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Howard I. Maibach - One of the best experts on this subject based on the ideXlab platform.
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are topical corticoids efficacious in acute Irritant dermatitis the evidence
Dermatitis, 2020Co-Authors: Nazanin Azizi, Howard I. MaibachAbstract:Topical corticosteroid therapies are widely utilized, despite the controversial results of corticoid therapy in Irritant contact dermatitis as a local inflammatory reaction after repeated or single skin exposure to a chemical substance. Although corticoids may reduce the inflammatory response to the Irritant, their antiproliferative effects may reduce skin barrier recovery while allowing further penetration of Irritants if exposure continues. This overview reexamines the efficacy of corticosteroids in Irritant contact dermatitis therapy, and with the minimal controlled experimental data currently available, notes the need for same-in this common clinical entity.
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Anti-Irritants agents for the treatment of Irritant contact dermatitis: clinical and patent perspective.
Recent patents on inflammation & allergy drug discovery, 2012Co-Authors: Hongbo Zhai, Howard I. MaibachAbstract:This overview defines whether anti-Irritant agents, in fact, inhibit, prevent or treat Irritant contact dermatitis (ICD) in man. We performed a literature search using PubMed, EMBASE, and Scopus via the library at University of California San Francisco, and a hand search of relevant text books to investigate chemicals that can be considered anti-Irritants in either prevention or treatment. Emphasis was placed on data that included quantitative and qualitative results and that followed evidence-based dermatological guidelines. Related patents were summarized. Conflicting observations summarized here suggest well controlled, but often arduous, field type studies are required for confirmation.
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Irritant contact dermatitis: effect of age
Cutaneous and ocular toxicology, 2011Co-Authors: Hongbo Zhai, Susan R. Meier-davis, Brenda Cayme, Jutaro Shudo, Howard I. MaibachAbstract:Knowledge on age-relationship to Irritant contact dermatitis (ICD) remains of interest. We searched for articles and textbooks on age-relationship to ICD and evaluated relevant data. Irritant response may be enhanced in children and decline with increasing age. In general, older skin reacts more slowly and with less intensity to Irritants when compared with young skin. Such age-related changes may depend: (i) on differences in percutaneous penetration in old and young skin, and/or on (ii) differences in the microcirculatory efficiency, which serves as the route by which inflammatory cells make their way to the site of inflammation. Additionally, stratum corneum turnover time increases with age which means that an Irritant remains longer on the skin; a compromised cutaneous blood vessel network with ageing may lead to a decreased inflammatory response, decreased absorption and decreased clearance. In conclusion, age-related differences of ICD are present despite some conflicting data. Investigations elucid...
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Chapter 23 – Irritant Dermatitis
Hayes' Handbook of Pesticide Toxicology, 2010Co-Authors: Lisa E. Maier, Howard I. Maibach, Michael A. O’malleyAbstract:Publisher Summary This chapter discusses the factors influencing Irritant potential, delineates general clinical presentations of Irritant dermatitis, and addresses workup and treatment. In addition, it addresses methods of evaluating a chemical's Irritant potential and discusses the irritation potential of some agricultural chemicals and plants. Irritant contact dermatitis (ICD) is defined as nonimmunologic skin inflammation after contact to a substance or physical factor. Although epidemiologic data are scarce, ICD appears to be an important cause of occupational and nonoccupational skin disease. Various factors influence a chemical's Irritant potential. Intrinsic molecular properties such as molecular structure, size, ionization state, lipid solubility, and pKa determine the chemical's interaction with the skin barrier and epidermal cells. Irritant potential is also dependent on the molar concentration and volume and duration of the exposure. Physical factors such as extremes of temperature and humidity, as well as mechanical factors such as occlusion and friction, can enhance irritation of chemicals or act as Irritants. Endogenous factors such as age, anatomical site, preexisting dermatologic conditions, and genetic background may influence an individual's predisposition to Irritant dermatitis. There is a decreased susceptibility of irritation with increasing age, with children younger than 8 years being most susceptible to skin irritation. Few human studies exist, and new studies are currently inhibited by the U.S. Environmental Protection Agency's ethics system. Lastly, epidemiologic data that are so helpful for many contact allergens remain scarce for agricultural Irritants. The techniques and assays are efficient; however, a regulatory system that promotes developing and registering relevant data in this arena is lacking.
