gendel, Steven M

    2012-07-01

    Food allergy is a significant public health issue worldwide. Regulatory risk management strategies for allergic consumers have focused on providing information about the presence of food allergens through label declarations. A number of countries and regulatory bodies have recognized the importance of providing this information by enacting laws, regulations or standards for food allergen labeling of "priority allergens". However, different governments and organizations have taken different approaches to identifying these "priority allergens" and to designing labeling declaration regulatory frameworks. The increasing volume of the international food trade suggests that there would be value in supporting sensitive consumers by harmonizing (to the extent possible) these regulatory frameworks. As a first step toward this goal, an inventory of allergen labeling regulations was assembled and analyzed to identify commonalities, differences, and future needs. Published by Elsevier Inc.

  10. Assessing endotoxins in equine-derived snake antivenoms: Comparison of the USP pyrogen test and the Limulus Amoebocyte Lysate assay (LAL).

    PubMed

    Solano, Gabriela; Gómez, Aarón; León, Guillermo

    2015-10-01

    Snake antivenoms are parenterally administered; therefore, endotoxin content must be strictly controlled. Following international indications to calculate endotoxin limits, it was determined that antivenom doses between 20 mL and 120 mL should not exceed 17.5 Endotoxin Units per milliliter (EU/mL) and 2.9 EU/mL, respectively. The rabbit pyrogen test (RPT) has been used to evaluate endotoxin contamination in antivenoms, but some laboratories have recently implemented the LAL assay. We compared the capability of both tests to evaluate endotoxin contamination in antivenoms, and we found that both methods can detect all endotoxin concentrations in the range of the antivenom specifications. The acceptance criteria of RPT and LAL must be harmonized by calculating the endotoxin limit as the quotient of the threshold pyrogenic dose and the therapeutic dose and the dose administered to rabbits as the quotient of the threshold pyrogenic dose and the endotoxin limit. Since endotoxins from Gram-negative bacteria exert different pyrogenicity, if contamination occurred, antivenom batches that induce pyrogenic reactions may be found in spite of passing LAL specifications. Although LAL assay can be used to assess endotoxin content throughout the antivenom manufacturing process, we recommend that the release of final products be based on the results of both methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    PubMed Central

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

    2012-01-01

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

  12. Soft-X-ray-enhanced electrostatic precipitation for protection against inhalable allergens, ultrafine particles, and microbial infections.

    PubMed

    Kettleson, Eric M; Schriewer, Jill M; Buller, R Mark L; Biswas, Pratim

    2013-02-01

    Protection of the human lung from infectious agents, allergens, and ultrafine particles is difficult with current technologies. High-efficiency particulate air (HEPA) filters remove airborne particles of >0.3 μm with 99.97% efficiency, but they are expensive to maintain. Electrostatic precipitation has been used as an inexpensive approach to remove large particles from airflows, but it has a collection efficiency minimum in the submicrometer size range, allowing for a penetration window for some allergens and ultrafine particles. Incorporating soft X-ray irradiation as an in situ component of the electrostatic precipitation process greatly improves capture efficiency of ultrafine particles. Here we demonstrate the removal and inactivation capabilities of soft-X-ray-enhanced electrostatic precipitation technology targeting infectious agents (Bacillus anthracis, Mycobacterium bovis BCG, and poxviruses), allergens, and ultrafine particles. Incorporation of in situ soft X-ray irradiation at low-intensity corona conditions resulted in (i) 2-fold to 9-fold increase in capture efficiency of 200- to 600-nm particles and (ii) a considerable delay in the mean day of death as well as lower overall mortality rates in ectromelia virus (ECTV) cohorts. At the high-intensity corona conditions, nearly complete protection from viral and bacterial respiratory infection was afforded to the murine models for all biological agents tested. When optimized for combined efficient particle removal with limited ozone production, this technology could be incorporated into stand-alone indoor air cleaners or scaled for installation in aircraft cabin, office, and residential heating, ventilating, and air-conditioning (HVAC) systems.

  13. Soft-X-Ray-Enhanced Electrostatic Precipitation for Protection against Inhalable Allergens, Ultrafine Particles, and Microbial Infections

    PubMed Central

    Kettleson, Eric M.; Schriewer, Jill M.; Buller, R. Mark L.

    2013-01-01

    Protection of the human lung from infectious agents, allergens, and ultrafine particles is difficult with current technologies. High-efficiency particulate air (HEPA) filters remove airborne particles of >0.3 μm with 99.97% efficiency, but they are expensive to maintain. Electrostatic precipitation has been used as an inexpensive approach to remove large particles from airflows, but it has a collection efficiency minimum in the submicrometer size range, allowing for a penetration window for some allergens and ultrafine particles. Incorporating soft X-ray irradiation as an in situ component of the electrostatic precipitation process greatly improves capture efficiency of ultrafine particles. Here we demonstrate the removal and inactivation capabilities of soft-X-ray-enhanced electrostatic precipitation technology targeting infectious agents (Bacillus anthracis, Mycobacterium bovis BCG, and poxviruses), allergens, and ultrafine particles. Incorporation of in situ soft X-ray irradiation at low-intensity corona conditions resulted in (i) 2-fold to 9-fold increase in capture efficiency of 200- to 600-nm particles and (ii) a considerable delay in the mean day of death as well as lower overall mortality rates in ectromelia virus (ECTV) cohorts. At the high-intensity corona conditions, nearly complete protection from viral and bacterial respiratory infection was afforded to the murine models for all biological agents tested. When optimized for combined efficient particle removal with limited ozone production, this technology could be incorporated into stand-alone indoor air cleaners or scaled for installation in aircraft cabin, office, and residential heating, ventilating, and air-conditioning (HVAC) systems. PMID:23263945

