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Sample records for skin test reactivity

  1. Reactivity of allergy skin test in healthy volunteers

    PubMed Central

    Supakthanasiri, Phisit; Klaewsongkram, Jettanong; Chantaphakul, Hiroshi

    2014-01-01

    INTRODUCTION Healthy individuals may be exposed and sensitised to allergens, and have a positive response to a skin prick test despite being asymptomatic. The objectives of this study were to evaluate the prevalence of atopic sensitisation and identify the reactivity of healthy volunteers to common aeroallergens. METHODS Healthy volunteers with no known allergic symptoms were recruited in this study. All volunteers were scheduled to undergo a skin prick test with 16 common aeroallergens that were previously identified among atopic patients. RESULTS A total of 100 volunteers (mean age 28 years) were enrolled in this study. 42 volunteers had positive skin prick tests for at least one allergen. The median number of sensitised allergen was 2 (range 1–7). Volunteers with positive skin tests (n = 42) were younger than those with negative skin tests (n = 58) (mean age 25.5 vs. 29.2 years; p < 0.05). The group with positive skin tests also had a higher proportion of males (57.1% vs. 31.0%; p < 0.01) and first-degree relatives with a history of atopic diseases (31.0% vs. 10.3%; p < 0.05). The most common sensitised allergens in these healthy asymptomatic volunteers were mite (n = 33), house dust (n = 23) and American cockroach (n = 20). CONCLUSION In this study, up to 42% of healthy volunteers, particularly those with a family history of atopy, were sensitised to allergens. Reactivity of the skin test without allergic symptoms, however, does not indicate allergic disease. Therefore, the skin test should only be indicated in atopic symptomatic individuals. PMID:24452975

  2. Allergic skin test reactivity to marijuana in the Southwest.

    PubMed

    Freeman, G L

    1983-06-01

    In a general allergy consultation practice in Arizona and western New Mexico, 129 patients were tested for immediate hypersensitivity skin test reactivity to marijuana pollen and tobacco leaf, as well as to a battery of other antigens. In all, 90 patients were diagnosed as allergic (atopic) and, of these, 63 (70 percent) were found to be skin test reactive to marijuana pollen and 18 (20 percent) to tobacco leaf. The incidence of skin test reactivity to marijuana was not significantly different for persons living at low, middle or high elevations throughout the Southwest. Marijuana sensitivity occurred in patients who were, in general, also sensitive to a variety of other airborne plant pollens. There was no close correlation, however, between sensitivity to marijuana pollen and sensitivity to pollens from elm, mulberry, hop and stinging nettle, which are botanically related to marijuana. The data suggest that marijuana pollen may be a relatively common airborne pollen pollutant in the Southwest, allergic persons being sensitized through inhalation. If this is confirmed by further studies, then clinical investigation of marijuana hyposensitization (immunotherapy) may be warranted. This is in contrast to tobacco allergy for which simple avoidance is recommended. PMID:6613109

  3. Allergic Skin Test Reactivity to Marijuana in the Southwest

    PubMed Central

    Freeman, Geraldine L.

    1983-01-01

    In a general allergy consultation practice in Arizona and western New Mexico, 129 patients were tested for immediate hypersensitivity skin test reactivity to marijuana pollen and tobacco leaf, as well as to a battery of other antigens. In all, 90 patients were diagnosed as allergic (atopic) and, of these, 63 (70 percent) were found to be skin test reactive to marijuana pollen and 18 (20 percent) to tobacco leaf. The incidence of skin test reactivity to marijuana was not significantly different for persons living at low, middle or high elevations throughout the Southwest. Marijuana sensitivity occurred in patients who were, in general, also sensitive to a variety of other airborne plant pollens. There was no close correlation, however, between sensitivity to marijuana pollen and sensitivity to pollens from elm, mulberry, hop and stinging nettle, which are botanically related to marijuana. The data suggest that marijuana pollen may be a relatively common airborne pollen pollutant in the Southwest, allergic persons being sensitized through inhalation. If this is confirmed by further studies, then clinical investigation of marijuana hyposensitization (immunotherapy) may be warranted. This is in contrast to tobacco allergy for which simple avoidance is recommended. PMID:6613109

  4. Allergen skin test reactivities among asthmatic Thai children.

    PubMed

    Kongpanichkul, A; Vichyanond, P; Tuchinda, M

    1997-02-01

    Skin prick tests with 14 selected local aeroallergens were performed on 100 asthmatic children aged 0-16 years attending the Pediatric Allergy Clinic, Faculty of Medicine, Siriraj Hospital. The 14 allergens included Dermatophagoides farinae, Dermatophagoides pteronyssinus, American cockroach (Periplaneta americana), Johnson grass (Sorghum halopense), Cladosporium clarosporoides, Alternaria tenuis, Penicillium mix, Aspergillus mix, cat dander, dog dander, milk, egg white, soy and shrimp. Positive skin test reactivity was defined as a mean wheal diameter > or = 3 mm at the 20 minute reading. There were 68 males and 32 females. Their ages were between 0-2 years (n = 1), 2-5 years (n = 19), 5-10 years (n = 49) and 10-16 years (n = 31). Of all the subjects, 22 were classified as having mild asthma, 74 with moderate asthma and 4 with severe asthma. At least one skin prick test was positive in 74 subjects (74%) and two positive tests in 66 subjects (66%). The prevalence of sensitization to various allergens was as follows; Dermatophagoides pteronyssinus 67%, Dermatophagoides farinae 62%, American cockroach 44%, shrimp 14%, Johnson grass 14%, cat dander 10%, Alternaria 7%, Cladosporium 7%, dog dander 5%, soy 4%, Penicillium 3%, Aspergillus 2%, milk 2% and egg white 1%. The wheal size to Dermatophagoides pteronyssinus did not correlate with age. In this group of asthmatic Thai children, house dust mites are the most important allergen causing sensitization. PMID:9078689

  5. PPD skin test

    MedlinePlus

    Purified protein derivative standard; TB skin test; Tuberculin skin test; Mantoux test ... Berger BJ. Mantoux skin test (PPD test, purified protein derivative test, Tb test, tuberculin skin test, TST, ...

  6. Allergy testing - skin

    MedlinePlus

    Patch tests - allergy; Scratch tests - allergy; Skin tests - allergy; RAST test ... There are three common methods of allergy skin testing. The skin prick test involves: Placing a small amount of substances that may be causing your symptoms on the skin, ...

  7. Tuberculin skin test reactivity is dependent on host genetic background in Colombian tuberculosis household contacts.

    PubMed

    Cobat, Aurélie; Barrera, Luis F; Henao, Hanna; Arbeláez, Patricia; Abel, Laurent; García, Luis F; Schurr, Erwin; Alcaïs, Alexandre

    2012-04-01

    The tuberculin skin test (TST) measures the intensity of antimycobacterial acquired immunity and is used to diagnose latent infection with Mycobacterium tuberculosis. We report evidence for a codominant gene explaining ∼65% of the TST variability. Disregarding the host genetic background may lead to misclassifications of TST-based diagnosis of latent M. tuberculosis infection. PMID:22291100

  8. Skin testing of gallic acid-based hair dye in paraphenylenediamine/paratoluenediamine-reactive patients.

    PubMed

    Choi, Yunseok; Lee, Joon Ho; Kwon, Hyok Bu; An, Susun; Lee, Ai-Young

    2016-07-01

    Incidence of allergic contact dermatitis (ACD) to para-phenylenediamine (PPD)/paratoluenediamine (PTD) hair dyes is increasing. Hair dyes utilizing gallic acid (GA) may be a safe alternative. However, pretesting is recommended. We investigated the contact sensitivity to ingredients of a dye product; GA, monoethanolamine thioglycolate (MT), l-cystein and ferrous sulfate, and an appropriate pretest method in 31 patients reactive to PPD and/or PTD. An open test was performed with the test dye following the patch test. Subsequently, a use test was performed twice, with a 4-week interval. One subject showed a positive reaction to ferrous sulfate in the patch test. Another subject reacted to the first compound alone in the open test. Thirteen subjects manifesting cutaneous lesions from previous regular hair dyeing, showed reactions at the first use of the test dye; and six had reactions with reduced severity at the second test. GA and MT are safe for use in ACD patients reactive to PPD and/or PTD. For predicting contact allergy to hair dyes, the open test appeared to be a better pretest method than the patch test. PMID:26663148

  9. 5-HTTLPR Expression Outside the Skin: An Experimental Test of the Emotional Reactivity Hypothesis in Children

    PubMed Central

    Weeland, Joyce; Slagt, Meike; Brummelman, Eddie; Matthys, Walter; de Castro, Bram Orobio; Overbeek, Geertjan

    2015-01-01

    Background There is increasing evidence that variation in the promoter region of the serotonin transporter gene SLC6A4 (i.e., the 5-HTTLPR polymorphism) moderates the impact of environmental stressors on child psychopathology. Emotional reactivity −the intensity of an individual’s response to other’s emotions− has been put forward as a possible mechanism underlying these gene-by-environment interactions (i.e., G×E). Compared to children homozygous for the L-allele (LL-genotypes), children carrying an S-allele (SS/SL-genotypes), specifically when they have been frequently exposed to negative emotions in the family environment, might be more emotionally reactive and therefore more susceptible to affective environmental stressors. However, the association between 5-HTTLPR and emotional reactivity in children has not yet been empirically tested. Therefore, the goal of this study was to test this association in a large-scale experiment. Methods Children (N = 521, 52.5% boys, Mage = 9.72 years) were genotyped and randomly assigned to happy, angry or neutral dynamic facial expressions and vocalizations. Motor and affective emotional reactivity were assessed through children’s self-reported negative and positive affect (n = 460) and facial electromyography activity (i.e., fEMG: the zygomaticus or “smile” muscle and the corrugator or “frown” muscle, n = 403). Parents reported on their negative and positive parenting behaviors. Results Children mimicked and experienced the emotion they were exposed to. However, neither motor reactivity nor affective reactivity to these emotions depended on children’s 5-HTTLPR genotype: SS/SL-genotypes did not manifest any stronger response to emotional stimuli than LL-genotypes. This finding remained the same when taking the broader family environment into account, controlling for kinship, age, gender and genetic ancestry, and when including a tri-allelic factor. Conclusions We found no evidence for an association

  10. Skin reactivity to metallic cobalt in patients with a positive patch test to cobalt chloride.

    PubMed

    de Fine Olivarius, F; Menné, T

    1992-10-01

    458 consecutive patients were patch tested with a metallic cobalt disc as a supplement to the standard series. 23 patients had a positive reaction to CoCl2 1% pet. Of these, 19 were tested with the cobalt disc. 11 had a positive reaction and 5 a questionable reaction. There were no positive reactions to the cobalt disc in patients with a negative patch test to CoCl2 1% pet. Patch testing with CoCl2 1% pet. diagnoses all patients with allergy to metallic cobalt, but the test method is limited by a high number of irritant and questionable reactions. PMID:1451489

  11. CSD skin test

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003385.htm CSD skin test To use the sharing features on this page, please enable JavaScript. The cat scratch disease (CSD) skin test was once used to help ...

  12. PPD skin test

    MedlinePlus

    ... is a method used to diagnose silent (latent) tuberculosis (TB) infection. PPD stands for purified protein derivative. ... derivative test, Tb test, tuberculin skin test, TST, tuberculosis test) - diagnostic. In: Chernecky CC, Berger BJ, eds. ...

  13. Sensitive skin and stratum corneum reactivity to household cleaning products.

    PubMed

    Goffin, V; Piérard-Franchimont, C; Piérard, G E

    1996-02-01

    Products intended for individuals with sensitive skin are being increasingly developed by formulators of household cleaning products. However, there is currently no consensus about the definition and recognition of the biological basis of sensitive skin. We sought to determine the relation between the nature of environmental threat perceived as aggressive by panelists, and the stratum corneum reactivity to household cleaning products as measured by the corneosurfametry test. Results indicate substantial differences in irritancy potential between proprietary products. Corneosurfametry data show significant differences in stratum corneum reactivity between, on the one hand, individuals with either non-sensitive skin or skin sensitive to climate/fabrics, and, on the other hand, individuals with detergent-sensitive skin. It is concluded that sensitive skin is not one single condition. Sound information in rating detergent-sensitive skin may be gained by corneosurfametry. PMID:8681562

  14. CSD skin test

    MedlinePlus

    The cat scratch disease (CSD) skin test was once used to help diagnose CSD. The test is no longer used today. ... LN, Welch DF, Koehler JE. Bartonella, including cat-scratch disease. In: Bennett JE, Dolin R, Blaser MJ, ...

  15. [Positive skin test and age

    PubMed

    Forte, W C; Júnior, F F; Filho, W D; Shibata, E; Henriques, L S; Mastroti, R A; Guedes, M da S

    2001-01-01

    OBJECTIVE: To evaluate positive responses to skin tests for immediate hypersensitivity to allergens in children with asthma and rhinitis at different ages. METHOD: We observed positive skin test reactivity in prick tests using fifteen allergens of same origin (total dust and Dermatophagoides sp.; Dermatophagoides pteronyssinus; Dermatophagoides farinae; Blomia tropicalis; Penicillium sp; Alternaria alternata; Cladosporium herbarium; Aspergillus fumigatus; Bermuda grass; forage grass; dog and cat epithelia; feathers; Blatella germanica and wool). We placed 713 selected patients into different age groups - Group I: 6 to 11 months; Group II: 1 to 3 years and 11 months; Group III: 4 to 8 years and 11 months; and Group IV: 9 to 15 years. We used the chi-square test for statistical analysis. RESULTS: The total significant differences between these groups were: I to II = 5; II to III = 5; II to IV = 5; III to IV = 6; I to III = 10; and I to IV = 10. CONCLUSION: Skin test reactivity is acquired progressively with age, and can be observed as early as at 12 months. Reactivity is significantly more positive from the age of 4 on. PMID:14647601

  16. Tuberculin Skin Testing

    MedlinePlus

    ... perpendicular to the long axis). How Are TST Reactions Interpreted? Skin test interpretation depends on two factors: ... among high-risk groups. What Are False-Positive Reactions? Some persons may react to the TST even ...

  17. Bifidobacterium longum lysate, a new ingredient for reactive skin.

    PubMed

    Guéniche, Audrey; Bastien, Philippe; Ovigne, Jean Marc; Kermici, Michel; Courchay, Guy; Chevalier, Veronique; Breton, Lionel; Castiel-Higounenc, Isabelle

    2010-08-01

    Reactive skin is characterized by marked sensitivity to physical (heat, cold, wind) or chemical (topically applied products) stimuli and by the impairment of the skin barrier's ability to repair itself. Several lines of evidence suggest that beyond their capacity to positively influence the composition of intestinal microbiota, some probiotic bacteria can modulate the immune system both at local and systemic levels, thereby improving immune defense mechanisms and/or down-regulating immune disorders such as allergies and intestinal inflammation. Several recent human clinical trials clearly suggest that probiotic supplementation might be beneficial to the skin. Using a probiotic lysate, Bifidobacterium longum sp. extract (BL), we demonstrated first in vitro, and then in a clinical trial, that this non-replicating bacteria form applied to the skin was able to improve sensitive skin. The effect of BL were evaluated first on two different models. Using ex vivo human skin explant model we found a statistically significant improvement versus placebo in various parameters associated with inflammation such as a decrease in vasodilation, oedema, mast cell degranulation and TNF-alpha release. Moreover, using nerve cell cultures in vitro, we showed that after 6 h of incubation in culture medium (0.3-1%), the probiotic lysate significantly inhibited capsaicin-induced CGRP release by neurones. Then, a topical cream containing the active extract was tested in a randomized, double-blind, placebo-controlled trial. Sixty-six female volunteers with reactive skin were randomly given either the cream with the bacterial extract at 10% (n = 33) or the control cream (n = 33). The volunteers applied the cream to the face, arms and legs twice a day for two months. Skin sensitivity was assessed by stinging test (lactic acid) and skin barrier recovery was evaluated by measuring trans-epidermal water loss following barrier disruption induced by repeated tape-stripping at D1, D29 and D57. The

  18. Skin, Reactive Oxygen Species, and Circadian Clocks

    PubMed Central

    Ndiaye, Mary A.; Nihal, Minakshi; Wood, Gary S.

    2014-01-01

    Abstract Significance: Skin, a complex organ and the body's first line of defense against environmental insults, plays a critical role in maintaining homeostasis in an organism. This balance is maintained through a complex network of cellular machinery and signaling events, including those regulating oxidative stress and circadian rhythms. These regulatory mechanisms have developed integral systems to protect skin cells and to signal to the rest of the body in the event of internal and environmental stresses. Recent Advances: Interestingly, several signaling pathways and many bioactive molecules have been found to be involved and even important in the regulation of oxidative stress and circadian rhythms, especially in the skin. It is becoming increasingly evident that these two regulatory systems may, in fact, be interconnected in the regulation of homeostasis. Important examples of molecules that connect the two systems include serotonin, melatonin, vitamin D, and vitamin A. Critical Issues: Excessive reactive oxygen species and/or dysregulation of antioxidant system and circadian rhythms can cause critical errors in maintaining proper barrier function and skin health, as well as overall homeostasis. Unfortunately, the modern lifestyle seems to contribute to increasing alterations in redox balance and circadian rhythms, thereby posing a critical problem for normal functioning of the living system. Future Directions: Since the oxidative stress and circadian rhythm systems seem to have areas of overlap, future research needs to be focused on defining the interactions between these two important systems. This may be especially important in the skin where both systems play critical roles in protecting the whole body. Antioxid. Redox Signal. 20, 2982–2996. PMID:24111846

  19. Thermal provocation to evaluate microvascular reactivity in human skin

    PubMed Central

    2010-01-01

    With increased interest in predictive medicine, development of a relatively noninvasive technique that can improve prediction of major clinical outcomes has gained considerable attention. Current tests that are the target of critical evaluation, such as flow-mediated vasodilation of the brachial artery and pulse-wave velocity, are specific to the larger conduit vessels. However, evidence is mounting that functional changes in the microcirculation may be an early sign of globalized microvascular dysfunction. Thus development of a test of microvascular reactivity that could be used to evaluate cardiovascular risk or response to treatment is an exciting area of innovation. This mini-review is focused on tests of microvascular reactivity to thermal stimuli in the cutaneous circulation. The skin may prove to be an ideal site for evaluation of microvascular dysfunction due to its ease of access and growing evidence that changes in skin vascular reactivity may precede overt clinical signs of disease. Evaluation of the skin blood flow response to locally applied heat has already demonstrated prognostic utility, and the response to local cooling holds promise in patients in whom cutaneous disorders are present. Whether either of these tests can be used to predict cardiovascular morbidity or mortality in a clinical setting requires further evaluation. PMID:20507974

  20. Aspergillus antigen skin test (image)

    MedlinePlus

    The aspergillus antigen skin test determines whether or not a person has been exposed to the mold aspergillus. It is performed by injecting an aspergillus antigen under the skin with a needle. After 48 ...

  1. Common aeroallergens in patients with asthma and allergic rhinitis living in southwestern part of Iran: based on skin prick test reactivity.

    PubMed

    Farrokhi, Shokrollah; Gheybi, Mohammad Kazzem; Movahed, Ali; Tahmasebi, Rahim; Iranpour, Dariush; Fatemi, Atena; Etemadan, Razieh; Gooya, Mostafa; Zandi, Sahar; Ashourinejad, Hamid; Alavizadeh, Sara; Khoddami, Shaghayegh

    2015-04-01

    Aeroallergens continue to have a key role in the pathogenesis of asthma and allergic diseases and have recently received increased attention in medical research throughout the world. The prevalence of aeroallergens vary in different regions, depending on the type of climate. The aim of the present study was to determine prevalence of the sensitivity to aeroallergens among patients with asthma and allergic rhinitis (AR), based on skin prick test (SPT) reactivity in the province of Bushehr, Iran. In this cross-sectional study, 743 patients were enrolled. The participants had asthma and AR and reacted to at least one allergen with SPT. Skin prick test with standard extracts including house dust mites (HDMs), animal dander, molds and pollens were performed on patients according to the herbal geography of the area. The male to female ratio and mean age of the patients were 1.03 and 27.6± 15.4 year, respectively. Out of 567 patients with AR, the common aeroallergens were HDMs (88.5%), molds (82.9%), animal dander (79.5%), weeds (77.6%), trees (75.5%) and grass pollen (71.5%). Moreover, among 176 patients with asthma, the prevalence of aeroallergens were HDMs (90.5 %), molds (80.7%), animal dander (77.5%), weeds (73.3%), trees (73.3%) and grass pollen (67.9%). The sensitivity to animal dander, Chenopodium album and Russian thistle pollens were significantly associated with the severity of AR. Moreover, sensitivity to animal dander such as cat and feather of birds, cockroach, Bermuda grass and Chenopodium album pollens were significantly associated with the severity of asthma. The results of this study revealed that HDM was the most common sensitizing aeroallergen in patients with asthma and AR. Molds and animal dander as indoor allergens were also common aeroallergens. We suggest that the hot weather and ambient humidity in the region may be the main cause of the change in the pattern of SPT reactivity. PMID:25780879

  2. Allergy testing - skin

    MedlinePlus

    ... if you are allergic to bee venom or penicillin. Or it may be used if the skin ... sore, or swollen after contact with the substance Penicillin allergy Venom allergy Allergies to penicillin and closely ...

  3. Lepromin skin test

    MedlinePlus

    ... the skin up. The lump indicates that the antigen has been injected at the correct depth. The ... When the antigen is injected, there may be a slight stinging or burning. There may also be mild itching at the ...

  4. Histoplasma skin test

    MedlinePlus

    ... Histoplasma capsulatum. The fungus causes an infection called histoplasmosis. How the Test is Performed The health care ... have been exposed to the fungus that causes histoplasmosis . Normal Results No reaction (inflammation) at the site ...

  5. Seronegative reactive spondyloarthritis and the skin.

    PubMed

    Generali, Elena; Ceribelli, Angela; Massarotti, Marco; Cantarini, Luca; Selmi, Carlo

    2015-01-01

    Spondyloarthritidies represent a group of conditions affecting the axial and peripheral muscoloskeletal apparatus and are often associated with psoriasis, infections, and inflammatory bowel diseases. Other diseases included in this category are psoriatic arthritis, ankylosing spondylitis, and enteropathic arthritis. Reactive arthritis is an elusive spondyloarthritis, commonly occurring 1 to 3 weeks after a digestive or a genitourinary tract infection, in which microorganisms do not infect the joint directly. Reactive arthritis is classically characterized by large-joint arthritis, urethritis in men and cervicitis in women, and eye inflammation (usually conjunctivitis or uveitis) but encompasses numerous other symptoms and signs, including manifestations of dermatologic interest such as keratoderma blenorrhagicum and circinate balanitis. The diagnosis of reactive arthritis is clinical, and the infectious agent cannot always be identified due to disease latency after the infection. Most cases are self-limiting, but reactive arthritis may become chronic in 30% of cases. Treatment options include anti-inflammatory drugs, steroids, and sulfasalazine; biologic agents, such as tumor necrosis factor α (TNF-α) blockers, have been recently used, but there are only a few randomized clinical trials on the treatment of reactive arthritis. The effectiveness of antimicrobials needs further evaluation. PMID:26321399

  6. Skin prick testing in patients using beta-blockers: a retrospective analysis

    PubMed Central

    2010-01-01

    Rationale The use of beta-blockers is a relative contraindication in allergen skin testing yet there is a paucity of literature on adverse events in this circumstance. We examined a population of skin tested patients on beta-blockers to look for any adverse effects. Methods Charts from 2004-2008 in a single allergy clinic were reviewed for any patients taking a beta-blocker when skin tested. Data was examined for skin test reactivity, type of skin test, concomitant asthma diagnosis, allergens tested, and adverse events. Results One hundred and ninety-one patients were taking beta-blockers when skin testing occurred. Seventy-two patients had positive skin tests. No tests resulted in an adverse event. Conclusions This data demonstrates the relative safety of administrating of skin prick tests to patients on beta-blocker treatment. Larger prospective studies are needed to substantiate the findings of this study. PMID:20298514

  7. Peptide Reactivity of Isothiocyanates - Implications for Skin Allergy.

    PubMed

    Karlsson, Isabella; Samuelsson, Kristin; Ponting, David J; Törnqvist, Margareta; Ilag, Leopold L; Nilsson, Ulrika

    2016-01-01

    Skin allergy is a chronic condition that affects about 20% of the population of the western world. This disease is caused by small reactive compounds, haptens, able to penetrate into the epidermis and modify endogenous proteins, thereby triggering an immunogenic reaction. Phenyl isothiocyanate (PITC) and ethyl isothiocyanate (EITC) have been suggested to be responsible for allergic skin reactions to chloroprene rubber, the main constituent of wetsuits, orthopedic braces, and many types of sports gear. In the present work we have studied the reactivity of the isothiocyanates PITC, EITC, and tetramethylrhodamine-6-isothiocyanate (6-TRITC) toward peptides under aqueous conditions at physiological pH to gain information about the types of immunogenic complexes these compounds may form in the skin. We found that all three compounds reacted quickly with cysteine moieties. For PITC and 6-TRITC the cysteine adducts decomposed over time, while stable adducts with lysine were formed. These experimental findings were verified by DFT calculations. Our results may suggest that the latter are responsible for allergic reactions to isothiocyanates. The initial adduct formation with cysteine residues may still be of great importance as it prevents hydrolysis and facilitates the transport of isothiocyanates into epidermis where they can form stable immunogenic complexes with lysine-containing proteins. PMID:26883070

  8. Peptide Reactivity of Isothiocyanates – Implications for Skin Allergy

    PubMed Central

    Karlsson, Isabella; Samuelsson, Kristin; Ponting, David J.; Törnqvist, Margareta; Ilag, Leopold L.; Nilsson, Ulrika

    2016-01-01

    Skin allergy is a chronic condition that affects about 20% of the population of the western world. This disease is caused by small reactive compounds, haptens, able to penetrate into the epidermis and modify endogenous proteins, thereby triggering an immunogenic reaction. Phenyl isothiocyanate (PITC) and ethyl isothiocyanate (EITC) have been suggested to be responsible for allergic skin reactions to chloroprene rubber, the main constituent of wetsuits, orthopedic braces, and many types of sports gear. In the present work we have studied the reactivity of the isothiocyanates PITC, EITC, and tetramethylrhodamine-6-isothiocyanate (6-TRITC) toward peptides under aqueous conditions at physiological pH to gain information about the types of immunogenic complexes these compounds may form in the skin. We found that all three compounds reacted quickly with cysteine moieties. For PITC and 6-TRITC the cysteine adducts decomposed over time, while stable adducts with lysine were formed. These experimental findings were verified by DFT calculations. Our results may suggest that the latter are responsible for allergic reactions to isothiocyanates. The initial adduct formation with cysteine residues may still be of great importance as it prevents hydrolysis and facilitates the transport of isothiocyanates into epidermis where they can form stable immunogenic complexes with lysine-containing proteins. PMID:26883070

  9. C-Reactive Protein (CRP) Test

    MedlinePlus

    ... Home Visit Global Sites Search Help? C-Reactive Protein Share this page: Was this page helpful? Also known as: CRP Formal name: C-Reactive Protein Related tests: ESR , Complement , Procalcitonin , ANA , Rheumatoid Factor ...

  10. Reliability of skin testing as a measure of nutritional state

    SciTech Connect

    Forse, R.A.; Christou, N.; Meakins, J.L.; MacLean, L.D.; Shizgal, H.M.

    1981-10-01

    The reliability of skin testing to assess the nutritional state was evaluated in 257 patients who received total parenteral nutrition (TPN). The nutritional state was assessed by determining body composition, by multiple-isotope dilution. Immunocompetence was simultaneously evaluated by skin testing with five recall antigens. These measurements were carried out before and at two-week intervals during TPN. A statistically significant relationship existed between the response to skin testing and the nutritional state. A body composition consistent with malnutrition was present in the anergic patients, while body composition was normal in the patients who reacted normally to skin testing. However, a considerable overlap existed as 43% of the reactive patients were malnourished, and 21% of the anergic patients were normally nourished. Thirty-seven (43%) of the 86 anergic patients converted and became reactive during TPN, and their body composition improved significantly. The remaining 49 anergic patients (57%) did not convert, and their body composition did not change despite similar nutritional support. The principal difference between the two groups of anergic patients was the nature of the therapy administered. In the anergic patients who converted, therapy was aggressive and appropriate, and clinical improvement occurred in 23 (62.2%) of the patients, with a mortality of 5.4%. In the 49 patients who remained anergic, therapy was often inappropriate or unsuccessful, with clinical improvement in only three (6.1%) of the patients and a mortality of 42.8%. The data demonstrated a significant relationship between the response to skin testing and the nutritional state. However, because of the wide overlap, skin testing does not accurately assess a person's nutritional state. The persistence of the anergic state is indicative of a lack of response to therapy.

  11. Effect of reactive skin decontamination lotion on skin wound healing in laboratory rats.

    PubMed

    Walters, Thomas J; Kauvar, David S; Reeder, Joanna; Baer, David G

    2007-03-01

    Reactive skin decontamination lotion (RSDL) is a proposed replacement for the existing skin and equipment decontamination kit. Because RSDL may need to be used to decontaminate wounded personnel, we conducted an assessment of the effect of this agent on wound healing. A skin incision model using male Sprague Dawley rats (n = 19 rats/group) was used. A 7.0-cm incision was made through the skin, and RSDL was (experimental group) or was not (control group) applied to the open wound; the wound edges were then approximated with sutures. Seven days later, animals were euthanized and wound samples were taken. Healing was assessed by measuring mechanical strength, collagen content, and histological appearance. RSDL-treated wounds had 23% lower tensile strength (p < 0.05) and 11% lower collagen content (p < 0.05) than did the untreated control wounds. Histological assessments did not differ significantly between groups. The results of this investigation demonstrate that the application of RSDL directly to an open wound impairs wound strength and decreases collagen content in the early phases of wound healing. This may have clinical implications for the treatment and outcomes of chemical casualty combat trauma. PMID:17436779

  12. Prostanoids are not involved in postocclusive reactive hyperaemia in human skin.

    PubMed

    Hellmann, Marcin; Gaillard-Bigot, Florence; Roustit, Matthieu; Cracowski, Jean-Luc

    2015-10-01

    Several mediators contribute to postocclusive reactive hyperaemia (PORH) in the skin, including sensory nerves and endothelium-derived hyperpolarizing factors. The main objective of this study was to investigate the specific involvement of prostanoids in human skin PORH. We tested the effect of the inhibition of cyclo-oxygenases (COX) by 4 mm ketoprofen, infused through microdialysis fibers inserted into the healthy volunteers forearm skin, following 5 min brachial artery occlusion. Skin microvascular blood flux was recorded using two-dimensional Laser Speckle Contrast Imaging. Maximal cutaneous vascular conductance (CVCmax ) was obtained following the perfusion of 29 mm sodium nitroprusside. A systematic review of the effects of COX inhibitors on skin peak PORH was also performed. We observed no significant difference between ketoprofen and placebo for the PORH peak (78 ± 8 and 71 ± 19% CVCmax , respectively) and area under the curve (2951 ± 721 and 2490 ± 936% CVCmax .s). A meta-analysis showed a substantial heterogeneity between studies, with overall a neutral effect of COX inhibition on peak PORH. Cyclo-oxygenase inhibition does not alter skin PORH, suggesting no involvement of prostanoids in cutaneous postocclusive vasodilatation in healthy humans. PMID:26194355

  13. Randomised double-blind placebo-controlled study of the effect of Lactobacillus paracasei NCC 2461 on skin reactivity.

    PubMed

    Gueniche, A; Philippe, D; Bastien, P; Reuteler, G; Blum, S; Castiel-Higounenc, I; Breton, L; Benyacoub, J

    2014-06-01

    In recent decades, the prevalence of subjects with reactive skin has considerably increased in industrialised countries. 50% of women and 30% of men report cutaneous discomfort classified under reactive/sensitive skin. Several topical approaches have been proposed, in particular through improvement of galenic forms or protection of epidermal surface. We propose to act differently, deeply from inside the body via an innovative nutritional approach. To this purpose, Lactobacillus paracasei NCC 2461 (ST11) was selected because of its specific beneficial skin properties discovered in in vitro studies, i.e. diminution of neurogenic inflammation and promotion of the recovery of skin barrier function. We designed a randomised double-blind placebo-controlled clinical study with a two-month supplementation in two female treatment groups (n=32 per group). A capsaicin test was performed to monitor the time course of skin sensitivity. Moreover, transepidermal water loss was assessed to analyse the rate of skin barrier function recovery; dryness of the leg and roughness of the cheeks was investigated by a dermatologist as well as by self-assessment. The results of the present clinical trial show that oral supplementation with the probiotic decreases skin sensitivity and increases the rate of barrier function recovery. Thus, the data provide evidence that daily intake of ST11 could improve reactive skin condition. PMID:24322879

  14. Skin Prick Test in Patients with Chronic Allergic Skin Disorders

    PubMed Central

    Bains, Pooja; Dogra, Alka

    2015-01-01

    Background: Chronic allergic skin disorders are the inflammatory and proliferative conditions in which both genetic and environmental factors play important roles. Chronic idiopathic urticaria (CIU) and atopic dermatitis (AD) are among the most common chronic allergic skin disorders. These can be provoked by various food and aeroallergens. Skin prick tests (SPTs) represent the cheapest and most effective method to diagnose type I hypersensitivity. Positive skin tests with a history suggestive of clinical sensitivity strongly incriminate the allergen as a contributor to the disease process. Aims and Objectives: To determine the incidence of positive SPT in patients with chronic allergic skin disorders and to identify the various allergens implicated in positive SPT. Methods: Fifty patients of chronic allergic disorders were recruited in this study. They were evaluated by SPT with both food and aeroallergens. Results: In our study, SPT positivity in patients of CIU was 63.41% and in AD was 77.78%. Out of the 41 patients of CIU, the most common allergen groups showing SPT positivity were dust and pollen, each comprising 26.83% patients. SPT reaction was positive with food items (21.6%), insects (17.07%), fungus (12.20%), and Dermatophagoides farinae, that is, house dust mite (HDM) (7.32%). The allergen which showed maximum positivity was grain dust wheat (19.51%). Among nine patients of AD, maximum SPT positivity was seen with Dermatophagoides farinae, pollen Amaranthus spinosus, grain dust wheat, and cotton mill dust; each comprising 22.22% of patients. Conclusion: Our study showed that a significant number of patients of CIU and AD showed sensitivity to dust, pollen, insects, Dermatophagoides farinae, and fungi on SPT. Thus, it is an important tool in the diagnosis of CIU and AD. PMID:25814704

  15. COAL SLAGGING AND REACTIVITY TESTING

    SciTech Connect

    Donald P. McCollor; Kurt E. Eylands; Jason D. Laumb

    2003-10-01

    carbon as well as slagging. A second phase of the project involved advanced analysis of the baseline coal along with an Australian coal fired at the plant. These analysis results were used in equilibrium thermodynamic modeling along with a coal quality model developed by the EERC to assess slagging, fouling, and opacity for the coals. Bench-scale carbon conversion testing was performed in a drop-tube furnace to assess the reactivity of the coals. The Australian coal had a higher mineral content with significantly more clay minerals present than the baseline coal. The presence of these clay minerals, which tend to melt at relatively low temperatures, indicated a higher potential for problematic slagging than the baseline coal. However, the pyritic minerals, comprising over 25% of the baseline mineral content, may form sticky iron sulfides, leading to severe slagging in the burner region if local areas with reducing conditions exist. Modeling results indicated that neither would present significant fouling problems. The Australian coal was expected to show slagging behavior much more severe than the baseline coal except at very high furnace temperatures. However, the baseline coal was predicted to exhibit opacity problems, as well as have a higher potential for problematic calcium sulfate-based low-temperature fouling. The baseline coal had a somewhat higher reactivity than the Australian coal, which was consistent with both the lower average activation energy for the baseline coal and the greater carbon conversion at a given temperature and residence time. The activation energy of the baseline coal showed some effect of oxygen on the activation energy, with E{sub a} increasing at the lower oxygen concentration, but may be due to the scatter in the baseline coal kinetic values at the higher oxygen level tested.

  16. Test battery with the human cell line activation test, direct peptide reactivity assay and DEREK based on a 139 chemical data set for predicting skin sensitizing potential and potency of chemicals.

    PubMed

    Takenouchi, Osamu; Fukui, Shiho; Okamoto, Kenji; Kurotani, Satoru; Imai, Noriyasu; Fujishiro, Miyuki; Kyotani, Daiki; Kato, Yoshinao; Kasahara, Toshihiko; Fujita, Masaharu; Toyoda, Akemi; Sekiya, Daisuke; Watanabe, Shinichi; Seto, Hirokazu; Hirota, Morihiko; Ashikaga, Takao; Miyazawa, Masaaki

    2015-11-01

    To develop a testing strategy incorporating the human cell line activation test (h-CLAT), direct peptide reactivity assay (DPRA) and DEREK, we created an expanded data set of 139 chemicals (102 sensitizers and 37 non-sensitizers) by combining the existing data set of 101 chemicals through the collaborative projects of Japan Cosmetic Industry Association. Of the additional 38 chemicals, 15 chemicals with relatively low water solubility (log Kow > 3.5) were selected to clarify the limitation of testing strategies regarding the lipophilic chemicals. Predictivities of the h-CLAT, DPRA and DEREK, and the combinations thereof were evaluated by comparison to results of the local lymph node assay. When evaluating 139 chemicals using combinations of three methods based on integrated testing strategy (ITS) concept (ITS-based test battery) and a sequential testing strategy (STS) weighing the predictive performance of the h-CLAT and DPRA, overall similar predictivities were found as before on the 101 chemical data set. An analysis of false negative chemicals suggested a major limitation of our strategies was the testing of low water-soluble chemicals. When excluded the negative results for chemicals with log Kow > 3.5, the sensitivity and accuracy of ITS improved to 97% (91 of 94 chemicals) and 89% (114 of 128). Likewise, the sensitivity and accuracy of STS to 98% (92 of 94) and 85% (111 of 129). Moreover, the ITS and STS also showed good correlation with local lymph node assay on three potency classifications, yielding accuracies of 74% (ITS) and 73% (STS). Thus, the inclusion of log Kow in analysis could give both strategies a higher predictive performance. PMID:25820183

  17. Prereactivation propranolol fails to reduce skin conductance reactivity to prepared fear-conditioned stimuli.

    PubMed

    Spring, Justin D; Wood, Nellie E; Mueller-Pfeiffer, Christoph; Milad, Mohammed R; Pitman, Roger K; Orr, Scott P

    2015-03-01

    Pharmacologic blockade of memory reconsolidation has been demonstrated in fear-conditioned rodents and humans and may provide a means to reduce fearfulness in anxiety disorders and posttraumatic stress disorder. Studying the efficacy of potential interventions in clinical populations is challenging, creating a need for paradigms within which candidate reconsolidation-blocking interventions can be readily tested. We used videos of biologically prepared conditioned stimuli (tarantulas) to test the efficacy of propranolol in blocking reconsolidation of conditioned fear in healthy young adults. Strong differential conditioning, measured by skin conductance, was observed among a screened subset of participants during acquisition. However, subsequent propranolol failed to reduce reactivity to the reactivated conditioned stimulus. These results are consistent with other recent findings and point to a need for testing other candidate drugs. PMID:25224026

  18. Long-term periodic anthelmintic treatments are associated with increased allergen skin reactivity

    PubMed Central

    Endara, P; Vaca, M; Chico, M E; Erazo, S; Oviedo, G; Quinzo, I; Rodriguez, A; Lovato, R; Moncayo, A-L; Barreto, M L; Rodrigues, L C; Cooper, P J

    2010-01-01

    Background The low prevalence of allergic disease in the rural tropics has been attributed to the protective effects of chronic helminth infections. There is concern that treatment-based control programmes for these parasites may lead to an increase in the prevalence of allergic diseases. Objective We measured the impact of 15–17 years of anthelmintic treatment with ivermectin on the prevalence of allergen skin test reactivity and allergic symptoms in school-age children. Methods The prevalence of allergen skin test reactivity, exercise-induced bronchospasm and allergic symptoms was compared between school-age children living in communities that had received community-based treatments with ivermectin (for onchocerciasis control) for a period of 15–17 years with those living in geographically adjacent communities that had received no ivermectin. Results The prevalence of allergen skin test reactivity was double in children living in treated communities compared with those in untreated communities (16.7% vs. 8.7%, adjusted OR 2.10, 95% CI 1.50–2.94, P<0.0001), and the effect was mediated partly by a reduced prevalence of Trichuris trichiura among treated children. Ivermectin treatments were associated with an increased prevalence of recent eczema symptoms (adjusted OR 2.24, 95% CI 1.05–4.78, P=0.04) but not symptoms of asthma or rhino-conjunctivitis. The effect on eczema symptoms was not associated with reductions in geohelminth infections. Conclusion Long-term periodic treatments with ivermectin were associated with an increased prevalence of allergen skin test reactivity. There was some evidence that treatment was associated with an increased prevalence of recent eczema symptoms but not those of asthma or rhino-conjunctivitis. Cite this as: P. Endara, M. Vaca, M. E. Chico, S. Erazo, G. Oviedo, I. Quinzo, A. Rodriguez R. Lovato, A.-L. Moncayo, M. L. Barreto, L. C. Rodrigues and P. J. Cooper, Clinical & Experimental Allergy, 2010 (40) 1669–1677. PMID

  19. Montenegro skin test and age of skin lesion as predictors of treatment failure in cutaneous leishmaniasis.

    PubMed

    Antonio, Liliane de Fátima; Fagundes, Aline; Oliveira, Raquel Vasconcellos Carvalhaes; Pinto, Priscila Garcia; Bedoya-Pacheco, Sandro Javier; Vasconcellos, Erica de Camargo Ferreira e; Valete-Rosalino, Maria Cláudia; Lyra, Marcelo Rosandiski; Passos, Sônia Regina Lambert; Pimentel, Maria Inês Fernandes; Schubach, Armando de Oliveira

    2014-01-01

    A case-control study was conducted to examine the association among the Montenegro skin test (MST), age of skin lesion and therapeutic response in patients with cutaneous leishmaniasis (CL) treated at Evandro Chagas National Institute of Infectious Diseases (INI), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil. For each treatment failure (case), two controls showing skin lesion healing following treatment, paired by sex and age, were randomly selected. All patients were treated with 5 mg Sb(5+)/kg/day of intramuscular meglumine antimoniate (Sb(5+)) for 30 successive days. Patients with CL were approximately five times more likely to fail when lesions were less than two months old at the first appointment. Patients with treatment failure showed less intense MST reactions than patients progressing to clinical cure. For each 10 mm of increase in MST response, there was a 26% reduction in the chance of treatment failure. An early treatment - defined as a treatment applied for skin lesions, which starts when they are less than two months old at the first appointment -, as well as a poor cellular immune response, reflected by lower reactivity in MST, were associated with treatment failure in cutaneous leishmaniasis. PMID:25229216

  20. MONTENEGRO SKIN TEST AND AGE OF SKIN LESION AS PREDICTORS OF TREATMENT FAILURE IN CUTANEOUS LEISHMANIASIS

    PubMed Central

    Antonio, Liliane de Fátima; Fagundes, Aline; Oliveira, Raquel Vasconcellos Carvalhaes; Pinto, Priscila Garcia; Bedoya-Pacheco, Sandro Javier; Vasconcellos, Érica de Camargo Ferreira e; Valete-Rosalino, Maria Cláudia; Lyra, Marcelo Rosandiski; Passos, Sônia Regina Lambert; Pimentel, Maria Inês Fernandes; Schubach, Armando de Oliveira

    2014-01-01

    A case-control study was conducted to examine the association among the Montenegro skin test (MST), age of skin lesion and therapeutic response in patients with cutaneous leishmaniasis (CL) treated at Evandro Chagas National Institute of Infectious Diseases (INI), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil. For each treatment failure (case), two controls showing skin lesion healing following treatment, paired by sex and age, were randomly selected. All patients were treated with 5 mg Sb5+/kg/day of intramuscular meglumine antimoniate (Sb5+) for 30 successive days. Patients with CL were approximately five times more likely to fail when lesions were less than two months old at the first appointment. Patients with treatment failure showed less intense MST reactions than patients progressing to clinical cure. For each 10 mm of increase in MST response, there was a 26% reduction in the chance of treatment failure. An early treatment - defined as a treatment applied for skin lesions, which starts when they are less than two months old at the first appointment -, as well as a poor cellular immune response, reflected by lower reactivity in MST, were associated with treatment failure in cutaneous leishmaniasis. PMID:25229216

  1. A diagnostic skin test for Onchocerca volvulus infection.

    PubMed

    Ngu, J L; Ndumbe, P M; Titanji, V; Leke, R

    1981-09-01

    Onchocerca supernatant (OS) was prepared by a technique permitting live microfilariae to migrate from nodule tissue through agar gel into sterile Hanks balanced salt/Penicillin-Streptomycin solution where they metabolized. The OS, after dialysis, was passed through Seitz viral filter and either concentrated or lyophilized. Using rabbit antiserum in immunodiffusion and immunoelectrophoresis tests, microfilariae proteins and also human protein were detected in out OS. No common antigens were found between this and somatic extracts of Loa loa, O. gutturosa, O. volvulus, L. carinii, D. immittis and A. lumbricoides. 125I labelled OS was purified by passage through protein A column and then through immunosorbent column of horse anti-human serum linked to CNB-activated sepharose 4B. Autoradiography, after sodium dodecyl sulphate polyacylamide slab gel eletrophoresis of purified OS, showed 10 protein bands in the molecular range 10,000 to 125,000. Skin prick tests with OS, shown not to be contaminated with Hepatitis B antigens, elicited immediate hypersensitivity reaction. Using our criteria, positive reactions were seen in 81% of proven onchocerca cases and only occasionally in Loasis 4.5%, ascaridiasis 13.5% or healthy controls 2.4%. The poor skin reactivity to OS in loasis was not due to immunosuppression as these patients, when also infested with ascaris, reacted just as well as onchocerca patients with ascaris to skin prick test using somatic extracts of ascaris. PMID:6808726

  2. Quiz: Test Your Skin Cancer IQ

    MedlinePlus

    ... of skin is usually the first step in skin cancer treatment and may have already occurred in the process ... Skin Cancer" Articles Skin Cancer Can Strike Anyone / Skin Cancer: Biology, Risk Factors & Treatment / Timely Healthcare Checkup Catches Melanoma Early / NIH Research ...