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Irritants in combination with a synergistic or additive effect on the skin response an overview of tandem irritation studies
Contact Dermatitis, 2006Co-Authors: Francisca Kartono, Howard I. MaibachAbstract:Sodium lauryl sulfate (SLS) has often been chosen as a model for Irritant contact dermatitis (ICD) to study the effect of Irritants in combination (1–14). Recently ‘tandem’, or sequential, exposures with SLS have been performed to study the mechanism of skin barrier impairment in ICD (1–6, 15). The assessment of reactions have been documented with visual scoring, transepidermal water loss (TEWL), skin colour reflectance measurements, skin blood flow; among which TEWL has been noted as the most sensitive value (16). The matched control groups were treated with either a single exposure to a single Irritant or in tandem with the same Irritant repeatedly. Synergistic and additive effects have been reported for various tandem pairs of Irritants, however, the mechanism for both remains unclear. The results of tandem irritation studies were evaluated to define and investigate the responses produced and deduce a possible mechanism of action. Clinical ramifications, albeit complex, are discussed.
Nicole Le Moual - One of the best experts on this subject based on the ideXlab platform.
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Domestic exposure to Irritant cleaning agents and asthma in women
Environment International, 2020Co-Authors: Pierre Lemire, Orianne Dumas, Sébastien Chanoine, Sofia Temam, Gianluca Severi, Marie-christine Boutron-ruault, Jan-paul Zock, Valérie Siroux, Raphaëlle Varraso, Nicole Le MoualAbstract:An adverse role of frequent domestic use of cleaning agents, especially in spray form, on asthma has been reported. However, sparse studies have investigated respiratory health effects of chronic domestic exposure to Irritant cleaning agents. This study aims to investigate associations between weekly use of Irritant domestic cleaning products and current allergic and non-allergic asthma in a large cohort of elderly women. We used data from the Asthma-E3N nested case-control study on asthma (n = 19,404 women, response rate: 91%, 2011), in which participants completed standardized questionnaires on asthma and on the use of domestic cleaning products including Irritants (bleach, ammonia, solvents and acids). Allergic multimorbidity in asthma was assessed from allergic-related medications recorded in drug refunds database. The association between use of Irritants and current asthma was estimated by logistic regression (current vs. never asthma) and multinomial logistic regression (never asthma, non-allergic asthma, allergic asthma) adjusted on age, smoking status and body mass index (BMI). In the 12,758 women included in the analysis (mean age: 70 years, current smokers: 4%, BMI ≥ 25 kg/m2: 32%, low education: 11%, current asthma: 23%), 47% reported weekly use of at least one Irritant cleaning product at home. Weekly use of Irritant products was associated with a higher risk of current asthma (adjusted Odds-Ratio: 1.17, 1.07-1.27). A statistically significant dose-response association was reported (p trend < 0.0001), with both the number of Irritant products used weekly (1 Irritant: 1.12, 1.02-1.23; 2 Irritants: 1.21, 1.05-1.39; 3 Irritants or more: 2.08, 1.57-2.75) and the frequency of use (1-3 days/week: 1.12, 1.02-1.23; 4-7 days/week: 1.41,1.22-1.64). A dose-response association was observed with the frequency of products used (p trend < 0.05), for both non-allergic (4-7 days/week: 1.27, 1.02-1.57) and allergic asthma (1.52, 1.27-1.82). In conclusion, weekly use of common cleaning Irritants was associated with an increased risk of current asthma, whatever the allergic status.