  14. Identification of autoclave-resistant Anisakis simplex allergens.

    PubMed

    Carballeda-Sangiao, Noelia; Olivares, Fabiola; Rodriguez-Mahillo, Ana I; Careche, Mercedes; Tejada, Margarita; Moneo, Ignacio; González-Muñoz, Miguel

    2014-04-01

    Anisakis simplex is a fish parasite able to induce allergic reactions in humans infected when eating raw or undercooked fish parasitized with viable third-stage larvae. Some authors claim that exposure to nonviable Anisakis material can result in allergic symptoms in previously sensitized patients, indicating that parasite allergens are resistant to the thermal treatments of usual cooking procedures. Furthermore, some patients report symptoms after eating canned fish. The aim of this work was the analysis of parasite allergen stability in heating to 121 °C in an autoclave to simulate the thermal process applied to canned fish. Third-stage larvae were subjected to autoclaving for 20, 40, and 80 min, and parasite crude extracts were analyzed by electrophoresis, immunoblotting, and a flow-cytometric basophil activation test. Allergens resistant to autoclaving were separated by reversed-phase high-performance liquid chromatography and identified by ion trap mass spectrometry. Protein analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that autoclaving considerably reduced the number and intensity of identifiable protein bands in a time-dependent manner. Several allergens were detected by immunoblotting with a pool of A. simplex allergic patients' sera after autoclaving. Allergens of 9 and 14 kDa resistant to autoclaving were identified as Ani s 4 and Ani s 1 allergens, respectively. Functional analysis showed that allergens retain their capacity to activate basophils even after autoclaving for 80 min. In conclusion, some relevant A. simplex allergens retain their capacity to bind immunoglobulin E and activate basophils after being subjected to autoclaving, which is a method equivalent to that used in industrial canning processes.

  15. Contribution of solid fuel, gas combustion, or tobacco smoke to indoor air pollutant concentrations in Irish and Scottish homes.

    PubMed

    Semple, S; Garden, C; Coggins, M; Galea, K S; Whelan, P; Cowie, H; Sánchez-Jiménez, A; Thorne, P S; Hurley, J F; Ayres, J G

    2012-06-01

      There are limited data describing pollutant levels inside homes that burn solid fuel within developed country settings with most studies describing test conditions or the effect of interventions. This study recruited homes in Ireland and Scotland where open combustion processes take place. Open combustion was classified as coal, peat, or wood fuel burning, use of a gas cooker or stove, or where there is at least one resident smoker. Twenty-four-hour data on airborne concentrations of particulate matter<2.5 μm in size (PM2.5), carbon monoxide (CO), endotoxin in inhalable dust and carbon dioxide (CO2), together with 2-3 week averaged concentrations of nitrogen dioxide (NO2) were collected in 100 houses during the winter and spring of 2009-2010. The geometric mean of the 24-h time-weighted-average (TWA) PM2.5 concentration was highest in homes with resident smokers (99 μg/m3--much higher than the WHO 24-h guidance value of 25 μg/m3). Lower geometric mean 24-h TWA levels were found in homes that burned coal (7 μg/m3) or wood (6 μg/m3) and in homes with gas cookers (7 μg/m3). In peat-burning homes, the average 24-h PM2.5 level recorded was 11 μg/m3. Airborne endotoxin, CO, CO2, and NO2 concentrations were generally within indoor air quality guidance levels. Little is known about indoor air quality (IAQ) in homes that burn solid or fossil-derived fuels in economically developed countries. Recent legislative changes have moved to improve IAQ at work and in enclosed public places, but there remains a real need to begin the process of quantifying the health burden that arises from indoor air pollution within domestic environments. This study demonstrates that homes in Scotland and Ireland that burn solid fuels or gas for heating and cooking have concentrations of air pollutants generally within guideline levels. Homes where combustion of cigarettes takes place have much poorer air quality. © 2011 John Wiley & Sons A/S.