  3. The skin prick test - European standards.

    PubMed

    Heinzerling, Lucie; Mari, Adriano; Bergmann, Karl-Christian; Bresciani, Megon; Burbach, Guido; Darsow, Ulf; Durham, Stephen; Fokkens, Wytske; Gjomarkaj, Mark; Haahtela, Tari; Bom, Ana Todo; Wöhrl, Stefan; Maibach, Howard; Lockey, Richard

    2013-01-01

    Skin prick testing is an essential test procedure to confirm sensitization in IgE-mediated allergic disease in subjects with rhinoconjunctivitis, asthma, urticaria, anapylaxis, atopic eczema and food and drug allergy. This manuscript reviews the available evidence including Medline and Embase searches, abstracts of international allergy meetings and position papers from the world allergy literature. The recommended method of prick testing includes the appropriate use of specific allergen extracts, positive and negative controls, interpretation of the tests after 15 - 20 minutes of application, with a positive result defined as a wheal ≥3 mm diameter. A standard prick test panel for Europe for inhalants is proposed and includes hazel (Corylus avellana), alder (Alnus incana), birch (Betula alba), plane (Platanus vulgaris), cypress (Cupressus sempervirens), grass mix (Poa pratensis, Dactilis glomerata, Lolium perenne, Phleum pratense, Festuca pratensis, Helictotrichon pretense), Olive (Olea europaea), mugwort (Artemisia vulgaris), ragweed (Ambrosia artemisiifolia), Alternaria alternata (tenuis), Cladosporium herbarum, Aspergillus fumigatus, Parietaria, cat, dog, Dermatophagoides pteronyssinus, Dermatophagoides farinae, and cockroach (Blatella germanica). Standardization of the skin test procedures and standard panels for different geographic locations are encouraged worldwide to permit better comparisons for diagnostic, clinical and research purposes. PMID:23369181

  4. Use of thermography in testing skin creams

    NASA Astrophysics Data System (ADS)

    Anttonen, Hannu; Kauppinen, Timo T.; Lehmuskallio, Eero; Rintamaki, Hannu

    1994-03-01

    The aim of the study was to test the effect of skin creams and their components in windy (3 m/s) and cold (-15 degree(s)C) conditions on face temperature and heat flux. The tests were carried out in a climatic chamber with 18 persons sitting in front of the opening of the wind tunnel, the wind directed against the face. Skin temperatures were measured from 4 points on both sides of the face with thermistors and the heat fluxes were measured using heat flux sensors on both cheeks. Also the ambient temperature and wind were registered. In addition to these measurements an IR thermal scanner was also used to measure the spatial and temporal distribution of temperature variation on the face during the exposure. The results were continuously recorded on VHS-video tape. Using still pictures from recorded material the area temperature of the cheek was measured, which described the mean temperature of the cheek. Test periods were 30 minutes and the same test subjects were not used until 48 h after the previous cold exposure. The test persons were young (20 - 30 years) healthy male persons. The total number of tests was 38.

  5. The skin prick test – European standards

    PubMed Central

    2013-01-01

    Skin prick testing is an essential test procedure to confirm sensitization in IgE-mediated allergic disease in subjects with rhinoconjunctivitis, asthma, urticaria, anapylaxis, atopic eczema and food and drug allergy. This manuscript reviews the available evidence including Medline and Embase searches, abstracts of international allergy meetings and position papers from the world allergy literature. The recommended method of prick testing includes the appropriate use of specific allergen extracts, positive and negative controls, interpretation of the tests after 15 – 20 minutes of application, with a positive result defined as a wheal ≥3 mm diameter. A standard prick test panel for Europe for inhalants is proposed and includes hazel (Corylus avellana), alder (Alnus incana), birch (Betula alba), plane (Platanus vulgaris), cypress (Cupressus sempervirens), grass mix (Poa pratensis, Dactilis glomerata, Lolium perenne, Phleum pratense, Festuca pratensis, Helictotrichon pretense), Olive (Olea europaea), mugwort (Artemisia vulgaris), ragweed (Ambrosia artemisiifolia), Alternaria alternata (tenuis), Cladosporium herbarum, Aspergillus fumigatus, Parietaria, cat, dog, Dermatophagoides pteronyssinus, Dermatophagoides farinae, and cockroach (Blatella germanica). Standardization of the skin test procedures and standard panels for different geographic locations are encouraged worldwide to permit better comparisons for diagnostic, clinical and research purposes. PMID:23369181

  6. Delayed extinction fails to reduce skin conductance reactivity to fear-conditioned stimuli.

    PubMed

    Fricchione, Jon; Greenberg, Mark S; Spring, Justin; Wood, Nellie; Mueller-Pfeiffer, Christoph; Milad, Mohammed R; Pitman, Roger K; Orr, Scott P

    2016-09-01

    A brief 10-min time delay between an initial and subsequent exposure to extinction trials has been found to impair memory reconsolidation in fear-conditioned rodents and humans, providing a potential means to reduce fearfulness in anxiety disorders and posttraumatic stress disorder (PTSD). The present study used videos of biologically prepared, conditioned stimuli (tarantulas) to test the efficacy of delayed extinction in blocking reconsolidation of conditioned fear in healthy young adults. Strong differential conditioning, measured by skin conductance, was observed among a screened subset of participants during acquisition. However, the delayed-extinction intervention failed to reduce reactivity to the conditioned stimulus paired with the extinction delay. These results are partially consistent with other recent, mixed findings and point to a need for testing other candidate interventions designed to interfere with the reconsolidation process. PMID:27314560

  7. Test Pile Reactivity Loss Due to Trichloroethylene

    SciTech Connect

    Plumlee, K.E.

    2001-03-09

    The presence of trichloroethylene in the test pile caused a continual decrease in pile reactivity. A system which removed, purified, and returned 12,000 cfh helium to the pile has held contamination to a negligible level and has permitted normal pile operation.

  8. Mental Reactivation and Pleasantness Judgment of Experience Related to Vision, Hearing, Skin Sensations, Taste and Olfaction

    PubMed Central

    2016-01-01

    Language acquisition is based on our knowledge about the world and forms through multiple sensory-motor interactions with the environment. We link the properties of individual experience formed at different stages of ontogeny with the phased development of sensory modalities and with the acquisition of words describing the appropriate forms of sensitivity. To test whether early-formed experience related to skin sensations, olfaction and taste differs from later-formed experience related to vision and hearing, we asked Russian-speaking participants to categorize or to assess the pleasantness of experience mentally reactivated by sense-related adjectives found in common dictionaries. It was found that categorizing adjectives in relation to vision, hearing and skin sensations took longer than categorizing adjectives in relation to olfaction and taste. In addition, experience described by adjectives predominantly related to vision, hearing and skin sensations took more time for the pleasantness judgment and generated less intense emotions than that described by adjectives predominantly related to olfaction and taste. Interestingly the dynamics of skin resistance corresponded to the intensity and pleasantness of reported emotions. We also found that sense-related experience described by early-acquired adjectives took less time for the pleasantness judgment and generated more intense and more positive emotions than that described by later-acquired adjectives. Correlations were found between the time of the pleasantness judgment of experience, intensity and pleasantness of reported emotions, age of acquisition, frequency, imageability and length of sense-related adjectives. All in all these findings support the hypothesis that early-formed experience is less differentiated than later-formed experience. PMID:27400090

  9. Purification, partial characterization, and identification of a skin-reactive protein antigen of Mycobacterium bovis BCG.

    PubMed

    De Bruyn, J; Bosmans, R; Turneer, M; Weckx, M; Nyabenda, J; Van Vooren, J P; Falmagne, P; Wiker, H G; Harboe, M

    1987-01-01

    An immunogenic and skin-reactive protein called P64 was purified from Sauton zinc-deficient culture filtrate of Mycobacterium bovis BCG by using successively hydrophobic chromatography on phenyl-Sepharose, ion exchange on DEAE-Sephacel, and molecular sieving on Sephadex G-200. The final P64 preparation was found to be homogeneous based on several analyses. Protein P64 was a constituent of BCG cells since it was present in soluble cellular extract from normally grown BCG cells. It represented 8 to 9% of the soluble proteins of the extract and appeared as the major soluble protein antigen of BCG. This protein was found to have a molecular weight of 64,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, but in molecular sieving it eluted at a volume corresponding to a molecular weight of 246,000. An abnormal UV spectrum was observed for this protein. Its amino acid composition showed an abundance of acidic amino acids (or their amides). Aromatic amino acids represented only 3% of the total amino acid residues. The NH2-terminal amino acid sequence of this protein (10 amino acids) was determined. Its sugar content measured with the phenol-sulfuric acid test was lower than 0.3% (wt/wt.) Isolated P64 was tested by various crossed-immunoelectrophoresis techniques and was shown to correspond to antigen 82 in the reference system for BCG antigens. The protein antigen P64 elicited a delayed cutaneous reaction in guinea pigs sensitized with either living or heat-killed BCG. Its potency in skin reaction was, respectively, two- and threefold that of the BCG purified protein derivative. The two types of sensitization used for skin test reactions promoted significant immunoglobulin G antibody production against the protein antigen P64 in guinea pigs 7 weeks after sensitization. PMID:3539805

  10. A fluorescence high throughput screening method for the detection of reactive electrophiles as potential skin sensitizers.

    PubMed

    Avonto, Cristina; Chittiboyina, Amar G; Rua, Diego; Khan, Ikhlas A

    2015-12-01

    Skin sensitization is an important toxicological end-point in the risk assessment of chemical allergens. Because of the complexity of the biological mechanisms associated with skin sensitization, integrated approaches combining different chemical, biological and in silico methods are recommended to replace conventional animal tests. Chemical methods are intended to characterize the potential of a sensitizer to induce earlier molecular initiating events. The presence of an electrophilic mechanistic domain is considered one of the essential chemical features to covalently bind to the biological target and induce further haptenation processes. Current in chemico assays rely on the quantification of unreacted model nucleophiles after incubation with the candidate sensitizer. In the current study, a new fluorescence-based method, 'HTS-DCYA assay', is proposed. The assay aims at the identification of reactive electrophiles based on their chemical reactivity toward a model fluorescent thiol. The reaction workflow enabled the development of a High Throughput Screening (HTS) method to directly quantify the reaction adducts. The reaction conditions have been optimized to minimize solubility issues, oxidative side reactions and increase the throughput of the assay while minimizing the reaction time, which are common issues with existing methods. Thirty-six chemicals previously classified with LLNA, DPRA or KeratinoSens™ were tested as a proof of concept. Preliminary results gave an estimated 82% accuracy, 78% sensitivity, 90% specificity, comparable to other in chemico methods such as Cys-DPRA. In addition to validated chemicals, six natural products were analyzed and a prediction of their sensitization potential is presented for the first time. PMID:26455772

  11. Reactive skin decontamination lotion (RSDL) for the decontamination of chemical warfare agent (CWA) dermal exposure.

    PubMed

    Schwartz, M D; Hurst, C G; Kirk, M A; Reedy, S J D; Braue, E H

    2012-08-01

    Rapid decontamination of the skin is the single most important action to prevent dermal absorption of chemical contaminants in persons exposed to chemical warfare agents (CWA) and toxic industrial chemicals (TICs) as a result of accidental or intentional release. Chemicals on the skin may be removed by mechanical means through the use of dry sorbents or water. Recent interest in decontamination systems which both partition contaminants away from the skin and actively neutralize the chemical has led to the development of several reactive decontamination solutions. This article will review the recently FDA-approved Reactive Skin Decontamination Lotion (RSDL) and will summarize the toxicity and efficacy studies conducted to date. Evidence of RSDL's superior performance against vesicant and organophosphorus chemical warfare agents compared to water, bleach, and dry sorbents, suggests that RSDL may have a role in mass human exposure chemical decontamination in both the military and civilian arenas. PMID:22352732

  12. Anaphylaxis to muscle relaxants: rational for skin tests.

    PubMed

    Moneret-Vautrin, D A; Kanny, G

    2002-09-01

    IgE-dependent allergy to muscle relaxants (MR) has an estimated prevalence of 1 out of 6500 General Anesthesias (GA). 62% of anaphylaxis during surgery are due to MR anaphylaxis. All the molecules are divalent, carrying two NH4+ epitopes (quaternary ammonium ions), either structurally or after rapid in vivo protonization (vecuronium). The excellent overall performance of skin test makes them the golden standard for the diagnosis of anaphylactoid reactions. Techniques include intradermal tests and prick-tests. The current localizations are the forearm and the back. Positivity criteria are 3 mm for prick-tests. For IDTs, the criterium is the doubling of the size of the injection papula, when 0.02 to 0.04 ml is injected: 8 mm. The recommended concentrations are not falsely negative. Commercial concentrations can be tested by prick tests, except for mivacurium and atracurium tested of 1:10 dilution. A scale of concentrations is advised for IDT starting with 1:10,000, up to a normally non reactive concentration that is: 100 micrograms/ml (succinylcholine), 200 micrograms/ml (gallamine), 10 micrograms/ml (atracurium), 2 micrograms/ml (mivacurium), 200 micrograms/ml (pancuronium), 400 micrograms/ml (vecuronium), 1,000 micrograms/ml (rocuronium), 200 micrograms/ml (cis atracurium). The specificity and sensitivity of the skin tests to MRs are greater than 95%. The reproducibility over years is 88%. The overall concordance of PT and IDR is 97%. Both types of tests can be used for the diagnosis. IDT have to be carried out for the search of the cross sensitization. 84% of patients do have cross sensitization to MRs but only 16% react to all MRs. The further use of MRs selected by negative IDTs has been proved to be safe. PMID:12389445

  13. Functional cloning of a gp100-reactive T-cell receptor from vitiligo patient skin.

    PubMed

    Klarquist, Jared; Eby, Jonathan M; Henning, Steven W; Li, Mingli; Wainwright, Derek A; Westerhof, Wiete; Luiten, Rosalie M; Nishimura, Michael I; Le Poole, I Caroline

    2016-05-01

    We isolated gp100-reactive T cells from perilesional skin of a patient with progressive vitiligo with superior reactivity toward melanoma cells compared with tumor-infiltrating lymphocytes 1520, a melanoma-derived T-cell line reactive with the same cognate peptide. After dimer enrichment and limited dilution cloning, amplified cells were subjected to reverse transcription and 5' RACE to identify the variable TCRα and TCRβ subunit sequences. The full-length sequence was cloned into a retroviral vector separating both subunits by a P2A slippage sequence and introduced into Jurkat cells and primary T cells. Cytokine secreted by transduced cells in response to cognate peptide and gp100-expressing targets signifies that we have successfully cloned a gp100-reactive T-cell receptor from actively depigmenting skin. PMID:26824221

  14. [Precision and economy of skin prick tests].

    PubMed

    Kupczyk, Maciej; Kupryś, Izabela; Kuna, Piotr

    2002-03-01

    Due to a rise in the number of cases of allergic disease and a need to increase financial resources for the diagnosis of these conditions, the possibility of reducing costs of skin pricks tests (SPT) was very welcome. In an attempt to reduce costs some practitioners use one lancet for several pricks in one patient. The purpose of this study was to determine whether this way of performing SPT influences the results. 52 subjects with (39) and without (13) atopy were tested with histamine, codeine and standard allergen extracts. SPT were applied to the volar surface of a randomly assigned forearm using two methods: one lancet-one prick on one forearm (single test method) and one lancet-multiple pricks ("multiple test" method) on the other. The false positive tests at the placebo site following allergen were recorded only in multiple test method, in 41 out of 72 pricks (p < 0.00001) when all reactions above baseline were considered and in 26 out of 72 (p = 0.00001) when a 3 mm cut-off was considered. The size of the false positive reaction depends on the intensity of the reaction to the preceding allergen (rang Spearman factor R = 0.706, p < 0.000001) and decreases in the second consecutive placebo test. Our data show that one lancet for multiple test method cannot be used to diagnose factors responsible for allergy, particularly in patients qualified for immunotherapy and in scientific studies. For financial reasons multiple test method can be used in screening and epidemiological studies where atopy is studied and there is no need to identify the specific allergen. PMID:12053585

  15. Expanded Small-Scale Shock Reactivity Test

    NASA Astrophysics Data System (ADS)

    Granholm, Richard

    2005-07-01

    Explosives react from a strong shock, even in quantities too small for detonation. The potential for a new material to be an explosive can be evaluated from this shock reactivity. The recently developed small-scale shock reactivity test (SSRT)ootnotetextH. W. Sandusky, R. H. Granholm, D. G. Bohl, ``Small-Scale Shock Reactivity Test,'' NSWC Technical Report (in publication), Naval Surface Warfare Center, Indian Head, MD 20640 uses very high confinement to allow prompt reactions to occur in less than half-gram samples well below critical diameter, with the reactions quantified by a dent in a soft aluminum witness block. This test has been expanded to simultaneously measure both early and late-time reactions from a single sample subjected to the output from an RP-80 detonator. The sample apparatus is further confined within a small chamber instrumented with a pressure gage for internal air blast. This provides a measure of late-time reactions, such as from fuel/air combustion. Results are shown from several simultaneous early- and late-reaction measurements.

  16. [Introduce a new vitro replacement method of skin irritation test].

    PubMed

    Sun, Likui; Hou, Li; Shi, Yanping

    2011-09-01

    A series of new replacement methods of skin irritation test such as EpiSkin, EpiDermSIT (updated) and SkinEthicRHE have been validated by ECVAM. Due to it, animals are protected to the full extent. These provide more methods for biological evaluation of medical devices. PMID:22242390

  17. In vitro and human testing strategies for skin irritation.

    PubMed

    Robinson, M K; Osborne, R; Perkins, M A

    2000-01-01

    Prior to the manufacture, transport, and marketing of chemicals or products, it is critical to assess their potential for skin toxicity (corrosion or irritation), thereby protecting the worker and consumer from adverse skin effects due to intended or accidental skin exposure. Traditionally, animal testing procedures have provided the data needed to assess the more severe forms of skin toxicity, and current regulations may require animal test data before permission can be obtained to manufacture, transport, or market chemicals or the products that contain them. In recent years, the use of animals to assess skin safety has been opposed by some as inhumane and unnecessary. The conflicting needs of the industrial toxicologist to (1) protect human safety, (2) comply with regulations, and (3) reduce animal testing have led to major efforts to develop alternative, yet predictive, test methods. A variety of in vitro skin corrosion test methods have been developed and several have successfully passed initial international validation. These have included skin or epidermal equivalent assays that have been shown to distinguish corrosive from noncorrosive chemicals. These skin/epidermal equivalent assays have also been modified and used to assess skin irritation potential relative to existing human exposure test data. The data show a good correlation between in vitro assay data and different types of human skin irritation data for both chemicals and consumer products. The effort to eliminate animal tests has also led to the development of a novel human patch test for assessment of acute skin irritation potential. A case study shows the benefits of in vitro and human skin irritation tests compared to the animal tests they seek to replace, and strategies now exist to adequately assess human skin irritation potential without the need to rely on animal test methods. PMID:11083109

  18. Harsh Parenting and Child Externalizing Behavior: Skin Conductance Level Reactivity as a Moderator

    ERIC Educational Resources Information Center

    Erath, Stephen A.; El-Sheikh, Mona; Cummings, E. Mark

    2009-01-01

    Skin conductance level reactivity (SCLR) was examined as a moderator of the association between harsh parenting and child externalizing behavior. Participants were 251 boys and girls (8-9 years). Mothers and fathers provided reports of harsh parenting and their children's externalizing behavior; children also provided reports of harsh parenting.…

  19. Skin Conductance Level Reactivity Moderates the Association between Harsh Parenting and Growth in Child Externalizing Behavior

    ERIC Educational Resources Information Center

    Erath, Stephen A.; El-Sheikh, Mona; Hinnant, J. Benjamin; Cummings, E. Mark

    2011-01-01

    Skin conductance level reactivity (SCLR) was examined as a moderator of the association between harsh parenting at age 8 years and growth in child externalizing behavior from age 8 to age 10 (N = 251). Mothers and fathers provided reports of harsh parenting and their children's externalizing behavior; children also provided reports of harsh…

  20. Children's Skin Conductance Reactivity as a Mechanism of Risk in the Context of Parental Depressive Symptoms

    ERIC Educational Resources Information Center

    Cummings, E. Mark; El-Sheikh, Mona; Kouros, Chrystyna D.; Keller, Peggy S.

    2007-01-01

    Background: Children's physiological reactivity was examined as a moderator of relations between parental dysphoria and child adjustment problems, addressing gaps in the study of child characteristics as risk processes. Method: One hundred fifty-seven children (86 boys, 71 girls) were assessed twice over a two-year interval. Skin conductance level…

  1. Skin testing and incremental challenge in the evaluation of adverse reactions to local anesthetics.

    PubMed

    Schatz, M

    1984-10-01

    True allergic reactions to local anesthetics (LAs) probably make up no more than 1% of all adverse LA reactions. A diagnosis of true potential allergic reactivity is made difficult because (1) the history of the prior reaction may be vague or equivocal and (2) the lack of identification of the actual specific LA hapten-carrier complex limits the potential usefulness of immunologic tests. Nonetheless, since avoidance of LAs may be associated with substantial increased pain or increased risk and because true allergic reactions are rare, investigators and clinicians have used skin testing, incremental challenge, or both as a means of identifying a safe LA for a patient with a history of a prior adverse reaction. Review of the literature dealing with LA skin testing and incremental challenge suggests the following: (1) Skin testing with LAs may correlate with a history of an adverse reaction but may produce systemic adverse reactions, especially with undiluted drug. (2) Although false positive skin tests have been reported, most skin-tested patients who subsequently tolerate an LA have a negative skin test to that drug, and false negative skin tests have not been clearly documented. (3) Incremental challenge beginning with diluted LA is a safe and effective means of identifying a drug that a patient with a history of a prior adverse reaction can tolerate. (4) Current concepts of non-cross-reacting LA groups may be useful in the choice of a drug for use in skin testing and incremental challenge. (5) Preservatives in LAs may account for some but probably not the majority of adverse reactions to LAs. On the basis of this literature review, a practical protocol including dilutional skin testing and incremental challenge is presented for use in evaluating patients with prior adverse reactions to LAs. PMID:6491108

  2. Point skin tests in allergology: estimation of point skin tests with histamine solutions of different concentration

    NASA Astrophysics Data System (ADS)

    Zuber, Janusz; Kruszewski, Jerzy; Klosowicz, Stanislaw J.; Zmija, Jozef

    1995-08-01

    The application of liquid crystal contact thermography for point skin tests used in allergology diagnostic has been studied. The effect of a concentration of histamine, adopted as the etalon substance, on observed temperature fields is presented. Obtained results have been confirmed by thermovision measurements. A correlation between studied method and visual estimation used until now is the best for temperature range observed as a blue color.

  3. UVB dependence of quantum dot reactive oxygen species generation in common skin cell models

    PubMed Central

    MORTENSEN, LUKE J.; FAULKNOR, RENEA; RAVICHANDRAN, SUPRIYA; ZHENG, HONG; DELOUISE, LISA A.

    2015-01-01

    Studies have shown that UVB can slightly increase the penetration of nanoparticles through skin and significantly alter skin cell biology, thus it is important to understand if and how UVB may impact subsequent nanoparticle skin cell interactions. The research presented herein evaluates the effect of UVB on quantum dot (QD) uptake and reactive oxygen species (ROS) generation in primary keratinocytes, primary melanocytes, and related cell lines. QD exposure induced cell type dependent ROS responses increased by pre-exposing cells to UVB and correlated with the level of QD uptake. Our results suggest that keratinocytes may be at greater risk for QD induced ROS generation than melanocytes, and raise awareness about the differential cellular effects that topically applied nanomaterials may have on UVB exposed skin. PMID:26485933

  4. UVB Dependence of Quantum Dot Reactive Oxygen Species Generation in Common Skin Cell Models.

    PubMed

    Mortensen, Luke J; Faulknor, Renea; Ravichandran, Supriya; Zheng, Hong; DeLouise, Lisa A

    2015-09-01

    Studies have shown that UVB can slightly increase the penetration of nanoparticles through skin and significantly alter skin cell biology, thus it is important to understand if and how UVB may impact subsequent nanoparticle skin cell interactions. The research presented herein evaluates the effect of UVB on quantum dot (QD) uptake and reactive oxygen species (ROS) generation in primary keratinocytes, primary melanocytes, and related cell lines. QD exposure induced cell type dependent ROS responses increased by pre-exposing cells to UVB and correlated with the level of QD uptake. Our results suggest that keratinocytes may be at greater risk for QD induced ROS generation than melanocytes, and raise awareness about the differential cellular effects that topically applied nanomaterials may have on UVB exposed skin. PMID:26485933

  5. Skin testing with food, codeine, and histamine in exercise-induced anaphylaxis.

    PubMed

    Lin, R Y; Barnard, M

    1993-06-01

    A 33-year-old Chinese woman with exercise-induced anaphylaxis after ingesting Chinese seafood noodle soup, was studied for skin test reactivity to food, histamine, and codeine. Prick skin tests were negative for shrimp, wheat, and chicken soup base, but were positive at 5 to 6 mm (wheal diameter) to the whole broth after it had been combined with the other ingredients. No significant (> 3 mm) wheals were observed in eight controls who were simultaneously tested with the broth. To assess the role of exercise, three series of skin tests were performed with histamine, codeine, and whole broth before and after aerobic exercise on two occasions. Codeine elicited consistent increases in wheal size after exercise compared with pre-exercise skin tests. Histamine and whole broth wheal sizes did not increase significantly. Three control subjects also had codeine and histamine skin tests before and after exercise, No exercise-associated increases were noted for codeine. Potential insights into mast cell abnormalities in exercise-induced anaphylaxis may be gained by skin testing patterns with codeine and other mast cell degranulating agents. PMID:8507042

  6. Measurements of UV-generated free radicals/reactive oxygen species (ROS) in skin

    NASA Astrophysics Data System (ADS)

    Herrling, Th.; Jung, K.; Fuchs, J.

    2006-03-01

    Free radicals/reactive oxygen species (ROS) generated in skin by UV irradiation were measured by electron spin resonance (ESR). To increase the sensitivity of measurement the short life free radicals/ROS were scavenged and accumulated by using the nitroxyl probe 3-carboxy-2,2,5,5-tetrametylpyrrolidine-1-oxyl (PCA). The spatial distribution of free radicals/ROS measured in pig skin biopsies with ESR imaging after UV irradiation corresponds to the intensity decay of irradiance in the depth of the skin. The main part of free radicals/ROS were generated by UVA (320-400 nm) so that the spatial distribution of free radicals reaches up to the lower side of the dermis. In vivo measurements on human skin were performed with a L-band ESR spectrometer and a surface coil integrating the signal intensities from all skin layers to get a sufficient signal amplitude. Using this experimental arrangement the protection of UVB and UVA/B filter against the generation of free radicals/ROS in skin were measured. The protection against ROS and the repair of damages caused by them can be realized with active antioxidants characterized by a high antioxidative power (AP). The effect of UV filter and antioxidants corresponding to their protection against free radicals/ROS in skin generated by UVAB irradiation can be quantified by the new radical sun protection factor (RSF). The RSF indicates the increase of time for staying in the sun to generate the same number of free radicals/ROS in the skin like for the unprotected skin. Regarding the amount of generated free radicals/ROS in skin as an biophysical endpoint the RSF characterizes both the protection against UVB and UVA radiation.

  7. Putting the parts together: combining in vitro methods to test for skin sensitizing potentials.

    PubMed

    Bauch, Caroline; Kolle, Susanne N; Ramirez, Tzutzuy; Eltze, Tobias; Fabian, Eric; Mehling, Annette; Teubner, Wera; van Ravenzwaay, Bennard; Landsiedel, Robert

    2012-08-01

    Allergic contact dermatitis is a common skin disease and is elicited by repeated skin contact with an allergen. In the regulatory context, currently only data from animal experiments are acceptable to assess the skin sensitizing potential of substances. Animal welfare and EU Cosmetic Directive/Regulation call for the implementation of animal-free alternatives for safety assessments. The mechanisms that trigger skin sensitization are complex and various steps are involved. Therefore, a single in vitro method may not be able to accurately assess this endpoint. Non-animal methods are being developed and validated and can be used for testing strategies that ensure a reliable prediction of skin sensitization potentials. In this study, the predictivities of four in vitro assays, one in chemico and one in silico method addressing three different steps in the development of skin sensitization were assessed using 54 test substances of known sensitizing potential. The predictivity of single tests and combinations of these assays were compared. These data were used to develop an in vitro testing scheme and prediction model for the detection of skin sensitizers based on protein reactivity, activation of the Keap-1/Nrf2 signaling pathway and dendritic cell activation. PMID:22659254

  8. Development of a forensic skin colour predictive test.

    PubMed

    Maroñas, Olalla; Phillips, Chris; Söchtig, Jens; Gomez-Tato, Antonio; Cruz, Raquel; Alvarez-Dios, José; de Cal, María Casares; Ruiz, Yarimar; Fondevila, Manuel; Carracedo, Ángel; Lareu, María V

    2014-11-01

    There is growing interest in skin colour prediction in the forensic field. However, a lack of consensus approaches for recording skin colour phenotype plus the complicating factors of epistatic effects, environmental influences such as exposure to the sun and unidentified genetic variants, present difficulties for the development of a forensic skin colour predictive test centred on the most strongly associated SNPs. Previous studies have analysed skin colour variation in single unadmixed population groups, including South Asians (Stokowski et al., 2007, Am. J. Hum. Genet, 81: 1119-32) and Europeans (Jacobs et al., 2013, Hum Genet. 132: 147-58). Nevertheless, a major challenge lies in the analysis of skin colour in admixed individuals, where co-ancestry proportions do not necessarily dictate any one person's skin colour. Our study sought to analyse genetic differences between African, European and admixed African-European subjects where direct spectrometric measurements and photographs of skin colour were made in parallel. We identified strong associations to skin colour variation in the subjects studied from a pigmentation SNP discovery panel of 59 markers and developed a forensic online classifier based on naïve Bayes analysis of the SNP profiles made. A skin colour predictive test is described using the ten most strongly associated SNPs in 8 genes linked to skin pigmentation variation. PMID:25082135

  9. Skin Testing for Allergic Rhinitis: A Health Technology Assessment

    PubMed Central

    2016-01-01

    Background Allergic rhinitis is the most common type of allergy worldwide. The accuracy of skin testing for allergic rhinitis is still debated. This health technology assessment had two objectives: to determine the diagnostic accuracy of skin-prick and intradermal testing in patients with suspected allergic rhinitis and to estimate the costs to the Ontario health system of skin testing for allergic rhinitis. Methods We searched All Ovid MEDLINE, Embase, and Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, CRD Health Technology Assessment Database, Cochrane Central Register of Controlled Trials, and NHS Economic Evaluation Database for studies that evaluated the diagnostic accuracy of skin-prick and intradermal testing for allergic rhinitis using nasal provocation as the reference standard. For the clinical evidence review, data extraction and quality assessment were performed using the QUADAS-2 tool. We used the bivariate random-effects model for meta-analysis. For the economic evidence review, we assessed studies using a modified checklist developed by the (United Kingdom) National Institute for Health and Care Excellence. We estimated the annual cost of skin testing for allergic rhinitis in Ontario for 2015 to 2017 using provincial data on testing volumes and costs. Results We meta-analyzed seven studies with a total of 430 patients that assessed the accuracy of skin-prick testing. The pooled pair of sensitivity and specificity for skin-prick testing was 85% and 77%, respectively. We did not perform a meta-analysis for the diagnostic accuracy of intradermal testing due to the small number of studies (n = 4). Of these, two evaluated the accuracy of intradermal testing in confirming negative skin-prick testing results, with sensitivity ranging from 27% to 50% and specificity ranging from 60% to 100%. The other two studies evaluated the accuracy of intradermal testing as a stand-alone tool for diagnosing allergic rhinitis, with

  10. An in vitro human skin test for assessing sensitization potential.

    PubMed

    Ahmed, S S; Wang, X N; Fielding, M; Kerry, A; Dickinson, I; Munuswamy, R; Kimber, I; Dickinson, A M

    2016-05-01

    Sensitization to chemicals resulting in an allergy is an important health issue. The current gold-standard method for identification and characterization of skin-sensitizing chemicals was the mouse local lymph node assay (LLNA). However, for a number of reasons there has been an increasing imperative to develop alternative approaches to hazard identification that do not require the use of animals. Here we describe a human in-vitro skin explant test for identification of sensitization hazards and the assessment of relative skin sensitizing potency. This method measures histological damage in human skin as a readout of the immune response induced by the test material. Using this approach we have measured responses to 44 chemicals including skin sensitizers, pre/pro-haptens, respiratory sensitizers, non-sensitizing chemicals (including skin-irritants) and previously misclassified compounds. Based on comparisons with the LLNA, the skin explant test gave 95% specificity, 95% sensitivity, 95% concordance with a correlation coefficient of 0.9. The same specificity and sensitivity were achieved for comparison of results with published human sensitization data with a correlation coefficient of 0.91. The test also successfully identified nickel sulphate as a human skin sensitizer, which was misclassified as negative in the LLNA. In addition, sensitizers and non-sensitizers identified as positive or negative by the skin explant test have induced high/low T cell proliferation and IFNγ production, respectively. Collectively, the data suggests the human in-vitro skin explant test could provide the basis for a novel approach for characterization of the sensitizing activity as a first step in the risk assessment process. PMID:26251951

  11. High reactive oxygen species in fibrotic and nonfibrotic skin of patients with diffuse cutaneous systemic sclerosis.

    PubMed

    Bourji, Khalil; Meyer, Alain; Chatelus, Emmanuel; Pincemail, Joël; Pigatto, Erika; Defraigne, Jean-Olivier; Singh, François; Charlier, Corinne; Geny, Bernard; Gottenberg, Jacques-Eric; Punzi, Leonardo; Cozzi, Franco; Sibilia, Jean

    2015-10-01

    Systemic sclerosis (SSc) is a chronic multisystemic connective tissue disease characterized by progressive fibrosis affecting skin and internal organs. Despite serious efforts to unveil the pathogenic mechanisms of SSc, they are still unclear. High levels of reactive oxygen species (ROS) in affected patients have been shown, and ROS are suggested to play a role in fibrosis pathogenesis. In this study we evaluate ROS levels in nonfibrotic and fibrotic skin of patients with SSc and we compare them with those obtained from healthy controls. We enrolled nine SSc patients fulfilling the EULAR/ACR classification criteria and seven healthy controls. Patients included four men and five women with mean age of 46 ± 10 years. Controls were matched by sex and age. All patients were affected by the diffuse cutaneous form of SSc and the ANA pattern anti-Scl70. Mean disease duration was 7.5 ± 5 years. Skin involvement was evaluated by modified Rodnan skin score. Skin samples (4-mm punch biopsy) were taken from fibrotic skin and nonfibrotic skin of patients and from healthy controls as well. To detect ROS, specimens were analyzed immediately after sampling by electron paramagnetic resonance spectroscopy. Blood samples were drawn from all patients and controls to assess oxidative stress biomarkers. ROS levels (expressed as median and range, in nmol/L/min/mg of dry weight) were 24.7 (10.9-47.0) in fibrotic skin, 18.7 (7.3-34.0) in nonfibrotic skin, and 7.7 (3.5-13.6) in healthy control skin. ROS levels in fibrotic and nonfibrotic skin of SSc patients were significantly higher than in healthy controls (p = 0.002 and p = 0.009, respectively). ROS levels in fibrotic skin were raised in comparison to nonfibrotic skin, when samples related to each patient were compared (p = 0.01). ROS levels in fibrotic skin were correlated with forced vital capacity (r = -0.75, p = 0.02) and erythrocyte sedimentation rate (r = 0.70, p = 0.04). All other clinical and lab parameters showed no

  12. Ultrasonic testing of reactive powder concrete.

    PubMed

    Washer, Glenn; Fuchs, Paul; Graybeal, Benjamin A; Hartmann, Joseph Lawrence

    2004-02-01

    Concrete is a critical material for the construction of infrastructure facilities throughout the world. Traditional concretes consist of cement paste and aggregates ranging in size from 6 to 25 mm that form a heterogeneous material with substantial compressive strength and a very low tensile strength. Steel reinforcement is used to provide tensile strength for reinforced concrete structures and as a composite the material is useful for structural applications. A new material known as reactive powder concrete (RPC) is becoming available. It differs significantly from traditional concrete; RPC has no large aggregates, and contains small steel fibers that provide additional strength and, in some cases, can replace traditional steel reinforcement. Due to its high density and lack of aggregates, ultrasonic inspections at frequencies 10 to 20 times that of traditional concrete inspections are possible. This paper reports on the initial findings of research conducted to determine the applicability of ultrasonic testing techniques for the condition assessment of RPC. Pulse velocities for shear and longitudinal waves and ultrasonic measurement of the modulus of elasticity for RPC are reported. Ultrasonic crack detection for RPC also is investigated. PMID:15055809

  13. Skin testing for allergic diseases: techniques, indications and interpretations.

    PubMed

    Villacorte, G V

    1978-01-01

    Despite significant strides in serologic methodologies, the skin test, when properly done, has remained the single most sensitive and practical assay for specific dermal-bound reaginic antibody. Its value could further be enhanced if and when characterization and standardization of the allergen extracts become a reality. While the technique is simple, the indications and interpretations of allergy skin tests required the expertise of well-trained allergists. A positive skin reaction is no more than a mere supportive laboratory aid in the diagnosis of allergic disease, which is arrived at through a carefully taken detailed history and a meticulously done physical examination. PMID:748833

  14. Reactivity initiated accident test series Test RIA 1-4

    SciTech Connect

    Martinson, Z.R.; El-Genk, M.S.; Fukuda, S.K.; LaPointe, R.E.; Osetek, D.J.

    1980-05-01

    The Reactivity Initiated Accident (RIA) Test RIA 1-4, the first 9-rod fuel rod bundle RIA Test to be performed at BWR hot startup conditions, was completed on April 16, 1980. The test was performed in the Power Burst Facility (PBF). Objective for Test RIA 1-4 was to provide information regarding loss-of-coolable fuel rod geometry following a RIA event for a peak fuel enthalpy equivalent to the present licensing criteria of 280 cal/g. The most severe RIA is the postulated Boiling Water Reactor (BWR) control rod drop during reactor startup. Therefore the test was conducted at BWR hot startup coolant conditions (538 K, 6.45 MPa, 0.8 1/sec). The test sequence began with steady power operation to condition the fuel, establish a short-lived fission product inventory, and calibrate the calorimetric measurements and core power chambers, neutron flux and gamma flux detectors. The test train was removed from the in-pile tube (IPT) to replace one of the fuel rods with a nominally identical irradiated rod and twelve flux wire monitors. A 2.8 ms period power burst was then performed. Coolant flow measurements were made before and after the power burst to characterize the flow blockage that occurred as a result of fuel rod failure.