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domestic exposure to Irritant cleaning agents and asthma in women
Environment International, 2020Co-Authors: Pierre Lemire, Orianne Dumas, Sébastien Chanoine, Sofia Temam, Gianluca Severi, Jan-paul Zock, Valérie Siroux, Raphaëlle Varraso, Marie Christine Boutronruault, Nicole Le MoualAbstract:Abstract An adverse role of frequent domestic use of cleaning agents, especially in spray form, on asthma has been reported. However, sparse studies have investigated respiratory health effects of chronic domestic exposure to Irritant cleaning agents. This study aims to investigate associations between weekly use of Irritant domestic cleaning products and current allergic and non-allergic asthma in a large cohort of elderly women. We used data from the Asthma-E3N nested case-control study on asthma (n = 19,404 women, response rate: 91%, 2011), in which participants completed standardized questionnaires on asthma and on the use of domestic cleaning products including Irritants (bleach, ammonia, solvents and acids). Allergic multimorbidity in asthma was assessed from allergic-related medications recorded in drug refunds database. The association between use of Irritants and current asthma was estimated by logistic regression (current vs. never asthma) and multinomial logistic regression (never asthma, non-allergic asthma, allergic asthma) adjusted on age, smoking status and body mass index (BMI). In the 12,758 women included in the analysis (mean age: 70 years, current smokers: 4%, BMI ≥ 25 kg/m2: 32%, low education: 11%, current asthma: 23%), 47% reported weekly use of at least one Irritant cleaning product at home. Weekly use of Irritant products was associated with a higher risk of current asthma (adjusted Odds-Ratio: 1.17, 1.07–1.27). A statistically significant dose–response association was reported (p trend In conclusion, weekly use of common cleaning Irritants was associated with an increased risk of current asthma, whatever the allergic status.
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domestic exposure to Irritant cleaning agents and asthma in women
European Respiratory Journal, 2018Co-Authors: Pierre Lemire, Orianne Dumas, Sébastien Chanoine, Sofia Temam, Gianluca Severi, Jan-paul Zock, Valérie Siroux, Raphaëlle Varraso, Marie Christine Boutronruault, Nicole Le MoualAbstract:Background: The adverse association between domestic exposure to cleaning agents, especially in spray form, and asthma is now well documented in the literature. However, data on domestic exposure to Irritant cleaning agents are sparse. Aims: To investigate associations between usual Irritant domestic cleaning products and current asthma, in a large cohort of elderly women. Methods: In a nested case-control study on asthma (Asthma-E3N, 2011-2013, n=19404, response rate: 92%; ever asthma: 33%), women completed standardized questionnaires on asthma and frequency of use of domestic cleaning products, especially four well-identified Irritants (bleach, ammonia, decalcifiers, other acids). Associations between use of such Irritants and current asthma were adjusted for age, smoking status, body mass index (BMI) and education level. Results: The 12758 women included in the analysis were on average 70 years old (current smokers: 4%, BMI≥ 25: 29%, low education: 11%, current asthma: 23%). No association was found between weekly use of bleach alone and current asthma (OR 95%CI: 1.09[0.97-1.21]). However, a strong association was observed for concomitant weekly use of several cleaning agents (p trend Conclusions: Results suggested an increased risk of current asthma with use of multiple Irritant cleaning agents at home. In further investigations, we will more specifically examine their associations with non-allergic asthma.
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Do chronic workplace Irritant exposures cause asthma
Current opinion in allergy and clinical immunology, 2016Co-Authors: Orianne Dumas, Nicole Le MoualAbstract:The present review summarizes the recent literature on the relation between chronic workplace Irritant exposures and asthma, focusing on exposures of low to moderate levels. We discuss results from epidemiological surveys, potential biological mechanisms, and needs for further research. These aspects are largely illustrated by studies on exposure to cleaning products. Recent results from nine population-based and workplace-based epidemiological studies, mostly cross-sectional, found an increased risk of both new-onset and work-exacerbated asthma among participants exposed to moderate level of Irritants and/or cleaning products. Evidence of a causal effect of chronic workplace Irritant exposure in new-onset asthma remains limited, mainly because of a lack of longitudinal studies and the difficulty to evaluate Irritant exposures. However, recent epidemiological studies strengthen the evidence of an effect of chronic exposure to Irritants in work-related asthma. The underlying mechanism remains unknown but may be related to oxidative stress, neurogenic inflammation and dual Irritant and adjuvant effects. However, disentangling chronic Irritant effects from either acute Irritant-induced asthma or immunological low molecular weight agent-induced asthma is difficult for some agents. Further research is needed to improve assessment of Irritant exposures and identify biomarkers.