  16. Allergens labeling on French processed foods - an Oqali study.

    PubMed

    Battisti, Charlène; Chambefort, Amélie; Digaud, Olivier; Duplessis, Barbara; Perrin, Cécile; Volatier, Jean-Luc; Gauvreau-Béziat, Julie; Menard, Céline

    2017-07-01

    The French Observatory of Food Quality (Oqali) aims at collecting all nutritional data provided on labels of processed foods (nutritional information and composition), at branded products level, in order to follow nutritional labeling changes over time. This study carries out an overview of allergens labeling frequencies by distinguishing allergens used in recipes from those listed on precautionary statements, for the fourteen allergen categories for which labeling is mandatory according to European legislation. 17,309 products were collected, between 2008 and 2012, from 26 food categories. Products were classified per family and type of brand (national brands, retailer brands, entry-level retailer brands, hard discount, and specialized retailer brands). Allergenic ingredients were identified from ingredients lists and precautionary statements. 73% of the 17,309 products studied contained at least one allergen in their ingredients list and 39% had a precautionary statement for one or more allergens. Milk (53%), gluten (41%), and egg (22%) were the most commonly used allergens in ingredients lists. For precautionary statement, nuts (20%), egg (14%), peanut (13%), soybean (12%), and milk (11%) were the most common allergens listed. Precautionary statement was most frequently found among first-price products (hard discount and entry-level retailer brands). National brands seemed to use it less frequently. For all these results, differences depended both on food categories and allergen categories. This study will enable to follow allergens labeling and their use as ingredients over time, particularly by assessing an hypothetical increase in allergens presence in processed food.

  17. Inhaled endotoxin and organic dust particulates have synergistic proinflammatory effects in equine heaves (organic dust-induced asthma).

    PubMed

    Pirie, R S; Collie, D D S; Dixon, P M; McGorum, B C

    2003-05-01

    Equine heaves is a naturally occurring organic dust-induced asthma characterized by airway neutrophilia, mucus hypersecretion and obstructive lung dysfunction. However, the relative role of different dust components in disease severity remains unclear. This study investigated the relative contribution of inhaled endotoxin and organic dust particulates (mainly mould spores) in inducing heaves in heaves-susceptible horses. Control and heaves-susceptible horses received inhalation challenges with hay dust suspension (HDS) before and after lipopolysaccharide (LPS) depletion. Heaves-susceptible horses also received inhalation challenge with HDS particulates with and without the addition of LPS and were housed in two separate dusty environments during which mould and endotoxin exposure was measured. The airway inflammatory and functional response to each challenge was measured. Depletion of endotoxin from HDS attenuated the airway neutrophilia and abrogated the airway dysfunction induced in heaves horses by inhaled HDS. The airway response was re-established by adding back LPS to the depleted HDS, confirming that the attenuation in airway response was due specifically to endotoxin depletion. Interestingly, the magnitude of alteration in airway response following endotoxin depletion and add-back was greater than that which could be attributed solely to endotoxin per se, indicating that the LPS activity was enhanced by the other dust components. Consistent with this possibility, washed particulates harvested from HDS enhanced the airway response to inhaled LPS in heaves horses. Heaves horses given two different hay/straw challenges had a significantly different severity of airway inflammation and dysfunction, despite airborne dust and endotoxin concentrations in the horses' breathing zones being similar. Although inhaled endotoxin appears not to be the only determinant of disease severity in heaves, it does contribute significantly to the induction of airway inflammation

  18. Studies on `allergoids' prepared from naturally occurring allergens

    PubMed Central

    Marsh, D. G.; Lichtenstein, L. M.; Campbell, D. H.

    1970-01-01

    The highly purified major allergenic component of rye grass pollen (Group I) was used to investigate the possibility of destroying selectively the allergenic properties of an antigen, while largely retaining its original immunizing capacities. The allergen was treated under mild conditions with formalin alone or formalin plus a reactive low molecular weight additive. Certain derivatives (allergoids) showed well over 99 per cent reduction in allergenicity, determined by the histamine released from allergic human leucocytes in vitro, but were still able to combine with rabbit antibody against native antigen. Furthermore, the allergoids stimulated production (in guinea-pigs) of appreciable amounts of antibody able to inhibit native allergen-mediated human allergic histamine release in vitro and to cross-react with native antigen by PCA tests in normal guinea-pigs. Residual allergenicity and cross-immunogenicity (by the inhibition assay) of the different formalinized derivatives varied appreciably according to the additive used in formalinization, but the cross-reactivities of the different preparations in quantitative precipitin analysis against rabbit anti-native antigen serum were similar. The residual allergenicities of individual derivatives varied by up to 1000-fold in different cell preparations, suggesting a heterogeneity of allergenic determinants. Allergoid derivatives showed no hapten-like activity in that they were unable to inhibit allergen-mediated histamine release from leucocytes. The theoretical and practical application of allergoids is discussed, including their potential usefulness in improving the immunotheraphy of atopic humans. ImagesFIG. 2 PMID:4192674

  19. Levels of house dust mite allergen in cars.

    PubMed

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

    2015-09-01

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

  20. Enhancement of systemic and sputum granulocyte response to inhaled endotoxin in people with the GSTM1 null genotype

    EPA Science Inventory

    To determine if the GSTM1 null genotype is a risk factor for increased inflammatory response to inhaled endotoxin. Methods 35 volunteers who had undergone inhalation challenge with a 20 000 endotoxin unit dose of Clinical Center Reference Endotoxin (CCRE) were genotyped for the G...