  15. Autonomic Nervous System Reactivity During Speech Repetition Tasks: Heart Rate Variability and Skin Conductance.

    PubMed

    Mackersie, Carol L; Calderon-Moultrie, Natalie

    2016-01-01

    Cognitive and emotional challenges may elicit a physiological stress response that can include arousal of the sympathetic nervous system (fight or flight response) and withdrawal of the parasympathetic nervous system (responsible for recovery and rest). This article reviews studies that have used measures of electrodermal activity (skin conductance) and heart rate variability (HRV) to index sympathetic and parasympathetic activity during auditory tasks. In addition, the authors present results from a new study with normal-hearing listeners examining the effects of speaking rate on changes in skin conductance and high-frequency HRV (HF-HRV). Sentence repetition accuracy for normal and fast speaking rates was measured in noise using signal to noise ratios that were adjusted to approximate 80% accuracy (+3 dB fast rate; 0 dB normal rate) while monitoring skin conductance and HF-HRV activity. A significant increase in skin conductance level (reflecting sympathetic nervous system arousal) and a decrease in HF-HRV (reflecting parasympathetic nervous system withdrawal) were observed with an increase in speaking rate indicating sensitivity of both measures to increased task demand. Changes in psychophysiological reactivity with increased auditory task demand may reflect differences in listening effort, but other person-related factors such as motivation and stress may also play a role. Further research is needed to understand how psychophysiological activity during listening tasks is influenced by the acoustic characteristics of stimuli, task demands, and by the characteristics and emotional responses of the individual. PMID:27355761

  16. Endothelial nitric oxide synthase G894T gene polymorphism and response to skin reactive hyperemia.

    PubMed

    Rasool, Aida Hanum Ghulam; Ghazali, Dzuzaini Mohd; Abdullah, Haswati; Halim, Ahmad Sukari; Wong, Abd Rahim

    2009-09-01

    Post occlusive skin reactive hyperemia (PORH) is a tool used to assess microcirculation. Endothelial nitric oxide synthase (eNOS) mediates nitric oxide (NO) production; polymorphism of the eNOS gene may affect response to the PORH process. This study aims to determine whether eNOS G894T gene polymorphism affects response to skin PORH. 230 normotensive male and females between 18 and 40 years participated in this cross-sectional study. 170 subjects were of the homozygous GG genotype, whereas 60 were of the GT genotype. Skin PORH was performed by occlusion of the upper arm at 200 mm Hg for 3 min. Skin perfusion and temperature were monitored before, during and after occlusion release using the laser Doppler fluximetry. There were no significant differences between genotypes in their baseline blood pressure, serum cholesterol, BMI and age. Maximum change in perfusion after occlusion release (PORHmax) for the GG and GT genotypes were not significantly different at 50.15+/-1.29 vs. 47.92+/-2.17 AU; ANCOVA, p=0.351. Peak perfusion (PORHpeak) were also not significantly different between the two genotypes (61.23+/-1.36 vs. 57.72+/-2.32 AU; p=0.169). Minimum baseline perfusion were however higher in the GG compared to the GT genotype (10.83+/-0.29 vs. 9.61+/-0.50, p=0.029). We conclude that microvascular reactivity, assessed by change in perfusion after temporary ischemia was not significantly different between the GG and GT genotypes of the eNOS G894T gene. eNOS 894T allele carriers however, have lower baseline perfusion compared to the homozygous G894 allele carrier. PMID:19481100

  17. Early skin and challenge testing after rocuronium anaphylaxis.

    PubMed

    Schulberg, E M; Webb, A R; Kolawole, H

    2016-05-01

    We present a case of early skin and challenge testing in a patient following severe anaphylaxis to rocuronium. The patient presented for semi-elective laparoscopic cholecystectomy and developed anaphylaxis with severe cardiovascular collapse after induction of anaesthesia. Surgery was cancelled but was considered necessary before the recommended four to six weeks for formal allergy testing. Limited skin and challenge testing was performed to rocuronium and cisatracurium while the patient was in the intensive care unit to identify a safe neuromuscular blocking drug for subsequent early surgery. The subsequent surgery, 48 hours after the initial reaction, was uneventful. The case highlights the difficulties when anaesthetising patients with recent anaphylaxis who have not yet had formal allergy testing and presents a potential management strategy involving early skin testing. PMID:27246945

  18. Evaluation of a High-Throughput Peptide Reactivity Format Assay for Assessment of the Skin Sensitization Potential of Chemicals

    PubMed Central

    Wong, Chin Lin; Lam, Ai-Leen; Smith, Maree T.; Ghassabian, Sussan

    2016-01-01

    The direct peptide reactivity assay (DPRA) is a validated method for in vitro assessment of the skin sensitization potential of chemicals. In the present work, we describe a peptide reactivity assay using 96-well plate format and systematically identified the optimal assay conditions for accurate and reproducible classification of chemicals with known sensitizing capacity. The aim of the research is to ensure that the analytical component of the peptide reactivity assay is robust, accurate, and reproducible in accordance with criteria that are used for the validation of bioanalytical methods. Analytical performance was evaluated using quality control samples (QCs; heptapeptides at low, medium, and high concentrations) and incubation of control chemicals (chemicals with known sensitization capacity, weak, moderate, strong, extreme, and non-sensitizers) with each of three synthetic heptapeptides, viz Cor1-C420 (Ac-NKKCDLF), cysteine- (Ac-RFAACAA), and lysine- (Ac-RFAAKAA) containing heptapeptides. The optimal incubation temperature for all three heptapeptides was 25°C. Apparent heptapeptide depletion was affected by vial material composition. Incubation of test chemicals with Cor1-C420, showed that peptide depletion was unchanged in polypropylene vials over 3-days storage in an autosampler but this was not the case for borosilicate glass vials. For cysteine-containing heptapeptide, the concentration was not stable by day 3 post-incubation in borosilicate glass vials. Although the lysine-containing heptapeptide concentration was unchanged in both polypropylene and borosilicate glass vials, the apparent extent of lysine-containing heptapeptide depletion by ethyl acrylate, differed between polypropylene (24.7%) and glass (47.3%) vials. Additionally, the peptide-chemical complexes for Cor1-C420-cinnamaldehyde and cysteine-containing heptapeptide-2, 4-dinitrochlorobenzene were partially reversible during 3-days of autosampler storage. These observations further highlight

  19. Estimating Skin Cancer Risk: Evaluating Mobile Computer-Adaptive Testing

    PubMed Central

    Djaja, Ngadiman; Janda, Monika; Olsen, Catherine M; Whiteman, David C

    2016-01-01

    Background Response burden is a major detriment to questionnaire completion rates. Computer adaptive testing may offer advantages over non-adaptive testing, including reduction of numbers of items required for precise measurement. Objective Our aim was to compare the efficiency of non-adaptive (NAT) and computer adaptive testing (CAT) facilitated by Partial Credit Model (PCM)-derived calibration to estimate skin cancer risk. Methods We used a random sample from a population-based Australian cohort study of skin cancer risk (N=43,794). All 30 items of the skin cancer risk scale were calibrated with the Rasch PCM. A total of 1000 cases generated following a normal distribution (mean [SD] 0 [1]) were simulated using three Rasch models with three fixed-item (dichotomous, rating scale, and partial credit) scenarios, respectively. We calculated the comparative efficiency and precision of CAT and NAT (shortening of questionnaire length and the count difference number ratio less than 5% using independent t tests). Results We found that use of CAT led to smaller person standard error of the estimated measure than NAT, with substantially higher efficiency but no loss of precision, reducing response burden by 48%, 66%, and 66% for dichotomous, Rating Scale Model, and PCM models, respectively. Conclusions CAT-based administrations of the skin cancer risk scale could substantially reduce participant burden without compromising measurement precision. A mobile computer adaptive test was developed to help people efficiently assess their skin cancer risk. PMID:26800642

  20. Artificial microfluidic skin for in vitro perspiration simulation and testing.

    PubMed

    Hou, Linlin; Hagen, Joshua; Wang, Xiao; Papautsky, Ian; Naik, Rajesh; Kelley-Loughnane, Nancy; Heikenfeld, Jason

    2013-05-21

    To expedite development of any skin wearable material, product, or device, an artificial perspiration (sweat) simulator can provide improved ease, cost, control, flexibility, and reproducibility in comparison to human or animal tests. Reported here is a human perspiration mimicking device including microreplicated skin-texture. A bottom 0.2 μm track etched polycarbonate membrane layer provides flow-rate control while a top photo-curable layer provides skin-like features such as sweat pore density, hydrophobicity, and wetting hysteresis. Key capabilities of this sweat simulator include: constant 'sweat' rate density without bubble-point variation even down to ~1 L h(-1) m(-2); replication of the 2 pores mm(-2) pore-density and the ~50 μm texture of human skin; simple gravity-fed flow control; low-cost and disposable construction. PMID:23576120

  1. Chemical reactivity indices and mechanism-based read-across for non-animal based assessment of skin sensitisation potential.

    PubMed

    Roberts, David W; Aptula, Aynur O; Patlewicz, Grace; Pease, Camilla

    2008-05-01

    The skin sensitisation potential of chemicals is currently assessed using in vivo methods where the murine local lymph node assay (LLNA) is typically the method of first choice. Current regulatory initiatives are driving the impetus for the use of in vitro/in silico alternative approaches to provide the relevant information needed for the effective assessment of skin sensitisation, for both hazard characterisation and risk assessment purposes. A chemical must undergo a number of steps for it to induce skin sensitisation but the main determining step is formation of a stable covalent association with carrier protein. The ability of a chemical to react covalently with carrier protein nucleophiles relates to both its electrophilic reactivity and its hydrophobicity. This paper focuses on quantitative indices of electrophilic reactivity with nucleophiles, in a chemical mechanism-of-action context, and compares and contrasts the experimental approaches available to generate reactivity data that are suitable for mathematical modelling and making predictions of skin sensitisation potential, using new chemistry data correlated against existing in vivo bioassay data. As such, the paper goes on to describe an illustrative example of how quantitative kinetic measures of reactivity can be usefully and simply applied to perform mechanism-based read-across that enables hazard characterisation of skin sensitisation potential. An illustration of the types of quantitative mechanistic models that could be built using databases of kinetic measures of reactivity, hydrophobicity and existing in vivo bioassay data is also given. PMID:17703503

  2. Comparison between sensitivity of autologous skin serum test and autologous plasma skin test in patients with Chronic Idiopathic Urticaria for detection of antibody against IgE or IgE receptor (FcεRIα).

    PubMed

    Sajedi, Vahid; Movahedi, Masoud; Aghamohammadi, Asghar; Aghamohamadi, Asghar; Gharagozlou, Mohammad; Ghareguzlou, Mohammad; Shafiei, Alireza; Soheili, Habib; Sanajian, Nahal

    2011-06-01

    Intradermal injection of autologous serum and plasma elicit a cutaneous reactivity in almost 45-60% of patients with Chronic Idiopathic Urticaria (CIU). This reactivity is associated with the presence of auto antibodies against IgE or IgE receptors. This study was carried out to compare the cutaneous reactivity of autologous serum and plasma skin tests in a series of patients with CIU for diagnosis of auto antibodies against IgE or IgE receptor. Fifty eight patients with CIU were injected intradermally with autologous serum and plasma (anticoagulated by citrate). Histamine was used as positive control and normal saline as negative control. The study group was checked by routine laboratory tests (CBC, U/A etc), allergens with skin prick tests, and serum IgE level, and auto antibodies against thyroid as well. Duration of urticaria was another factor which was assessed.There was no significant difference between positive ASST and positive APST patients for the above mentioned tests. 77.6% of the patients were Positive for APST and 65.5% were ASST positive. Duration of urticaria was longer in patients with positive ASST and APST than ASST and APST negative patients, although the difference was not statistically significant.Autologus serum skin test (ASST) and autologous plasma skin test (APST) could be used for estimation of duration and severity of urticaria and planning for the treatment. PMID:21625019

  3. Improved wheal detection from skin prick test images

    NASA Astrophysics Data System (ADS)

    Bulan, Orhan

    2014-03-01

    Skin prick test is a commonly used method for diagnosis of allergic diseases (e.g., pollen allergy, food allergy, etc.) in allergy clinics. The results of this test are erythema and wheal provoked on the skin where the test is applied. The sensitivity of the patient against a specific allergen is determined by the physical size of the wheal, which can be estimated from images captured by digital cameras. Accurate wheal detection from these images is an important step for precise estimation of wheal size. In this paper, we propose a method for improved wheal detection on prick test images captured by digital cameras. Our method operates by first localizing the test region by detecting calibration marks drawn on the skin. The luminance variation across the localized region is eliminated by applying a color transformation from RGB to YCbCr and discarding the luminance channel. We enhance the contrast of the captured images for the purpose of wheal detection by performing principal component analysis on the blue-difference (Cb) and red-difference (Cr) color channels. We finally, perform morphological operations on the contrast enhanced image to detect the wheal on the image plane. Our experiments performed on images acquired from 36 different patients show the efficiency of the proposed method for wheal detection from skin prick test images captured in an uncontrolled environment.

  4. Harsh Parenting and Child Externalizing Behavior: Skin Conductance Level Reactivity as a Moderator

    PubMed Central

    Erath, Stephen A.; El-Sheikh, Mona; Cummings, E. Mark

    2010-01-01

    Skin conductance level reactivity (SCLR) was examined as a moderator of the association between harsh parenting and child externalizing behavior. Participants were 251 boys and girls (8–9 years). Mothers and fathers provided reports of harsh parenting and their children’s externalizing behavior; children also provided reports of harsh parenting. SCLR was assessed in response to a socioemotional stress task and a problem-solving challenge task. Regression analyses revealed that the association between harsh parenting and externalizing behavior was stronger among children with lower SCLR, as compared to children with higher SCLR. SCLR may be a more robust moderator among boys compared to girls. Results are discussed with regard to theories on antisocial behavior and multiple-domain models of child development. PMID:19467012

  5. Non-animal test methods for predicting skin sensitization potentials.

    PubMed

    Mehling, Annette; Eriksson, Tove; Eltze, Tobias; Kolle, Susanne; Ramirez, Tzutzuy; Teubner, Wera; van Ravenzwaay, Bennard; Landsiedel, Robert

    2012-08-01

    Contact allergies are complex diseases, and it is estimated that 15-20 % of the general population suffers from contact allergy, with increasing prevalence. Evaluation of the sensitization potential of a substance is usually carried out in animal models. Nowadays, there is much interest in reducing and ultimately replacing current animal tests. Furthermore, as of 2013, the EU has posed a ban on animal testing of cosmetic ingredients that includes skin sensitization. Therefore, predictive and robust in vitro tests are urgently needed. In order to establish alternatives to animal testing, the in vitro tests must mimic the very complex interactions between the sensitizing chemical and the different parts of the immune system. This review article summarizes recent efforts to develop in vitro tests for predicting skin sensitizers. Cell-based assays, in chemico methods and, to a lesser extent, in silico methods are presented together with a discussion of their current status. With considerable progress having been achieved during the last years, the rationale today is that data from different non-animal test methods will have to be combined in order to obtain reliable hazard and potency information on potential skin sensitizers. PMID:22707154

  6. Antioxidant inhibition of skin inflammation induced by reactive oxidants: evaluation of the redox couple dihydrolipoate/lipoate.

    PubMed

    Fuchs, J; Milbradt, R

    1994-01-01

    Reactive oxygen species play an important role in mediating skin inflammation, and antioxidants may provide protection. We investigated the anti-inflammatory activity of natural antioxidants, such as superoxide dismutase, catalase, trolox (a water-soluble tocopherol analog) and the redox couple dihydrolipoate/lipoate in skin. Furthermore we compared the anti-inflammatory potency of natural R and racemic dihydrolipoate, as well as R and S lipoate. Skin inflammation in hairless mice was induced by intradermal injection of the hydrogen peroxide producing enzyme glucose oxidase (GOD) or by topical application of the prooxidant drug anthralin. Intradermal injection of the antioxidants inhibited skin inflammation caused by GOD (catalase, dihydrolipoate) and anthralin (trolox, superoxide dismutase, dihydrolipoate). There was no statistically significant difference between the anti-inflammatory activity of the natural R and racemic dihydrolipoate. R or S lipoate did not inhibit skin inflammation when injected intradermally. In feeding experiments, however, R lipoate significantly inhibited GOD-mediated skin inflammation, while S lipoate was only marginally protective. We conclude that (1) several natural antioxidants such as catalase, superoxide dismutase and dihydrolipoate have anti-inflammatory properties in dermatitis induced by reactive oxidants, (2) lipoate (oxidized dihydrolipoate) has skin anti-inflammatory activity when administered orally and (3) naturally occurring R lipoate is a more potent anti-inflammatory agent than the non-physiological S lipoate. PMID:8054210

  7. Functional testing of topical skin formulations using an optimised ex vivo skin organ culture model.

    PubMed

    Sidgwick, G P; McGeorge, D; Bayat, A

    2016-07-01

    A number of equivalent-skin models are available for investigation of the ex vivo effect of topical application of drugs and cosmaceuticals onto skin, however many have their drawbacks. With the March 2013 ban on animal models for cosmetic testing of products or ingredients for sale in the EU, their utility for testing toxicity and effect on skin becomes more relevant. The aim of this study was to demonstrate proof of principle that altered expression of key gene and protein markers could be quantified in an optimised whole tissue biopsy culture model. Topical formulations containing green tea catechins (GTC) were investigated in a skin biopsy culture model (n = 11). Punch biopsies were harvested at 3, 7 and 10 days, and analysed using qRT-PCR, histology and HPLC to determine gene and protein expression, and transdermal delivery of compounds of interest. Reduced gene expression of α-SMA, fibronectin, mast cell tryptase, mast cell chymase, TGF-β1, CTGF and PAI-1 was observed after 7 and 10 days compared with treated controls (p < 0.05). Histological analysis indicated a reduction in mast cell tryptase and chymase positive cell numbers in treated biopsies compared with untreated controls at day 7 and day 10 (p < 0.05). Determination of transdermal uptake indicated that GTCs were detected in the biopsies. This model could be adapted to study a range of different topical formulations in both normal and diseased skin, negating the requirement for animal models in this context, prior to study in a clinical trial environment. PMID:27086034

  8. Pumpless microfluidic platform for drug testing on human skin equivalents.

    PubMed

    Abaci, Hasan Erbil; Gledhill, Karl; Guo, Zongyou; Christiano, Angela M; Shuler, Michael L

    2015-02-01

    Advances in bio-mimetic in vitro human skin models increase the efficiency of drug screening studies. In this study, we designed and developed a microfluidic platform that allows for long-term maintenance of full thickness human skin equivalents (HSE) which are comprised of both the epidermal and dermal compartments. The design is based on the physiologically relevant blood residence times in human skin tissue and allows for the establishment of an air-epidermal interface which is crucial for maturation and terminal differentiation of HSEs. The small scale of the design reduces the amount of culture medium and the number of cells required by 36 fold compared to conventional transwell cultures. Our HSE-on-a-chip platform has the capability to recirculate the medium at desired flow rates without the need for pump or external tube connections. We demonstrate that the platform can be used to maintain HSEs for three weeks with proliferating keratinocytes similar to conventional HSE cultures. Immunohistochemistry analyses show that the differentiation and localization of keratinocytes was successfully achieved, establishing all sub-layers of the epidermis after one week. Basal keratinocytes located at the epidermal-dermal interface remain in a proliferative state for three weeks. We use a transdermal transport model to show that the skin barrier function is maintained for three weeks. We also validate the capability of the HSE-on-a-chip platform to be used for drug testing purposes by examining the toxic effects of doxorubucin on skin cells and structure. Overall, the HSE-on-a-chip is a user-friendly and cost-effective in vitro platform for drug testing of candidate molecules for skin disorders. PMID:25490891

  9. Validation of artificial skin equivalents as in vitro testing systems

    NASA Astrophysics Data System (ADS)

    Schmitt, Robert; Marx, Ulrich; Walles, Heike; Schober, Lena

    2011-03-01

    With the increasing complexity of the chemical composition of pharmaceuticals, cosmetics and everyday substances, the awareness of potential health issues and long term damages for humanoid organs is shifting into focus. Artificial in vitro testing systems play an important role in providing reliable test conditions and replacing precarious animal testing. Especially artificial skin equivalents ASEs are used for a broad spectrum of studies like penetration, irritation and corrosion of substances. One major challenge in tissue engineering is the qualification of each individual ASE as in vitro testing system. Due to biological fluctuations, the stratum corneum hornified layer of some ASEs may not fully develop or other defects might occur. For monitoring these effects we developed an fully automated Optical Coherence Tomography device. Here, we present different methods to characterize and evaluate the quality of the ASEs based on image and data processing of OCT B-scans. By analysing the surface structure, defects, like cuts or tears, are detectable. A further indicator for the quality of the ASE is the morphology of the tissue. This allows to determine if the skin model has reached the final growth state. We found, that OCT is a well suited technology for automatically characterizing artificial skin equivalents and validating the application as testing system.

  10. Marital Conflict and Risk for Child Maladjustment over Time: Skin Conductance Level Reactivity as a Vulnerability Factor

    ERIC Educational Resources Information Center

    El-Sheikh, Mona; Keller, Peggy S.; Erath, Stephen A.

    2007-01-01

    Skin conductance level reactivity (SCLR) was examined as a longitudinal mediator and moderator of relations between parental marital conflict and psychopathology among children and young adolescents. Participants were 157 boys and girls (M age at T1 = 9.31 years; SD = 1.97); there was a 2-year lag between T1 and T2 assessments. At T1,…

  11. Allergy to aminophylline: lack of predictability by skin testing.

    PubMed

    Kradjan, W A; Lakshminarayan, S

    1981-07-01

    Problems with determining hypersensitivity to aminophylline, ethylenediamine, and theophylline with intradermal skin tests and patch tests are reported in three patients. Three patients were tested with intradermal injections of 0.9% sodium chloride, 1% aminophylline, 1% ethylenediamine, and 0.5% theophylline following apparent allergic reactions to aminophylline. Patch testing using hydrophilic ointment base, 1% aminophylline, 1% ethylenediamine, and 0.5% theophylline was also done. All three patients had no reaction to intradermal sodium chloride or theophylline; all patch tests were negative. The first patient reacted to ethylenediamine strongly and to aminophylline more weakly; punch biopsy of the ethylenediamine reaction site showed a direct toxic effect with no allergic component. Punch biopsy of the aminophylline site showed a typical hypersensitivity reaction. Two concentrations (0.5% and 1.0%) of ethylenediamine injection were used to test the second patient, and he reacted to both concentrations but not to any other injections. His positive reactions contained blisters rather than the typical wheal-and-flare reaction of hypersensitivity. The third patient had similar responses including reactions to 0.5% and 0.1% ethylenediamine (he was not tested with 1% ethylenediamine). Skin testing may be of value in predicting aminophylline or ethylenediamine allergy, but the nonspecific toxic effect of ethylenediamine makes interpretation difficult. PMID:7258203

  12. Diagnostic performance of the "MESACUP anti-Skin profile TEST".

    PubMed

    Horváth, Orsolya N; Varga, Rita; Kaneda, Makoto; Schmidt, Enno; Ruzicka, Thomas; Sárdy, Miklós

    2016-02-01

    The "MESACUP anti-Skin profile TEST" is a new, commercially available ELISA kit to detect circulating IgG autoantibodies against desmoglein 1, desmoglein 3, BP180, BP230, and type VII collagen, both simultaneously and more rapidly than previous assays. The aim of this study was to evaluate the diagnostic accuracy of this kit for the diagnosis of pemphigus foliaceus, pemphigus vulgaris, bullous pemphigoid and epidermolysis bullosa acquisita. Dual-centre retrospective study in which 138 patients with autoimmune blistering diseases were compared to 40 controls Using the MESACUP anti-Skin profile TEST, both sensitivities and specificities for desmoglein 1, desmoglein 3, BP180, BP230, and type VII collagen autoantibodies were similar to those obtained using previous, specific ELISA systems and 88% of the results were concordant without any significant difference. The MESACUP anti-Skin profile TEST had a similar performance to previously produced ELISA systems. The novel kit can be used for rapid diagnosis of most common autoimmune blistering diseases and is especially suitable for identifying overlapping disorders. PMID:26771500

  13. Reactivity test between beryllium and copper

    SciTech Connect

    Kawamura, H.; Kato, M.

    1995-09-01

    Beryllium has been expected for using as plasma facing material on ITER. And, copper alloy has been proposed as heat sink material behind plasma facing components. Therefore, both materials must be joined. However, the elementary process of reaction between beryllium and copper alloy does not clear in detail. For example, other authors reported that beryllium reacted with copper at high temperature, but it was not obvious about the generation of reaction products and increasing of the reaction layer. In the present work, from this point, for clarifying the elementary process of reaction between beryllium and copper, the out-of-pile compatibility tests were conducted with diffusion couples of beryllium and copper which were inserted in the capsule filled with high purity helium gas (6N). Annealing temperatures were 300, 400, 500, 600 and 700{degrees}C, and annealing periods were 100, 300 and 1000h. Beryllium specimens were hot pressed beryllium, and copper specimens were OFC (Oxygen Free Copper).

  14. Structural modification of the skin barrier by OH radicals: a reactive molecular dynamics study for plasma medicine

    NASA Astrophysics Data System (ADS)

    Van der Paal, J.; Verlackt, C. C.; Yusupov, M.; Neyts, E. C.; Bogaerts, A.

    2015-04-01

    While plasma treatment of skin diseases and wound healing has been proven highly effective, the underlying mechanisms, and more generally the effect of plasma radicals on skin tissue, are not yet completely understood. In this paper, we perform ReaxFF-based reactive molecular dynamics simulations to investigate the interaction of plasma generated OH radicals with a model system composed of free fatty acids, ceramides, and cholesterol molecules. This model system is an approximation of the upper layer of the skin (stratum corneum). All interaction mechanisms observed in our simulations are initiated by H-abstraction from one of the ceramides. This reaction, in turn, often starts a cascade of other reactions, which eventually lead to the formation of aldehydes, the dissociation of ceramides or the elimination of formaldehyde, and thus eventually to the degradation of the skin barrier function.

  15. Oral Toxicity Study and Skin Sensitization Test of a Cricket.

    PubMed

    Ryu, Hyeon Yeol; Lee, Somin; Ahn, Kyu Sup; Kim, Hye Jin; Lee, Sang Sik; Ko, Hyuk Ju; Lee, Jin Kyu; Cho, Myung-Haing; Ahn, Mi Young; Kim, Eun Mi; Lim, Jeong Ho; Song, Kyung Seuk

    2016-04-01

    Crickets have been attracting considerable interest in the field of nutrition and toxicology due to the global exhaustion of food resulting from a growing population. The cricket is normally eaten in several countries after roasting, similar to the grasshopper; however, safety evaluation data on cricket powder is limited. Here, we performed general toxicity studies of cricket powder including a single, 2-week repeated dose range evaluation test, a 13-week repeated oral dose toxicity test in Sprague-Dawley rats, a single oral dose toxicity test in Beagle dogs, and a skin sensitization test in guinea pigs following the Organization for Economic Cooperation and Development test guidelines 406 and 408 in addition to Good Laboratory Practice. To investigate the NOAEL and target organs of cricket powder, Sprague-Dawley rats were allocated to 4 groups: vehicle control, 1,250 mg/kg, 2,500 mg/kg, 5,000 mg/kg dose test groups and cricket powder was administered over 13 weeks after single dose and dose range finding studies in rats based on the results of the single oral administration toxicity study in rats and Beagle dogs. The results of the study showed that the NOAEL of cricket powder was over 5,000 mg/kg for both sexes of rats without adverse effects in a 13-week repeated oral toxicity study and there was no skin hypersensitivity reaction. Therefore, our results reveal that crickets can be widely used as a new substitute food or nutrient resource. PMID:27123167

  16. Oral Toxicity Study and Skin Sensitization Test of a Cricket

    PubMed Central

    Ryu, Hyeon Yeol; Lee, Somin; Ahn, Kyu Sup; Kim, Hye Jin; Lee, Sang Sik; Ko, Hyuk Ju; Lee, Jin Kyu; Cho, Myung-Haing; Ahn, Mi Young; Kim, Eun Mi; Lim, Jeong Ho; Song, Kyung Seuk

    2016-01-01

    Crickets have been attracting considerable interest in the field of nutrition and toxicology due to the global exhaustion of food resulting from a growing population. The cricket is normally eaten in several countries after roasting, similar to the grasshopper; however, safety evaluation data on cricket powder is limited. Here, we performed general toxicity studies of cricket powder including a single, 2-week repeated dose range evaluation test, a 13-week repeated oral dose toxicity test in Sprague-Dawley rats, a single oral dose toxicity test in Beagle dogs, and a skin sensitization test in guinea pigs following the Organization for Economic Cooperation and Development test guidelines 406 and 408 in addition to Good Laboratory Practice. To investigate the NOAEL and target organs of cricket powder, Sprague-Dawley rats were allocated to 4 groups: vehicle control, 1,250 mg/kg, 2,500 mg/kg, 5,000 mg/kg dose test groups and cricket powder was administered over 13 weeks after single dose and dose range finding studies in rats based on the results of the single oral administration toxicity study in rats and Beagle dogs. The results of the study showed that the NOAEL of cricket powder was over 5,000 mg/kg for both sexes of rats without adverse effects in a 13-week repeated oral toxicity study and there was no skin hypersensitivity reaction. Therefore, our results reveal that crickets can be widely used as a new substitute food or nutrient resource. PMID:27123167

  17. Apparatus for testing skin samples or the like

    DOEpatents

    Holland, J.M.

    1982-08-31

    An apparatus for testing the permeability of living skin samples has a flat base with a plurality of sample-holding cavities formed in its upper surface, the samples being placed in counterbores in the cavities with the epidermis uppermost. O-rings of Teflon washers are respectively placed on the samples and a flat cover is connected to the base to press the rings against the upper surfaces of the samples. Media to maintain tissue viability and recovery of metabolites is introduced into the lower portion of the sample-holding cavities through passages in the base. Test materials are introduced through holes in the cover plate after assembly of the chamber.

  18. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false C-reactive protein immuno-logical test system. 866....5270 C-reactive protein immuno-logical test system. (a) Identification. A C-reactive protein... the C-reactive protein in serum and other body fluids. Measurement of C-reactive protein aids...

  19. Skin Conductance Level Reactivity Moderates the Association Between Harsh Parenting and Growth in Child Externalizing Behavior

    PubMed Central

    Erath, Stephen A.; El-Sheikh, Mona; Hinnant, J. Benjamin; Cummings, E. Mark

    2011-01-01

    Skin conductance level reactivity (SCLR) was examined as a moderator of the association between harsh parenting at age 8 years and growth in child externalizing behavior from age 8 to age 10 (N = 251). Mothers and fathers provided reports of harsh parenting and their children’s externalizing behavior; children also provided reports of harsh parenting. SCLR was assessed in response to a socioemotional stress task and a problem-solving challenge task. Latent growth modeling revealed that boys with higher harsh parenting in conjunction with lower SCLR exhibited relatively high and stable levels of externalizing behavior during late childhood. Boys with higher harsh parenting and higher SCLR exhibited relatively low to moderate levels of externalizing behavior at age 8, but some results suggested that their externalizing behavior increased over time, approaching the same levels as boys with higher harsh parenting and lower SCLR by age 10. For the most part, girls and boys with lower harsh parenting were given relatively low and stable ratings of externalizing behavior throughout late childhood. Results are discussed from a developmental psychopathology perspective with reference to models of antisocial behavior in childhood. PMID:21142369

  20. Peptide reactivity associated with skin sensitization: The QSAR Toolbox and TIMES compared to the DPRA.

    PubMed

    Urbisch, D; Honarvar, N; Kolle, S N; Mehling, A; Ramirez, T; Teubner, W; Landsiedel, R

    2016-08-01

    The molecular initiating event (MIE) of skin sensitization is the binding of a hapten to dermal proteins. This can be assessed using the in chemico direct peptide reactivity assay (DPRA) or in silico tools such as the QSAR Toolbox and TIMES SS. In this study, the suitability of these methods was analyzed by comparing their results to in vivo sensitization data of LLNA and human studies. Compared to human data, 84% of non-sensitizers and sensitizers yielded consistent results in the DPRA. In silico tools resulted in 'no alert' for 83%-100% of the non-sensitizers, but alerted only 55%-61% of the sensitizers. The inclusion of biotic and abiotic transformation simulations yielded more alerts for sensitizers, but simultaneously dropped the number of non-alerted non-sensitizers. In contrast to the DPRA, in silico tools were more consistent with results of the LLNA than human data. Interestingly, the new "DPRA profilers" (QSAR Toolbox) provided unsatisfactory results. Additionally, the results were combined in the '2 out of 3' prediction model with in vitro data derived from LuSens and h-CLAT. Using DPRA results, the model identified 90% of human sensitizers and non-sensitizers; using in silico results (including abiotic and biotic activations) instead of DPRA results led to a comparable high predictivity. PMID:27090964

  1. Skin Conductance Level Reactivity Moderates the Association Between Parental Psychological Control and Relational Aggression in Emerging Adulthood.

    PubMed

    Wagner, Caitlin R; Abaied, Jamie L

    2016-04-01

    When studying factors that may heighten risk for relational aggression in youth, it is important to consider characteristics of both the individual and their environment. This research examined the associations between parental psychological control and reactive and proactive relational aggression in emerging adults in college. Given that sympathetic nervous system (SNS) activation may underlie differences between reactive and proactive aggression and has been shown to moderate the effects of parenting on youth development, the moderating role of SNS reactivity [indexed by skin conductance level reactivity (SCLR)] was also examined. Emerging adults (N = 180; 77.2 % female) self-reported on perceptions of parental psychological control and reactive and proactive relational aggression. SCLR was assessed in response to an interpersonal laboratory challenge task. Parental psychological control was positively associated with reactive relational aggression only for emerging adults who exhibited high SCLR. Parental psychological control was positively associated with proactive relational aggression only among emerging adults who showed low SCLR. This study extends previous research on parenting and aggression and suggests that parental psychological control is differentially associated with reactive versus proactive relational aggression, depending on emerging adults' SCLR to interpersonal stress. PMID:26762376

  2. Pharmacy-based skin-testing program in a community hospital.

    PubMed

    Clyne, K E; Ternes, R L

    1996-09-01

    The establishment of a pharmacy-based skin-testing program at a community hospital is described. Problems with existing skin testing were brought to the attention of the pharmacy and therapeutics committee, which decided that one group of caregivers within the hospital should be chosen and trained to perform skin testing. A problem-solving team identified specific problems and developed solutions. The top four causes of the skin-testing problems were failure to follow procedure, inaccurate reading of tests, failure to report positive results, and failure to document results. Groups within the hospital who might perform skin testing were assessed according to several criteria; the pharmacy staff was selected because of ease of notification, availability, and ability to conduct follow-through (reading, documenting, and reporting results). Other improvements were step-by-step instructions for all phases of skin testing, a portable skin-test supply kit, and a skin-test record form to be placed in the physician progress notes. Pharmacists were trained by the employee health nurse. Pharmacist skin testing began in March 1995. Pharmacists administered tests to 93 inpatients and about 250 employees during the first 13 months of the program, and no problems were reported. Establishment of a pharmacy-based skin-testing program improved the quality of inpatient skin testing and enabled pharmacists to increase their role in patient care. PMID:8870893

  3. A dataset on 145 chemicals tested in alternative assays for skin sensitization undergoing prevalidation.

    PubMed

    Natsch, Andreas; Ryan, Cindy A; Foertsch, Leslie; Emter, Roger; Jaworska, Joanna; Gerberick, Frank; Kern, Petra

    2013-11-01

    Skin sensitization is a key endpoint for cosmetic ingredients, with a forthcoming ban for animal testing in Europe. Four alternative tests have so far been submitted to ECVAM prevalidation: (i) MUSST and (ii) h-Clat assess surface markers on dendritic cell lines, (iii) the direct peptide reactivity assay (DPRA) measures reactivity with model peptides and (iv) the KeratinoSens(TM) assay which is based on detection of Nrf2-induced luciferase. It is anticipated that only an integrated testing strategy (ITS) based on a battery of tests might give a full replacement providing also a sensitization potency assessment, but this concept should be tested with a data-driven analysis. Here we report a database on 145 chemicals reporting the quantitative endpoints measured in a U937- test, the DPRA and KeratinoSens(TM) . It can serve to develop data-driven ITS approaches as we show in a parallel paper and provides a view as to the current ability to predict with in vitro tests as we are entering 2013. It may also serve as reference database when benchmarking new molecules with in vitro based read-across and find use as a reference database when evaluating new tests. The tests and combinations thereof were evaluated for predictivity, and overall a similar predictivity was found as before on three-fold smaller datasets. Analysis of the dose-response parameters of the individual tests indicates a correlation to sensitization potency. Detailed analysis of chemicals false-negative and false-positive in two tests helped to define limitations in the tests but also in the database derived from animal studies. PMID:23576290

  4. Sleep Deprived and Sweating It Out: The Effects of Total Sleep Deprivation on Skin Conductance Reactivity to Psychosocial Stress

    PubMed Central

    Liu, Jean C.J.; Verhulst, Silvan; Massar, Stijn A.A.; Chee, Michael W.L.

    2015-01-01

    Study Objectives: We examined how sleep deprivation alters physiological responses to psychosocial stress by evaluating changes in skin conductance. Design: Between-subjects design with one group allocated to 24 h of total sleep deprivation and the other to rested wakefulness. Setting: The study took place in a research laboratory. Participants: Participants were 40 healthy young adults recruited from a university. Interventions: Sleep deprivation and feedback. Measurements and Results: Electrodermal activity was monitored while participants completed a difficult perceptual task with false feedback. All participants showed increased skin conductance levels following stress. However, compared to well-rested participants, sleep deprived participants showed higher skin conductance reactivity with increasing stress levels. Conclusions: Our results suggest that sleep deprivation augments allostatic responses to increasing psychosocial stress. Consequentially, we propose sleep loss as a risk factor that can influence the pathogenic effects of stress. Citation: Liu JC, Verhulst S, Massar SA, Chee MW. Sleep deprived and sweating it out: the effects of total sleep deprivation on skin conductance reactivity to psychosocial stress. SLEEP 2015;38(1):155–159. PMID:25325448

  5. Assessment of Pre- and Pro-haptens Using Nonanimal Test Methods for Skin Sensitization.

    PubMed

    Urbisch, Daniel; Becker, Matthias; Honarvar, Naveed; Kolle, Susanne Noreen; Mehling, Annette; Teubner, Wera; Wareing, Britta; Landsiedel, Robert

    2016-05-16

    Because of ethical and regulatory reasons, several nonanimal test methods to assess the skin sensitization potential of chemicals have been developed and validated. In contrast to in vivo methods, they lack or provide limited metabolic capacity. For this reason, identification of pro-haptens but also pre-haptens, which require molecular transformations to gain peptide reactivity, is a challenge for these methods. In this study, 27 pre- and pro-haptens were tested using nonanimal test methods. Of these, 18 provided true positive results in the direct peptide reactivity assay (DPRA; sensitivity of 67%), although lacking structural alerts for direct peptide reactivity. The reaction mechanisms leading to peptide depletion in the DPRA were therefore elucidated using mass spectrometry. Hapten-peptide adducts were identified for 13 of the 18 chemicals indicating that these pre-haptens were activated and that peptide binding occurred. Positive results for five of the 18 chemicals can be explained by dipeptide formations or the oxidation of the sulfhydryl group of the peptide. Nine of the 27 chemicals were tested negative in the DPRA. Of these, four yielded true positive results in the keratinocyte and dendritic cell based assays. Likewise, 16 of the 18 chemicals tested positive in the DPRA were also positive in either one or both of the cell-based assays. A combination of DPRA, KeratinoSens, and h-CLAT used in a 2 out of 3 weight of evidence (WoE) approach identified 22 of the 27 pre- and pro-haptens correctly (sensitivity of 81%), exhibiting a similar sensitivity as for directly acting haptens. This analysis shows that the combination of in chemico and in vitro test methods is suitable to identify pre-haptens and the majority of pro-haptens. PMID:27070937

  6. Decreased Serum Epinephrine in Children With Positive Skin Prick Test

    PubMed Central

    Hong, Seok-Chan; Suh, Jeffrey D.; Chung, Sochung; Lee, Seung-Hoon; Choi, Ji Ho; Oh, Jeong In; Kim, In-Tae; Kim, Jin Kook

    2015-01-01

    Objectives To evaluate the association between catecholamine levels and skin prick test results among children. Methods Two hundred eight first grade children from one elementary school were invited to participate in this study. Skin prick test (SPT) for six allergens (2 house dust mites, cat, dog, mugwort, and pollen mixture) was performed, and patient demographic information was recorded. The parents were surveyed using questionnaires about rhinitis-related symptoms. Finally, venous blood sampling was done to measure catecholamine levels (epinephrine, norepinephrine, and dopamine) by high-performance liquid chromatography. Results Out of 208 children, 174 (106 boys and 68 girls) enrolled in this study. Ninety-six of the children (55%) had negative SPT (nonsensitization group), while 78 (45%) had a positive SPT to at least one of six allergens (sensitization group). The diagnosis of chronic rhinitis was more prevalent in the sensitization group (35.9%) than nonsensitization group (26.0%), however the finding was not significant (P=0.186). Epinephrine levels were decreased between the sensitization group compared to the nonsensitization group (P=0.004). There was no difference in norepinephrine and dopamine levels (P>0.05). Conclusion Epinephrine levels are lower in children with positive SPT compared to controls, however, the level of the catecholamine was not associated with the presence or absence of rhinitis symptoms. PMID:26622958

  7. 78 FR 68076 - Request for Information on Alternative Skin Sensitization Test Methods and Testing Strategies and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-13

    ...The Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) is developing a U.S. plan for the evaluation of alternative skin sensitization test methods and testing strategies. The National Toxicology Program (NTP) Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) requests information that ICCVAM might use to develop this plan and......

  8. CHEMICAL REACTIVITY TEST: Assessing Thermal Stability and Chemical Compatibility

    SciTech Connect

    Koerner, J; Tran, T; Gagliardi, F; Fontes, A

    2005-04-21

    The thermal stability of high explosive (HE) and its compatibility with other materials are of critical importance in storage and handling practices. These properties are measured at Lawrence Livermore National Laboratory using the chemical reactivity test (CRT). The CRT measures the total amount of gas evolved from a material or combination of materials after being heat treated for a designated period of time. When the test result is compared to a threshold value, the relative thermal stability of an HE or the compatibility of an HE with other materials is determined. We describe the CRT testing apparatus, the experimental procedure, and the comparison methodology and provide examples and discussion of results.