Heather P. Lampel - One of the best experts on this subject based on the ideXlab platform.
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Review of Occupational Contact Dermatitis—Top Allergens, Best Avoidance Measures
Current Treatment Options in Allergy, 2015Co-Authors: Rosie Qin, Heather P. LampelAbstract:Opinion statementOccupational contact dermatitis accounts for a significant proportion of occupational disease. Although dermatitis can occur anywhere on the body, hands are the most frequently affected location. Long-term or repetitive exposure to allergens and Irritants can lead to chronic dermatitis resulting in significant reduction in quality of life. The first-line treatment for both Irritant and allergic contact dermatitis is Irritant and allergen avoidance. Modification of diet and lifestyle may be necessary to reduce exposures to certain substances. Well-established and user-friendly electronic databases are now available to help patients with avoidance of allergens and their cross-reactors by elimination or substitution. Barrier creams are another method of reducing contact with Irritants, although their efficacy is not well proven. When avoidance measures fail, second-line treatments include topical and oral pharmacologic measures and interventional procedures including UV therapy. Emerging therapies for the treatment of allergic contact dermatitis aim to reduce inflammation via targeted alteration of cytokine pathways. Finally, in cases of occupational contact dermatitis refractive to treatment, a change of job task or even occupation may become necessary.
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Review of Occupational Contact Dermatitis—Top Allergens, Best Avoidance Measures
Current Treatment Options in Allergy, 2015Co-Authors: Heather P. LampelAbstract:Occupational contact dermatitis accounts for a significant proportion of occupational disease. Although dermatitis can occur anywhere on the body, hands are the most frequently affected location. Long-term or repetitive exposure to allergens and Irritants can lead to chronic dermatitis resulting in significant reduction in quality of life. The first-line treatment for both Irritant and allergic contact dermatitis is Irritant and allergen avoidance. Modification of diet and lifestyle may be necessary to reduce exposures to certain substances. Well-established and user-friendly electronic databases are now available to help patients with avoidance of allergens and their cross-reactors by elimination or substitution. Barrier creams are another method of reducing contact with Irritants, although their efficacy is not well proven. When avoidance measures fail, second-line treatments include topical and oral pharmacologic measures and interventional procedures including UV therapy. Emerging therapies for the treatment of allergic contact dermatitis aim to reduce inflammation via targeted alteration of cytokine pathways. Finally, in cases of occupational contact dermatitis refractive to treatment, a change of job task or even occupation may become necessary.
Cindy A Ryan - One of the best experts on this subject based on the ideXlab platform.