  9. Freeze-drying as a preserving preparation technique for in vitro testing of human skin.

    PubMed

    Franzen, Lutz; Vidlářová, Lucie; Kostka, Karl-Heinz; Schaefer, Ulrich F; Windbergs, Maike

    2013-01-01

    In vitro testing of drugs with excised human skin is a valuable prerequisite for clinical studies. However, the analysis of excised human skin presents several obstacles. Ongoing drug diffusion, microbial growth and changes in hydration state influence the results of drug penetration studies. In this work, we evaluate freeze-drying as a preserving preparation method for skin samples to overcome these obstacles. We analyse excised human skin before and after freeze-drying and compare these results with human skin in vivo. Based on comprehensive thermal and spectroscopic analysis, we demonstrate comparability to in vivo conditions and exclude significant changes within the skin samples due to freeze-drying. Furthermore, we show that freeze-drying after skin incubation with drugs prevents growth of drug crystals on the skin surface due to drying effects. In conclusion, we introduce freeze-drying as a preserving preparation technique for in vitro testing of human skin. PMID:23278895

  10. A fluorescence high throughput screening method for the detection of reactive electrophiles as potential skin sensitizers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Skin sensitization is an important toxicological end-point in the risk assessment of chemical allergens. Because of the complexity of the biological mechanisms associated with skin sensitization integrated approaches combining different chemical, biological and in silico methods are recommended to r...

  11. Evaluation of leishmanin skin test in Indian visceral leishmaniasis.

    PubMed

    Gidwani, Kamlesh; Rai, Madhukar; Chakravarty, Jaya; Boelaert, Marleen; Sundar, Shyam

    2009-04-01

    We evaluated the performance of the leishmanin skin test (LST) in 50 patients with visceral leishmaniasis (VL), 124 cured VL patients at different time intervals, 125 healthy controls from an endemic region (HEC), and 14 healthy controls from a non-endemic region (NEHC). The leishmanin antigen used was based on Leishmania major and was obtained from the Pasteur Institute (Iran). A positive LST was found in 14.0% of patients with active VL, 40.3% of cured patients, 21.6% of HECs, and 0% in NEHCs. The 14% positivity in patients with active VL conflicts with the widely held opinion that such patients should be negative because of anergy. Also, a lack of sensitivity of the LST was observed in cured VL patients. An LST antigen produced from L. donovani strains from India should be explored. PMID:19346376

  12. Small-Scale Shock Reactivity and Internal Blast Test

    NASA Astrophysics Data System (ADS)

    Granholm, R. H.; Sandusky, H. W.

    2006-07-01

    Explosives react from a strong shock, even in quantities too small for detonation. The potential for a new material to be an explosive can be evaluated from this shock reactivity. The recently developed small-scale shock reactivity test (SSRT) uses very high confinement to allow prompt reactions to occur in less than half-gram samples well below critical diameter. Early and late-time reactions are simultaneously measured from a single sample subjected to the output from an RP-80 detonator. Prompt reactions are quantified by a dent in a soft aluminum witness block, while later reactions, such as from fuel/air combustion, are measured by recording blast pressure. Internal blast quasi-static pressure is obtained by confining the sample apparatus within a three-liter chamber. Late-time reaction effects of plastics, and results from HMX, HMX/Aluminum, and a plastic-bonded explosive (PBX) are reported.

  13. An integrated testing strategy for in vitro skin corrosion and irritation assessment using SkinEthic™ Reconstructed Human Epidermis.

    PubMed

    Alépée, Nathalie; Grandidier, Marie-Hélène; Tornier, Carine; Cotovio, José

    2015-10-01

    The SkinEthic™ Reconstructed Human Epidermis (RHE) method has been formally adopted for the regulatory assessment of skin irritation (OECD TG 439) and corrosion (OECD TG 431). Recently, the OECD adopted an Integrated Approach on Testing and Assessment (IATA) for skin corrosion and skin irritation (OECD GD 203), which provides guidance on the integration of existing and new information in a modular approach for classification and labelling. The present study aimed to evaluate the use of the SkinEthic™ RHE model within the proposed OECD IATA. Data on 86 substances were integrated in a bottom-up and top-down testing strategy to assess their capacity for EU CLP and UN GHS classifications. For EU CLP, strategies showed an accuracy of 84.8% to discriminate non-classified from classified substances, 94.4% to discriminate corrosive from non-corrosive substances, and 68.5% to discriminate the four (sub)-categories. For UN GHS, strategies showed an accuracy of 89.5% to discriminate non-classified from classified substances, 93.4% to discriminate corrosive from non-corrosive substances, and 74.2% to discriminate four GHS (sub)-categories (excluding Category 3). In conclusion, the integration of SkinEthic™ RHE irritation and corrosion data in a bottom-up and top-down testing strategy allows the classification of substances according to EU CLP and UN GHS. PMID:26187475

  14. EVALUATION OF DIAGNOSTIC ACCURACY OF THE COMPARATIVE TUBERCULIN SKIN TEST IN REHABILITANT BORNEAN ORANGUTANS (PONGO PYGMAEUS).

    PubMed

    Dench, Rosalie; Sulistyo, Fransiska; Fahroni, Agus; Philippa, Joost

    2015-12-01

    The tuberculin skin test (TST) has been the mainstay of tuberculosis (TB) testing in primates for decades, but its interpretation in orangutans (Pongo spp.) is challenging, because many animals react strongly, without evidence of infection with Mycobacterium tuberculosis complex. One explanation is cross-reactivity with environmental nontuberculous mycobacteria (NTM). The use of a comparative TST (CTST), comparing reactivity to avian (representing NTM) and bovine (representing tuberculous mycobacteria) tuberculins aids in distinguishing cross-reactivity due to sensitization by NTM from shared antigens. The specificity of the TST can be increased with the use of CTST. We considered three interpretations of the TST in rehabilitant Bornean orangutans ( Pongo pygmaeus ) using avian purified protein derivative (APPD; 25,000 IU/ml) and two concentrations of bovine purified protein derivative (BPPD; 100,000 and 32,500 IU/ml). The tests were evaluated for their ability to identify accurately seven orangutans previously diagnosed with and treated for TB from a group of presumed negative individuals (n = 288 and n = 161 for the two respective BPPD concentrations). BPPD at 32,500 IU/ml had poor diagnostic capacity, whereas BPPD at 100,000 IU/ml performed better. The BPPD-only interpretation had moderate sensitivity (57%) and poor specificity (40%) and accuracy (41%). The comparative interpretation at 72 hr had similar sensitivity (57%) but improved specificity (95%) and accuracy (94%). However, best results were obtained by a comparative interpretation incorporating the 48- and 72-hr scores, which had good sensitivity (86%), specificity (95%) and accuracy (95%). These data reinforce recommendations that a CTST be used in orangutans and support the use of APPD at 25,000 IU/ml and BPPD at 100,000 IU/ml. The highest score at each site from the 48- and 72-hr checks should be considered the result for that tuberculin. If the bovine result is greater than the avian result, the

  15. Prospective multicentre study of the U-SENS test method for skin sensitization testing.

    PubMed

    Alépée, N; Piroird, C; Aujoulat, M; Dreyfuss, S; Hoffmann, S; Hohenstein, A; Meloni, M; Nardelli, L; Gerbeix, C; Cotovio, J

    2015-12-25

    The U-SENS™ is a test method based on the human myeloid U937 cell line to assess the skin sensitisation potential of substances. To demonstrate its robustness, a multicentre validation study with four laboratories testing 24 coded substances has been conducted according to internationally agreed principles. The primary objective of the study was to enlarge the U-SENS™'s reproducibility database. Secondary objectives were to provide additional evidence on its transferability and its predictive capability. Reproducibility within laboratories was approximately 92%, while the reproducibility between laboratories was 87.5%. Predictivity for the 24 validation substances was high, with sensitivity, specificity and accuracy being on average at least 93.8%. Similar performances are obtained for 38 substances when combining the study results with those of an earlier multicentre study, as well as with an automated version of the U-SENS™. With reliability and relevance similar to comparable non-animal skin sensitisation test methods, which have achieved regulatory acceptance, it is concluded that the U-SENS™ is a well reproducible and predictive test method. This profiles the U-SENS™ as a valuable addition to the suite of non-animal testing methods for skin sensitisation with the potential to significantly contribute to the development of integrated testing strategies. PMID:26439184

  16. Grape seed proanthocyanidins reactivate silenced tumor suppressor genes in human skin cancer cells by targeting epigenetic regulators

    SciTech Connect

    Vaid, Mudit; Prasad, Ram; Singh, Tripti; Jones, Virginia; Katiyar, Santosh K.

    2012-08-15

    Grape seed proanthocyanidins (GSPs) have been shown to have anti-skin carcinogenic effects in in vitro and in vivo models. However, the precise epigenetic molecular mechanisms remain unexplored. This study was designed to investigate whether GSPs reactivate silenced tumor suppressor genes following epigenetic modifications in skin cancer cells. For this purpose, A431 and SCC13 human squamous cell carcinoma cell lines were used as in vitro models. The effects of GSPs on DNA methylation, histone modifications and tumor suppressor gene expressions were studied in these cell lines using enzyme activity assays, western blotting, dot-blot analysis and real-time polymerase chain reaction (RT-PCR). We found that treatment of A431 and SCC13 cells with GSPs decreased the levels of: (i) global DNA methylation, (ii) 5-methylcytosine, (iii) DNA methyltransferase (DNMT) activity and (iv) messenger RNA (mRNA) and protein levels of DNMT1, DNMT3a and DNMT3b in these cells. Similar effects were noted when these cancer cells were treated identically with 5-aza-2′-deoxycytidine, an inhibitor of DNA methylation. GSPs decreased histone deacetylase activity, increased levels of acetylated lysines 9 and 14 on histone H3 (H3-Lys 9 and 14) and acetylated lysines 5, 12 and 16 on histone H4, and reduced the levels of methylated H3-Lys 9. Further, GSP treatment resulted in re-expression of the mRNA and proteins of silenced tumor suppressor genes, RASSF1A, p16{sup INK4a} and Cip1/p21. Together, this study provides a new insight into the epigenetic mechanisms of GSPs and may have significant implications for epigenetic therapy in the treatment/prevention of skin cancers in humans. -- Highlights: ►Epigenetic modulations have been shown to have a role in cancer risk. ►Proanthocyanidins decrease the levels of DNA methylation and histone deacetylation. ►Proanthocyanidins inhibit histone deacetylase activity in skin cancer cells. ►Proanthocyanidins reactivate tumor suppressor genes in skin

  17. Absence of induction of enhanced reactivation of herpes simplex virus in cells from xeroderma pigmentosum patients without skin cancer

    SciTech Connect

    Abrahams, P.J.; van der Kleij, A.A.; Schouten, R.; van der Eb, A.J.

    1988-11-01

    The time course of appearance of enhanced reactivation (ER) and enhanced mutagenesis (EM) of herpes simplex virus type 1 were studied in UV-irradiated stationary cultures of xeroderma pigmentosum (XP) fibroblasts. In some of the XP cells EM followed similar kinetics of appearance as ER. Maximal activities occurred when infection was delayed 1 or 2 days after cell treatment. However, in certain XP cells only induction of the EM response was observed, whereas ER was absent. Interestingly, the latter XP cells had been obtained from patients who had not yet developed skin cancer at the time they were described in the literature, whereas the former XP patients had already developed skin tumors. This suggests that the ER response may somehow be involved in the process of oncogenic transformation. Dose-response studies of ER in XP cells from tumor-bearing patients showed that ER is maximally induced with a UV dose of 40 Jm-2 given to the virus. Normal levels of ER were observed in 14 different normal human skin fibroblasts, indicating that the ER- phenotype does not occur in normal cells or at least more rarely than in XP cells.

  18. Sensitivity of BWR (boiling-water reactor) shutdown margin tests to local reactivity anomalies

    SciTech Connect

    Cokinos, D.M.; Carew, J.F.

    1987-06-01

    The purpose of the work summarized in this paper has been to investigate and quantify the sensitivity of both the adjacent-rod and in-sequence Successful Shutdown Margin (SDM) tests to local reactivity anomalies. This was accomplished by introducing reactivity perturbations at selected four-bundle cell locations, and by evaluating their effect on core reactivity in each of the two tests.

  19. Seroepidemiological and leishmanin skin test surveys of visceral leishmaniasis in south and southwest Ethiopia.

    PubMed

    Hailu, A; Berhe, N; Sisay, Z; Abraham, I; Medhin, G

    1996-01-01

    Sero-epidemiological and leishmanin skin test surveys of visceral leishmaniasis were carried out in eight localities of South and Southwest Ethiopia between the July 1989 and June 1992. A total number of 4870 subjects comprising semi-pastoral nomads, peasants and farm labourers were included in the study. Areas of high and low leishmanin skin test positivity were identified, with rates varying from 1.0-80.5%. An enzyme-linked immunosorbent assay was used to determine prevalence of antileishmanial antibodies. The rates varied from 1.8% to 27.8%. Age and sex related serological and leishmanin skin test profiles are described. Correlation analysis of serological and leishmanin skin test was made for data in each locality. The relationships between seroprevalence, leishmanin skin test rates and prevalence of active visceral leishmaniasis and the implications on degrees of endemicity and patterns of transmission are discussed. PMID:8674496

  20. Male infertility testing: reactive oxygen species and antioxidant capacity.

    PubMed

    Ko, Edmund Y; Sabanegh, Edmund S; Agarwal, Ashok

    2014-12-01

    Reactive oxygen species (ROS) are an integral component of sperm developmental physiology, capacitation, and function. Elevated ROS levels, from processes such as infection or inflammation, can be associated with aberrations of sperm development, function, and fertilizing capacity. We review the impact of ROS on sperm physiology, its place in infertility evaluation, the implications for reproductive outcomes, and antioxidant therapy. Our systematic review of PubMed literature from the last 3 decades focuses on the physiology and etiology of ROS and oxidative stress (OS), evaluation of ROS, and antioxidants. ROS is normally produced physiologically and is used to maintain cellular processes such as sperm maturation, capacitation, and sperm-oocyte interaction. When ROS production exceeds the buffering capacity of antioxidants, OS occurs and can have a negative impact on sperm and fertility. ROS and antioxidant capacity testing can potentially add additional prognostic information to standard laboratory testing for the infertile male, although its role as standard part of an evaluation has yet to be determined. Elevated ROS levels have been implicated with abnormal semen parameters and male infertility, but the impact of ROS on fertilization rates and pregnancy is controversial. This is partly because of the lack of consensus on what type of patients may be suitable for ROS testing and assay standardization. Routine ROS testing for the infertile male is not currently recommended. PMID:25458618

  1. Skin testing and erythrocyte sedimentation rate in women undergoing breast biopsy.

    PubMed

    Lane, R; Ungerer, J; Bernene, J; Askenase, P

    The purpose of this study was to determine the utility of skin testing and erythrocyte sedimentation rate (ESR) as measures of immune function in a population undergoing stress. Eight women were tested one week prior to breast biopsy and six were retested at least four weeks later. All biopsies were negative for malignancy. Control subjects were also tested four weeks apart. ESR values were elevated with stress but the magnitude of this effect was small. There were no differences between groups in skin test responses. Skin testing and ESR may have limited usefulness in the study of immune function in populations under stress. PMID:6885263

  2. The usefulness of the validated SkinEthic™ RHE test method to identify skin corrosive UN GHS subcategories.

    PubMed

    Alépée, Nathalie; Robert, Clément; Tornier, Carine; Cotovio, José

    2014-06-01

    The SkinEthic™ Reconstructed Human Epidermis (RHE) test method has been adopted within the context of OECD TG 431 for distinguishing corrosive and non-corrosive chemicals. The EU CLP classification system requires subcategorising of corrosive chemicals into the three UN GHS subcategories 1A, 1B and 1C. Since the SkinEthic™ RHE method was originally validated to discriminate corrosives from non-corrosives, the present study was undertaken to investigate its usefulness to discriminate skin corrosive UN GHS subcategories. In total 84 substances were tested in three independent runs and two prediction models (PM) were assessed, representing a pre-defined validated prediction model (PM-A) and an alternative one defined post-hoc (PM-B). The results obtained with both PM were reproducible, as shown by the ⩾92.9% concordance of classification between runs for discriminating corrosives versus non-corrosives, and the ⩾85% concordance for discriminating the GHS subcategories versus non-corrosives. Moreover results confirmed a high sensitivity of the SkinEthic™ RHE method to predict corrosives (94.9%) and good specificity (⩾73.7%) independent of the PM applied. Regarding the identification of UN GHS corrosive subcategories, PM-A resulted in 86.1% correct classifications of the GHS subcategory 1A. When using the PM-B, the identification of GHS subcategory 1B-and-1C substances improved, with 63.4% correct sub-categorisation. If considering the 30 reference chemicals as recommended in the recently revised OECD TG 431 (2013), PM-A and PM-B achieved 78.9% and 83.3% accuracy respectively for the identification of GHS subcategories and non-corrosives. They correctly predicted 90% of GHS subcategory 1A and 80% of GHS non-corrosive substances independent of the PM used. In conclusion, the SkinEthic™ RHE test method is highly reproducible and sensitive for discriminating corrosive from non-corrosive substances. Furthermore it allows reliable identification of skin

  3. An analysis of skin prick test reactions in 656 asthmatic patients.

    PubMed

    Hendrick, D J; Davies, R J; D'Souza, M F; Pepys, J

    1975-02-01

    Of 656 asthmatic patients referred specifically for allergy assessments, 544 (84 percent) gave positive immediate skin prick tests to at least one of 22 common allergens used routinely. Comparison of these skin test positive patients with the 102 (16 percent) who were skin test negative showed a number of significant differences. The majority of the skin test positive patients (52 percent) were less than 10 years old at the time of onset of the asthma, whereas, of the skin test negative patients, 56 percent were aged over 30 years at the time of onset. Seventy per cent report rhinitis compared with 48 per cent of the skin test negative patients, and 29 per cent reported infantile eczema compared with 9 per cent. Symptoms attributed to house dust, pollens, and animals were noted two to three times more frequently by the skin test positive patients, while corticosteroid drugs had been used more commonly by the skin test negative patients (45 percent compared with 35 percent). No significant differences were observed with the other factors studied, namely, history of urticaria or angio-oedema, family history of "allergic" disease, and awareness of sensitivity to foods, aspirin or penicillin. Prick test reactions in the skin test positive patients were most commonly seen to house dust or the acarine mite, Dermatophagoides farinae (82 percent), followed by pollens (66 percent), animal danders (38 percent), foods (16 percent), Aspergillus fumigatus (16 percent), and other moulds (21 percent). There was a highly significant association of positive history with positive prick test for all allergens studied. PMID:1168378

  4. An analysis of skin prick test reactions in 656 asthmatic patients.

    PubMed Central

    Hendrick, D J; Davies, R J; D'Souza, M F; Pepys, J

    1975-01-01

    Of 656 asthmatic patients referred specifically for allergy assessments, 544 (84 percent) gave positive immediate skin prick tests to at least one of 22 common allergens used routinely. Comparison of these skin test positive patients with the 102 (16 percent) who were skin test negative showed a number of significant differences. The majority of the skin test positive patients (52 percent) were less than 10 years old at the time of onset of the asthma, whereas, of the skin test negative patients, 56 percent were aged over 30 years at the time of onset. Seventy per cent report rhinitis compared with 48 per cent of the skin test negative patients, and 29 per cent reported infantile eczema compared with 9 per cent. Symptoms attributed to house dust, pollens, and animals were noted two to three times more frequently by the skin test positive patients, while corticosteroid drugs had been used more commonly by the skin test negative patients (45 percent compared with 35 percent). No significant differences were observed with the other factors studied, namely, history of urticaria or angio-oedema, family history of "allergic" disease, and awareness of sensitivity to foods, aspirin or penicillin. Prick test reactions in the skin test positive patients were most commonly seen to house dust or the acarine mite, Dermatophagoides farinae (82 percent), followed by pollens (66 percent), animal danders (38 percent), foods (16 percent), Aspergillus fumigatus (16 percent), and other moulds (21 percent). There was a highly significant association of positive history with positive prick test for all allergens studied. Images PMID:1168378

  5. Development of action levels for MED/MPD skin-testing units in ultraviolet phototherapy

    NASA Astrophysics Data System (ADS)

    O'Connor, Una M.; O'Hare, Neil J.

    2003-03-01

    Ultraviolet (UV) Phototherapy is commonly used for treatment of skin diseases such as psoriasis and eczema. Treatment is carried out using UV phototherapy units, exposing all or part of the body for a certain exposure time. Prior to exposure in treatment units, an unaffected area of skin may be tested using UV skin-testing units in order to determine a suitable treatment regime. The exposure time at which barely perceptible erythema has developed is known as the Minimal Erythemal Dose (MED) for UVB therapy and Minimal Phototoxic Dose (MPD) for UVA therapy. This is used to determine the starting dose in the treatment regime. The presence of 'hotspots' and 'coldspots' in UV skin-testing units can result in inaccurate determination of MED/MPD. This could give rise to severe burns during treatment, or in a sub-optimal dose regime being used. Quality assurance protocols for UV phototherapy equipment have recently been developed and these protocols have highlighted the need for action levels for skin-testing units. An action level is a reference value, which is used to determine whether the difference in irradiance output level across a UV unit is acceptable. Current methodologies for skin-testing in Ireland have been characterised and errors introduced during testing have been estimated. Action levels have been developed based on analysis of errors and requirements of skin-testing.

  6. Enhanced reactivation of ultraviolet-damaged herpes virus in ultraviolet pretreated skin fibroblasts of cancer prone donors

    SciTech Connect

    Coppey, J.; Menezes, S.

    1981-01-01

    An enhanced reactivation of ultraviolet-damaged (u.v. at 254 nm) unclear replicating double-stranded DNA viruses occurs when corresponding host cells are treated with radiation or carcinogens prior to infection. This phenomenon seems to be due to an induced DNA repair activity the nature of which is yet unknown. The u.v.-induced enhanced reactivation (ER) of u.v.-damaged herpes simplex virus (u.v. - HSV) was compared in dividing skin fibroblasts of 30 donors either normal or afflicted by genetic disorders, some of which confer a high risk for sunlight induced skin cancers. Cultures were exposed to a single dose of 1.0-25 J.m-2 from 0-60 h before infection with u.v.-HSV (at about 10-3 survival) and the rate of viral production was determined. ER was maximal for a 36 h time interval in all lines. The u.v. dose eliciting maximal ER was 15 J.m-2 in fibroblasts from normal donors, xeroderma pigmentosum (XP) heterozygotes, Mibelli's porokeratosis, diffused naevomatosis, Down's syndrome, xerodermoids, XP variants and epidermodysplasia verruciformis. However, in the latter 3 cases, ER was almost 10 times more pronounced than in the normal cases. The u.v. dose eliciting maximal ER was 0.1, 0.3 and 2 J.m-2 in excision deficient XP fibroblasts from groups A, D and C, respectively, 2.5 J.m-2 in 11961 fibroblasts and 5 J.m-2 in fibroblast lines from cockayne s syndrome.

  7. Reconstructed human epidermis for skin absorption testing: results of the German prevalidation study.

    PubMed

    Schäfer-Korting, Monika; Bock, Udo; Gamer, Armin; Haberland, Annekathrin; Haltner-Ukomadu, Eleonore; Kaca, Monika; Kamp, Hennicke; Kietzmann, Manfred; Korting, Hans Christian; Krächter, Hans-Udo; Lehr, Claus-Michael; Liebsch, Manfred; Mehling, Annette; Netzlaff, Frank; Niedorf, Frank; Rübbelke, Maria K; Schäfer, Ulrich; Schmidt, Elisabeth; Schreiber, Sylvia; Schröder, Klaus-Rudolf; Spielmann, Horst; Vuia, Alexander

    2006-06-01

    Exposure to chemicals absorbed by the skin can threaten human health. In order to standardise the predictive testing of percutaneous absorption for regulatory purposes, the OECD adopted guideline 428, which describes methods for assessing absorption by using human and animal skin. In this study, a protocol based on the OECD principles was developed and prevalidated by using reconstructed human epidermis (RHE). The permeation of the OECD standard compounds, caffeine and testosterone, through commercially available RHE models was compared to that of human epidermis and animal skin. In comparison to human epidermis, the permeation of the chemicals was overestimated when using RHE. The following ranking of the permeation coefficients for testosterone was obtained: SkinEthic > EpiDerm, EPISKIN > human epidermis, bovine udder skin, pig skin. The ranking for caffeine was: SkinEthic, EPISKIN > bovine udder skin, EpiDerm, pig skin, human epidermis. The inter-laboratory and intra-laboratory reproducibility was good. Long and variable lag times, which are a matter of concern when using human and pig skin, did not occur with RHE. Due to the successful transfer of the protocol, it is now in the validation process. PMID:16831060

  8. Resveratrol Prevents High Fluence Red Light-Emitting Diode Reactive Oxygen Species-Mediated Photoinhibition of Human Skin Fibroblast Migration

    PubMed Central

    Mamalis, Andrew; Koo, Eugene; Isseroff, R. Rivkah; Murphy, William; Jagdeo, Jared

    2015-01-01

    Background Skin fibrosis is a significant medical problem that leads to a functional, aesthetic, and psychosocial impact on quality-of-life. Light-emitting diode-generated 633-nm red light (LED-RL) is part of the visible light spectrum that is not known to cause DNA damage and is considered a safe, non-invasive, inexpensive, and portable potential alternative to ultraviolet phototherapy that may change the treatment paradigm of fibrotic skin disease. Objective The goal of our study was to investigate the how reactive oxygen species (ROS) free radicals generated by high fluence LED-RL inhibit the migration of skin fibroblasts, the main cell type involved in skin fibrosis. Fibroblast migration speed is increased in skin fibrosis, and we studied cellular migration speed of cultured human skin fibroblasts as a surrogate measure of high fluence LED-RL effect on fibroblast function. To ascertain the inhibitory role of LED-RL generated ROS on migration speed, we hypothesized that resveratrol, a potent antioxidant, could prevent the photoinhibitory effects of high fluence LED-RL on fibroblast migration speed. Methods High fluence LED-RL generated ROS were measured by flow cytometry analysis using dihydrorhodamine (DHR). For purposes of comparison, we assessed the effects of ROS generated by hydrogen peroxide (H2O2) on fibroblast migration speed and the ability of resveratrol, a well known antioxidant, to prevent LED-RL and H2O2 generated ROS-associated changes in fibroblast migration speed. To determine whether resveratrol could prevent the high fluence LED-RL ROS-mediated photoinhibition of human skin fibroblast migration, treated cells were incubated with resveratrol at concentrations of 0.0001% and 0.001% for 24 hours, irradiated with high fluences LED-RL of 480, 640, and 800 J/cm2. Results High fluence LED-RL increases intracellular fibroblast ROS and decreases fibroblast migration speed. LED-RL at 480, 640 and 800 J/cm2 increased ROS levels to 132.8%, 151.0%, and 158

  9. A tuberculin skin test survey among Ghanaian school children

    PubMed Central

    2010-01-01

    Background Ghana has not conducted a national tuberculin survey or tuberculosis prevalence survey since the establishment of the National Tuberculosis Control Programme. The primary objective of this study was therefore to determine the prevalence of tuberculin skin sensitivity in Ghanaian school children aged 6-10 years in 8 out of 10 regions of Ghana between 2004 and 2006. Methods Tuberculin survey was conducted in 179 primary schools from 21 districts in 8 regions. Schools were purposively selected so as to reflect the proportion of affluent private and free tuition public schools as well as the proportion of small and large schools. Results Of the 24,778 children registered for the survey, 23,600 (95.2%) were tested of which 21,861 (92.6%) were available for reading. The age distribution showed an increase in numbers of children towards older age: 11% of the children were 6 years and 25%, 10 years. Females were 52.5% and males 47.5%. The proportion of girls was higher in all age groups (range 51.4% to 54.0%, p < 0.001). BCG scar was visible in 89.3% of the children. The percentage of children with a BCG scar differed by district and by age. The percentage of children with a BCG scar decreased with increasing age in all districts, reflecting increasing BCG vaccination coverage in Ghana in the last ten years. The risk of tuberculosis infection was low in the northern savannah zones compared to the southern coastal zones. Using a cut-off of 15 mm, the prevalence of infection ranged from 0.0% to 5.4% and the Annual Risks of Tuberculosis Infection 0.0% to 0.6%. There was an increase in the proportion of infected children after the age of 7 years. Children attending low and middle-class schools had a higher risk of infection than children attending upper-class schools. Conclusion Tuberculosis infection is still a public health problem in Ghana and to monitor the trend, the survey needs to be repeated at 5 years interval. PMID:20102620

  10. Self-Antigen Presentation by Keratinocytes in the Inflamed Adult Skin Modulates T-Cell Auto-Reactivity.

    PubMed

    Meister, Michael; Tounsi, Amel; Gaffal, Evelyn; Bald, Tobias; Papatriantafyllou, Maria; Ludwig, Julia; Pougialis, Georg; Bestvater, Felix; Klotz, Luisa; Moldenhauer, Gerhard; Tüting, Thomas; Hämmerling, Günter J; Arnold, Bernd; Oelert, Thilo

    2015-08-01

    Keratinocytes have a pivotal role in the regulation of immune responses, but the impact of antigen presentation by these cells is still poorly understood, particularly in a situation where the antigen will be presented only in adult life. Here, we generated a transgenic mouse model in which keratinocytes exclusively present a myelin basic protein (MBP) peptide covalently linked to the major histocompatibility complex class II β-chain, solely under inflammatory conditions. In these mice, inflammation caused by epicutaneous contact sensitizer treatment resulted in keratinocyte-mediated expansion of MBP-specific CD4(+) T cells in the skin. Moreover, repeated contact sensitizer application preceding a systemic MBP immunization reduced the reactivity of the respective CD4(+) T cells and lowered the symptoms of the resulting experimental autoimmune encephalomyelitis. This downregulation was CD4(+) T-cell-mediated and dependent on the presence of the immune modulator Dickkopf-3. Thus, presentation of a neo self-antigen by keratinocytes in the inflamed, adult skin can modulate CD4(+) T-cell auto-aggression at a distal organ. PMID:25835957

  11. The use of reconstructed human epidermis for skin absorption testing: Results of the validation study.

    PubMed

    Schäfer-Korting, Monika; Bock, Udo; Diembeck, Walter; Düsing, Hans-Jürgen; Gamer, Armin; Haltner-Ukomadu, Eleonore; Hoffmann, Christine; Kaca, Monika; Kamp, Hennicke; Kersen, Silke; Kietzmann, Manfred; Korting, Hans Christian; Krächter, Hans-Udo; Lehr, Claus-Michael; Liebsch, Manfred; Mehling, Annette; Müller-Goymann, Christel; Netzlaff, Frank; Niedorf, Frank; Rübbelke, Maria K; Schäfer, Ulrich; Schmidt, Elisabeth; Schreiber, Sylvia; Spielmann, Horst; Vuia, Alexander; Weimer, Michaela

    2008-05-01

    A formal validation study was performed, in order to investigate whether the commercially-available reconstructed human epidermis (RHE) models, EPISKIN, EpiDerm and SkinEthic, are suitable for in vitro skin absorption testing. The skin types currently recommended in the OECD Test Guideline 428, namely, ex vivo human epidermis and pig skin, were used as references. Based on the promising outcome of the prevalidation study, the panel of test substances was enlarged to nine substances, covering a wider spectrum of physicochemical properties. The substances were tested under both infinite-dose and finite-dose conditions, in ten laboratories, under strictly controlled conditions. The data were subjected to independent statistical analyses. Intra-laboratory and inter-laboratory variability contributed almost equally to the total variability, which was in the same range as that in preceding studies. In general, permeation of the RHE models exceeded that of human epidermis and pig skin (the SkinEthic RHE was found to be the most permeable), yet the ranking of substance permeation through the three tested RHE models and the pig skin reflected the permeation through human epidermis. In addition, both infinite-dose and finite-dose experiments are feasible with RHE models. The RHE models did not show the expected significantly better reproducibility, as compared to excised skin, despite a tendency toward lower variability of the data. Importantly, however, the permeation data showed a sufficient correlation between all the preparations examined. Thus, the RHE models, EPISKIN, EpiDerm and SkinEthic, are appropriate alternatives to human and pig skin, for the in vitro assessment of the permeation and penetration of substances when applied as aqueous solutions. PMID:18522484

  12. Advanced tests for skin and respiratory sensitization assessment.

    PubMed

    Rovida, Costanza; Martin, Stefan F; Vivier, Manon; Weltzien, Hans Ulrich; Roggen, Erwin

    2013-01-01

    Sens-it-iv is an FP6 Integrated Project that finished in March 2011 after 66 months of activity, thanks to 12 million € of funding. The ultimate goal of the Sens-it-iv project was the development of a set of in vitro methods for the assessment of the skin and respiratory sensitization potential of chemicals and proteins. The level of development was intended to be at the point to enter the pre-validation phase. At the end of the project it can be concluded that the goal has been largely accomplished. Several advanced methods were evaluated extensively, and for some of them a detailed Standard Operating Procedure (SOP) was established. Other, less advanced methods also contributed to our understanding of the mechanisms driving sensitization. The present contribution, which has been prepared with the support of CAAT-Europe, represents a short summary of what was discussed during the 3-day end congress of the Sens-it-iv project in Brussels. It presents a list of methods that are ready for skin sensitization hazard assessment. Potency evaluation and the possibility of distinguishing skin from respiratory sensitizers are also well advanced. PMID:23665811

  13. Reactive Secondary Sequence Oxidative Pathology Polymer Model and Antioxidant Tests

    PubMed Central

    Petersen, Richard C.

    2014-01-01

    Aims To provide common Organic Chemistry/Polymer Science thermoset free-radical crosslinking Sciences for Medical understanding and also present research findings for several common vitamins/antioxidants with a new class of drugs known as free-radical inhibitors. Study Design Peroxide/Fenton transition-metal redox couples that generate free radicals were combined with unsaturated lipid oils to demonstrate thermoset-polymer chain growth by crosslinking with the α-β-unsaturated aldehyde acrolein into rubbery/adhesive solids. Further, Vitamin A and beta carotene were similarly studied for crosslink pathological potential. Also, free-radical inhibitor hydroquinone was compared for antioxidant capability with Vitamin E. Place and Duration of Study Department of Materials Science and Engineering and Department of Biomaterials, University of Alabama at Birmingham, between June 2005 and August 2012. Methodology Observations were recorded for Fenton free-radical crosslinking of unsaturated lipids and vitamin A/beta carotene by photography further with weight measurements and percent-shrinkage testing directly related to covalent crosslinking of unsaturated lipids recorded over time with different concentrations of acrolein. Also, hydroquinone and vitamin E were compared at concentrations from 0.0–7.3wt% as antioxidants for reductions in percent-shrinkage measurements, n = 5. Results Unsaturated lipid oils responded to Fenton thermoset-polymer reactive secondary sequence reactions only by acrolein with crosslinking into rubbery-type solids and different non-solid gluey products. Further, molecular oxygen crosslinking was demonstrated with lipid peroxidation and acrolein at specially identified margins. By peroxide/Fenton free-radical testing, both vitamin A and beta-carotene demonstrated possible pathology chemistry for chain-growth crosslinking. During lipid/acrolein testing over a 50 hour time period at 7.3wt% antioxidants, hydroquinone significantly reduced percent

  14. Reactivity enhancement of oxide skins in reversible Ti-doped NaAlH{sub 4}

    SciTech Connect

    Delmelle, Renaud; Borgschulte, Andreas; Gehrig, Jeffrey C.; Züttel, Andreas

    2014-12-15

    The reversibility of hydrogen sorption in complex hydrides has only been shown unambiguously for NaAlH{sub 4} doped with transition metal compounds. Despite a multitude of investigations of the effect of the added catalyst on the hydrogen sorption kinetics of NaAlH{sub 4}, the mechanism of catalysis remains elusive so far. Following the decomposition of TiCl{sub 3}-doped NaAlH{sub 4} by in-situ X-ray photoelectron spectroscopy (XPS), we link the chemical state of the dopant with those of the hydride and decomposition products. Titanium and aluminium change their oxidation states during cycling. The change of the formal oxidation state of Al from III to zero is partly due to the chemical reaction from NaAlH{sub 4} to Al. Furthermore, aluminium oxide is formed (Al{sub 2}O{sub 3}), which coexists with titanium oxide (Ti{sub 2}O{sub 3}). The interplay of metallic and oxidized Ti with the oxide skin might explain the effectiveness of Ti and similar dopants (Ce, Zr…)

  15. Skin age testing criteria: characterization of human skin structures by 500 MHz MRI multiple contrast and image processing

    NASA Astrophysics Data System (ADS)

    Sharma, Rakesh

    2010-07-01

    Ex vivo magnetic resonance microimaging (MRM) image characteristics are reported in human skin samples in different age groups. Human excised skin samples were imaged using a custom coil placed inside a 500 MHz NMR imager for high-resolution microimaging. Skin MRI images were processed for characterization of different skin structures. Contiguous cross-sectional T1-weighted 3D spin echo MRI, T2-weighted 3D spin echo MRI and proton density images were compared with skin histopathology and NMR peaks. In all skin specimens, epidermis and dermis thickening and hair follicle size were measured using MRM. Optimized parameters TE and TR and multicontrast enhancement generated better MRI visibility of different skin components. Within high MR signal regions near to the custom coil, MRI images with short echo time were comparable with digitized histological sections for skin structures of the epidermis, dermis and hair follicles in 6 (67%) of the nine specimens. Skin % tissue composition, measurement of the epidermis, dermis, sebaceous gland and hair follicle size, and skin NMR peaks were signatures of skin type. The image processing determined the dimensionality of skin tissue components and skin typing. The ex vivo MRI images and histopathology of the skin may be used to measure the skin structure and skin NMR peaks with image processing may be a tool for determining skin typing and skin composition.

  16. Contribution to the Determination of In Vivo Mechanical Characteristics of Human Skin by Indentation Test

    PubMed Central

    Zahouani, Hassan

    2013-01-01

    This paper proposes a triphasic model of intact skin in vivo based on a general phenomenological thermohydromechanical and physicochemical (THMPC) approach of heterogeneous media. The skin is seen here as a deforming stratified medium composed of four layers and made out of different fluid-saturated materials which contain also an ionic component. All the layers are treated as linear, isotropic materials described by their own behaviour law. The numerical simulations of in vivo indentation test performed on human skin are given. The numerical results correlate reasonably well with the typical observations of indented human skin. The discussion shows the versatility of this approach to obtain a better understanding on the mechanical behaviour of human skin layers separately. PMID:24324525

  17. Skin2--an in vitro human skin model: the correlation between in vivo and in vitro testing of surfactants.

    PubMed

    Demetrulias, J; Donnelly, T; Morhenn, V; Jessee, B; Hainsworth, S; Casterton, P; Bernhofer, L; Martin, K; Decker, D

    1998-02-01

    The availability of an in vitro test system to replace animal testing of potential irritants is becoming more and more urgent especially in Europe as a consequence of the European Community Cosmetics Directive. To evaluate the ability of Advanced Tissue Sciences' (ATS) ZK1301 skin model to predict the skin irritation potential of surfactants, we performed a pilot validation study utilizing four different laboratories. The in vitro protocol was designed as a quantitative pre-screen for the clinical patch studies. Sixteen substances, representing various surfactant categories and ranges of irritation potential, were tested. The 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay was used to quantitate viability in vitro. We documented the viability of tissues exposed to unknown substances for specific periods. The in vitro results were calculated as percent distilled water controls (DWC). The time required to reduce the viability of each tissue to 50% of the distilled water controls (T50) was compared to mean erythema and edema scores from the clinical studies by Pearson's correlation. The individual laboratories demonstrated coefficients of 0.72. The results indicated that the 30 min percent untreated control values best predicted the 24 h clinical patch scores. No statistically significant interlab variability was found. Only one false negative was seen when non/mild and moderate/severe irritant categories were assigned according to the in vitro scores. These results demonstrate that the skin2 in vitro test system may serve as a good screening method prior to clinical patch studies. PMID:9517918

  18. Systematic evaluation of non-animal test methods for skin sensitisation safety assessment.

    PubMed

    Reisinger, Kerstin; Hoffmann, Sebastian; Alépée, Nathalie; Ashikaga, Takao; Barroso, Joao; Elcombe, Cliff; Gellatly, Nicola; Galbiati, Valentina; Gibbs, Susan; Groux, Hervé; Hibatallah, Jalila; Keller, Donald; Kern, Petra; Klaric, Martina; Kolle, Susanne; Kuehnl, Jochen; Lambrechts, Nathalie; Lindstedt, Malin; Millet, Marion; Martinozzi-Teissier, Silvia; Natsch, Andreas; Petersohn, Dirk; Pike, Ian; Sakaguchi, Hitoshi; Schepky, Andreas; Tailhardat, Magalie; Templier, Marie; van Vliet, Erwin; Maxwell, Gavin

    2015-02-01

    The need for non-animal data to assess skin sensitisation properties of substances, especially cosmetics ingredients, has spawned the development of many in vitro methods. As it is widely believed that no single method can provide a solution, the Cosmetics Europe Skin Tolerance Task Force has defined a three-phase framework for the development of a non-animal testing strategy for skin sensitization potency prediction. The results of the first phase – systematic evaluation of 16 test methods – are presented here. This evaluation involved generation of data on a common set of ten substances in all methods and systematic collation of information including the level of standardisation, existing test data,potential for throughput, transferability and accessibility in cooperation with the test method developers.A workshop was held with the test method developers to review the outcome of this evaluation and to discuss the results. The evaluation informed the prioritisation of test methods for the next phase of the non-animal testing strategy development framework. Ultimately, the testing strategy – combined with bioavailability and skin metabolism data and exposure consideration – is envisaged to allow establishment of a data integration approach for skin sensitisation safety assessment of cosmetic ingredients. PMID:25448812

  19. Construction of Tests in the Cognitive and Psychomotor Domains for Skin and Scuba Diving.

    ERIC Educational Resources Information Center

    McCarthy, Jean

    The fundamental purposes of this study were to develop mastery tests in the cognitive and psychomotor domains for skin and scuba diving and to establish validity and reliability for the tests. A table of specifications was developed for each domain, and a pilot study refined the initial test batteries into their final form. In the main study,…

  20. Evaluation of status of tuberculin skin sensitivity test among medical students.

    PubMed

    Chander, J; Gupta, R; Subrahmanyan, S

    1997-02-01

    The status of tuberculin skin sensitivity tests was evaluated in 87 medical students. It was found that Mantoux test has less significant role to play in the vaccinated individuals and in the population at high risk of exposure. Hence this test is to be supplemented with clinical manifestations and other investigations to establish the final diagnosis of tuberculosis. PMID:9355707

  1. Bovine Tuberculosis: Effect of the Tuberculin Skin Test on In vitro Interferon gamma Responses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine tuberculosis (bTB) is a disease of zoonotic and economic importance. In many countries, control is based on test and slaughter policies and/or abattoir surveillance. For testing, cell mediated immune- (CMI-) based assays (i.e., Tuberculin skin test (TST) supplemented by the interferon gamma (...

  2. Thermographic assessment of skin prick tests in comparison with the routine evaluation methods

    PubMed Central

    Rokita, Eugeniusz; Tatoń, Grzegorz; Guzik, Tomasz; Śliwa, Tomasz

    2016-01-01

    Introduction The skin prick test is still the first and basic procedure in the diagnosis of allergic diseases. The possibility of using a sensitive thermographic method supported by the mathematical model for the assessment of skin test results will be highlighted in the studies. Aim To compare the proposed approach with routine planimetric and thermographic methods. Material and methods A mathematical model of allergic reaction was developed. Simplifying assumptions of the IgE-mediated skin reaction is the essence of the model. Investigations were performed in a group of 40 patients. Results Using the spatio-temporal evolution of temperature distributions, the ratios of the histamine released from mast cells to the control histamine were determined. The obtained values very well correlate with the standard evaluation of skin prick tests (correlation coefficient = 0.98). Conclusions The proposed method of skin test evaluation presents several advantages. The continuous acquisition of data provides the monitoring of time course of the allergic response. The transport of mediator and its concentration were distinctly discriminated, which may be diagnostically useful, especially for abnormal cases. The high sensitivity of the method enables studying patients regardless of age and skin sensitivity. PMID:27512354

  3. Humoral immunity in tuberculin skin test anergy and its role in high-risk persons exposed to active tuberculosis.

    PubMed

    Encinales, Liliana; Zuñiga, Joaquin; Granados-Montiel, Julio; Yunis, Maria; Granados, Julio; Almeciga, Ingrid; Clavijo, Olga; Awad, Carlos; Collazos, Vilma; Vargas-Rojas, María Inés; Bañales-Mendez, José Luis; Vazquez-Castañeda, Lilia; Stern, Joel N; Romero, Viviana; Fridkis-Hareli, Masha; Frindkis-Hareli, Masha; Terreros, Daniel; Fernandez-Viña, Marcelo; Yunis, Edmond J

    2010-02-01

    The most common test to identify latent tuberculosis is the tuberculin skin test that detects T cell responses of delayed type hypersensitivity type IV. Since it produces false negative reactions in active tuberculosis or in high-risk persons exposed to tuberculosis patients as shown in this report, we studied antibody profiles to explain the anergy of such responses in high-risk individuals without active infection. Our results showed that humoral immunity against tuberculin, regardless of the result of the tuberculin skin test is important for protection from active tuberculosis and that the presence of high antibody titers is a more reliable indicator of infection latency suggesting that latency can be based on the levels of antibodies together with in vitro proliferation of peripheral blood mononuclear cells in the presence of the purified protein derivative. Importantly, anti-tuberculin IgG antibody levels mediate the anergy described herein, which could also prevent reactivation of disease in high-risk individuals with high antibody titers. Such anti-tuberculin IgG antibodies were also found associated with blocking and/or stimulation of in vitro cultures of PBMC with tuberculin. In this regard, future studies need to establish if immune responses to Mycobacterium tuberculosis can generate a broad spectrum of reactions either toward Th1 responses favoring stimulation by cytokines or by antibodies and those toward diminished responses by Th2 cytokines or blocking by antibodies; possibly involving mechanisms of antibody dependent protection from Mtb by different subclasses of IgG. PMID:20004475

  4. Humoral immunity in tuberculin skin test anergy and its role in high-risk persons exposed to active tuberculosis

    PubMed Central

    Encinales, Liliana; Zuñiga, Joaquin; Yunis, Maria; Granados-Montiel, Julio; Granados, Julio; Almeciga, Ingrid; Clavijo, Olga; Awad, Carlos; Collazos, Vilma; Vargas-Rojas, María Inés; Bañales-Mendez, José Luis; Vazquez-Castañeda, Lilia; Stern, Joel N.; Romero, Viviana; Frindkis-Hareli, Masha; Terreros, Daniel; Fernandez-Viña, Marcelo; Yunis, Edmond J.

    2009-01-01

    The most common test to identify latent tuberculosis is the Tuberculin skin test that detects T cell responses of delayed type hypersensitivity type IV. Since it produces false negative reactions in active tuberculosis or in high-risk persons exposed to tuberculosis patients as shown in this report, we studied antibody profiles to explain the anergy of such responses in high-risk individuals without active infection. Our results showed that humoral immunity against Tuberculin, regardless of the result of the Tuberculin skin test is important for protection from active tuberculosis and that the presence of high antibody titers is a more reliable indicator of infection latency suggesting that latency can be based on the levels of antibodies together with in vitro proliferation of peripheral blood mononuclear cells in the presence of the purified protein derivative. Importantly, anti-Tuberculin IgG antibody levels mediate the anergy described herein, which could also prevent reactivation of disease in high-risk individuals with high antibody titers. Such IgG Tuberculin antibodies were also found associated with blocking and/or stimulation of in vitro cultures of PBMC with Tuberculin. In this regard, future studies need to establish if immune responses to Mycobacterium tuberculosis can generate a broad spectrum of reactions either toward Th1 responses favoring stimulation by cytokines or by antibodies and those toward diminished responses by Th2 cytokines or blocking by antibodies; possibly involving mechanisms of antibody dependent protection from Mtb by different subclasses of IgG. PMID:20004475

  5. The use of ex vivo human skin tissue for genotoxicity testing

    SciTech Connect

    Reus, Astrid A.; Usta, Mustafa; Krul, Cyrille A.M.

    2012-06-01

    As a result of the chemical legislation concerning the registration, evaluation, authorization and restriction of chemicals (REACH), and the Seventh Amendment to the Cosmetics Directive, which prohibits animal testing in Europe for cosmetics, alternative methods for safety evaluation of chemicals are urgently needed. Current in vitro genotoxicity assays are not sufficiently predictive for the in vivo situation, resulting in an unacceptably high number of misleading positives. For many chemicals and ingredients of personal care products the skin is the first site of contact, but there are no in vitro genotoxicity assays available in the skin for additional evaluation of positive or equivocal responses observed in regulatory in vitro genotoxicity assays. In the present study ex vivo human skin tissue obtained from surgery was used for genotoxicity evaluation of chemicals by using the comet assay. Fresh ex vivo human skin tissue was cultured in an air–liquid interface and topically exposed to 20 chemicals, including true positive, misleading positive and true negative genotoxins. Based on the results obtained in the present study, the sensitivity, specificity and accuracy of the ex vivo skin comet assay to predict in vivo genotoxicity were 89%, 90% and 89%, respectively. Donor and experimental variability were mainly reflected in the magnitude of the response and not the difference between the presence and absence of a genotoxic response. The present study indicates that human skin obtained from surgery is a promising and robust model for safety evaluation of chemicals that are in direct contact with the skin. -- Highlights: ► We use human skin obtained from surgery for genotoxicity evaluation of chemicals. ► We use the comet assay as parameter for genotoxicity in ex vivo human skin. ► Sensitivity, specificity and accuracy to predict in vivo genotoxins are determined. ► Sensitivity, specificity and accuracy are 89%, 90% and 90%, respectively. ► The method

  6. An in vitro method for detecting chemical sensitization using human reconstructed skin models and its applicability to cosmetic, pharmaceutical, and medical device safety testing.

    PubMed

    McKim, James M; Keller, Donald J; Gorski, Joel R

    2012-12-01

    Chemical sensitization is a serious condition caused by small reactive molecules and is characterized by a delayed type hypersensitivity known as allergic contact dermatitis (ACD). Contact with these molecules via dermal exposure represent a significant concern for chemical manufacturers. Recent legislation in the EU has created the need to develop non-animal alternative methods for many routine safety studies including sensitization. Although most of the alternative research has focused on pure chemicals that possess reasonable solubility properties, it is important for any successful in vitro method to have the ability to test compounds with low aqueous solubility. This is especially true for the medical device industry where device extracts must be prepared in both polar and non-polar vehicles in order to evaluate chemical sensitization. The aim of this research was to demonstrate the functionality and applicability of the human reconstituted skin models (MatTek Epiderm(®) and SkinEthic RHE) as a test system for the evaluation of chemical sensitization and its potential use for medical device testing. In addition, the development of the human 3D skin model should allow the in vitro sensitization assay to be used for finished product testing in the personal care, cosmetics, and pharmaceutical industries. This approach combines solubility, chemical reactivity, cytotoxicity, and activation of the Nrf2/ARE expression pathway to identify and categorize chemical sensitizers. Known chemical sensitizers representing extreme/strong-, moderate-, weak-, and non-sensitizing potency categories were first evaluated in the skin models at six exposure concentrations ranging from 0.1 to 2500 µM for 24 h. The expression of eight Nrf2/ARE, one AhR/XRE and two Nrf1/MRE controlled gene were measured by qRT-PCR. The fold-induction at each exposure concentration was combined with reactivity and cytotoxicity data to determine the sensitization potential. The results demonstrated that

  7. Skin microvascular reactivity in children and adolescents with type 1 diabetes in relation to levels of physical activity and aerobic fitness.

    PubMed

    Roche, Denise M; Edmunds, Sarah; Cable, Tim; Didi, Mo; Stratton, Gareth

    2008-11-01

    No studies to date have evaluated the relationship between exercise and microvascular function in youth with type 1 diabetes mellitus (T1DM). Twenty-nine complication free children and adolescents with T1DM were assessed for skin microvascular reactivity, aerobic fitness (VO2peak) and physical activity. VO2peak but not physical activity was significantly and independently associated with maximal hyperemia of the skin microcirculation (p < .01). No significant associations were found between venoarteriolar reflex (VAR) vasoconstriction and VO2peak or physical activity. Aerobic fitness may be an important indicator or mediator of effective microvascular endothelial function in youth with T1DM. PMID:19168919

  8. In vitro test of nicotine's permeability through human skin. Risk evaluation and safety aspects.

    PubMed

    Zorin, S; Kuylenstierna, F; Thulin, H

    1999-08-01

    Permeability tests with Franz' diffusion cells and an in vitro test model were made to evaluate the importance of dermal absorption of nicotine as a pathway for intoxication. Studies were carried out to ensure that safety procedures, when spilling nicotine on skin, are sufficient to prevent poisoning. Pure nicotine and nicotine in various concentrations in water or ethanol were applied on human skin or gloves in Franz' cells. Washing was simulated by removing nicotine from skin after 3 or 5 min. Permeation rate (flux) and lag time were calculated and estimated for human skin. Different glove materials were tested for their nicotine breakthrough time. Flux depended on concentration in a non-linear way when nicotine-water solutions were tested. Highest flux was found in 50% w/w nicotine dissolved in water. Solutions with low concentration of nicotine (1% w/w) dissolved in water had a similar permeation rate to 100% nicotine. Flux was found to be low when using ethanol as a vehicle; flux was also pH-dependent. The nicotine-water solution containing acetic acid had the lowest flux. The tests where nicotine was washed away revealed that skin served as a possible nicotine depot, because nicotine concentration in the receptor compartment continued to increase after removing the nicotine from the surface. The length of contact time affected the amount of substance passing the skin, resulting in great difference between 3 and 5 min contact time, 5 min giving higher nicotine concentration and 3 min lower. This emphasizes the importance of washing away nicotine spilled on skin rapidly. Two glove types were tested and they were found to be appropriate in their use with nicotine if changed regularly. PMID:10518466

  9. Controlling tuberculosis in a llama (Lama glama) herd using clinical signs, tuberculin skin testing and serology.

    PubMed

    Twomey, D F; Collins, R; Cranwell, M P; Crawshaw, T R; Higgins, R J; Dean, G S; Vordermeier, H M; Hollingdale, A; de la Rua-Domenech, R

    2012-05-01

    An outbreak of tuberculosis (TB), caused by Mycobacterium bovis, was investigated in a small herd of llamas (Lama glama). Based on three ante-mortem diagnostic methods (clinical signs, tuberculin skin test reactions, and 'Rapid Test' serology), 12 llamas were selected for examination post-mortem. Grossly visible lesions suspicious of TB were observed in eight animals, four of which had exhibited clinical signs, one was a skin test 'reactor', and three had been seropositive. M. bovis was isolated from seven of these eight animals. Clinical signs combined with serology were found to be useful in identifying infected animals, but tuberculin skin testing had limited negative predictive value as four llamas that were subsequently confirmed as infected were not detected using this assay. PMID:21704542

  10. Tuberculin skin testing in US Navy and Marine Corps personnel and recruits, 1980-86.

    PubMed Central

    Cross, E R; Hyams, K C

    1990-01-01

    An extensive skin testing program is part of the United States Naval Medical Command's infectious disease control effort. From 1980 to 1986, 2,306,533 skin tests, using five TU PPD, were performed on active-duty Navy and Marine Corps personnel, 0.97 percent of which were positive. A downward trend in positive tests was found with a high of 1.43 percent in 1980 and a low of 0.80 percent in 1983. Since 1984, the percentage of positive tests has remained the same or increased. Shore-based medical facilities around the world reported 1,491,646 skin tests with 1.07 percent positive; Navy ships reported 814,887 skin tests with 0.78 percent positive. PPD-positivity for ships in the Pacific area was higher (0.98 percent) than for ships in the Atlantic (0.62 percent). During this same period, the percentage of positive tests in Navy and Marine Corps recruits ranged from a high of 1.82 percent in 1981 to a low of 1.23 percent in 1986. Since 1984, the percentage of positive tests has remained relatively stable in recruits. The frequency of positive PPD tests found in this study is lower than the percentage positive (1.59 percent) found in active-duty Navy personnel in 1969 and the percentage positive (5.2 percent) found in a study of Navy and Marine Corps recruits between 1958 and 1969. PMID:2316764

  11. The use of ex vivo human skin tissue for genotoxicity testing.

    PubMed

    Reus, Astrid A; Usta, Mustafa; Krul, Cyrille A M

    2012-06-01

    As a result of the chemical legislation concerning the registration, evaluation, authorization and restriction of chemicals (REACH), and the Seventh Amendment to the Cosmetics Directive, which prohibits animal testing in Europe for cosmetics, alternative methods for safety evaluation of chemicals are urgently needed. Current in vitro genotoxicity assays are not sufficiently predictive for the in vivo situation, resulting in an unacceptably high number of misleading positives. For many chemicals and ingredients of personal care products the skin is the first site of contact, but there are no in vitro genotoxicity assays available in the skin for additional evaluation of positive or equivocal responses observed in regulatory in vitro genotoxicity assays. In the present study ex vivo human skin tissue obtained from surgery was used for genotoxicity evaluation of chemicals by using the comet assay. Fresh ex vivo human skin tissue was cultured in an air-liquid interface and topically exposed to 20 chemicals, including true positive, misleading positive and true negative genotoxins. Based on the results obtained in the present study, the sensitivity, specificity and accuracy of the ex vivo skin comet assay to predict in vivo genotoxicity were 89%, 90% and 89%, respectively. Donor and experimental variability were mainly reflected in the magnitude of the response and not the difference between the presence and absence of a genotoxic response. The present study indicates that human skin obtained from surgery is a promising and robust model for safety evaluation of chemicals that are in direct contact with the skin. PMID:22507867

  12. Early skin testing is effective for diagnosis of hypersensitivity reactions occurring during anesthesia.

    PubMed

    Lafuente, A; Javaloyes, G; Berroa, F; Goikoetxea, M J; Moncada, R; Núñez-Córdoba, J M; Cabrera-Freitag, P; D'Amelio, C; Sanz, M L; Gastaminza, G

    2013-06-01

    Allergic skin tests have to be performed 4-6 weeks after an allergic anesthetic reaction. Patients with allergic reactions during anesthesia were prospectively included (n = 44). Skin tests were performed in two stages: (i) Stage 1 (S1), 0-4 days after the reaction; and (ii) Stage 2 (S2), 4-8 weeks after. Five (11.5%) surgical procedures were suspended due to the reaction. Positive skin tests were obtained in 25/44 patients (57%). Allergic diagnosis was carried out at S1 in 15/25 (60%) and at S2 in 10/25 (40%). Three patients resulted positive only in S1. Overall agreement among S1 and S2 skin tests was 70.45%. The kappa statistic was 0.41 (P-value = 0.002). Odds ratio of obtaining a false negative in S1 (compared with S2) was 3.33. Early allergological study is useful, could minimize false negatives, but should be considered as a complement to late skin tests. PMID:23646901

  13. Cosmetics Europe multi-laboratory pre-validation of the SkinEthic™ reconstituted human corneal epithelium test method for the prediction of eye irritation.

    PubMed

    Alépée, N; Bessou-Touya, S; Cotovio, J; de Smedt, A; de Wever, B; Faller, C; Jones, P; Le Varlet, B; Marrec-Fairley, M; Pfannenbecker, U; Tailhardat, M; van Goethem, F; McNamee, P

    2013-08-01

    Cosmetics Europe, The Personal Care Association, known as Colipa before 2012, conducted a program of technology transfer and assessment of Within/Between Laboratory (WLV/BLV) reproducibility of the SkinEthic™ Reconstituted Human Corneal Epithelium (HCE) as one of two human reconstructed tissue eye irritation test methods. The SkinEthic™ HCE test method involves two exposure time treatment procedures - one for short time exposure (10 min - SE) and the other for long time exposure (60 min - LE) of tissues to test substance. This paper describes pre-validation studies of the SkinEthic™ HCE test method (SE and LE protocols) as well as the Eye Peptide Reactivity Assay (EPRA). In the SE WLV study, 30 substances were evaluated. A consistent outcome with respect to viability measurement across all runs was observed with all substances showing an SD of less than 18%. In the LE WLV study, 44 out of 45 substances were consistently classified. These data demonstrated a high level of reproducibility within laboratory for both the SE and LE treatment procedures. For the LE BLV, 19 out of 20 substances were consistently classified between the three laboratories, again demonstrating a high level of reproducibility between laboratories. The results for EPRA WLV and BLV studies demonstrated that all substances analysed were categorised similarly and that the method is reproducible. The SkinEthic™ HCE test method entered into the experimental phase of a formal ECVAM validation program in 2010. PMID:23524228

  14. Utility testing of an apple skin color MdMYB1 marker in two progenies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A reported allele-specific dCAP PCR marker associated with apple fruit red skin color was tested in 18 elite breeding parents and two apple cross populations. Among all tested cultivars except one, a consistent relationship was observed between red fruit color and the presence of allele. In both pop...

  15. Cigarette Smoking and Skin Prick Test in Patients With Allergic Rhinitis

    PubMed Central

    Khazaei, Hossein Ali; Khazaei, Bahman; Dashtizadeh, Gholam Ali; Mohammadi, Mahdi

    2015-01-01

    Background: Allergic Rhinitis (AR) is the most common allergic disease, affecting 30% of population around the world. The disease is predominantly associated with exposure to some aeroallergens like cigarette smoking. Skin Prick Test (SPT) is a method of detecting immediate allergic reactions and is applied for controlling disease and therapeutic modality. Objectives: This study was designed to investigate the effect of cigarette smoking on SPT results among male and female individuals with AR disease. Patients and Methods: A total of 478 patients with AR admitted to the 2 main hospitals of Zahedan City from 2005 to 2012, were recruited in this analytic-descriptive study. Categories of smokers and never smokers were used based on patient’s statements and their history of smoking. SPT was performed with panel of some allergens and results were recorded and analyzed statistically. Odds ratio and confidence interval method were calculated using univariate logistic regression. Results: The results of this study indicated that 41.4% of patients with allergic rhinitis was smoker with ages ranged from 15 to 70 years. The result of this study also showed that smoking has no effect on SPT results of pollen and weeds aeroallergens conducted on male and female AR patients. However, male were significantly more sensitive than female in terms of sensitivity to the aspergillus, cladosporium, house dust mite, grasses, wheat, cockroach, and feather allergens. Conclusions: Our findings did not support the effect of cigarette smoking on SPT reactivity to pollen and weeds aeroallergens. However, male were significantly more sensitive than female in terms of sensitivity to some allergens. PMID:26495257

  16. Reactive and Reciprocal Inhibition Therapies in the Group Treatment of Test Anxiety.

    ERIC Educational Resources Information Center

    Kearney, Maureen

    This experiment compares the effects of group reactive inhibition therapy and group reciprocal inhibition therapy with no treatment on the anxiety level of test-anxious college students. Twenty undergraduate students volunteered for the study and were assigned to either the reactive inhibition group, the reciprocal inhibition group, or the…

  17. Reactivity of Hontomín carbonate rocks to acidic solution injection: reactive "push-pull" tracer tests results

    NASA Astrophysics Data System (ADS)

    De Gaspari, Francesca; Cabeza, Yoar; Luquot, Linda; Rötting, Tobias; Saaltink, Maarten W.; Carrera, Jesus

    2014-05-01

    Several field tests will be carried out in order to characterize the reservoir for CO2 injection in Hontomín (Burgos, Spain) as part of the Compostilla project of "Fundación Ciudad de la Energía" (CIUDEN). Once injected, the dissolution of the CO2 in the resident brine will increase the acidity of the water and lead to the dissolution of the rocks, constituted mainly by carbonates. This mechanism will cause changes in the aquifer properties such as porosity and permeability. To reproduce the effect of the CO2 injection, a reactive solution with 2% of acetic acid is going to be injected in the reservoir and extracted from the same well (reactive "push-pull" tracer tests) to identify and quantify the geochemical reactions occurring into the aquifer. The reactivity of the rock will allow us also to evaluate the changes of its properties. Previously, theoretical calculations of Damkhöler numbers were done to determine the acid concentrations and injection flow rates needed to generate ramified-wormholes patterns, during theses "push-pull" experiments. The aim of this work is to present the results and a preliminary interpretation of the field tests.

  18. Skin prick test results to artesunate in children sensitized to Artemisia vulgaris L.

    PubMed

    Mori, F; Pantano, S; Rossi, M E; Montagnani, C; Chiappini, E; Novembre, E; Galli, L; de Martino, M

    2015-09-01

    Artemisia vulgaris L and Artemisia annua L (Chinese: qinghao) are similar plants of the Asterbaceae family. Artesunate, a semi-synthetic derivate of artemisin which is the active principle extract of the plant qinghao, has antimalarial properties. Some cases of severe allergic reactions to artesunate have been described. The purpose of this study was to evaluate the association between positive skin tests to Artemisia vulgaris L allergen and a preparation of injectable artesunate. A total of 531 children were skin prick tested with inhalants (including Artemisia vulgaris L), foods, and artesunate. Among the 59 patients positive to Artemisia vulgaris L only one child was also positive to artesunate. No child was positive to artesunate in those negative to Artemisia vulgaris L. We conclude that Artemisia vulgaris L sensitization is not associated with sensitization to artesunate; consequently, skin test to artesunate should not be carried out before using the drug considering the rare allergic reactions. PMID:26157064

  19. Pulse testing in the presence of wellbore storage and skin effects

    SciTech Connect

    Ogbe, D.O.; Brigham, W.E.

    1984-08-01

    A pulse test is conducted by creating a series of short-time pressure transients in an active (pulsing) well and recording the observed pressure response at an observation (responding) well. Using the pressure response and flow rate data, the transmissivity and storativity of the tested formation can be determined. Like any other pressure transient data, the pulse-test response is significantly influenced by wellbore storage and skin effects. The purpose of this research is to examine the influence of wellbore storage and skin effects on interference testing in general and on pulse-testing in particular, and to present the type curves and procedures for designing and analyzing pulse-test data when wellbore storage and skin effects are active at either the responding well or the pulsing well. A mathematical model for interference testing was developed by solving the diffusivity equation for radial flow of a single-phase, slightly compressible fluid in an infinitely large, homogeneous reservoir. When wellbore storage and skin effects are present in a pulse test, the observed response amplitude is attenuated and the time lag is inflated. Consequently, neglecting wellbore storage and skin effects in a pulse test causes the calculated storativity to be over-estimated and the transmissivity to be under-estimated. The error can be as high as 30%. New correlations and procedures are developed for correcting the pulse response amplitude and time lag for wellbore storage effects. Using these correlations, it is possible to correct the wellbore storage-dominated response amplitude and time lag to within 3% of their expected values without wellbore storage, and in turn to calculate the corresponding transmissivity and storativity. Worked examples are presented to illustrate how to use the new correction techniques. 45 references.

  20. Testing of explosives mixed with clay to determine maximum explosive content of non-reactive mixtures

    SciTech Connect

    Garza, R; Green, L; Maienschein, J; Pruneda, C

    1998-07-21

    This report contains a detailed description of the experiments conducted to demonstrate that debris from explosives testing in a shot tank that contains 4 weight percent or less of explosive is non-reactive under the specified testing protocol in the Code of Federal Regulations. As such it is a companion report to UCRL-ID-128999, "Program for Certification of Waste from Contained Firing Facility - Establishment of Waste as Non-Reactive and Discussion of Potential Waste Generation Problems."

  1. A skin test survey of valley fever in Tijuana, Mexico.

    PubMed

    Fredrich, B E

    1989-01-01

    Results of a study of the prevalence of valley fever among 1128 residents of Tijuana, Baja California are presented. Children from primary and middle schools (n = 497) and adults from technical institutes and maquiladoras (assembly plants) were tested for reaction to both spherulin and coccidioidin during 1985-1986, and they completed a questionnaire containing 23 variables on their socio-environment. Place of residence was mapped. The population sampled is largely middle class. Discriminant analysis indicates the distribution of positive cases is not clustered, nor can it be correlated with geomorphic factors such as mesa tops, canyons, or valley bottoms. PMID:2588049

  2. The autologous serum skin test: a screening test for autoantibodies in chronic idiopathic urticaria.

    PubMed

    Sabroe, R A; Grattan, C E; Francis, D M; Barr, R M; Kobza Black, A; Greaves, M W

    1999-03-01

    One-third of patients with chronic idiopathic urticaria (CIU) have circulating functional autoantibodies against the high affinity IgE receptor FcepsilonRI, or IgE. The intradermal injection of autologous serum causes a weal and flare reaction in many patients with CIU, and this reaction forms the basis of the autologous serum skin test (ASST). We have determined the parameters of the ASST which define the optimal sensitivity and specificity for the identification of patients with autoantibodies. Two physicians (R.A. S. and C.E.H.G.) performed ASSTs in a total of 155 patients with CIU, 40 healthy control subjects, 15 patients with dermographism, nine with cholinergic urticaria and 10 with atopic eczema. Patients were classified as having functional autoantibodies by demonstrating in vitro serum-evoked histamine release from the basophils of two healthy donors. There were significant differences (P < 0.001) in the mean weal diameter, weal volume, weal redness and flare area of the intradermal serum-induced cutaneous responses at 30 min between patients with CIU with autoantibodies and either those without autoantibodies or control subjects. The optimum combined sensitivity and specificity of the ASST was obtained if a positive test was defined as a red serum-induced weal with a diameter of >/= 1.5 mm than the saline-induced response at 30 min. For R.A.S. and C.E.H.G., the ASST sensitivity was 65% and 71% and specificity was 81% and 78%, respectively. Using these criteria, the following subjects had positive ASSTs: none of 15 dermographics, none of 10 atopics, one of nine cholinergics and one of 40 controls. PMID:10233264

  3. Carotenoid intake does not mediate a relationship between reactive oxygen species and bright colouration: experimental test in a lizard.

    PubMed

    Olsson, Mats; Wilson, Mark; Isaksson, Caroline; Uller, Tobias; Mott, Beth

    2008-04-01

    We performed experiments on male Australian painted dragon lizards (Ctenophorus pictus) to test the hypothesis that carotenoids can scavenge reactive oxygen species (ROS), protecting the organism from oxidative stress, and that this capacity is reflected in skin colours involved in signalling. Subsequent to 4 weeks of carotenoid treatment we used flow cytometry to analyse unspecified ROS (H(2)O(2), singlet oxygen, superoxide and peroxynitrite level), hereafter termed ROS, and baseline superoxide specifically (bSO in peripheral blood cells). Mean background levels of ROS and bSO did not differ between carotenoid-treated and control males. bSO, which represents the superoxide level in un-manipulated blood, was negatively correlated with colour development in all males, regardless of carotenoid treatment. Thus, carotenoid intake does not reduce circulating levels of ROS or bSO, suggesting that carotenoids are inefficient antioxidants in vivo and, therefore, are unlikely to provide a direct link between oxidative stress and colouration. PMID:18375850

  4. Unsaturated fatty acids show clear elicitation responses in a modified local lymph node assay with an elicitation phase, and test positive in the direct peptide reactivity assay.

    PubMed

    Yamashita, Kunihiko; Shinoda, Shinsuke; Hagiwara, Saori; Miyazaki, Hiroshi; Itagaki, Hiroshi

    2015-12-01

    The Organisation for Economic Co-operation and Development (OECD) Test Guidelines (TG) adopted the murine local lymph node assay (LLNA) and guinea pig maximization test (GPMT) as stand-alone skin sensitization test methods. However, unsaturated carbon-carbon double-bond and/or lipid acids afforded false-positive results more frequently in the LLNA compared to those in the GPMT and/or in human subjects. In the current study, oleic, linoleic, linolenic, undecylenic, fumaric, maleic, and succinic acid and squalene were tested in a modified LLNA with an elicitation phase (LLNA:DAE), and in a direct peptide reactivity assay (DPRA) to evaluate their skin-sensitizing potential. Oleic, linoleic, linolenic, undecylenic and maleic acid were positive in the LLNA:DAE, of which three, linoleic, linolenic, and maleic acid were positive in the DPRA. Furthermore, the results of the cross-sensitizing tests using four LLNA:DAE-positive chemicals were negative, indicating a chemical-specific elicitation response. In a previous report, the estimated concentration needed to produce a stimulation index of 3 (EC3) of linolenic acid, squalene, and maleic acid in the LLNA was < 10%. Therefore, these chemicals were classified as moderate skin sensitizers in the LLNA. However, the skin-sensitizing potential of all LLNA:DAE-positive chemicals was estimated as weak. These results suggested that oleic, linoleic, linolenic, undecylenic, and maleic acid had skin-sensitizing potential, and that the LLNA overestimated the skin-sensitizing potential compared to that estimated by the LLNA:DAE. PMID:26558466

  5. Flaxseed (Linum usitatissimum) supplementation associated with reduced skin test lesional area in horses with Culicoides hypersensitivity

    PubMed Central

    O'Neill, Wendy; McKee, Sharyn; Clarke, Andrew F.

    2002-01-01

    Abstract The purpose of this study was to quantify the effect of flaxseed (Linum usitatissimum) supplementation on the skin test response of atopic horses. Six horses that displayed a positive skin test for allergy to extract from Culicoides sp. participated in the 42-day, placebo-controlled, double-blind, cross-over trial. Results showed that supplementation with flaxseed for 42 days in our experimental horses reduced the mean skin test response to Culicoides sp. This observation was concurrent with a significant decrease in the long-chain saturated fatty acids; behenic acid (22:0) and lignoceric acid (24:0), in the hair of horses receiving flaxseed. There was also a significant decrease in aspartate aminotransferase, and increase in serum glucose in the treatment animals at specific sampling points. It was concluded that; in this small pilot study, flaxseed was able to reduce the lesional area of the skin test response of atopic horses, alter the fatty acid profile of the hair, reduce inflammation, and did not elicit any negative side-effects in the experimental horses. PMID:12418783

  6. Anaphylaxis to Spirulina confirmed by skin prick test with ingredients of Spirulina tablets.

    PubMed

    Le, Thuy-My; Knulst, André C; Röckmann, Heike

    2014-12-01

    Spirulina (Arthrospira platensis), blue-green microalgae, has high content in proteins, γ-linoleic acid and vitamins and therefore gained popularity as food supplement. According to the Food and Agriculture Organization of the United Nations Spirulina is also an interesting alternative and sustainable protein source with the growing world population. We present a case of a 17-year-old male, who developed anaphylaxis the first time he ingested a Spirulina tablet. Skin prick test with diluted Spirulina tablet was positive. Further skin prick testing with separated ingredients (Spirulina platensis algae, silicon dioxide, inulin and magnesium stearate) was only positive for Spirulina platensis algae and negative in controls, confirming the allergy was caused by Spirulina and not by one of the additives. This case report shows that diagnosis of Spirulina allergy can safely be made by skin prick test with dilutions of the A. platensis or even more simple by skin prick test with the diluted tablet. Since Spirulina has gained popularity as food and nutritional supplement, it is important to realize the potential risk of this dietary supplement. Before Spirulina is produced and consumed on a wider scale, allergenicity risk assessment should be performed, including investigation of potential crossreactivity with well-known inhalant allergens and foods. PMID:25445756

  7. Analysis of skin patch test results and metalloproteinase-2 levels in a patient with contact dermatitis

    PubMed Central

    Czajkowski, Rafał; Kowaliszyn, Bogna; Żbikowska-Gotz, Magdalena; Bartuzi, Zbigniew

    2015-01-01

    Introduction The complex course of skin reactions that contact eczema involves is due in part to abnormalities of the extracellular matrix function. Proteins that degrade extracellular matrix components include metalloproteinases (MMP), which are divided into subcategories depending on the chemical structure and substrate specificity. Aim To analyse patch test results in contact dermatitis patients and to assess MMP-2 levels during skin lesion exacerbation and remission. Material and methods Fifty patients suffering from contact eczema were qualified to the study and 20 healthy volunteers as a control group. The study group patients had epidermal skin tests performed with the “European Standard” set. To assess the MMP-2 level in serum, venous blood was drawn, twice from study group patients – during contact dermatitis exacerbation and remission periods – and once from control group patients. Assessment of MMP-2 in serum was done with ELISA immunoassay. To verify the proposed hypotheses, parametric and nonparametric significance tests were used. Results Hands were the most frequent location of contact dermatitis. Nickel (II) sulphate was the most frequent sensitizing substance. Mean MMP-2 levels were statistically higher in the study group both in contact dermatitis exacerbation and remission periods than in the control group. There was no statistically significant difference between MMP-2 levels and skin patch test results. Conclusions Nickel is one of the most allergenic contact allergens in patients with contact dermatitis. Metalloproteinase-2 is a good marker of contact dermatitis in various stages of the disease. PMID:26161054

  8. Biaxial tensile tests identify epidermis and hypodermis as the main structural elements of sweet cherry skin

    PubMed Central

    Brüggenwirth, Martin; Fricke, Heiko; Knoche, Moritz

    2014-01-01

    The skin of developing soft and fleshy fruit is subjected to considerable growth stress, and failure of the skin is associated with impaired barrier properties in water transport and pathogen defence. The objectives were to establish a standardized, biaxial tensile test of the skin of soft and fleshy fruit and to use it to characterize and quantify mechanical properties of the sweet cherry (Prunus avium) fruit skin as a model. A segment of the exocarp (ES) comprising cuticle, epidermis, hypodermis and adhering flesh was mounted in the elastometer such that the in vivo strain was maintained. The ES was pressurized from the inner surface and the pressure and extent of associated bulging were recorded. Pressure : strain responses were almost linear up to the point of fracture, indicating that the modulus of elasticity was nearly constant. Abrading the cuticle decreased the fracture strain but had no effect on the fracture pressure. When pressure was held constant, bulging of the ES continued to increase. Strain relaxation upon releasing the pressure was complete and depended on time. Strains in longitudinal and latitudinal directions on the bulging ES did not differ significantly. Exocarp segments that released their in vivo strain before the test had higher fracture strains and lower moduli of elasticity. The results demonstrate that the cherry skin is isotropic in the tangential plane and exhibits elastic and viscoelastic behaviour. The epidermis and hypodermis, but not the cuticle, represent the structural ‘backbone’ in a cherry skin. This test is useful in quantifying the mechanical properties of soft and fleshy fruit of a range of species under standardized conditions. PMID:24876301

  9. Biaxial tensile tests identify epidermis and hypodermis as the main structural elements of sweet cherry skin.

    PubMed

    Brüggenwirth, Martin; Fricke, Heiko; Knoche, Moritz

    2014-01-01

    The skin of developing soft and fleshy fruit is subjected to considerable growth stress, and failure of the skin is associated with impaired barrier properties in water transport and pathogen defence. The objectives were to establish a standardized, biaxial tensile test of the skin of soft and fleshy fruit and to use it to characterize and quantify mechanical properties of the sweet cherry (Prunus avium) fruit skin as a model. A segment of the exocarp (ES) comprising cuticle, epidermis, hypodermis and adhering flesh was mounted in the elastometer such that the in vivo strain was maintained. The ES was pressurized from the inner surface and the pressure and extent of associated bulging were recorded. Pressure : strain responses were almost linear up to the point of fracture, indicating that the modulus of elasticity was nearly constant. Abrading the cuticle decreased the fracture strain but had no effect on the fracture pressure. When pressure was held constant, bulging of the ES continued to increase. Strain relaxation upon releasing the pressure was complete and depended on time. Strains in longitudinal and latitudinal directions on the bulging ES did not differ significantly. Exocarp segments that released their in vivo strain before the test had higher fracture strains and lower moduli of elasticity. The results demonstrate that the cherry skin is isotropic in the tangential plane and exhibits elastic and viscoelastic behaviour. The epidermis and hypodermis, but not the cuticle, represent the structural 'backbone' in a cherry skin. This test is useful in quantifying the mechanical properties of soft and fleshy fruit of a range of species under standardized conditions. PMID:24876301

  10. DESIGN AND DEVELOPMENT OF A HAZARDOUS WASTE REACTIVITY TESTING PROTOCOL

    EPA Science Inventory

    A test protocol to determine the gross chemical composition of waste materials has been developed for use at uncontrolled hazardous waste sites. Included is a field test kit, flow diagrams, a descriptive manual and a mixing device to observe the effects of mixing two hazardous wa...

  11. Photopatch test reactivity: effect of photoallergen concentration and UVA dosaging.

    PubMed

    Hasan, T; Jansen, C T

    1996-06-01

    We have studied the influence of variations in allergen concentration and UVA dosaging on the results of photopatch testing with the Scandinavian standard photopatch series in 29 patients with photocontact and/or contact allergy to 1 or several of the allergens in that series. Photocontact test reactions were more sensitive to allergen dilution than plain contact test reactions. Even dilution from the standard 5% to 2.5% significantly reduced para-aminobenzoic acid photocontact test reactions. Reducing the UVA dose from the standard 5 J/cm2 to 2.5 or 1 J/cm2 in 2 out of 5 cases turned a significant (++) reaction into a doubtful one (+). Increasing the standard UVA dose of 5 J/ cm2 to 20-40 J/cm2 turned a single + photocontact reaction to trichlorcarbanilide and a single 1 + plain contact reaction to chlorhexidine into ++ reactions. In the majority of cases, however, neither photocontact nor plain contact test reactions were augemented by UVA doses up to 80 J/cm2. We conclude that a UVA dose of 5 J/cm2 is sufficient for eliciting photocontact allergic test reactions, and that a reduction of either the UVA dose level or the standard allergen concentrations of the Scandinavian photopatch test guidelines may cause loss of significant photocontact test reactions in a proportion of the cases. PMID:8879921

  12. The importance of awareness for veterinarians involved in cattle tuberculosis skin testing.

    PubMed

    Humblet, M-F; Moyen, J-L; Bardoux, P; Boschiroli, M L; Saegerman, C

    2011-12-01

    France is currently facing a re-emergence of bovine tuberculosis in several regions. To assess the knowledge of veterinary field practitioners concerning skin testing, a questionnaire-based methodology developed in Belgium was adapted to the context of the French department of Dordogne. The veterinarians involved in herds skin testing were solicited to participate to the survey (n = 94), through an anonymous postal questionnaire including items related to each step of the skin test procedure. Each item of the questionnaire was allotted a compliance score by 5 experts in the field of bovine tuberculosis (0, 1 or 2 a correct, acceptable and unacceptable answer, respectively). These scores were balanced over 30 criteria according to their potential impact on the non-detection of reactors, on the basis of 11 experts' opinion. A global score was calculated for each participating veterinarian. In addition, the Departmental sanitary authorities held meetings in December 2005 and June 2006 to make the veterinarians aware of the importance of correctly performing the skin test. The participants to the study were asked to fill in the questionnaire in duplicate: one related to their practices before the meeting, and the other one focusing on their practices after the meeting. A comparison of both situations was carried out (pre- and post-awareness meeting), as well as a comparison with the Belgian situation, arbitrarily selected as reference for the methodology. The participation was representative and reached a 23.4% rate. A significant difference was noticed between the mean global score reached before and after the meeting. These results show the usefulness of an appropriate awareness campaign of veterinarians in relation to skin testing and the importance of frequently holding awareness meetings in areas remaining confronted with bovine tuberculosis problems. It also highlights the interest of a structured auto-assessment process of veterinary practices. PMID:21569223

  13. 75 FR 47592 - Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-06

    ..., 2007 (72 FR 32647) (FRL-8135-9), of national experts in which the revisions made in June 2006, were... AGENCY Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other... Product Performance of Skin-applied Insect Repellents of Insect and Other Arthropods Test...

  14. Skin Complications

    MedlinePlus

    ... drugs that can help clear up this condition. Day-to-Day Skin Care See our tips for daily skin ... Risk? Diagnosis Lower Your Risk Risk Test Alert Day Prediabetes My Health Advisor Tools to Know Your ...

  15. The use of Reactive Ion Etching for obtaining “free” silica nano test tubes

    NASA Astrophysics Data System (ADS)

    Buyukserin, Fatih; Martin, Charles R.

    2010-10-01

    Silica nano test tubes are one-dimensional inorganic nanostructures with several biotechnological applications including biosensing, magnetic resonance imaging, and targeted cancer therapeutics. They are generally prepared by sol-gel deposition of silica to nanoporous alumina templates. Preparing samples composed of isolated free silica nano test tubes can be a challenging process due to the conformal coating of silica on the template. This causes the formation of a top-surface silica layer which laterally connects the nano test tubes. Herein, we detailed the use of Reactive Ion Etching to remove this top-surface silica layer which yields free silica nano test tubes with template dissolution. Compared with the mechanical polishing approach, Reactive Ion Etching treatment allows a fine manipulation ability of the surface material at the nanoscale level. When used excessively, Reactive Ion Etching causes an orifice closing phenomenon that may be employed to create novel one-dimensional nanocapsules.

  16. American cutaneous leishmaniasis: use of a skin test as a predictor of relapse after treatment.

    PubMed Central

    Passos, V. M.; Barreto, S. M.; Romanha, A. J.; Krettli, A. U.; Volpini, A. C.; Lima e Costa, M. F.