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use of a b cell marker b220 to discriminate between allergens and Irritants in the local lymph node assay
Toxicological Sciences, 2002Co-Authors: Frank G Gerberick, Rebecca Jane Dearman, Ben C. Hulette, Joel G Chaney, Lynn W Cruse, Cindy A Ryan, Robert A Skinner, Ian KimberAbstract:It has been shown that exposure of mice to contact allergens induces B cell activation in the draining lymph nodes (DLN), as seen by an increase in the percentage of B220+ or IgG/IgM+ cells. We have now examined whether the measurement of the percentage of B220+ cells could be used as an alternative or supplementary endpoint for the local lymph node assay (LLNA) to differentiate between allergenic responses and those few Irritants that induce low-level proliferation in the DLN. Mice were treated on the ears, daily for 3 consecutive days, with various allergens (1-chloro-2,4-dinitrobenzene, alpha-hexylcinnamaldehyde, trinitrochlorobenzene, isoeugenol, and eugenol) or Irritants (benzalkonium chloride, methyl salicylate, salicylic acid, and sodium lauryl sulfate). The DLN were excised 72 h following the final topical treatment, and the cells were prepared for B220 analysis using flow cytometry. The percentage of B220+ cells in lymph nodes derived from test and vehicle-treated animals was determined for 5 allergens and 4 Irritants tested in multiple experiments (n = 3 to 17). As expected, the percentage of B220+ B cells was increased with each of the allergens tested, whereas Irritant treatment did not cause similar increases. Moreover, the method was reproducible. For example, the strong allergen, 1-chloro-2,4-dinitrobenzene and the weak allergen, alpha-hexylcinnamaldehyde were identified as allergens in 17 of 17 and in 12 of 13 experiments, respectively. The percentage of B220 values for each chemical treatment (41 observations for allergens; 28 observations for Irritants) versus the percentage of B220 values for the concurrent vehicle controls were plotted, and a classification tree model was developed that defined a B220 test:vehicle ratio cutoff of 1.25 for discriminating between allergens (>1.25) and Irritants (<1.25). Using this B220 test:vehicle ratio of 1.25 in 93% of the 69 independent observations made, the allergens and Irritants tested were identified correctly. Finally, to evaluate the performance of this model in a second independent laboratory, 3 allergens and 2 Irritants were tested. Each of the allergens and Irritants were classified correctly using the B220 test:vehicle ratio cutoff of 1.25. These data demonstrate that analysis of B220 expression in DLN may be useful in differentiating between allergen and Irritant responses induced in chemically treated mice.
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local lymph node assay differentiating allergic and Irritant responses using flow cytometry
Methods, 1999Co-Authors: Frank G Gerberick, L W Cruse, Cindy A RyanAbstract:Abstract The murine local lymph node assay (LLNA) is a method for assessing the contact sensitization potential of chemicals. Based on events that occur during the induction phase of a contact sensitization response, the LLNA measures the in vivo proliferation of cells in the draining lymph nodes (DLNs) of mice following topical exposure to chemicals. In terms of predictive identification of important skin sensitizers, the LLNA has been shown to be at least as sensitive as, and much more reliable than, current guinea pig tests. However, proliferation has also been observed following treatment with some Irritants. In an attempt to distinguish allergic from Irritant-induced proliferation, flow cytometric techniques have been used to examine the phenotype of lymphocyte subsets in the DLNs as well as markers of T-lymphocyte activation and memory. Mice were treated on the ears for 3 consecutive days with allergens or Irritants. The DLNs were harvested 72 h after the final treatment. Single-cell suspensions were prepared, counted, and stained for analysis of the percentages of T cells and B cells and T-cell expression of two adhesion molecules that have been associated with differentiating naive and activated/memory T cells, CD62L (L-selectin) and CD44 (H-cam). Increases in lymph node cellularity were observed in both allergen- and Irritant-treated mice relative to naive and vehicle-treated animals. Mice treated with allergens showed a preferential increase in the percentage of B220+ B cells compared with Irritant-treated mice. Treatment with allergens, but not Irritants, resulted in a selective increase in the percentages of CD4+ and CD8+ cells expressing the T-cell activation/memory phenotype CD62LloCD44hi. Taken together, flow cytometric analysis of cell phenotype and expression of T-cell activation/memory markers may provide important information for differentiating allergen- and Irritant-induced proliferative responses in the DLNs of chemically treated mice.
Frank G Gerberick - One of the best experts on this subject based on the ideXlab platform.