    2000-01-01

    While relapses following clinical cure of American cutaneous leishmaniasis are frequent, no test has been described until now to predict such relapses. A cohort of 318 American cutaneous leishmaniasis patients was followed up for two years after treatment with meglumine antimoniate, during which time 32 relapses occurred, 30 in the first year and two in the second (accumulated risk: 10.5%). No association was found between these relapses and the parasite-specific antibody response before and after treatment, or between the relapses and stratification by sociodemographic and clinical characteristics. However when Leishmania was used as antigen, patients with a negative skin test at the time of diagnosis presented a 3.4-fold higher risk (hazard risk = 3.4; 95% confidence interval, 1.7-7.0) of American cutaneous leishmaniasis relapse, compared with patients with a positive response. This result shows that the skin test can be a predictor of American cutaneous leishmaniasis relapse after treatment. PMID:10994280

  17. Testing and Analysis of Composite Skin/Stringer Debonding Under Multi-Axial Loading

    NASA Technical Reports Server (NTRS)

    Krueger, Ronald; Cvitkovich, Michael K.; O'Brien, T. Kevin; Minguet, Pierre J.

    2000-01-01

    A consistent step-wise approach is presented to investigate the damage mechanism in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out-of-plane) loading conditions. The approach uses experiments to detect the failure mechanism, computational stress analysis to determine the location of first matrix cracking and computational fracture mechanics to investigate the potential for delamination growth. In a first step, tests were performed on specimens, which consisted of a tapered composite flange, representing a stringer or frame, bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending to evaluate the debonding mechanisms between the skin and the bonded stringer. For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both in-plane tension and out-of-plane bending loads simultaneously. Specimen edges were examined on the microscope to document the damage occurrence and to identify typical damage patterns. For all three load cases, observed failure initiated in the flange, near the flange tip, causing the flange to almost fully debond from skin. In a second step, a two dimensional plane-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, computed principal stresses exceeded the transverse strength of the material in those areas of the flange where the matrix cracks had developed during the tests. In a third step, delaminations of various lengths were simulated in two locations where delaminations were observed during the tests. The analyses showed that at the loads corresponding to matrix ply crack initiation computed strain energy release rates exceeded the values obtained from a mixed mode failure criterion in one location, Hence. Unstable delamination propagation is likely to occur as

  18. Testing and Analysis of Composite Skin/Stringer Debonding under Multi-Axial Loading

    NASA Technical Reports Server (NTRS)

    Krueger, Ronald; Cvitkovich, Michael; OBrien, Kevin; Minguet, Pierre J.

    2000-01-01

    A consistent step-wise approach is presented to investigate the damage mechanism in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out-of-plane) loading conditions. The approach uses experiments to detect the failure mechanism, computational stress analysis to determine the location of first matrix cracking and computational fracture mechanics to investigate the potential for delamination growth. In a first step, tests were performed on specimens, which consisted of a tapered composite flange, representing a stringer or frame, bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending to evaluate the debonding mechanisms between the skin and the bonded stringer. For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both in-plane tension and out-of-plane bending loads simultaneously. Specimen edges were examined on the microscope to document the damage occurrence and to identify typical damage patterns. For all three load cases, observed failure initiated in the flange, near the flange tip, causing the flange to almost fully debond from the skin. In a second step, a two-dimensional plane-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, computed principal stresses exceeded the transverse strength of the material in those areas of the flange where the matrix cracks had developed during the tests. In a third step, delaminations of various lengths were simulated in two locations where delaminations were observed during the tests. The analyses showed that at the loads corresponding to matrix ply crack initiation computed strain energy release rates exceeded the values obtained from a mixed mode failure criterion in one location. Hence, unstable delamination propagation is likely to occur as

  19. Parasitic infection may be associated with discordant responses to QuantiFERON and tuberculin skin test in apparently healthy children and adolescents in a tuberculosis endemic setting, Ethiopia

    PubMed Central

    2013-01-01

    Background M. tuberculosis remains one of the world’s deadliest pathogens in part because of its ability to establish persistent, latent infections, which can later reactivate to cause disease. In regions of the globe where disease is endemic, as much as 50% of the population is thought to be latently infected, complicating diagnosis and tuberculosis control. The tools most commonly used for diagnosis of latent M. tuberculosis infection are the tuberculin skin test and the newer interferon-gamma release assays, both of which rely on an antigen-specific memory response as an indicator of infection. It is clear that the two tests, do not always give concordant results, but the factors leading to this are only partially understood. Methods In this study we examined 245 healthy school children aged from 12 to 20 years from Addis Ababa, a tuberculosis-endemic region, characterised them with regard to response in the tuberculin skin test and QuantIFERON™ test and assessed factors that might contribute to discordant responses. Results Although concordance between the tests was generally fair (90% concordance), there was a subset of children who had a positive QuantIFERON™ result but a negative tuberculin skin test. After analysis of multiple parameters the data suggest that discordance was most strongly associated with the presence of parasites in the stool. Conclusions Parasitic gut infections are frequent in most regions where M. tuberculosis is endemic. This study, while preliminary, suggests that the tuberculin skin test should be interpreted with caution where this may be the case. PMID:23738853

  20. A regulatory assessment of test data for reactivity accidents

    SciTech Connect

    Meyer, R.O.; Scott, H.H.; Chung, Hee M.

    1997-09-01

    An assessment is made of recent test data from France, Japan, and Russia, and of earlier test data from the U.S., in relation to the safety analysis performed for power reactors in the U.S. Considerations include mode of cladding failure, oxidation, hydriding, and pulse-width effects. From the data trend and from these considerations, it is concluded that the cladding failure threshold for fuel rods with moderate-to-high burnup is roughly 100 cal/g for BWRs and PWRs. Realistic plant calculations suggest that cladding failure would not occur for rod-ejection or rod-drop accidents and, therefore, that pellet fragmentation and enhanced fission product release from fuel pellets should not have to be considered in the safety analysis for these accidents. However, the data base is sparse and contains a lot of uncertainty.

  1. Assuring consumer safety without animal testing: a feasibility case study for skin sensitisation.

    PubMed

    Maxwell, Gavin; Aleksic, Maja; Aptula, Aynur; Carmichael, Paul; Fentem, Julia; Gilmour, Nicola; Mackay, Cameron; Pease, Camilla; Pendlington, Ruth; Reynolds, Fiona; Scott, Daniel; Warner, Guy; Westmoreland, Carl

    2008-11-01

    Allergic Contact Dermatitis (ACD; chemical-induced skin sensitisation) represents a key consumer safety endpoint for the cosmetics industry. At present, animal tests (predominantly the mouse Local Lymph Node Assay) are used to generate skin sensitisation hazard data for use in consumer safety risk assessments. An animal testing ban on chemicals to be used in cosmetics will come into effect in the European Union (EU) from March 2009. This animal testing ban is also linked to an EU marketing ban on products containing any ingredients that have been subsequently tested in animals, from March 2009 or March 2013, depending on the toxicological endpoint of concern. Consequently, the testing of cosmetic ingredients in animals for their potential to induce skin sensitisation will be subject to an EU marketing ban, from March 2013 onwards. Our conceptual framework and strategy to deliver a non-animal approach to consumer safety risk assessment can be summarised as an evaluation of new technologies (e.g. 'omics', informatics), leading to the development of new non-animal (in silico and in vitro) predictive models for the generation and interpretation of new forms of hazard characterisation data, followed by the development of new risk assessment approaches to integrate these new forms of data and information in the context of human exposure. Following the principles of the conceptual framework, we have been investigating existing and developing new technologies, models and approaches, in order to explore the feasibility of delivering consumer safety risk assessment decisions in the absence of new animal data. We present here our progress in implementing this conceptual framework, with the skin sensitisation endpoint used as a case study. PMID:19025323

  2. Test systems for the determination of glucocorticoid receptor ligand induced skin atrophy

    PubMed Central

    Schäcke, Heike; Asadullah, Khusru

    2011-01-01

    Topical glucocorticoids are highly anti-inflammatory effective but limited by their side effect potential, with skin atrophy being the most prominent one. Thus, determining the atrophogenic potential of novel compounds targeting the glucocorticoid receptor is important. Significant progress in the understanding of glucocorticoid receptor mediated molecular action has been made providing the basis for novel glucocorticoid receptor ligands with a potentially superior effect/side effect profile. Such compounds, however, need to be tested. The present gold standard for the reliable prediction of glucocorticoid induced skin atrophy are still in vivo models, however, in vitro models may replace them to some extent in the future. Indeed, advances in technologies to determine the atrophogenic potential of compounds in vitro has been made recently and promising novel test models like the human full thickness skin models are emerging. Their full predictive value, however, needs to be further evaluated. Currently, a screening approach starting with a combination of several in vitro test systems followed by subsequent testing of the most promising compounds in rodent models is recommended prior entering clinical studies with selected development compounds. PMID:22110776

  3. Skin sensitization--a critical review of predictive test methods in animals and man.

    PubMed

    Botham, P A; Basketter, D A; Maurer, T; Mueller, D; Potokar, M; Bontinck, W J

    1991-04-01

    With the exception of the Draize Test, the guinea-pig test methods currently accepted by regulatory authorities worldwide are well able to predict the potential of a material to cause skin sensitization. Nevertheless, (a) some methods are more sensitive than others (e.g. adjuvant tests are generally more sensitive than non-adjuvant tests); (b) methods cannot be sufficiently standardized to give full reproducibility of results between laboratories; and (c) most methods are based on subjective visual grading of skin reactions--difficulties thus arise when testing coloured or irritant materials. Laboratories must be able to show the sensitivity of the method(s) they use by demonstrating that positive reactions occur with mild/moderate contact allergens rather than the strong/extreme sensitizers currently recommended in certain guidelines, specifically in the EEC Test Method. The sensitivity of the adjuvant tests is such that it is possible to halve the minimum number of animals required by present regulatory guidelines without compromising the capacity of the tests to detect weak/mild sensitizers. A similar review has not yet been made for non-adjuvant tests. Alternative test methods, including some recently developed mouse models, offer several advantages, including more objective endpoints. These tests have not been extensively validated and this precludes their use at present for regulatory purposes other than to confirm the sensitization potential of a material. Two new test methods using mice, the Mouse Ear-swelling Test and the Local Lymph Node Assay, appear promising. They should undergo rigorous interlaboratory testing to determine their sensitivity and specificity. In vitro methods do not represent a viable alternative in the foreseeable future. An approach using quantitative structure-activity relationships is the most likely route to a non-animal model, but this will require considerable research, development and validation. Human sensitization tests have

  4. Tuberculin Skin Test Negativity Is Under Tight Genetic Control of Chromosomal Region 11p14-15 in Settings With Different Tuberculosis Endemicities

    PubMed Central

    Cobat, Aurélie; Poirier, Christine; Hoal, Eileen; Boland-Auge, Anne; de La Rocque, France; Corrard, François; Grange, Ghislain; Migaud, Mélanie; Bustamante, Jacinta; Boisson-Dupuis, Stéphanie; Casanova, Jean-Laurent; Schurr, Erwin; Alcaïs, Alexandre; Delacourt, Christophe; Abel, Laurent

    2015-01-01

    A substantial proportion of subjects exposed to a contagious tuberculosis case display lack of tuberculin skin test (TST) reactivity. We previously mapped a major locus (TST1) controlling lack of TST reactivity in families from an area in South Africa where tuberculosis is hyperendemic. Here, we conducted a household tuberculosis contact study in a French area where the endemicity of tuberculosis is low. A genome-wide analysis of TST negativity identified a significant linkage signal (P < 3 × 10−5) in close vicinity of TST1. Combined analysis of the 2 samples increased evidence of linkage (P = 2.4 × 10−6), further implicating genetic factors located on 11p14-15. This region overlaps the TNF1 locus controlling mycobacteria-driven tumor necrosis factor α production. PMID:25143445

  5. Skin reactivity of unsensitized monkeys upon challenge with staphylococcal enterotoxin B: a new approach for investigating the site of toxin action.

    PubMed Central

    Scheuber, P H; Golecki, J R; Kickhöfen, B; Scheel, D; Beck, G; Hammer, D K

    1985-01-01

    The correlation between skin tests and emetic responses in unsensitized monkeys was used to elucidate the cellular site of action of staphylococcal enterotoxin B (SEB). Evidence is presented that SEB administered intradermally provoked immediate-type skin reactions associated with mild degranulation of cutaneous mast cells. The cytoplasma showed signs of synthetic and metabolic activity, with formation of vesicles and increased prominence of mitochondria. Carboxymethylation of histidine residues of SEB altered the molecule (cSEB) from more alkaline components to more acidic species with increased microheterogeneity. This modification caused a loss in toxicity and completely abrogated the skin-sensitizing activity without changing the immunological specificity. cSEB, however, could compete with SEB for binding sites on the target cell surface. Previously, compound 48/80-treated skin sites behaved refractively to challenge with SEB, indicating that mediators from cutaneous mast cells are required for SEB-induced skin reactions. Skin reactions as well as emetic responses challenged with SEB were completely inhibited by H2 receptor antagonists and calcium channel blockers but not by H1 antihistamine or competitive antagonists of serotonin. This new approach provides a model for investigating the mechanisms of SEB action. Images PMID:2866161

  6. Sensitization to Food Additives in Patients with Allergy: A Study Based on Skin Test and Open Oral Challenge.

    PubMed

    Moghtaderi, Mozhgan; Hejrati, Zinatosadat; Dehghani, Zahra; Dehghani, Faranak; Kolahi, Niloofar

    2016-06-01

    There has been a great increase in the consumption of various food additives in recent years. The purpose of this study was to identify the incidence of sensitization to food additives by using skin prick test in patients with allergy and to determine the concordance rate between positive skin tests and oral challenge in hypersensitivity to additives. This cross-sectional study included 125 (female 71, male 54) patients aged 2-76 years with allergy and 100 healthy individuals. Skin tests were performed in both patient and control groups with 25 fresh food additives. Among patients with allergy, 22.4% showed positive skin test at least to one of the applied materials. Skin test was negative to all tested food additives in control group. Oral food challenge was done in 28 patients with positive skin test, in whom 9 patients showed reaction to culprit (Concordance rate=32.1%). The present study suggested that about one-third of allergic patients with positive reaction to food additives showed positive oral challenge; it may be considered the potential utility of skin test to identify the role of food additives in patients with allergy. PMID:27424134

  7. Evaluation of combinations of in vitro sensitization test descriptors for the artificial neural network-based risk assessment model of skin sensitization.

    PubMed

    Hirota, Morihiko; Fukui, Shiho; Okamoto, Kenji; Kurotani, Satoru; Imai, Noriyasu; Fujishiro, Miyuki; Kyotani, Daiki; Kato, Yoshinao; Kasahara, Toshihiko; Fujita, Masaharu; Toyoda, Akemi; Sekiya, Daisuke; Watanabe, Shinichi; Seto, Hirokazu; Takenouchi, Osamu; Ashikaga, Takao; Miyazawa, Masaaki

    2015-11-01

    The skin sensitization potential of chemicals has been determined with the use of the murine local lymph node assay (LLNA). However, in recent years public concern about animal welfare has led to a requirement for non-animal risk assessment systems for the prediction of skin sensitization potential, to replace LLNA. Selection of an appropriate in vitro test or in silico model descriptors is critical to obtain good predictive performance. Here, we investigated the utility of artificial neural network (ANN) prediction models using various combinations of descriptors from several in vitro sensitization tests. The dataset, collected from published data and from experiments carried out in collaboration with the Japan Cosmetic Industry Association (JCIA), consisted of values from the human cell line activation test (h-CLAT), direct peptide reactivity assay (DPRA), SH test and antioxidant response element (ARE) assay for chemicals whose LLNA thresholds have been reported. After confirming the relationship between individual in vitro test descriptors and the LLNA threshold (e.g. EC3 value), we used the subsets of chemicals for which the requisite test values were available to evaluate the predictive performance of ANN models using combinations of h-CLAT/DPRA (N = 139 chemicals), the DPRA/ARE assay (N = 69), the SH test/ARE assay (N = 73), the h-CLAT/DPRA/ARE assay (N = 69) and the h-CLAT/SH test/ARE assay (N = 73). The h-CLAT/DPRA, h-CLAT/DPRA/ARE assay and h-CLAT/SH test/ARE assay combinations showed a better predictive performance than the DPRA/ARE assay and the SH test/ARE assay. Our data indicates that the descriptors evaluated in this study were all useful for predicting human skin sensitization potential, although combinations containing h-CLAT (reflecting dendritic cell-activating ability) were most effective for ANN-based prediction. PMID:25824844

  8. Tests of Flammability of Cotton Fabrics and Expected Skin Burns in Microgravity

    NASA Technical Reports Server (NTRS)

    Cavanagh, Jane M.; Torvi, David A.; Gabriel, Kamiel S.; Ruff, Gary A.

    2004-01-01

    During a shuttle launch and other portions of space flight, astronauts wear specialized flame resistant clothing. However during most of their missions on board the Space Shuttle or International Space Station, astronauts wear ordinary clothing, such as cotton shirts and pants. As the behaviour of flames is considerably different in microgravity than under earth's gravity, fabrics are expected to burn in a different fashion in microgravity than when tested on earth. There is interest in determining how this change in burning behaviour may affect times to second and third degree burn of human skin, and how the results of standard fabric flammability tests conducted under earth's gravity correlate with the expected fire behaviour of textiles in microgravity. A new experimental apparatus was developed to fit into the Spacecraft Fire Safety Facility (SFSF), which is used on NASA's KC-135 low gravity aircraft. The new apparatus was designed to be similar to the apparatus used in standard vertical flammability tests of fabrics. However, rather than using a laboratory burner, the apparatus uses a hot wire system to ignite 200 mm high by 80 mm wide fabric specimens. Fabric temperatures are measured using thermocouples and/or an infrared imaging system, while flame spread rates are measured using real time observations or video. Heat flux gauges are placed between 7 and 13 mm away from the fabric specimen, so that heat fluxes from the burning fabric to the skin can be estimated, along with predicted times required to produce skin burns. In November of 2003, this new apparatus was used on the KC-135 aircraft to test cotton and cotton/polyester blend fabric specimens in microgravity. These materials were also been tested using the same apparatus in 1-g, and using a standard vertical flammability test that utilizes a flame. In this presentation, the design of the test apparatus will be briefly described. Examples of results from the KC-135 tests will be provided, including

  9. Regulatory T Cells Modulate Th17 Responses in Tuberculin skin test positive (TST+) individuals

    PubMed Central

    Babu, Subash; Bhat, Sajid Q.; Kumar, N. Pavan; Kumaraswami, V.; Nutman, Thomas B.

    2009-01-01

    Background The factors governing latency in tuberculosis (TB) are not well understood but appear to include pathogen and host factors. We have used Tuberculin skin test positivity as a tool to study cytokine responses in latent TB. Methods To identify host factors important in maintenance of TST positivity, we examined mycobacteria-specific immune responses of tuberculin skin test positive (TST+; latent TB) or negative (TST−; healthy) individuals in South India where skin test positivity can define TB latency. Results While PPD- and Mycobacterium tuberculosis culture filtrate Ag-specific Th1 and Th2 cytokines were not significantly different between the two groups, the Th17 cytokines—IL-17 and IL-23—were significantly decreased in TST+ individuals compared with the TST− individuals. This Th17 cytokine modulation was associated with significantly increased expression of CTLA-4 and Foxp3. Although CTLA-4 blockade failed to restore full production of IL-17 and IL-23 in TST+ individuals, depletion of regulatory T cells significantly increased production of these cytokines. Conclusion TST positivity is characterized by increased activity of regulatory T cells and a coincident downregulation of the Th17 response. PMID:19929695

  10. Testing and Analysis of Composite Skin/Stringer Debonding Under Multi-Axial Loading

    NASA Technical Reports Server (NTRS)

    Krueger, Ronald; Cvitkovich, Michael K.; OBrien, T. Kevin; Minguet, Pierre J.

    1999-01-01

    Damage mechanisms in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out- of-plane) loading conditions were examined. Specimens consisted of a tapered composite flange bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending . For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both in-plane tension and out-of-plane bending loads simultaneously. Specimen edges were examined on the microscope to document the damage occurrence and to identify typical damage patterns. The observations showed that, for all three load cases, failure initiated in the flange, near the flange tip, causing the flange to almost fully debond from the skin. A two-dimensional plane-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, principal stresses exceeded the transverse strength of the material in the flange area. Additionally, delaminations of various lengths were simulated in two locations where delaminations were observed. The analyses showed that unstable delamination propagation is likely to occur in one location at the loads corresponding to matrix ply crack initiation for all three load cases.

  11. Tests of Flammability of Cotton Fabrics and Expected Skin Burns in Microgravity

    NASA Technical Reports Server (NTRS)

    Cavanagh, Jane M.; Torvi, David A.; Gabriel, Kamiel S.; Ruff, Gary A.

    2004-01-01

    During a shuttle launch and other portions of space flight, astronauts wear specialized flame resistant clothing. However during most of their missions on board the Space Shuttle or International Space Station, astronauts wear ordinary clothing, such as cotton shirts and pants. As the behaviour of flames is considerably different in microgravity than under earth s gravity, fabrics are expected to burn in a different fashion in microgravity than when tested on earth. There is interest in determining how this change in burning behaviour may affect times to second and third degree burn of human skin, and how the results of standard fabric flammability tests conducted under earth s gravity correlate with the expected fire behaviour of textiles in microgravity. A new experimental apparatus was developed to fit into the Spacecraft Fire Safety Facility (SFSF), which is used on NASA s KC-135 low gravity aircraft. The new apparatus was designed to be similar to the apparatus used in standard vertical flammability tests of fabrics. However, rather than using a laboratory burner, the apparatus uses a hot wire system to ignite 200 mm high by 80 mm wide fabric specimens. Fabric temperatures are measured using thermocouples and/or an infrared imaging system, while flame spread rates are measured using real time observations or video. Heat flux gauges are placed between 7 and 13 mm away from the fabric specimen, so that heat fluxes from the burning fabric to the skin can be estimated, along with predicted times required to produce skin burns.

  12. Improved procedures for in vitro skin irritation testing of sticky and greasy natural botanicals.

    PubMed

    Molinari, J; Eskes, C; Andres, E; Remoué, N; Sá-Rocha, V M; Hurtado, S P; Barrichello, C

    2013-02-01

    Skin irritation evaluation is an important endpoint for the safety assessment of cosmetic ingredients required by various regulatory authorities for notification and/or import of test substances. The present study was undertaken to investigate possible protocol adaptations of the currently validated in vitro skin irritation test methods based on reconstructed human epidermis (RhE) for the testing of plant extracts and natural botanicals. Due to their specific physico-chemical properties, such as lipophilicity, sticky/buttery-like texture, waxy/creamy foam characteristics, normal washing procedures can lead to an incomplete removal of these materials and/or to mechanical damage to the tissues, resulting in an impaired prediction of the true skin irritation potential of the materials. For this reason different refined washing procedures were evaluated for their ability to ensure appropriate removal of greasy and sticky substances while not altering the normal responses of the validated RhE test method. Amongst the different procedures evaluated, the use of a SDS 0.1% PBS solution to remove the sticky and greasy test material prior to the normal washing procedures was found to be the most suitable adaptation to ensure efficient removal of greasy and sticky in-house controls without affecting the results of the negative control. The predictive capacity of the refined SDS 0.1% washing procedure, was investigated by using twelve oily and viscous compounds having known skin irritation effects supported by raw and/or peer reviewed in vivo data. The normal washing procedure resulted in 8 out of 10 correctly predicted compounds as compared to 9 out of 10 with the refined washing procedures, showing an increase in the predictive ability of the assay. The refined washing procedure allowed to correctly identify all in vivo skin irritant materials showing the same sensitivity as the normal washing procedures, and further increased the specificity of the assay from 5 to 6 correct

  13. The Myeloid U937 Skin Sensitization Test (U-SENS) addresses the activation of dendritic cell event in the adverse outcome pathway for skin sensitization.

    PubMed

    Piroird, Cécile; Ovigne, Jean-Marc; Rousset, Françoise; Martinozzi-Teissier, Silvia; Gomes, Charles; Cotovio, José; Alépée, Nathalie

    2015-08-01

    The U-SENS™ assay, formerly known as MUSST (Myeloid U937 Skin Sensitization Test), is an in vitro method to assess skin sensitization. Dendritic cell activation following exposure to sensitizers was modelled in the U937 human myeloid cell line by measuring the induction of the expression of CD86 by flow cytometry. The predictive performance of U-SENS™ was assessed via a comprehensive comparison analysis with the available human and LLNA data of 175 substances. U-SENS™ showed 79% specificity, 90% sensitivity and 88% accuracy. A four laboratory ring study demonstrated the transferability, reliability and reproducibility of U-SENS™, with a reproducibility of 95% within laboratories and 79% between-laboratories, showing that the U-SENS™ assay is a promising tool in a skin sensitization risk assessment testing strategy. PMID:25820135

  14. Cutaneous Surgical Denervation: A Method for Testing the Requirement for Nerves in Mouse Models of Skin Disease.

    PubMed

    Peterson, Shelby C; Brownell, Isaac; Wong, Sunny Y

    2016-01-01

    Cutaneous somatosensory nerves function to detect diverse stimuli that act upon the skin. In addition to their established sensory roles, recent studies have suggested that nerves may also modulate skin disorders including atopic dermatitis, psoriasis and cancer. Here, we describe protocols for testing the requirement for nerves in maintaining a cutaneous mechanosensory organ, the touch dome (TD). Specifically, we discuss methods for genetically labeling, harvesting and visualizing TDs by whole-mount staining, and for performing unilateral surgical denervation on mouse dorsal back skin. Together, these approaches can be used to directly compare TD morphology and gene expression in denervated as well as sham-operated skin from the same animal. These methods can also be readily adapted to examine the requirement for nerves in mouse models of skin pathology. Finally, the ability to repeatedly sample the skin provides an opportunity to monitor disease progression at different stages and times after initiation. PMID:27404892

  15. Exploring the cause of initially reactive bovine brains on rapid tests for BSE

    PubMed Central

    Dudas, Sandor; James, Jace; Anderson, Renee; Czub, Stefanie

    2015-01-01

    ABSTRACT Bovine spongiform encephalopathy (BSE) is an invariably fatal prion disease of cattle. The identification of the zoonotic potential of BSE prompted safety officials to initiate surveillance testing for this disease. In Canada, BSE surveillance is primarily focused on high risk cattle including animals which are dead, down and unable to rise, diseased or distressed. This targeted surveillance results in the submission of brain samples with a wide range of tissue autolysis and associated contaminants. These contaminants have the potential to interfere with important steps of surveillance tests resulting in initially positive test results requiring additional testing to confirm the disease status of the animal. The current tests used for BSE screening in Canada utilize the relative protease resistance of the prion protein gained when it misfolds from PrPC to PrPSc as part of the disease process. Proteinase K completely digests PrPC in normal brains, but leaves most of the PrPSc in BSE positive brains intact which is detected using anti-prion antibodies. These tests are highly reliable but occasionally give rise to initially reactive/false positive results. Test results for these reactive samples were close to the positive/negative cut-off on a sub set of test platforms. This is in contrast to all of the previous Canadian positive samples whose numeric values on these same test platforms were 10 to 100 fold greater than the test positive/negative cut-off. Here we explore the potential reason why a sample is repeatedly positive on a sub-set of rapid surveillance tests, but negative on other test platforms. In order to better understand and identify what might cause these initial reactions, we have conducted a variety of rapid and confirmatory assays as well as bacterial isolation and identification on BSE positive, negative and initially reactive samples. We observed high levels of viable bacterial contamination in initially reactive samples suggesting that the

  16. Antibiotic skin testing accompanied by provocative challenges in children is a useful clinical tool

    PubMed Central

    2013-01-01

    Background Diagnostic testing to antibiotics other than to penicillin has not been widely available, making the diagnosis of antibiotic allergy difficult and often erroneous. There is often reluctance in performing challenges to antibiotics when standardized testing is lacking. However, while the immunogenic determinants are not known for most antibiotics, a skin reaction at a non-irritating concentration (NIC) may mean that antibodies to the native form are present in the circulation. While the NIC’s for many non penicillin antibiotics have been determined in adults, the use of these concentrations for skin testing pediatric subjects prior to provocative challenge has not been done. Our objective was to determine if we could successfully uncover the true nature of antibiotic allergy in children using these concentrations for testing. Methods Children were included between 2003–2009 upon being referred to the Drug and Adverse Reaction/Toxicology (DART) clinic of the Hospital for Sick Children in Toronto, Ontario Canada. The referral needed to demonstrate that clinical care was being compromised by the limitation in antibiotic options or there was a significant medical condition for which the label of antibiotic allergy may prove detrimental. Patients were not seen if there was a suggestion of serum like sickness, Stevens Johnson Syndrome or Toxic Epidermal Necrolysis. Patients were excluded from testing if there was objective evidence of anaphylaxis. All other patients were consented to receive testing and/or challenges. A retrospective chart review was then performed of the results. Results We were able to exclude an antibiotic allergy in the majority of our patients who had a negative intradermal test result and were then challenged (>90%). Only one patient was challenged with a positive intradermal test to Cotrimoxazole because of a questionable history and this patient failed the provocative challenge. While we did not challenge more patients with positive

  17. Non-occlusive topical exposure of human skin in vitro as model for cytotoxicity testing of irritant compounds.

    PubMed

    Lönnqvist, Susanna; Briheim, Kristina; Kratz, Gunnar

    2016-02-01

    Testing of irritant compounds has traditionally been performed on animals and human volunteers. Animal testing should always be restricted and for skin irritancy mice and rabbits hold poor predictive value for irritant potential in humans. Irritant testing on human volunteers is restricted by the duration subjects can be exposed, and by the subjectivity of interpreting the visual signs of skin irritation. We propose an irritant testing system using viable human full thickness skin with the loss of cell viability in the exposed skin area as end point measurement. Skin was exposed to sodium dodecyl sulfate (SDS) at 20% concentration by non-occluded topical exposure to establish a positive control response and subsequent test compounds were statistically compared with the 20% SDS response. Cell viability and metabolism were measured with 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The model presents correlation between increased concentration of SDS and decreased viability of cells in the exposed skin area (R(2) = 0.76). We propose the model to be used for cytotoxicity testing of irritant compounds. With fully intact barrier function, the model comprises all cells present in the skin with quantifiable end point measurement. PMID:26446981

  18. Ethanol extract of Dalbergia odorifera protects skin keratinocytes against ultraviolet B-induced photoaging by suppressing production of reactive oxygen species.

    PubMed

    Ham, Sun Ah; Hwang, Jung Seok; Kang, Eun Sil; Yoo, Taesik; Lim, Hyun Ho; Lee, Won Jin; Paek, Kyung Shin; Seo, Han Geuk

    2015-01-01

    Dalbergia odorifera T. Chen (Leguminosae), an indigenous medicinal herb, has been widely used in northern and eastern Asia to treat diverse diseases. Here, we investigated the anti-senescent effects of ethanolic extracts of Dalbergia odorifera (EEDO) in ultraviolet (UV) B-irradiated skin cells. EEDO significantly inhibited UVB-induced senescence of human keratinocytes in a concentration-dependent manner, concomitant with inhibition of reactive oxygen species (ROS) generation. UVB-induced increases in the levels of p53 and p21, biomarkers of cellular senescence, were almost completely abolished in the presence of EEDO. Sativanone, a major constituent of EEDO, also attenuated UVB-induced senescence and ROS generation in keratinocytes, indicating that sativanone is an indexing (marker) molecule for the anti-senescence properties of EEDO. Finally, treatment of EEDO to mice exposed to UVB significantly reduced ROS levels and the number of senescent cells in the skin. Thus, EEDO confers resistance to UVB-induced cellular senescence by inhibiting ROS generation in skin cells. PMID:25560618

  19. New Skin Test for Detection of Bovine Tuberculosis on the Basis of Antigen-Displaying Polyester Inclusions Produced by Recombinant Escherichia coli

    PubMed Central

    Chen, Shuxiong; Parlane, Natalie A.; Lee, Jason; Wedlock, D. Neil; Buddle, Bryce M.

    2014-01-01

    The tuberculin skin test for diagnosing tuberculosis (TB) in cattle lacks specificity if animals are sensitized to environmental mycobacteria, as some antigens in purified protein derivative (PPD) prepared from Mycobacterium bovis are present in nonpathogenic mycobacteria. Three immunodominant TB antigens, ESAT6, CFP10, and Rv3615c, are present in members of the pathogenic Mycobacterium tuberculosis complex but absent from the majority of environmental mycobacteria. These TB antigens have the potential to enhance skin test specificity. To increase their immunogenicity, these antigens were displayed on polyester beads by translationally fusing them to a polyhydroxyalkanoate (PHA) synthase which mediated formation of antigen-displaying inclusions in recombinant Escherichia coli. The most common form of these inclusions is poly(3-hydroxybutyric acid) (PHB). The respective fusion proteins displayed on these PHB inclusions (beads) were identified using tryptic peptide fingerprinting analysis in combination with matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). The surface exposure and accessibility of antigens were assessed by enzyme-linked immunosorbent assay (ELISA). Polyester beads displaying all three TB antigens showed greater reactivity with TB antigen-specific antibody than did beads displaying only one TB antigen. This was neither due to cross-reactivity of antibodies with the other two antigens nor due to differences in protein expression levels between beads displaying single or three TB antigens. The triple-antigen-displaying polyester beads were used for skin testing of cattle and detected all cattle experimentally infected with M. bovis with no false-positive reactions observed in those sensitized to environmental mycobacteria. The results suggested applicability of TB antigen-displaying polyester inclusions as diagnostic reagents for distinguishing TB-infected from noninfected animals. PMID:24532066

  20. Chemical Characterization and Reactivity Testing of Fuel-Oxidizer Reaction Product (Test Report)

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The product of incomplete reaction of monomethylhydrazine (MMH) and nitrogen tetroxide (NTO) propellants, or fuel-oxidizer reaction product (FORP), has been hypothesized as a contributory cause of an anomaly which occurred in the chamber pressure (PC) transducer tube on the Reaction Control Subsystem (RCS) aft thruster 467 on flight STS-51. A small hole was found in the titanium-alloy PC tube at the first bend below the pressure transducer. It was surmised that the hole may have been caused by heat and pressure resulting from ignition of FORP. The NASA Johnson Space Center (JSC) White Sands Test Facility (WSTF) was requested to define the chemical characteristics of FORP, characterize its reactivity, and simulate the events in a controlled environment which may have lead to the Pc-tube failure. Samples of FORP were obtained from the gas-phase reaction of MMH with NTO under laboratory conditions, the pulsed firings of RCS thrusters with modified PC tubes using varied oxidizer or fuel lead times, and the nominal RCS thruster firings at WSTF and Kaiser-Marquardt. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), accelerating rate calorimetry (ARC), ion chromatography (IC), inductively coupled plasma (ICP) spectrometry, thermogravimetric analysis (TGA) coupled to FTIR (TGA/FTIR), and mechanical impact testing were used to qualitatively and quantitatively characterize the chemical, thermal, and ignition properties of FORP. These studies showed that the composition of FORP is variable but falls within a limited range of compositions that depends on the fuel loxidizer ratio at the time of formation, composition of the post-formation atmosphere (reducing or oxidizing), and reaction or postreaction temperature. A typical composition contains methylhydrazinium nitrate (MMHN), ammonium nitrate (AN), methylammonium nitrate (MAN), and trace amounts of hydrazinium nitrate and 1,1-dimethylhydrazinium nitrate. The thermal decomposition

  1. A Tracer Test to Characterize Treatment of TCE in a Permeable Reactive Barrier

    EPA Science Inventory

    A tracer test was conducted to characterize the flow of ground water surrounding a permeable reactive barrier constructed with plant mulch (a biowall) at the OU-1 site on Altus Air Force Base, Oklahoma. This biowall is intended to intercept and treat ground water contaminated by ...

  2. A new method of wound treatment: targeted therapy of skin wounds with reactive oxygen species-responsive nanoparticles containing SDF-1α

    PubMed Central

    Tang, Tao; Jiang, Hao; Yu, Yuan; He, Fang; Ji, Shi-zhao; Liu, Ying-ying; Wang, Zhong-shan; Xiao, Shi-chu; Tang, Cui; Wang, Guang-Yi; Xia, Zhao-Fan

    2015-01-01

    Objective To accelerate wound healing through promoting vascularization by using reactive oxygen species (ROS)-responsive nanoparticles loaded with stromal cell-derived factor-1α(SDF-1α). Methods The ROS-reactive nanomaterial poly-(1,4-phenyleneacetone dimethylene thioketal) was synthesized, and its physical and chemical properties were characterized. ROS-responsive nanoparticles containing SDF-1α were prepared through a multiple emulsion solvent evaporation method. The loading capacity, stability, activity of the encapsulated protein, toxicity, and in vivo distribution of these nanoparticles were determined. These nanoparticles were administered by intravenous infusion to mice with full-thickness skin defects to study their effects on the directed chemotaxis of bone marrow mesenchymal stem cells, wound vascularization, and wound healing. Results The synthesized ROS-reactive organic polymer poly-(1,4-phenyleneacetone dimethylene thioketal) possessed a molecular weight of approximately 11.5 kDa with a dispersity of 1.97. ROS-responsive nanoparticles containing SDF-1α were prepared with an average diameter of 110 nm and a drug loading capacity of 1.8%. The encapsulation process showed minimal effects on the activity of SDF-1α, and it could be effectively released from the nanoparticles in the presence of ROS. Encapsulated SDF-1α could exist for a long time in blood. In mice with full-thickness skin defects, SDF-1α was effectively released and targeted to the wounds, thus promoting the chemotaxis of bone marrow mesenchymal stem cells toward the wound and its periphery, inducing wound vascularization, and accelerating wound healing. PMID:26527874

  3. In Chemico Evaluation of Tea Tree Essential Oils as Skin Sensitizers: Impact of the Chemical Composition on Aging and Generation of Reactive Species.

    PubMed

    Avonto, Cristina; Chittiboyina, Amar G; Wang, Mei; Vasquez, Yelkaira; Rua, Diego; Khan, Ikhlas A

    2016-07-18

    Tea tree oil (TTO) is an essential oil obtained from the leaves of Melaleuca alternifolia, M. linariifolia, or M. dissitiflora. Because of the commercial importance of TTO, substitution or adulteration with other tea tree species (such as cajeput, niaouli, manuka, or kanuka oils) is common and may pose significant risks along with perceived health benefits. The distinctive nature, qualitative and quantitative compositional variation of these oils, is responsible for the various pharmacological as well as adverse effects. Authentic TTOs (especially aged ones) have been identified as potential skin sensitizers, while reports of adverse allergic reactions to the other tea trees essential oils are less frequent. Chemical sensitizers are usually electrophilic compounds, and in chemico methods have been developed to identify skin allergens in terms of their ability to bind to biological nucleophiles. However, little information is available on the assessment of sensitization potential of mixtures, such as essential oils, due to their complexity. In the present study, 10 "tea tree" oils and six major TTO constituents have been investigated for their sensitization potential using a fluorescence in chemico method. The reactivity of authentic TTOs was found to correlate with the age of the oils, while the majority of nonauthentic TTOs were less reactive, even after aging. Further thio-trapping experiments with DCYA and characterization by UHPLC-DAD-MS led to the identification of several possible DCYA-adducts which can be used to deduce the structure of the candidate reactive species. The major TTO components, terpinolene, α-terpinene, and terpinene-4-ol, were unstable under accelerated aging conditions, which led to the formation of several DCYA-adducts. PMID:27286037

  4. Derivation and application of mathematical model for well test analysis with variable skin factor in hydrocarbon reservoirs

    NASA Astrophysics Data System (ADS)

    Liu, Pengcheng; Li, Wenhui; Xia, Jing; Jiao, Yuwei; Bie, Aifang

    2016-06-01

    Skin factor is often regarded as a constant in most of the mathematical model for well test analysis in oilfields, but this is only a kind of simplified treatment with the actual skin factor changeable. This paper defined the average permeability of a damaged area as a function of time by using the definition of skin factor. Therefore a relationship between a variable skin factor and time was established. The variable skin factor derived was introduced into existing traditional models rather than using a constant skin factor, then, this newly derived mathematical model for well test analysis considering variable skin factor was solved by Laplace transform. The dimensionless wellbore pressure and its derivative changed with dimensionless time were plotted with double logarithm and these plots can be used for type curve fitting. The effects of all the parameters in the expression of variable skin factor were analyzed based on the dimensionless wellbore pressure and its derivative. Finally, actual well testing data were used to fit the type curves developed which validates the applicability of the mathematical model from Sheng-2 Block, Shengli Oilfield, China.

  5. The Results of Autologous Skin Test in Patients with Chronic Urticaria in Hamadan, Iran

    PubMed Central

    Safari, Mojgan; Sayemiri, Hooshyar

    2016-01-01

    Introduction The etiology of chronic urticaria is unknown in many cases. In this study, we demonstrated the presence of autoimmune antibodies in patients with chronic urticaria by using of the Autologous Serum Skin Test (ASST). Methods We performed a cross-sectional study to detect the presence of autologous antibodies in the serum of 38 patients (25 females and 13 males) with idiopathic chronic urticaria who were referred to the Hamedan Allergy Clinic in 2014. All of the necessary tests for demonstrating chronic urticaria were performed, including complete blood count (CBC), thyroid and liver functionality tests, and the prick test but they did not confirm the cause of chronic urticaria. We conducted the Autologous Serum Skin Test on the patients and analyzed the results. Results In 15 patients (39%), the ASST was positive. Of the 15 patients with positive autoimmune chronic urticaria, five patients (33%) were males, and 10 patients (67%) were females. Conclusion We concluded that many patients with chronic urticaria have autoimmune urticaria. It is the reason for the lack of the response to treatment with common medications for urticaria. New ways of treatment must be considered for them. PMID:27504169

  6. Efficacy of skin barrier creams (II). Ineffectiveness of a popular "skin protector" against various irritants in the repetitive irritation test in the guinea pig.

    PubMed

    Frosch, P J; Schulze-Dirks, A; Hoffmann, M; Axthelm, I

    1993-08-01

    A popular "skin protector" consisting of an emulsion-like foam of lipophilic and hydrophilic substances (Marly skin) was evaluated in a previously described repetitive irritation guinea pig model. The product failed to inhibit the irritation due to sodium lauryl sulphate and toluene. In striking contrast to the recommended use, the irritant response of sodium hydroxide was aggravated, as demonstrated by significant differences for all test parameters (clinical score for erythema and scaling, transepidermal water loss, blood flow volume). The results show that protection against chemical irritants may be quite specific and that some formulations may actually be harmful. PMID:8365180

  7. Sensitivity Comparison of the Skin Prick Test and Serum and Fecal Radio Allergosorbent Test (RAST) in Diagnosis of Food Allergy in Children

    PubMed Central

    Kianifar, Hamid Reza; Pourreza, Alireza; Jabbari Azad, Farahzad; Yousefzadeh, Hadis; Masomi, Fatemeh

    2016-01-01

    Background: Diagnosis of food allergy is difficult in children. Food allergies are diagnosed using several methods that include medical histories, clinical examinations, skin prick and serum-specific immunoglobulin E (IgE) tests, radio-allergosorbent test (RAST), food challenge, and supervised elimination diets. In this study we evaluated allergies to cow's milk, egg, peanut, and fish in children with suspected food allergies with skin prick tests and serum and feces RAST. Methods: Forty-one children with clinical symptoms of food allergies were enrolled in the study. Skin prick tests and serum and fecal RAST were performed and compared with challenge tests. Results: The most common sites of food allergy symptoms were gastrointestinal (82.9%) and skin (48.8%). 100% of the patients responded to the challenge tests with cow’s milk, egg, peanut, and fish. 65% of the patients tested positive with the skin prick test, 12.1% tested positive with serum RAST, and 29.2% tested positive with fecal RAST. Conclusion: The skin prick test was more sensitive than serum or fecal RAST, and fecal RAST was more than twice as sensitive as serum RAST.

  8. Reactivity to nickel sulfate at sodium lauryl sulfate pretreated skin sites is higher in atopics: an echographic evaluation by means of image analysis performed on 20 MHz B-scan recordings.

    PubMed

    Seidenari, S

    1994-07-01

    The aim of this study was to establish an objectively assessable procedure simulating simultaneous exposure to irritants and allergens in domestic and occupational environments, in order to evaluate differences in the reactivity to the combination of these substances in atopic and non-atopic nickel-sensitized subjects. Thirty-four nickel-sensitive patients, 20 of whom were affected by atopic dermatitis, underwent four patch tests with NiSO4 0.05% aq. on two adjacent sites of both volar forearms, with a 24-h application time. Two of the test sites were treated with sodium lauryl sulfate (SLS) 5% for 30 min, before application of the nickel sulfate preparation. Echographic recordings were performed by a 20-MHz B-scanner and processed by an image analysis program, providing a numerical representation of the picture data, based on the attribution of fictional values to the amplitudes of the echoes. The dermal inflammatory reaction was quantified by an amplitude band, marking the hypo-reflecting part of the dermis, whereas epidermal damage was assessed by a band highlighting the entrance echo. Pre-treatment with SLS of the skin area where nickel sulfate was subsequently applied greatly enhanced the allergic response at 24 and 72 h, both in subjects with atopic dermatitis and in subjects with allergic contact dermatitis. However, in atopics, the increase in the allergic reactivity after irritation of the skin was more pronounced both by clinical and by echographic evaluation. These observations stress the importance of the concurrent action of irritants and allergens in maintaining the dermatitis in atopics. PMID:7976078

  9. Wavelet analysis of skin perfusion to assess the effects of FREMS therapy before and after occlusive reactive hyperemia.

    PubMed

    Popa, Stefan Octavian; Ferrari, Myriam; Andreozzi, Giuseppe Maria; Martini, Romeo; Bagno, Andrea

    2015-11-01

    Laser Doppler Fluxmetry is used to evaluate the hemodynamics of skin microcirculation. Laser Doppler signals contain oscillations due to fluctuations of microvascular perfusion. By performing spectral analysis, six frequency intervals from 0.005 to 2 Hz have been identified and assigned to distinct cardiovascular structures: heart, respiration, vascular myocites, sympathetic terminations and endothelial cells (dependent and independent on nitric oxide). Transcutaneous electrical pulses are currently applied to treat several diseases, i.e. neuropathies and chronic painful leg ulcers. Recently, FREMS (Frequency Rhythmic Electrical Modulation System) has been applied to vasculopathic patients, too. In this study Laser Doppler signals of skin microcirculation were measured in five patients with intermittent claudication, before and after the FREMS therapy. Changes in vascular activities were assessed by wavelet transform analysis. Preliminary results demonstrate that FREMS induces alterations in vascular activities. PMID:26391066

  10. Assessment of electrochemical potentiokinetic reactivation tests to qualify stainless steel for nitric acid service

    SciTech Connect

    Olsen, A.R.; Dillon, J.J.; Peters, A.H.; Clift, T.L.

    1986-12-31

    To minimize the costs and delivery time delays associated with purchasing type 304L stainless steel materials for service in nitric-acid-containing media, an alternative to the current Oak Ridge Y-12 Plant requirement of testing in accordance with American Society for Testing and Materials (ASTM) A 262, Practice C (the boiling nitric acid test), is being sought. A possible candidate is the electrochemical potentiokinetic reactivation (EPR) test being developed for the nuclear industry and under consideration for acceptance as an ASTM standard. Based on a review of the literature and some limited screening tests, this test, as currently proposed, is not a suitable substitute for the nitric acid test. However, with additional development the EPR test is a likely candidate for providing a quantitative substitute for the current qualitative oxalic acid etching (ASTM A 282, Practice A) often used to accept, but not reject, materials for use in a nitric acid medium.

  11. Melanoma Genetic Testing, Counseling, and Adherence to Skin Cancer Prevention and Detection Behaviors

    PubMed Central

    Glanz, Karen; Volpicelli, Kathryn; Kanetsky, Peter A.; Ming, Michael E.; Schuchter, Lynn M.; Jepson, Christopher; Domchek, Susan M.; Armstrong, Katrina

    2013-01-01

    Background Little is known about the impact of knowledge of CDKN2A and MC1R genotype on melanoma prevention behaviors like sun avoidance and skin examination in the context of familial melanoma. Methods 73 adults with a family history of melanoma were randomly assigned to be offered individualized CDKN2A and MC1R genotyping results in the context of a genetic counseling session, or the standard practice of not being offered counseling or disclosure of genotyping results. Mixed effects or longitudinal logistic models were used to determine whether the intervention affected change in sun protection habits, skin examinations and perception and beliefs related to melanoma risk, prevention, and genetic counseling. Results All participants in the intervention group who attended genetic counseling sessions chose to receive their test results. From baseline to follow-up, participants in the intervention group reported an increase in the frequency of skin self-examinations compared to a slight decrease in the control group (p=0.002). Participants in the intervention group reported a smaller decrease in frequency of wearing a shirt with long sleeves than did participants in the control group (p =0.047). No effect of the intervention was noted for other outcomes. Conclusions Feedback of CDKN2A and MC1R genotype among families without known pathogenic CDKN2A mutations does not appear to decrease sun protection behaviors. Impact While disclosure of CDKN2A and MC1R genotype did not have negative effects on prevention, the benefits of communicating this information remain unclear. The small number of families who tested positive for CDKN2A mutations in this study is a limitation. PMID:23392000

  12. Apigenin, a bioactive flavonoid from Lycopodium clavatum, stimulates nucleotide excision repair genes to protect skin keratinocytes from ultraviolet B-induced reactive oxygen species and DNA damage.

    PubMed

    Das, Sreemanti; Das, Jayeeta; Paul, Avijit; Samadder, Asmita; Khuda-Bukhsh, Anisur Rahman

    2013-10-01

    In this study, we examined the antioxidative and the DNA protective potentials of apigenin, a flavonoid polyphenol isolated from Lycopodium clavatum, in both in-vitro (HaCaT skin keratinocytes) and in-vivo (mice) models against UV-B radiation. We used DAPI staining in UV-B-irradiated HaCaT skin keratinocytes pre-treated with and without apigenin to assess DNA damage. We also used a flow-cytometric analysis in mice exposed to UV-B radiation with or without topical application of apigenin to assess, through a comet assay, chromosomal aberrations and quanta from reactive oxygen species (ROS) generation. Data from the stability curves for the Gibb's free energy determined from a melting-temperature profile study indicated that apigenin increased the stability of calf thymus DNA. Immunofluorescence studies revealed that apigenin caused a reduction in the number of cyclobutane pyrimidine dimers (CPDs) after 24 h, the time at which the nucleotide excision repair (NER) genes were activated. Thus, apigenin accelerated reversal of UV-B-induced CPDs through up-regulation of NER genes, removal of cyclobutane rings, inhibition of ROS generation, and down-regulation of NF-κB and MAPK, thereby revealing the precise mechanism of DNA repair. PMID:24139463

  13. Tamarind seed coat extract restores reactive oxygen species through attenuation of glutathione level and antioxidant enzyme expression in human skin fibroblasts in response to oxidative stress

    PubMed Central

    Nakchat, Oranuch; Nalinratana, Nonthaneth; Meksuriyen, Duangdeun; Pongsamart, Sunanta

    2014-01-01

    Objective To investigate the role and mechanism of tamarind seed coat extract (TSCE) on normal human skin fibroblast CCD-1064Sk cells under normal and oxidative stress conditions induced by hydrogen peroxide (H2O2). Methods Tamarind seed coats were extracted with boiling water and then partitioned with ethyl acetate before the cell analysis. Effect of TSCE on intracellular reactive oxygen species (ROS), glutathione (GSH) level, antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase activity including antioxidant protein expression was investigated. Results TSCE significantly attenuated intracellular ROS in the absence and presence of H2O2 by increasing GSH level. In the absence of H2O2, TSCE significantly enhanced SOD and catalase activity but did not affected on GPx. Meanwhile, TSCE significantly increased the protein expression of SOD and GPx in H2O2-treated cells. Conclusions TSCE exhibited antioxidant activities by scavenging ROS, attenuating GSH level that could protect human skin fibroblast cells from oxidative stress. Our results highlight the antioxidant mechanism of tamarind seed coat through an antioxidant enzyme system, the extract potentially benefits for health food and cosmeceutical application of tamarind seed coat. PMID:25182723

  14. pH profiles in human skin: influence of two in vitro test systems for drug delivery testing.

    PubMed

    Wagner, Heike; Kostka, Karl Heinz; Lehr, Claus Michael; Schaefer, Ulrich F

    2003-01-01

    Investigations to determine pH profiles across human stratum corneum (SC), in vivo as well as in vitro, were carried out using the tape stripping technique and a flat surface pH electrode. This method was extended to the deeper skin layers (=viable epidermis+dermis; DSL) in vitro. Statistically significant changes in the pH values were detected in the SC between in vivo and in vitro investigations and also between male and female skin in vivo. For the DSL, no gender-dependent differences in pH were observed. While the results achieved for the SC are in accordance with data already published in the literature, the values for the DSL were surprising: An alkaline pH, with a steep increase of about two pH units in the first 100 microm of the DSL and a plateau of this level was thereafter detected. Research was also done to examine the influence of different in vitro test systems on the results of pH measurements across the skin. A permeation model (Franz diffusion cell; FD-C) and a penetration model (Saarbruecken penetration model; SB-M) were compared. Experiments were carried out concerning the incubation time as well as the pH of the acceptor solution in the FD-C. Independent of the test system used, no change in the pH profiles could be observed for the SC, but a strong effect of the acceptor medium and its pH on the pH profiles across the DSL could be demonstrated using the FD-C, which showed itself partly after 30 min in statistically significant differences between incubated and formerly frozen skin. The results after the use of buffer solutions with different pH values, the pH across the DSL seemed to come into line with the one of the buffer solution, which was investigated for acidic as well as alkaline pH values. The results obtained with the flat surface pH electrode were confirmed using two different dyes: the pH-dependent fluorescent dye carboxy-SNARF-1 and the pH indicator bromthymolblue. PMID:12551704

  15. The dilemma of the negative skin test reactors with a history of venom anaphylaxis: will this always be the case?

    PubMed

    Bilò, M B; Brianzoni, F; Cinti, B; Napoli, G; Bonifazi, F

    2005-11-01

    The loss of sensitization over time, the involvement of a different pathogenetic mechanism and the poor sensitivity of diagnostic tests have been included among the causes of a non IgE-mediated anaphylaxis triggered by an insect sting. To provide further insight into this topic we describe the case of a patient suffering from urticaria pigmentosa, anaphylactic shock due to a Vespid sting and monosensitive to Polistes dominulus venom, who was previous diagnosed with non-IgE mediated insect sting anaphylaxis in subjects with urticaria pigmentosa. Therefore ultra-rush specific immunotherapy using an acqueous Polistes dominulus venom extract was performed over two mornings until a total dose of 100mcg was reached without any side effects. Presently the patient is undergoing maintenance therapy with a depot Polistes dominulus venom extract at 4-weekly intervals and is free of side effects. In conclusion, despite the high cross-reactivity among the venoms of the various species of Polistes, recent evidence of a selective specificity unique to European Polistes allergens raises the problem of the need to make the American Polistes venom as well as that of Polistes dominulus (a very common insect in Europe) available both for diagnostic and therapeutic purposes. Besides the fact that the presence of urticaria pigmentosa alone could have explained the anaphylactic reaction to the aspecific stimulation triggered by the venom, this case history also demonstrates that omitting to perform skin tests for Polistes dominulus venom would have led to the same misdiagnosis of non IgE-mediated anaphylaxis and served only to further delay commencing specific immunotherapy. PMID:16453965

  16. Reactive Power Laboratory: Synchronous Condenser Testing&Modeling Results - Interim Report

    SciTech Connect

    Henry, SD

    2005-09-27

    The subject report documents the work carried out by Oak Ridge National Laboratory (ORNL) during months 5-7 (May-July 2005) of a multi-year research project. The project has the overall goal of developing methods of incorporating distributed energy (DE) that can produce reactive power locally and for injecting into the distribution system. The objective for this new type of DE is to be able to provide voltage regulation and dynamic reactive power reserves without the use of extensive communication and control systems. The work performed over this three-month period focused on four aspects of the overall objective: (1) characterization of a 250HP (about 300KVAr) synchronous condenser (SC) via test runs at the ORNL Reactive Power Laboratory; (2) development of a data acquisition scheme for collecting the necessary voltage, current and power readings at the synchronous condenser and on the distribution system; (3) development of algorithms for analyzing raw test data from the various test runs; and (4) validation of a steady-state model for the synchronous condenser via the use of a commercial software package to study its effects on the ORNL 13.8/2.4kV distribution network.

  17. Testing the developmental distinctiveness of male proactive and reactive aggression with a nested longitudinal experimental intervention.

    PubMed

    Barker, Edward D; Vitaro, Frank; Lacourse, Eric; Fontaine, Nathalie M G; Carbonneau, Rene; Tremblay, Richard E

    2010-01-01

    An experimental preventive intervention nested into a longitudinal study was used to test the developmental distinctiveness of proactive and reactive aggression. The randomized multimodal preventive intervention targeted a subsample of boys rated disruptive by their teachers. These boys were initially part of a sample of 895 boys, followed from kindergarten to 17 years of age. Semiparametric analyses of developmental trajectories for self-reported proactive and reactive aggression (between 13 and 17 years of age) indicated three trajectories for each type of aggression that varied in size and shape (Low, Moderate, and High Peaking). Intent-to-treat comparisons between the boys in the prevention group and the control group confirmed that the preventive intervention between 7 and 9 years of age, which included parenting skills and social skills training, could impact the development of reactive more than proactive aggression. The intervention effect identified in reactive aggression was related to a reduction in self-reported coercive parenting. The importance of these results for the distinction between subtypes of aggressive behaviors and the value of longitudinal-experimental studies from early childhood onward is discussed. PMID:20052694

  18. [A Case of Rocuronium Anaphylaxis in which Anesthesia was Safely Performed after Selection of an Alternative Drug after a Skin Test].

    PubMed

    Naruse, Satoshi; Iwata, Hiroki; Suzuki, Kota; Uraoka, Masahiro; Katoh, Takasumi; Sato, Shigehito

    2016-06-01

    We report our experience of a patient with a history of anaphylactic shock suspected to be caused by rocuronium who was scheduled to undergo hepatic tumor resection. The patient was a 17-year-old female (height : 166 cm, weight : 46 kg). During general anesthesia at another hospital several years ago, she had an anaphylactic shock, and rocuronium was suspected to be the offending drug. To collect information and search for the cause, skin tests were performed for rocuronium, vecuronium and suxamethonium. She was positive for rocuronium, and negative for other drugs. At anesthesia induction, we administered vecuronium and confirmed no development of anaphylaxis before commencement of surgery. In the perioperative period, she had no symptoms that indicated anaphylaxis. Since there is potential high cross-reactivity among muscle relaxants, it is important to perform a test for alternative drugs when a muscle relaxant may be a cause of anaphylaxis. Selection and administration of an alternative drug should be carefully performed, even when a skin test is negative for the alternative drug. PMID:27483667

  19. Predictive value of the tuberculin skin test and QuantiFERON-tuberculosis Gold In-Tube test for development of active tuberculosis in hemodialysis patients

    PubMed Central

    Seyhan, Ekrem Cengiz; Gunluoglu, Gulşah; Gunluoglu, Mehmet Zeki; Tural, Seda; Sökücü, Sinem

    2016-01-01

    BACKGROUND: Hemodialysis (HD) patients are at increased risk of reactivation of latent tuberculosis infection (LTBI) compared with the general population. QuantiFERON-TB Gold (QFT-G) for LTBI detection is more promising than tuberculin skin test (TST) in HD patients. AIM: In our study, we evaluated the value of the TST and QFT-G In-Tube (QFG-IT) test in the development of active tuberculosis (TB), in the HD patients, and in healthy controls. METHODS: The study enrolled 95 HD patients and ninety age-matched, healthy controls. The TST and QFG-IT were performed. All the subjects were followed up 5 years for active TB disease. RESULTS: Compared to the healthy controls, a high prevalence of LTBI was found in the HD patients by QFG-IT (41% vs. 25%). However, no significant difference was detected by TST (32% vs. 31%). Four HD patients and one healthy control progressed to active TB disease within the 5-year follow-up. For active TB discovered subjects, QFG-IT was positive in all, but TST was positive in two (one patient and one healthy control). In HD patients; sensitivity, specificity, positive and negative predictive values of QFG-IT, and TST for active TB was 100% and 25%, 62% and 67%, 10%, and 3%, and 100% and 95%, respectively. Receiver operating curve analysis revealed that the results are significantly different (P = 0.04). CONCLUSION: QFG-IT test is a more useful diagnostic method than TST for detecting those who will progress to active TB in HD patients. PMID:27168859

  20. Sensitization to Aeroallergens in Patients with Respiratory Allergies Based on Skin-Prick Test Results

    PubMed Central

    Lokaj-Berisha, V; Berisha, N; Lumezi, B; Ahmetaj, L; Bejtullahu, G; Karahoda, N; Pupovci, H

    2012-01-01

    Background: The aim of this study was to identify the most common aeroallergens in patients with asthma and rhinitis. Methods: The study enrolled 102 participants including 64 patients with respiratory allergies (among them 15 were clinically diagnosed as asthma patients, 41 with rhinitis, 8 were both) and 38 healthy controls. All of participants were subject of skin prick tests (SPT) with series of common allergenic extracts. Sera from all participants were tested for total IgE and eosinophil count. To measure airflow limitation and reversibility in asthma patients the pulmonary function testing were carried out. Results: M/F ratio was 1:1.6 in patients and 1:0.7 in control group with mean age 28.88 year (SD 13.16; range 6 – 55 year) and 20.47 respectively (SD 1.16; range 19–23 year). The most common risk factors in these patients were total IgE more than 100 IU/ml, eosinophils above 4% and positive family history of atopy. Skin prick testing results showed prevalence rates for allergen groups in this manner: house dust mites 81.3 %, pollens 57.8 %, animal dandruff 12.5% and moulds 4.9%. Polysensitization was common in 51.6% of all sensitized patients being positive to more than one group of allergens. Conclusion: House dust mites are the main sensitizing allergens among our allergic patients as well as healthy controls. Next in importance, in all participants, are grasses. This pattern of prevalence was expected based on herbal geography, climate and specially lifestyle. It was also compatible with the results from studies carried out in places with the same habitat. PMID:23304660

  1. Laser heat stimulation of tiny skin areas adds valuable information to quantitative sensory testing in postherpetic neuralgia.

    PubMed

    Franz, Marcel; Spohn, Dorothee; Ritter, Alexander; Rolke, Roman; Miltner, Wolfgang H R; Weiss, Thomas

    2012-08-01

    Patients suffering from postherpetic neuralgia often complain about hypo- or hypersensation in the affected dermatome. The loss of thermal sensitivity has been demonstrated by quantitative sensory testing as being associated with small-fiber (Aδ- and C-fiber) deafferentation. We aimed to compare laser stimulation (radiant heat) to thermode stimulation (contact heat) with regard to their sensitivity and specificity to detect thermal sensory deficits related to small-fiber dysfunction in postherpetic neuralgia. We contrasted detection rate of laser stimuli with 5 thermal parameters (thresholds of cold/warm detection, cold/heat pain, and sensory limen) of quantitative sensory testing. Sixteen patients diagnosed with unilateral postherpetic neuralgia and 16 age- and gender-matched healthy control subjects were tested. Quantitative sensory testing and laser stimulation of tiny skin areas were performed in the neuralgia-affected skin and in the contralateral homologue of the neuralgia-free body side. Across the 5 thermal parameters of thermode stimulation, only one parameter (warm detection threshold) revealed sensory abnormalities (thermal hypoesthesia to warm stimuli) in the neuralgia-affected skin area of patients but not in the contralateral area, as compared to the control group. In contrast, patients perceived significantly less laser stimuli both in the affected skin and in the contralateral skin compared to controls. Overall, laser stimulation proved more sensitive and specific in detecting thermal sensory abnormalities in the neuralgia-affected skin, as well as in the control skin, than any single thermal parameter of thermode stimulation. Thus, laser stimulation of tiny skin areas might be a useful diagnostic tool for small-fiber dysfunction. PMID:22657400

  2. Current status of pharmacogenomics testing for anti-tumor drug therapies: approaches to non-melanoma skin cancer.

    PubMed

    Grealy, Rebecca; Griffiths, Lyn R

    2009-01-01

    Skin cancer is one of the most commonly occurring cancer types, with substantial social, physical, and financial burdens on both individuals and societies. Although the role of UV light in initiating skin cancer development has been well characterized, genetic studies continue to show that predisposing factors can influence an individual's susceptibility to skin cancer and response to treatment. In the future, it is hoped that genetic profiles, comprising a number of genetic markers collectively involved in skin cancer susceptibility and response to treatment or prognosis, will aid in more accurately informing practitioners' choices of treatment. Individualized treatment based on these profiles has the potential to increase the efficacy of treatments, saving both time and money for the patient by avoiding the need for extensive or repeated treatment. Increased treatment responses may in turn prevent recurrence of skin cancers, reducing the burden of this disease on society. Currently existing pharmacogenomic tests, such as those that assess variation in the metabolism of the anticancer drug fluorouracil, have the potential to reduce the toxic effects of anti-tumor drugs used in the treatment of non-melanoma skin cancer (NMSC) by determining individualized appropriate dosage. If the savings generated by reducing adverse events negate the costs of developing these tests, pharmacogenomic testing may increasingly inform personalized NMSC treatment. PMID:19537842

  3. Quiz: Test Your Skin Cancer IQ | NIH MedlinePlus the Magazine

    MedlinePlus

    ... most dangerous form of skin cancer is melanoma squamous cell carcinoma basal cell carcinoma 4. The most common type of skin cancer is melanoma squamous cell carcinoma basal cell carcinoma 5. Men tend to develop ...

  4. Characterization of the mechanical properties of skin by inverse analysis combined with the indentation test.

    PubMed

    Delalleau, Alexandre; Josse, Gwendal; Lagarde, Jean-Michel; Zahouani, Hassan; Bergheau, Jean-Michel

    2006-01-01

    This study proposes a new method to determine the mechanical properties of human skin by the use of the indentation test [Pailler-Mattei, 2004. Caractérisation mécanique et tribologique de la peau humaine in vivo, Ph.D. Thesis, ECL-no. 2004-31; Pailler-Mattei, Zahouani, 2004. Journal of Adhesion Science and Technology 18, 1739-1758]. The principle of the measurements consists in applying an in vivo compressive stress [Zhang et al., 1994. Proceedings of the Institution of Mechanical Engineers 208, 217-222; Bosboom et al., 2001. Journal of Biomechanics 34, 1365-1368; Oomens et al., 1984. Selected Proceedings of Meetings of European Society of Biomechanics, pp. 227-232; Oomens et al., 1987. Journal of Biomechanics 20(9), 877-885] on the skin tissue of an individual's forearm. These measurements show an increase in the normal contact force as a function of the indentation depth. The interpretation of such results usually requires a long and tedious phenomenological study. We propose a new method to determine the mechanical parameters which control the response of skin tissue. This method is threefold: experimental, numerical, and comparative. It consists combining experimental results with a numerical finite elements model in order to find out the required parameters. This process uses a scheme of extended Kalman filters (EKF) [Gu et al., 2003. Materials Science and Engineering A345, 223-233; Nakamura et al., 2000. Acta Mater 48, 4293-4306; Leustean and Rosu, 2003. Certifying Kalman filters. RIACS Technical Report 03.02, 27pp. http://gureni.cs.uiuc.edu/~grosu/download/luta + leo.pdf; Welch and Bishop, An introduction to Kalman filter, University of North Carolina at Chapel Hill, 16p. http://www.cs.unc.edu/~welch/kalman/]. The first results presented in this study correspond to a simplified numerical modeling of the global system. The skin is assumed to be a semi-infinite layer with an isotropic linear elastic mechanical behavior [Zhang et al., 1994. Proceedings of

  5. Frequency and temperature dependence of skin bioimpedance during a contralateral cold test.

    PubMed

    Podtaev, S; Nikolaev, D; Samartsev, V; Gavrilov, V; Tsiberkin, K

    2015-03-01

    A study of the α- and β-dispersion of skin bioimpedance dependence on temperature and micro-hemodynamics is presented. The vascular tone changes during the cold test are verified by the wavelet-analysis of skin temperature signals obtained simultaneously with impedance measurements. Thirty three normal healthy subjects of 28  ±  7 years old were entered into the study. The tetra-polar electrode system was used to record the resistance and reactance; measurements were carried out at 67 frequencies, in a frequency range from 2 Hz to 50 kHz. It has been found that the impedance decreases with vasodilation and increases with vasoconstriction. The high values of correlation among thermal oscillation amplitudes and Nyquist diagram parameters prove the impedance dependence on blood flow in three frequency bands corresponding to the myogenic, neurogenic and endothelial vascular tone regulation mechanisms. Using an equivalent RC circuit, we obtained the changes in the Nyquist diagram matching the experimental data. The proposed descriptive α-dispersion model can be used to study mechanisms responsible for intercellular interaction. PMID:25690397

  6. Positive skin prick tests of immediate type in non-allergic children.

    PubMed

    Cserháti, E; Kiss, A G; Mezei, G; Kelemen, J; Puskás, J

    1983-01-01

    Prick tests with twenty different Beneard antigens were performed in 300 children aged 2-16 years, all having a negative individual and familial history for allergic disease. At least one positive result was obtained in 64% of the children and among the 6000 tests a total of 727 were positive. Of the positive tests 93% were + or ++, 7% were +++ or ++++. No relationship was found between age and the incidence of positive skin tests. Mild reactions against more than one antigen in the same individual were quite frequent, pronounced reactions (+++ or ++++) against more than one antigen were exceptional. The incidence of mild reactions was found to be independent of the gender; strong reactions occurred in girls twice as often as in boys. The highest incidence of positive reactions was observed with house-dust mite, pollens, hay and straw dust, and canine and feline hairs. The diagnostic value of mild positivity is slight but pronounced positivity, especially against more than one antigen, must carefully be considered and in any case followed by a bronchial provocation test. PMID:6639791

  7. Development and preliminary testing of a standardized method for quantifying excess water in over-hydrated skin using evaporimetry.

    PubMed

    Fader, M; Clark-O'Neill, S R; Wong, W K R; Runeman, B; Farbrot, A; Cottenden, A M

    2011-03-01

    Although evaporimetry (the measurement of water vapour flux density from the skin) has often been used to study the impact on skin hydration of using products such as baby diapers and incontinence pads, it is difficult to interpret results and to compare data from different studies because of the diversity of unvalidated methodologies used. The aim of this work was to develop a robust methodology for measuring the excess water in over-hydrated skin and test it on volar forearm and hip skin which had been occluded with saline soaked patches. Three repeat measurements were made on the volar forearm and the hip of five young (31-44 years) and six older (67-85 years) women and moderately good within-subject repeatability was found for both skin sites for both subject groups. Measurements taken from the hip were significantly higher (P = 0.001) than those from the arm and had larger coefficients of variation (3.5-22.1%) compared to arms (3.0-14.0%). There were no significant differences between young and older skin, implying that women for future studies could be recruited without regard to age. This is the first time that a robust evaporimetric methodology for quantifying excess water in over-hydrated skin has been described and validated, and it will form a solid basis for future work. PMID:21285481

  8. Evaluation of Human Semenogelin Membrane Strip Test for Species Cross-reactivity in Dogs.

    PubMed

    Stern, A W; Lanka, S

    2016-09-01

    Semenogelins are proteins originating in the seminal vesicle and are useful markers for the presumptive identification of human semen. Detection of semenogelin can be done with a commercially available membrane test. In this study, a commercially available membrane test for human semenogelin proteins was used to assess for cross-reactivity in dog bodily fluids to allow for the potential utilization for detection of human semen in dog bodily fluids. The authors analyzed canine semen and other bodily fluids, including urine, saliva, vaginal secretions, fecal material, and blood. They also examined the distribution of human semenogelin I transcripts in the canine testis, prostate, and several bodily fluids by reverse transcription polymerase chain reaction. No cross-reactivity was observed in the canine bodily fluids tested except for a single rectal swab, which was negative on a second test. Further testing should be done to validate the use of this kit for screening samples from dogs suspected to have been victims of sexual abuse. PMID:26574559

  9. Concurrent conservative and reactive tracer tests in a stream undergoing hyporheic exchange

    NASA Astrophysics Data System (ADS)

    Lemke, Dennis; Liao, Zijie; WöHling, Thomas; Osenbrück, Karsten; Cirpka, Olaf A.

    2013-05-01

    Knowledge about the strength and travel times of hyporheic exchange is vital to predict reactive transport and biogeochemical cycling in streams. In this study, we outline how to perform and analyze stream tracer tests using pulse injections of fluorescein as conservative and resazurin as reactive tracer, which is selectively transformed to resorufin when exposed to metabolically active zones, presumably located in the hyporheic zone. We present steps of preliminary data analysis and apply a conceptually simple mathematical model of the tracer tests to separate effects of in-stream transport from hyporheic exchange processes. To overcome the dependence of common parameter estimation schemes on the initial guess, we derive posterior parameter probability density functions using an adaptive Markov chain Monte Carlo scheme. By this, we can identify maximum-likelihood parameter values of in-stream transport, strength of hyporheic exchange, distribution of hyporheic travel times as well as sorption and reactivity coefficients of the hyporheic zone. We demonstrate the approach by a tracer experiment at River Goldersbach in southern Germany (60 L/s discharge). In-stream breakthrough curves were recorded with online fluorometers and jointly fitted to simulations of a one-dimensional reactive transport model assuming an exponential hyporheic travel-time distribution. The findings show that the additional analysis of resazurin not only improved the physical basis of the modeling, but was crucial to differentiate between surface transport and hyporheic transient storage of stream solutes. Parameter uncertainties were usually small and could not explain parameter variability between adjacent monitoring stations. The latter as well as a systematic underestimation of the tailing are due to structural errors of the model, particularly the exponential hyporheic travel-time distribution. Mean hyporheic travel times were in the range of 12 min, suggesting that small streambed

  10. Practical applications of genomics research for treatment of aging skin.

    PubMed

    Kaczvinsky, Joseph R; Grimes, Pearl E

    2009-07-01

    Skin aging integrates the impact of extrinsic skin insults (e.g., ultraviolet [UV] light, etc.) with chronological, genetically programmed decreases in cellular function. A genomic study of aged skin highlighted the mechanistic importance of skin barrier function, exfoliation, control of reactive oxygen species and maintenance of extracellular matrix to the aging process. A set of topical products designed to address these mechanistic themes was developed and clinically tested. The individual products improved skin barrier function, hydration and skin turnover, as well as the smoothness and depth of periorbital wrinkles. Treatment with a regimen of these products improved the appearance of facial wrinkles after eight weeks. Changes in treated subjects' stratum corneum protein biomarker levels were consistent with the mechanistic pathways identified in the genomic work. Thus, leveraging a genomic understanding of skin aging led to the development of a clinically efficacious, aesthetically pleasing cosmetic regimen that improved the appearance of aged skin. PMID:19623780

  11. Assessing skin sensitization hazard in mice and men using non-animal test methods.

    PubMed

    Urbisch, Daniel; Mehling, Annette; Guth, Katharina; Ramirez, Tzutzuy; Honarvar, Naveed; Kolle, Susanne; Landsiedel, Robert; Jaworska, Joanna; Kern, Petra S; Gerberick, Frank; Natsch, Andreas; Emter, Roger; Ashikaga, Takao; Miyazawa, Masaaki; Sakaguchi, Hitoshi

    2015-03-01

    Sensitization, the prerequisite event in the development of allergic contact dermatitis, is a key parameter in both hazard and risk assessments. The pathways involved have recently been formally described in the OECD adverse outcome pathway (AOP) for skin sensitization. One single non-animal test method will not be sufficient to fully address this AOP and in many cases the use of a battery of tests will be necessary. A number of methods are now fully developed and validated. In order to facilitate acceptance of these methods by both the regulatory and scientific communities, results of the single test methods (DPRA, KeratinoSens, LuSens, h-CLAT, (m)MUSST) as well for a the simple '2 out of 3' ITS for 213 substances have been compiled and qualitatively compared to both animal and human data. The dataset was also used to define different mechanistic domains by probable protein-binding mechanisms. In general, the non-animal test methods exhibited good predictivities when compared to local lymph node assay (LLNA) data and even better predictivities when compared to human data. The '2 out of 3' prediction model achieved accuracies of 90% or 79% when compared to human or LLNA data, respectively and thereby even slightly exceeded that of the LLNA. PMID:25541156

  12. Tuberculin Skin Tests versus Interferon-Gamma Release Assays in Tuberculosis Screening among Immigrant Visa Applicants

    PubMed Central

    Chuke, Stella O.; Yen, Nguyen Thi Ngoc; Laserson, Kayla F.; Phuoc, Nguyen Huu; Trinh, Nguyen An; Nhung, Duong Thi Cam; Mai, Vo Thi Chi; Qui, An Dang; Hai, Hoang Hoa; Loan, Le Thien Huong; Jones, Warren G.; Whitworth, William C.; Shah, J. Jina; Painter, John A.; Mazurek, Gerald H.; Maloney, Susan A.

    2014-01-01

    Objective. Use of tuberculin skin tests (TSTs) and interferon gamma release assays (IGRAs) as part of tuberculosis (TB) screening among immigrants from high TB-burden countries has not been fully evaluated. Methods. Prevalence of Mycobacterium tuberculosis infection (MTBI) based on TST, or the QuantiFERON-TB Gold test (QFT-G), was determined among immigrant applicants in Vietnam bound for the United States (US); factors associated with test results and discordance were assessed; predictive values of TST and QFT-G for identifying chest radiographs (CXRs) consistent with TB were calculated. Results. Of 1,246 immigrant visa applicants studied, 57.9% were TST positive, 28.3% were QFT-G positive, and test agreement was 59.4%. Increasing age was associated with positive TST results, positive QFT-G results, TST-positive but QFT-G-negative discordance, and abnormal CXRs consistent with TB. Positive predictive values of TST and QFT-G for an abnormal CXR were 25.9% and 25.6%, respectively. Conclusion. The estimated prevalence of MTBI among US-bound visa applicants in Vietnam based on TST was twice that based on QFT-G, and 14 times higher than a TST-based estimate of MTBI prevalence reported for the general US population in 2000. QFT-G was not better than TST at predicting abnormal CXRs consistent with TB. PMID:24738031

  13. Testing of an Integrated Reactor Core Simulator and Power Conversion System with Simulated Reactivity Feedback

    NASA Technical Reports Server (NTRS)

    Bragg-Sitton, Shannon M.; Hervol, David S.; Godfroy, Thomas J.

    2010-01-01

    A Direct Drive Gas-Cooled (DDG) reactor core simulator has been coupled to a Brayton Power Conversion Unit (BPCU) for integrated system testing at NASA Glenn Research Center (GRC) in Cleveland, Ohio. This is a closed-cycle system that incorporates an electrically heated reactor core module, turboalternator, recuperator, and gas cooler. Nuclear fuel elements in the gas-cooled reactor design are replaced with electric resistance heaters to simulate the heat from nuclear fuel in the corresponding fast spectrum nuclear reactor. The thermodynamic transient behavior of the integrated system was the focus of this test series. In order to better mimic the integrated response of the nuclear-fueled system, a simulated reactivity feedback control loop was implemented. Core power was controlled by a point kinetics model in which the reactivity feedback was based on core temperature measurements; the neutron generation time and the temperature feedback coefficient are provided as model inputs. These dynamic system response tests demonstrate the overall capability of a non-nuclear test facility in assessing system integration issues and characterizing integrated system response times and response characteristics.

  14. Testing of an Integrated Reactor Core Simulator and Power Conversion System with Simulated Reactivity Feedback

    NASA Technical Reports Server (NTRS)

    Bragg-Sitton, Shannon M.; Hervol, David S.; Godfroy, Thomas J.

    2009-01-01

    A Direct Drive Gas-Cooled (DDG) reactor core simulator has been coupled to a Brayton Power Conversion Unit (BPCU) for integrated system testing at NASA Glenn Research Center (GRC) in Cleveland, OH. This is a closed-cycle system that incorporates an electrically heated reactor core module, turbo alternator, recuperator, and gas cooler. Nuclear fuel elements in the gas-cooled reactor design are replaced with electric resistance heaters to simulate the heat from nuclear fuel in the corresponding fast spectrum nuclear reactor. The thermodynamic transient behavior of the integrated system was the focus of this test series. In order to better mimic the integrated response of the nuclear-fueled system, a simulated reactivity feedback control loop was implemented. Core power was controlled by a point kinetics model in which the reactivity feedback was based on core temperature measurements; the neutron generation time and the temperature feedback coefficient are provided as model inputs. These dynamic system response tests demonstrate the overall capability of a non-nuclear test facility in assessing system integration issues and characterizing integrated system response times and response characteristics.

  15. Constructing Human Skin Equivalents on Porcine Acellular Peritoneum Extracellular Matrix for In Vitro Irritation Testing.

    PubMed

    Tsai, Pei-Chin; Zhang, Zheng; Florek, Charles; Michniak-Kohn, Bozena B

    2016-01-01

    The irritancy of topical products has to be investigated to ensure the safety and compliance. Although several reconstructed human epidermal models have been adopted by the Organization for Economic Cooperation and Development (OECD) to replace in vivo animal irritation testing, these models are based on a single cell type and lack dermal components, which may be insufficient to reflect all of the components of irritation. In our study, we investigated the use of acellular porcine peritoneum extracellular matrix as a substrate to construct full-thickness human skin equivalents (HSEs) for use as irritation screening tool. The acellular peritoneum matrix (APM) exhibited excellent skin cell attachment (>80%) and proliferation for human dermal fibroblasts (HDF) and immortalized human keratinocytes (HaCaT). APM-HSEs based on coculture of HDF and HaCaT were prepared. Increased HDF seeding density up to 5 × 10(4)/cm(2) resulted in APM-HSEs with a thicker and more organized epidermis. The epidermis of APM-HSEs expressed keratin 15, a keratinocyte proliferation marker, and involucrin, a differentiation marker, respectively. To assess the use of APM-HSEs for irritation testing, six proficiency chemicals, including three nonirritants (phosphate-buffered saline, polyethylene glycol 400, and isopropanol) and three irritants (1-bromohexane, heptanol, and sodium dodecyl sulfate) were applied. The APM-HSEs were able to discriminate nonirritants from irritants based on the viability. Levels of cytokines (interleukin [IL]-1α, IL-1ra, IL-6, IL-8, and granulocyte macrophage colony-stimulating factor [GM-CSF]) in these treatment groups further assisted the irritancy ranking. In conclusion, we have developed partially differentiated full-thickness APM-HSEs based on acellular porcine peritoneum matrix, and these APM-HSEs demonstrated utility as an in vitro irritation screening tool. PMID:26415037

  16. Rat epidermal keratinocyte organotypic culture (ROC) as a model for chemically induced skin irritation testing

    SciTech Connect

    Pappinen, Sari . E-mail: sari.pappinen@uku.fi; Pasonen-Seppaenen, Sanna; Suhonen, Marjukka; Tammi, Raija; Urtti, Arto

    2005-11-01

    The potential of rat epidermal keratinocyte (REK) organotypic culture (ROC) with proper stratum corneum barrier as a model for screening skin irritants was evaluated. The test chemicals were selected from ECETOC database (1995) and the observed in vitro irritation potential was compared to ECETOC in vivo primary irritation index (PII), to EU risk phrases, and to the harmonized OECD criteria. Chemicals were applied onto the stratum corneum surface of ROC for 30 min and samples were taken from the underlying medium at 4 and 8 h after exposure. Cell membrane integrity (determined by LDH assay) and pro-inflammatory effect (determined by IL-1{alpha} release) were verified at both time points and correlated to PII values. The best correlation (R {sup 2} = 0.831) was seen with LDH leakage test. Based on obtained data, chemicals were classified according to criteria defined by EU and OECD. From 12 chemicals, only two were incorrectly classified according to OECD criteria when using LDH leakage and IL-1{alpha} release as irritation markers. At the end of experiment, chemical-treated ROC cultures were fixed and histological changes were assessed. Typical signs for irritation were lightly stained cytoplasm, condensed nuclei, cellular vacuolization, eosinophilic cytoplasms, and blebbing. These irritation effects of chemicals were graded visually into four classes (A-D). The extent of morphological perturbations of the cultures mostly correlated with PII. The present results indicate the validity of the ROC model in predicting skin irritation potential of chemicals and show that the use of set of irritation markers with different mechanistic responses gives more information on irritation than if only one marker was used.

  17. Chemical Reactivity Testing for the National Spent Nuclear Fuel Program. Quality Assurance Project Plan

    SciTech Connect

    Newsom, H.C.

    1999-01-24

    This quality assurance project plan (QAPjP) summarizes requirements used by Lockheed Martin Energy Systems, Incorporated (LMES) Development Division at Y-12 for conducting chemical reactivity testing of Department of Energy (DOE) owned spent nuclear fuel, sponsored by the National Spent Nuclear Fuel Program (NSNFP). The requirements are based on the NSNFP Statement of Work PRO-007 (Statement of Work for Laboratory Determination of Uranium Hydride Oxidation Reaction Kinetics.) This QAPjP will utilize the quality assurance program at Y-12, QA-101PD, revision 1, and existing implementing procedures for the most part in meeting the NSNFP Statement of Work PRO-007 requirements, exceptions will be noted.