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use of a b cell marker b220 to discriminate between allergens and Irritants in the local lymph node assay
Toxicological Sciences, 2002Co-Authors: Frank G Gerberick, Rebecca Jane Dearman, Ben C. Hulette, Joel G Chaney, Lynn W Cruse, Cindy A Ryan, Robert A Skinner, Ian KimberAbstract:It has been shown that exposure of mice to contact allergens induces B cell activation in the draining lymph nodes (DLN), as seen by an increase in the percentage of B220+ or IgG/IgM+ cells. We have now examined whether the measurement of the percentage of B220+ cells could be used as an alternative or supplementary endpoint for the local lymph node assay (LLNA) to differentiate between allergenic responses and those few Irritants that induce low-level proliferation in the DLN. Mice were treated on the ears, daily for 3 consecutive days, with various allergens (1-chloro-2,4-dinitrobenzene, alpha-hexylcinnamaldehyde, trinitrochlorobenzene, isoeugenol, and eugenol) or Irritants (benzalkonium chloride, methyl salicylate, salicylic acid, and sodium lauryl sulfate). The DLN were excised 72 h following the final topical treatment, and the cells were prepared for B220 analysis using flow cytometry. The percentage of B220+ cells in lymph nodes derived from test and vehicle-treated animals was determined for 5 allergens and 4 Irritants tested in multiple experiments (n = 3 to 17). As expected, the percentage of B220+ B cells was increased with each of the allergens tested, whereas Irritant treatment did not cause similar increases. Moreover, the method was reproducible. For example, the strong allergen, 1-chloro-2,4-dinitrobenzene and the weak allergen, alpha-hexylcinnamaldehyde were identified as allergens in 17 of 17 and in 12 of 13 experiments, respectively. The percentage of B220 values for each chemical treatment (41 observations for allergens; 28 observations for Irritants) versus the percentage of B220 values for the concurrent vehicle controls were plotted, and a classification tree model was developed that defined a B220 test:vehicle ratio cutoff of 1.25 for discriminating between allergens (>1.25) and Irritants (<1.25). Using this B220 test:vehicle ratio of 1.25 in 93% of the 69 independent observations made, the allergens and Irritants tested were identified correctly. Finally, to evaluate the performance of this model in a second independent laboratory, 3 allergens and 2 Irritants were tested. Each of the allergens and Irritants were classified correctly using the B220 test:vehicle ratio cutoff of 1.25. These data demonstrate that analysis of B220 expression in DLN may be useful in differentiating between allergen and Irritant responses induced in chemically treated mice.
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local lymph node assay differentiating allergic and Irritant responses using flow cytometry
Methods, 1999Co-Authors: Frank G Gerberick, L W Cruse, Cindy A RyanAbstract:Abstract The murine local lymph node assay (LLNA) is a method for assessing the contact sensitization potential of chemicals. Based on events that occur during the induction phase of a contact sensitization response, the LLNA measures the in vivo proliferation of cells in the draining lymph nodes (DLNs) of mice following topical exposure to chemicals. In terms of predictive identification of important skin sensitizers, the LLNA has been shown to be at least as sensitive as, and much more reliable than, current guinea pig tests. However, proliferation has also been observed following treatment with some Irritants. In an attempt to distinguish allergic from Irritant-induced proliferation, flow cytometric techniques have been used to examine the phenotype of lymphocyte subsets in the DLNs as well as markers of T-lymphocyte activation and memory. Mice were treated on the ears for 3 consecutive days with allergens or Irritants. The DLNs were harvested 72 h after the final treatment. Single-cell suspensions were prepared, counted, and stained for analysis of the percentages of T cells and B cells and T-cell expression of two adhesion molecules that have been associated with differentiating naive and activated/memory T cells, CD62L (L-selectin) and CD44 (H-cam). Increases in lymph node cellularity were observed in both allergen- and Irritant-treated mice relative to naive and vehicle-treated animals. Mice treated with allergens showed a preferential increase in the percentage of B220+ B cells compared with Irritant-treated mice. Treatment with allergens, but not Irritants, resulted in a selective increase in the percentages of CD4+ and CD8+ cells expressing the T-cell activation/memory phenotype CD62LloCD44hi. Taken together, flow cytometric analysis of cell phenotype and expression of T-cell activation/memory markers may provide important information for differentiating allergen- and Irritant-induced proliferative responses in the DLNs of chemically treated mice.