  18. Utilization of the QuantiFERON-TB Gold Test in a Two-Step Process with the Tuberculin Skin Test To Evaluate Health Care Workers for Latent Tuberculosis▿

    PubMed Central

    Abdalhamid, Baha; Hinrichs, Steven H.; Garrett, Jodi L.; O'Neill, Jean M.; Hansen-Cain, Kristine M.; Armbrust, Amy A.; Iwen, Peter C.

    2010-01-01

    A cost analysis of combining a tuberculin skin test (TST) and the QuantiFERON-TB Gold test (QFT-GT) to detect latent tuberculosis in newly hired health care workers was performed. An approximately 50% reduction in the cost of additional care was realized when workers with positive TST results were subsequently screened using the QFT-GT. PMID:20573876

  19. Responsive corneosurfametry following in vivo skin preconditioning.

    PubMed

    Uhoda, E; Goffin, V; Pierard, G E

    2003-12-01

    Skin is subjected to many environmental threats, some of which altering the structure and function of the stratum corneum. Among them, surfactants are recognized factors that may influence irritant contact dermatitis. The present study was conducted to compare the variations in skin capacitance and corneosurfametry (CSM) reactivity before and after skin exposure to repeated subclinical injuries by 2 hand dishwashing liquids. A forearm immersion test was performed on 30 healthy volunteers. 2 daily soak sessions were performed for 5 days. At inclusion and the day following the last soak session, skin capacitance was measured and cyanoacrylate skin-surface strippings were harvested. The latter specimens were used for the ex vivo microwave CSM. Both types of assessments clearly differentiated the 2 hand dishwashing liquids. The forearm immersion test allowed the discriminant sensitivity of CSM to increase. Intact skin capacitance did not predict CSM data. By contrast, a significant correlation was found between the post-test conductance and the corresponding CSM data. In conclusion, a forearm immersion test under realistic conditions can discriminate the irritation potential between surfactant-based products by measuring skin conductance and performing CSM. In vivo skin preconditioning by surfactants increases CSM sensitivity to the same surfactants. PMID:15025702

  20. Autologous serum skin test in chronic idiopathic urticaria: prevalence, correlation and clinical implications.

    PubMed

    Kulthanan, Kanokvalai; Jiamton, Sukhum; Gorvanich, Taniya; Pinkaew, Sumruay

    2006-12-01

    Some cases of chronic idiopathic urticaria (CIU) have histamine-releasing IgG autoantibodies in their blood. This disease subgroup is called "autoimmune urticaria". To date, the autologous serum skin test (ASST) is the best in vivo clinical test for the detection of basophil histamine-releasing activity in vitro. This study aimed to find the prevalence of ASST positive cases in Thai patients with CIU, to identify factors related to the positivity of ASST and to find the clinical implications of ASST in CIU. A retrospective study was performed among 85 CIU patients who attended the Urticaria Clinic at the Department of Dermatology, Siriraj Hospital and were willing to perform ASST, from January 2002 to December 2003. Twenty-one (24.7%) patients had a positive ASST. There was no significant difference between patients with positive ASST and negative ASST as to the severity of the disease (wheal numbers, wheal size, itching scores and the extent of body involvement) as well as the duration of the disease. PMID:17348242

  1. Skin Prick Test Analysis in Allergic Rhinitis Patients: A Preliminary Study in Abuja, Nigeria

    PubMed Central

    Ibekwe, T. S.

    2016-01-01

    Allergic rhinitis (AR) is prevalent in Nigeria, though little information exists on the allergen. We assessed the clinical features of AR patients in our environment based on the allergic rhinitis impact on asthma (ARIA) classification. Only patients with positive skin prick test (SPT) were recruited. Seventy-four patients participated in the study. AR and asthma comorbidity were observed in 13.5%. The proportion of “sneezers-runners” was higher than “blockers” with significantly more “sneezers-runners” having persistent AR (P = 0.007). No relationship was established between these predominant symptoms and the aeroallergens used in this study. Intermittent mild and moderate/severe AR were evident in 13.5% and 31.1%, while persistent mild and moderate/severe were seen in 20.3% and 35.1%, respectively. House dust mites allergen yielded the highest number of positive responses (22.6%) followed by tree pollen (16.8%). No relationship was observed between the allergens tested and AR severity. Majority of patients were oligosensitive (33.8%) and polysensitive (35.1%) and were not significantly associated with AR severity (P = 0.07). Most AR patients presenting for treatment in Abuja, Nigeria, had moderate-severe persistent AR and showed similar SPT sensitization pattern with countries having similar climatic conditions. Sensitization patterns were not related to ARIA classification or predominant AR symptoms. PMID:27247577

  2. Cytotoxicity testing of silver-containing burn treatments using primary and immortal skin cells.

    PubMed

    Boonkaew, Benjawan; Kempf, Margit; Kimble, Roy; Cuttle, Leila

    2014-12-01

    A novel burn wound hydrogel dressing has been previously developed which is composed of 2-acrylamido-2-methylpropane sulfonic acid sodium salt with silver nanoparticles (silver AMPS). This study compared the cytotoxicity of this dressing to the commercially available silver products; Acticoat™, PolyMem Silver(®) and Flamazine™ cream. Human keratinocytes (HaCaT and primary HEK) and normal human fibroblasts (NHF) were exposed to dressings incubated on Nunc™ polycarbonate inserts for 24, 48 and 72h. Four different cytotoxicity assays were performed including; Trypan Blue cell count, MTT, Celltiter-Blue™ and Toluidine Blue surface area assays. The results were expressed as relative cell viability compared to an untreated control. The cytotoxic effects of Acticoat™ and Flamazine™ cream were dependent on exposure time and cell type. After 24h exposure, Acticoat™ and Flamazine™ cream were toxic to all tested cell lines. Surprisingly, HaCaTs treated with Acticoat™ and Flamazine™ had an improved ability to survive at 48 and 72h while HEKs and NHFs had no improvement in survival with any treatment. The novel silver hydrogel and PolyMem Silver(®) showed low cytotoxicity to all tested cell lines at every time interval and these results support the possibility of using the novel silver hydrogel as a burn wound dressing. Researchers who rely on HaCaT cells as an accurate keratinocyte model should be aware that they can respond differently to primary skin cells. PMID:24767717

  3. [Which tuberculin skin test hyperreactive child should be treated with -our experience].

    PubMed

    Pavić, Ivan; Hojsak, Iva; Žmak, Ljiljana; Tješić-Drinković, Dorian; Bogović, Jasna Čepin; Katalinić-Janković, Vera

    2015-01-01

    Since persons with latent tuberculosis infection (LTBI) represent a huge reservoir of potential tuberculosis (TB) disease, accurate diagnosis and treatment of LTBI is essential for TB control and eradication. The aim was to assess the diagnostic value of determination of interferon-gamma release assay in school children with hyperreactive tuberculin skin test (TST) reaction. A total of 120 BCG-vaccinated children were investigated due to a hyperreactive TST results. The QuantiFERON-TB Gold In-Tube test (QFT-GIT) was performed. Fifteen children (12.5%) had positive QFT-GIT and 105 (87.5%) children had negative QFT-GIT. There was no statistically significant difference in TST reaction (21.5 mm u QFT+ vs. 20.9 mm u QFT-group, p=0.458). The children with positive QFT-GIT had a statistically higher level of interferon-gamma (IFN-γ) than children with negative QFT-GIT. There were no statistically significant differences in concentrations of IFN-y either basic or upon stimulation with mitogen phytohemagglutinin. After isoniazid prophylaxis QFT-GIT remained positive in two children (p=0.019). In a difficult procedure for diagnosing LTBI in BCG-vaccinated children determination of IFN-γ could be the key factor in making decision whether to use preventive therapy or not. PMID:26502676

  4. Skin turgor

    MedlinePlus

    Doughy skin; Poor skin turgor; Good skin turgor; Decreased skin turgor ... Call your health care provider if: Poor skin turgor occurs with vomiting, diarrhea, or fever. The skin is very slow to return to normal, or the skin "tents" up ...

  5. Sensitization to cereals and peanut evidenced by skin prick test and specific IgE in food-tolerant, grass pollen allergic patients

    PubMed Central

    2011-01-01

    Background The botanical relation between grass and cereal grains may be relevant when diagnosing food allergy to cereals. The aim was to investigate the diagnostic specificity of skin prick test (SPT) and specific immunoglobulin E (sIgE) tests to cereals and peanut in grass pollen allergic subjects without history of, and clinically reactions to foods botanically related to grass. Methods 70 subjects (41 females; mean age 32 years) and 20 healthy controls (13 females; mean age 24 years) were tested by open food challenge (OFC) with cereals and peanut. SPT and sIgE both with Immulite® (Siemens) and ImmunoCAP® (Phadia) to grass and birch pollen, cereals, peanut and bromelain were performed. Results Of the 65 OFC-negative subjects 29-46% (SPT, depending on cut-off), 20% (Immulite) and 38% (ImmunoCAP) had positive results to one or more of the foods tested. Controls were negative in all tests. Cross-reactive carbohydrate determinants (CCD) as evidenced by reaction to bromelain could explain only a minority of the measured IgE-sensitizations. Conclusion Grass pollen allergic patients with documented food tolerance to cereals and peanut may express significant sensitization. False-positive cereal or peanut allergy diagnoses may be a quantitatively important problem both in routine clinical work and epidemiological studies. PMID:22409998

  6. Behavioural responses in a net restraint test predict interrenal reactivity in Arctic charr Salvelinus alpinus.

    PubMed

    Magnhagen, C; Backström, T; Øverli, Ø; Winberg, S; Nilsson, J; Vindas, M A; Brännäs, E

    2015-07-01

    In this study, a 1 min net restraint test was evaluated as a method to predict stress-coping style in Arctic charr Salvelinus alpinus, by investigating the relationship between behaviour during the test and levels of plasma cortisol sampled after 30 min confinement. In two separate groups of S. alpinus, general linearized model revealed significant correlations between cortisol levels and principal component scores extracted from principal component analysis, combining measures of activity in the tests. With the use of glmulti, the model selection ruled out any effects of size, sex and order of capture on interrenal reactivity. In general, S. alpinus that were more active in the net restraint test also had low levels of circulating cortisol, suggesting a proactive coping style. The results from two repeated runs were not correlated, but both runs, performed eight days apart, show a negative correlation between post-stress cortisol level and activity in the net. The lack of consistency could be explained by different treatments before each run and individual differences in behavioural plasticity. The net restraint test is thus predictive of stress-coping style in S. alpinus, and has the benefit of being less time-consuming than the commonly used confinement stress test. PMID:25919345

  7. REACTIVITY INITIATED ACCIDENT TEST SERIES TEST RIA 1-4 EXPERIMENT PREDICTIONS

    SciTech Connect

    Fukuda, S. K.; Martinson, Z. R.

    1980-02-01

    The results of the pretest analyses for Test RIA 1-4 are presented. Test RIA 1-4 consists of a 3x3 array of previously irradiated MAP! fuel rods. The rods have 5.7% enriched UO{sub 2} fuel in zircaloy-4 cladding with an average burnup of 5300 MWd/t. The objective for Test RIA 1-4 is to provide information regarding loss-of-coolable fuel rod geometry following RIA event for a radial-average peak fuel enthalpy equivalent to the present licensing criteria of 1172 J/g (280 cal/g UO{sub 2}). Radial averaged peak fuel enthalpies of 1172 J/g (280 cal/g) 1077 J/g {257 cal/g), and 978 J/g (234 cal/g) for the corner, side, and center fuel rods, respectively, are planned to be achieved during a 2.7 ms reactor period power burst. The results of the FRAP-T5 analyses indicate that all nine rods will fail within 26 ms from the start of the power burst due to pellet-cladding mechanical interaction. All of the rods will undergo partial fuel melting. All rods will operate under extended film boiling (>30 sec) conditions and about 70% of the cladding length is expected to be molten. Approximately 15% of the cladding thickness will be oxided. Fuel swelling due to fission gas release and melting combined with fuel and cladding fragmentation, will probably produce a complete coolant flow blockage within the flow shroud.

  8. New strategies for development of a safe and effective skin decontamination system. Annual report

    SciTech Connect

    Langenmayr, E.J.

    1988-11-09

    Under previous contract to USAMRDC, Rohm and Haas Company has demonstrated the concept of using small particle size, insoluble reactive sorptive resins as the basis for a safe and effective skin decontamination kit (SDK). The objective of the current contract is to identify new resins for skin decontamination which show improved reactivity, sorptivity, and retentivity for CW agents over those resins evaluated in previous contracts yet which remain safe for use on human skin. Reactive and sorbent resins were evaluated using several in vitro methods which measured reactivity, reactive capacity, retentivity and wettability. Chloroethylisobutyl sulfide (CIS) was used as a mustard simulant and diisopropylflurophosphate (DFP) was used as a G agent simulant. Nineteen sorbent resins and sixty-five reactive resins were evaluated. Of the sorbent resins evaluated, the carbonaceous sorbents and the macronet sorbents were found to be clearly superior to the other sorbent resins tested with respect to performance in the in vitro tests. Reactive resins containing hydroxide ion performed, as a group, better than reactive resins containing other reactive functionality in all of the in vitro tests. Resins with the highest reactivity toward simulants were those which contained hydroxide ion as nucleophile. Several other polymer-bound nucleophiles were highly reactive toward the G agent simulant DFP but only hydroxide ion had high reactivity against the mustard simulant CIS.

  9. A few days of social separation affects yearling horses' response to emotional reactivity tests and enhances learning performance.

    PubMed

    Lansade, Léa; Neveux, Claire; Levy, Frédéric

    2012-09-01

    Learning performance is influenced by emotional reactivity, low reactivity being generally beneficial. Previous experiments show that emotional reactivity can be modified after a period of social isolation. We hypothesized that eleven days of isolation would affect yearlings' emotional reactivity and improve their learning abilities. Twenty-five yearlings were divided into two groups: 12 were continuously isolated for 11 days (isolated) and 13 stayed together (control). During the period of isolation, all yearlings underwent two learning tasks: a habituation procedure in which a novel object was presented for 120 s every day, either when the horse was alone (isolated) or with conspecifics (control); an instrumental learning task in which the yearling had to walk forwards or backwards to obtain a food reward. At the end of the isolation period, animals performed tests to assess aspects of emotional reactivity: reactivity to novelty, to humans, to social separation, to suddenness and to sensory stimuli. Results showed that isolated yearlings habituated more to the novel object than controls and performed better in the instrumental task. Moreover, they were less reactive to novelty, to social separation and to suddenness than controls. Overall, these data suggest that the better performance of isolated yearlings could be explained by a decrease in their emotional reactivity. This article is part of a Special Issue entitled: insert SI title. PMID:22705773

  10. Application of a Virtual Reactivity Feedback Control Loop in Non-Nuclear Testing of a Fast Spectrum Reactor

    NASA Technical Reports Server (NTRS)

    Bragg-Sitton, Shannon M.; Forsbacka, Matthew

    2004-01-01

    For a compact, fast-spectrum reactor, reactivity feedback is dominated by core deformation at elevated temperature. Given the use of accurate deformation measurement techniques, it is possible to simulate nuclear feedback in non-nuclear electrically heated reactor tests. Implementation of simulated reactivity feedback in response to measured deflection is being tested at the NASA Marshall Space Flight Center Early Flight Fission Test Facility (EFF-TF). During tests of the SAFE-100 reactor prototype, core deflection was monitored using a high resolution camera. "virtual" reactivity feedback was accomplished by applying the results of Monte Carlo calculations (MCNPX) to core deflection measurements; the computational analysis was used to establish the reactivity worth of van'ous core deformations. The power delivered to the SAFE-100 prototype was then dusted accordingly via kinetics calculations, The work presented in this paper will demonstrate virtual reactivity feedback as core power was increased from 1 kilowatt(sub t), to 10 kilowatts(sub t), held approximately constant at 10 kilowatts (sub t), and then allowed to decrease based on the negative thermal reactivity coefficient.

  11. Reliability of self-assessed reading of skin tests: a possible approach in research and clinical practice?

    PubMed

    Falk, Magnus; Anderson, Chris

    2010-01-01

    In the investigation and management of skin disease, various testing protocols are of importance. The extent to which clinical judgments and decisions on therapy are supported by the performance of such testing can be affected negatively by the lack of time and resources for the performance of tests. In the present study, the possibility of utilizing self-reporting by subjects is investigated. Determination of irritation threshold for sodium lauryl sulphate (SLS) and minimal erythema dose for ultraviolet B were chosen as suitable self-reading protocols. Test reading by 26 subjects instructed in "present" or "absent" reporting of test reactions were compared to trained observer reading. Absolute agreement was found in 76.9 percent of the SLS reactions and in 85 percent of the UVB reactions. Weighted Kappa for the agreement between observations showed values of 0.76 for the SLS reactions and 0.83 for UVB reactions. We conclude that use of the protocols here studied, and other test protocols modified to accommodate a binomial assessment outcome ("+" or "-"), could well lead to an increase in the performance of skin testing. This could be a qualitative advantage for diagnosis and management of skin diseases. Additionally, population studies and even prevention initiatives could be facilitated. PMID:20178700

  12. Proposal of a skin tests based approach for the prevention of recurrent hypersensitivity reactions to iodinated contrast media.

    PubMed

    Della-Torre, E; Berti, A; Yacoub, M R; Guglielmi, B; Tombetti, E; Sabbadini, M G; Voltolini, S; Colombo, G

    2015-05-01

    The purpose of the present work is to evaluate the efficacy of an approach that combines clinical history, skin tests results, and premedication, in preventing recurrent hypersensitivity reactions to iodinated contrast media (ICM). Skin Prick tests, Intradermal tests, and Patch tests were performed in 36 patients with a previous reaction to ICM. All patients underwent a second contrast enhanced radiological procedure with an alternative ICM selected on the basis of the proposed approach. After alternative ICM re-injection, only one patient presented a mild NIR. The proposed algorithm, validated in clinical settings where repeated radiological exams are needed, offers a safe and practical approach for protecting patients from recurrent hypersensitivity reactions to ICM. PMID:25951145

  13. In situ testing of metallic iron nanoparticle mobility and reactivity in a shallow granular aquifer.

    PubMed

    Bennett, Peter; He, Feng; Zhao, Dongye; Aiken, Brian; Feldman, Lester

    2010-07-30

    This paper describes the results of a series of single well push-pull tests conducted to evaluate the in situ transport of carboxymethyl cellulose (CMC) stabilized nanoscale zero-valent iron (ZVI) particles in saturated sediments and their reactivity toward chlorinated ethenes. CMC-stabilized nanoscale ZVI particles were synthesized on site by reducing ferrous ions with borohydride in water in the presence of CMC. Nanoscale ZVI and bimetallic ZVI-Pd nanoparticle suspensions were prepared and injected into depth-discrete aquifer zones during three push-pull tests. The injected nanoparticle suspensions contained a conservative tracer (Br(-)) and were allowed to reside in the aquifer pore space for various time periods prior to recovery by groundwater extraction. The comparison between Br(-) and Fe concentrations in extracted groundwater samples indicated that the CMC-stabilized nanoscale ZVI particles were mobile in the aquifer but appeared to lose mobility with time, likely due to the interactions between particles and aquifer sediments. After 13 h in the aquifer, the nanoscale ZVI particles became essentially immobilized. During the push-pull test with injection of Fe-Pd nanoparticles, ethane concentrations increased from non-detectable to 65 microg/L in extracted groundwater within less than 2 h of reaction time, indicating the rapid abiotic degradation of chlorinated ethenes. The amount of total chlorinated ethene mass destroyed was low presumably because the injected solutions "pushed" the dissolved chlorinated ethenes away from the injection well, without substantial mixing, and because stationary (sorbed) chlorinated ethene mass on the aquifer sediments was low. In situ remediation programs using highly reactive metallic nanoparticles should incorporate delivery methods that maintain high groundwater pore velocities during injection to increase advective transport distances (e.g. groundwater circulation wells). Also, source zones with abundant stationary

  14. Testing for the presence of magnetite in the upper-beak skin of homing pigeons.

    PubMed

    Tian, Lanxiang; Xiao, Bo; Lin, Wei; Zhang, Shuyi; Zhu, Rixiang; Pan, Yongxin

    2007-04-01

    We carried out magnetic and nonmagnetic experiments on fresh, upper-beak skin tissue samples isolated from six pairs of homing pigeons to test whether the tissue contains magnetite particles. Results of (1) room-temperature isothermal remanent magnetization (IRM) acquisition and alternating field (AF) demagnetization, (2) low-temperature demagnetization of saturation IRM acquired at 5 K in a field of 5 tesla (T) (SIRM(5 K)) after zero-field cooled (ZFC) and field cooled (FC) treatments, and (3) cycling of the saturation IRM acquired at 300 K in a field of 5 T (SIRM(300 K)) between 5 and 300 K, indicate the presence of magnetite in the measured samples. A significant loss of SIRM(5 K) below 20 K suggests the dominance of superparamagnetic (SPM) particles. The SIRM acquisition capacity of the female pigeon is stronger than that of the male pigeon in all four measured pairs, suggesting for the first time that the magnetite concentration is probably sex dependent. Light microscopic observation on the histological sections stained with Prussian Blue detected the presence of some tiny, dotted, dark-blue staining Fe3+ aggregates (size 1-4 microm) located directly beneath the subcutis within strands of connective tissue, nearby the rim of the regions full of red nuclei. The results of this study support the idea that homing pigeons may have a magnetite-based receptor, which potentially could be used for sensing the Earth's magnetic field during navigation. PMID:16900396

  15. Sub-categorisation of skin corrosive chemicals by the EpiSkin™ reconstructed human epidermis skin corrosion test method according to UN GHS: revision of OECD Test Guideline 431.

    PubMed

    Alépée, N; Grandidier, M H; Cotovio, J

    2014-03-01

    The EpiSkin™ skin corrosion test method was formally validated and adopted within the context of OECD TG 431 for identifying corrosive and non-corrosive chemicals. The EU Classification, Labelling and Packaging Regulation (EU CLP) system requires the sub-categorisation of corrosive chemicals into the three UN GHS optional subcategories 1A, 1B and 1C. The present study was undertaken to investigate the usefulness of the validated EpiSkin™ test method to identify skin corrosive UN GHS Categories 1A, 1B and 1C using the original and validated prediction model and adapted controls for direct MTT reduction. In total, 85 chemicals selected by the OECD expert group on skin corrosion were tested in three independent runs. The results obtained were highly reproducible both within (>80%) and between (>78%) laboratories when compared with historical data. Moreover the results obtained showed that the EpiSkin™ test method is highly sensitive (99%) and specific (80%) in discriminating corrosive from non-corrosive chemicals and allows reliable and relevant identification of the different skin corrosive UN GHS subcategories, with high accuracies being obtained for both UN GHS Categories 1A (83%) and 1B/1C (76%) chemicals. The overall accuracy of the test method to subcategorise corrosive chemicals into three or two UN GHS subcategories ranged from 75% to 79%. Considering those results, the revised OECD Test Guideline 431 permit the use of EpiSkin™ for subcategorising corrosive chemicals into at least two classes (Category 1A and Category 1B/1C). PMID:24211528

  16. THREE-DIMENSIONAL IGNITION AND GROWTH REACTIVE FLOW MODELING OF PRISM FAILURE TESTS ON PBX 9502

    SciTech Connect

    Garcia, M L; Tarver, C M

    2006-06-20

    The Ignition and Growth reactive flow model for shock initiation and detonation of solid explosives based on triaminotirnitrobenzene (TATB) is applied to three-dimensional detonation wave propagation. The most comprehensive set of three-dimensional detonation wave propagation data is that measured using the trapezoidal prism test. In this test, a PBX 9501 (95% HMX, 2.5% Estane, and 2.5% BDNPA/F) line detonator initiates a detonation wave along the trapezoidal face of a PBX 9502 (95% TATB and 5% Kel-F binder) prism. The failure thickness, which has been shown experimentally to be roughly half of the failure diameter of a long cylindrical charge, is measured after 50 mm of detonation wave propagation by impact with an aluminum witness plate. The effects of confinement impedance on the PBX 9502 failure thickness have been measured using air (unconfined), water, PMMA, magnesium, aluminum, lead, and copper placed in contact with the rectangular faces of the prism parallel to the direction of detonation propagation. These prism test results are modeled using the two-dimensional PBX 9502 Ignition and Growth model parameters determined by calculating failure diameter and tested on recent corner turning experiments. Good agreement between experimentally measured and calculated prism failure thicknesses for unconfined and confined PBX 9502 is reported.

  17. The Lancet Weight Determines Wheal Diameter in Response to Skin Prick Testing with Histamine

    PubMed Central

    Andersen, Hjalte H.; Elberling, Jesper; Arendt-Nielsen, Lars

    2016-01-01

    Background Skin prick test (SPT) is a common test for diagnosing immunoglobulin E-mediated allergies. In clinical routine, technicalities, human errors or patient-related biases, occasionally results in suboptimal diagnosis of sensitization. Objective Although not previously assessed qualitatively, lancet weight is hypothesized to be important when performing SPT to minimize the frequency of false positives, false negatives, and unwanted discomfort. Methods Accurate weight-controlled SPT was performed on the volar forearms and backs of 20 healthy subjects. Four predetermined lancet weights were applied (25 g, 85 g, 135 g and 265 g) using two positive control histamine solutions (1 mg/mL and 10 mg/mL) and one negative control (saline). A total of 400 SPTs were conducted. The outcome parameters were: wheal size, neurogenic inflammation (measured by superficial blood perfusion), frequency of bleeding, and the lancet provoked pain response. Results The mean wheal diameter increased significantly as higher weights were applied to the SPT lancet, e.g. from 3.2 ± 0.28 mm at 25 g to 5.4 ± 1.7 mm at 265 g (p<0.01). Similarly, the frequency of bleeding, the provoked pain, and the neurogenic inflammatory response increased significantly. At 265 g saline evoked two wheal responses (/160 pricks) below 3 mm. Conclusion and clinical relevance The applied weight of the lancet during the SPT-procedure is an important factor. Higher lancet weights precipitate significantly larger wheal reactions with potential diagnostic implications. This warrants additional research of the optimal lancet weight in relation to SPT-guidelines to improve the specificity and sensitivity of the procedure. PMID:27213613

  18. Clinical relevance is associated with allergen-specific wheal size in skin prick testing

    PubMed Central

    Haahtela, T; Burbach, G J; Bachert, C; Bindslev-Jensen, C; Bonini, S; Bousquet, J; Bousquet-Rouanet, L; Bousquet, P J; Bresciani, M; Bruno, A; Canonica, G W; Darsow, U; Demoly, P; Durham, S R; Fokkens, W J; Giavi, S; Gjomarkaj, M; Gramiccioni, C; Kowalski, M L; Losonczy, G; Orosz, M; Papadopoulos, N G; Stingl, G; Todo-Bom, A; von Mutius, E; Köhli, A; Wöhrl, S; Järvenpää, S; Kautiainen, H; Petman, L; Selroos, O; Zuberbier, T; Heinzerling, L M

    2014-01-01

    Background Within a large prospective study, the Global Asthma and Allergy European Network (GA2LEN) has collected skin prick test (SPT) data throughout Europe to make recommendations for SPT in clinical settings. Objective To improve clinical interpretation of SPT results for inhalant allergens by providing quantitative decision points. Methods The GA2LEN SPT study with 3068 valid data sets was used to investigate the relationship between SPT results and patient-reported clinical relevance for each of the 18 inhalant allergens as well as SPT wheal size and physician-diagnosed allergy (rhinitis, asthma, atopic dermatitis, food allergy). The effects of age, gender, and geographical area on SPT results were assessed. For each allergen, the wheal size in mm with an 80% positive predictive value (PPV) for being clinically relevant was calculated. Results Depending on the allergen, from 40% (blatella) to 87–89% (grass, mites) of the positive SPT reactions (wheal size ≥ 3 mm) were associated with patient-reported clinical symptoms when exposed to the respective allergen. The risk of allergic symptoms increased significantly with larger wheal sizes for 17 of the 18 allergens tested. Children with positive SPT reactions had a smaller risk of sensitizations being clinically relevant compared with adults. The 80% PPV varied from 3 to 10 mm depending on the allergen. Conclusion These ‘reading keys’ for 18 inhalant allergens can help interpret SPT results with respect to their clinical significance. A SPT form with the standard allergens including mm decision points for each allergen is offered for clinical use. PMID:24283409

  19. Effect of a microemulsion system on hapten-peptide reactivity studies: examples of hydroxycitronellal and citral, fragrance skin sensitizers, with glutathione.

    PubMed

    Merckel, Fabien; Bernard, Guillaume; Mutschler, Julien; Giménez-Arnau, Elena; Gerberick, G Frank; Lepoittevin, Jean-Pierre

    2010-09-20

    In chemico methods, based on the assessment of hapten reactivity toward peptides, have been proposed as alternative methods for the assessment of the skin sensitizing potential of chemicals. However, even if these approaches seem very promising, a major drawback inherent to most in vitro methods is the poor water solubility of many organic molecules in aqueous media. Thus, semiorganic media based on buffer solutions and organic cosolvents such as ethanol or acetonitrile have been proposed, but a narrow equilibrium should be found between the peptide and chemical solubilities. Microemulsions have been shown to be very valuable when reacting a lipophilic organic compound soluble in hydrophobic media with a very hydrophilic organic substance insoluble in most organic solvents. However, the reaction rate between polar and apolar reactants can be influenced, in some cases, by the use of microemulsions. On the basis of NMR experiments, we have compared the reactivity of hydroxycitronellal 1 and citral 2, two weak fragrance sensitizers of major clinical relevance, toward glutathione used as a model nucleophile in a water/acetonitrile 2:1 mixture and in a microemulsion based on chloroform/water/tert-butanol/sodium dodecylsulphate. Hydroxycitronellal and citral were found to react with the thiol group of glutathione to form, in both media, identical adducts, but the observed reaction rates were found to be different. In the case of hydroxycitronellal, the observed reaction rate of glutathione addition on the aldehyde was found to be about three times higher in the microemulsion compared to the classical semiorganic mixture. In the case of citral, the situation was more complex as the Michael addition of glutathione on the conjugated double bond was found to be significantly faster in the classical semiorganic mixture, while the subsequent reaction of a second glutathione molecule on the aldehyde was found to be faster in the microemulsion. This chloroform

  20. Antimicrobial activity of ceftaroline tested against bacterial isolates causing respiratory tract and skin and skin structure infections in US medical centers in 2013.

    PubMed

    Sader, Helio S; Farrell, David J; Mendes, Rodrigo E; Flamm, Robert K; Castanheira, Mariana; Jones, Ronald N

    2015-05-01

    A total of 4533 isolates from community-acquired respiratory tract infections (CARTIs) and 8446 from skin and skin structure infections (SSSIs) were consecutively collected in 149 US medical centers in 2013. Strains were susceptibility tested by broth microdilution method against ceftaroline and numerous comparators. Ceftaroline (MIC(50/90), ≤0.015/0.12 μg/mL) was more potent than ceftriaxone (MIC(50/90), ≤0.06/1 μg/mL) against Streptococcus pneumoniae and highly active against ceftriaxone-nonsusceptible strains (n=201; MIC(90), 0.25 μg/mL). Ceftaroline was also very active against Haemophilus influenzae (MIC(50/90), 0.008/0.015 μg/mL), methicillin-susceptible (MIC(50/90), 0.25/0.25 μg/mL) and methicillin-resistant Staphylococcus aureus (MIC(50/90), 1/1 μg/mL), and β-hemolytic streptococci (highest MIC, 0.03 μg/mL). Ceftaroline exhibited good activity against non-extended-spectrum β-lactamase (ESBL) phenotype isolates of Klebsiella spp. and Escherichia coli (96.7% susceptible and MIC(90) of 0.25 μg/mL for both) but limited activity against ESBL phenotype isolates. In summary, ceftaroline exhibited potent in vitro activity against a large collection of bacterial isolates causing CARTI and SSSI in US medical centers. PMID:25708896

  1. Antimicrobial Activity of the Investigational Pleuromutilin Compound BC-3781 Tested against Gram-Positive Organisms Commonly Associated with Acute Bacterial Skin and Skin Structure Infections

    PubMed Central

    Biedenbach, Douglas J.; Paukner, Susanne; Ivezic-Schoenfeld, Zrinka; Jones, Ronald N.

    2012-01-01

    BC-3781 is a novel semisynthetic pleuromutilin antimicrobial agent developed as an intravenous and oral therapy for acute bacterial skin and skin structure infections (ABSSSI) and respiratory tract infections (RTI). BC-3781 and comparator agents were tested by the broth microdilution method against 1,893 clinical Gram-positive organisms predominantly causing ABSSSI. BC-3781 exhibited potent activity against methicillin-resistant Staphylococcus aureus (MIC50/90, 0.12/0.25 μg/ml), coagulase-negative staphylococci (MIC50/90, 0.06/0.12 μg/ml), β-hemolytic streptococci (MIC50/90, 0.03/0.06 μg/ml), viridans group streptococci (MIC50/90, 0.12/0.5 μg/ml), and Enterococcus faecium (including vancomycin-nonsusceptible strains) (MIC50/90, 0.12/2 μg/ml). Compared with other antibiotics in use for the treatment of ABSSSI, BC-3781 displayed the lowest MICs and only a minimal potential for cross-resistance with other antimicrobial classes. PMID:22232289

  2. Predicting Cross Reactive Immunological Material (CRIM) Status in Pompe Disease Using GAA Mutations: Lessons Learned from 10 Years of Clinical Laboratory Testing Experience

    PubMed Central

    Bali, Deeksha S.; Goldstein, Jennifer L.; Banugaria, Suhrad; Dai, Jian; Mackey, Joanne; Rehder, Catherine; Kishnani, Priya S.

    2012-01-01

    Enzyme replacement therapy (ERT) for Pompe disease using recombinant acid alpha-glucosidase (rhGAA) has resulted in increased survival although the clinical response is variable. Cross Reactive Immunological Material (CRIM)-negative status has been recognized as a poor prognostic factor. CRIM-negative patients make no GAA protein and develop sustained high antibody titers to ERT that render the treatment ineffective. Antibody titers are generally low for the majority of CRIM-positive patients and there is typically a better clinical outcome. Because immunomodulation has been found to be most effective in CRIM-negative patients prior to, or shortly after, initiation of ERT, knowledge of CRIM status is important before ERT is begun. We have analyzed 243 patients with infantile Pompe disease using a Western blot method for determining CRIM status and using cultured skin fibroblasts. Sixty-one out of 243 (25.1%) patients tested from various ethnic backgrounds were found to be CRIM-negative. We then correlated the CRIM results with GAA gene mutations where available (52 CRIM-negative and 88 CRIM-positive patients). We found that, in most cases, CRIM status can be predicted from GAA mutations, potentially circumventing the need for invasive skin biopsy and time wasted in culturing cells in the future. Continued studies in this area will help to increase the power of GAA gene mutations in predicting CRIM status as well as possibly identifying CRIM-positive patients who are at risk for developing high antibody titers. PMID:22252923

  3. Differences between heat-treated raw and commercial peanut extracts by skin testing and immunoblotting

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanut is generally consumed in a heat-treated form, yet the commonly available extracts for diagnostic purposes are derived from raw peanuts. Raw and heat-treated samples were prepared and compared with commercially available peanut extracts regarding SPT reactivity and serum IgE reactivity. Protei...

  4. Chemical reactivity testing for the National Spent Nuclear Fuel Program. Revision 2

    SciTech Connect

    Koester, L.W.

    2000-02-08

    This quality assurance project plan (QAPjP) summarizes requirements used by Lockheed Martin Energy Systems, Incorporated (LMES) Development Division at Y-12 for conducting chemical reactivity testing of Department of Energy (DOE) owned spent nuclear fuel, sponsored by the National Spent Nuclear Fuel Program (NSNFP). The requirements are based on the NSNFP Statement of work PRO-007 (Statement of Work for Laboratory Determination of Uranium Hydride Oxidation Reaction Kinetics.) This QAPjP will utilize the quality assurance program at Y-12, Y60-101PD, Quality Program Description, and existing implementing procedures for the most part in meeting the NSNFP Statement of Work PRO-007 requirements, exceptions will be noted. The project consists of conducting three separate series of related experiments, ''Passivation of Uranium Hydride Powder With Oxygen and Water'', '''Passivation of Uranium Hydride Powder with Surface Characterization'', and ''Electrochemical Measure of Uranium Hydride Corrosion Rate''.

  5. Testing to determine chemical stability, handling characteristics, and reactivity of energetic-fuel mixtures: Final report

    SciTech Connect

    Lackey, M.E.

    1988-04-01

    The US Army generates approximately 2.5 million pounds of waste explosives each year as a result of explosives production and the loading of ordnance. In addition, the US Army currently stores >200,000 tons of obsolete munitions. The current alternative to storage is open-air burning, open-air detonation, or incineration. The US Army Toxic and Hazardous Materials Agency is currently developing methods and procedures for the utilization of energetic materials blended with fuel oil as supplemental fuel in Army industrial combustors. A series of tests were conducted to evaluate the chemical compatibility, reactivity, and handling characteristics of energetic-fuel mixtures. The energetics studied were TNT, RDX, and Composition B. Results indicated that under specific conditions of energetic content, energetic/fuel oil preparation, and system design, energetic/fuel oil mixtures can successfully be used as supplemental fuel in Army industrial combustors. 9 refs., 2 figs., 8 tabs.

  6. Reactivity of anti-glycophorin monoclonal antibodies (Mabs) in tests with red cells of non-human primates.

    PubMed

    Blancher, A; Socha, W W; Reid, M E

    1997-01-01

    Seventy Mabs against human glycophorins (GP) and band 3 were tested with red blood cells (RBCs) of various non-human primates, from anthropoid apes to monkeys. Differences among Mabs reactivity in tests with non-human primate RBCs reflect the complexity of the immune reactions to human GPs and provide insights into aspects of evolution and a tool to epitope map. PMID:9095507

  7. Skin Dictionary

    MedlinePlus

    ... your skin, hair, and nails Skin dictionary Camp Discovery Good Skin Knowledge lesson plans and activities Video library Find a ... your skin, hair, and nails Skin dictionary Camp Discovery Good Skin Knowledge lesson plans and activities Video library Find a ...

  8. Skin graft

    MedlinePlus

    Skin transplant; Skin autografting; FTSG; STSG; Split thickness skin graft; Full thickness skin graft ... site. Most people who are having a skin graft have a split-thickness skin graft. This takes ...

  9. ENVIRONMENTAL REACTIVITY OF SOLID STATE HYDRIDE MATERIALS: MODELING AND TESTING FOR AIR AND WATER EXPOSURE

    SciTech Connect

    Anton, D.; James, C.; Cortes-Concepcion, J.; Tamburello, D.; Brinkman, K.; Gray, J.

    2010-05-18

    To make commercially acceptable condensed phase hydrogen storage systems, it is important to understand quantitatively the risks involved in using these materials. A rigorous set of environmental reactivity tests have been developed based on modified testing procedures codified by the United Nations for the transportation of dangerous goods. Potential hydrogen storage material, 2LiBH4{center_dot}MgH2 and NH3BH3, have been tested using these modified procedures to evaluate the relative risks of these materials coming in contact with the environment in hypothetical accident scenarios. It is apparent that an ignition event will only occur if both a flammable concentration of hydrogen and sufficient thermal energy were available to ignite the hydrogen gas mixture. In order to predict hydride behavior for hypothesized accident scenarios, an idealized finite element model was developed for dispersed hydride from a breached system. Empirical thermodynamic calculations based on precise calorimetric experiments were performed in order to quantify the energy and hydrogen release rates and to quantify the reaction products resulting from water and air exposure. Both thermal and compositional predictions were made with identification of potential ignition event scenarios.

  10. Evaluation of cerebrospinal fluid in Southeast Asian refugees with reactive serologic tests for syphilis.

    PubMed Central

    Buchwald, D; Collier, A C; Lukehart, S A; Kith, P; Goldstein, E; Hooton, T M

    1996-01-01

    To determine the prevalence of cerebrospinal fluid abnormalities in Southeast Asian refugees with reactive serologic tests for syphilis, we evaluated 65 patients, 36 prospectively and 29 retrospectively, in a primary care clinic. Information was collected on history of treponemal infections, neurologic symptoms and signs, and total protein concentration, leukocyte count, and the VDRL test in the cerebrospinal fluid. Neurologic symptoms were reported by all patients for whom data were available. Abnormal neurologic signs were found or noted in medical records in 15 (42%) prospectively evaluated patients and 9 (64%) of 14 retrospectively evaluated patients for whom data were available. No patient had evidence of congenital or non-neurologic sequelae such as cutaneous or cardiovascular manifestations of syphilis. No patient had a positive cerebrospinal fluid VDRL test, 1 had more than 5 x 10(6) leukocytes per liter (5 leukocytes per mm3), and 6 (9%) had elevated total protein levels in the cerebrospinal fluid. Previous therapy for syphilis was not associated with lower serum VDRL reactions, neurologic symptoms and signs, or cerebrospinal fluid findings. In the absence of other indications, routine examination of the cerebrospinal fluid in seropositive Southeast Asian refugees who have nonspecific neurologic symptoms has a low yield, perhaps because of the high prevalence of yaws in this population, and may not be warranted. PMID:8993199

  11. Correlation among skin prick test, total and specific IgE UniCAP tests in atopic patients from Zagreb, Croatia.

    PubMed

    Milavec-Puretić, Visnja; Lipozencić, Jasna; Zizić, Vesna; Milavec, Dinko

    2004-01-01

    The correlation of pollen allergens, Dermatophagoides pteronyssinus and animal dender was assessed during a two-year period. Results of skin prick test, total and specific IgE UniCAP tests were compared in atopic patients (AP) with the following diagnoses: atopic dermatitis, allergic rhinitis, allergic conjunctivitis, allergic bronchitis or asthma, allergic urticaria and angioedema. The study included total and specific IgE (in vitro) tests to allergen mixtures (grass, tree, weed) or to single allergens of Dermatophagoides pteronyssinus (Der p), cat and dog fur, feather, etc. Comparison of skin prick test with total and specific IgE UniCAP immunoassay was done in 173 patients, i.e. 107 female and 66 male atopic patients aged 9-76 years. Allergies were most commonly recorded in the 25-35 age group. Total IgE ranged from 8.63 kU/l to >4000 kU/l, with specific IgE ranging from class 1 to class 5. Skin prick test showed high correlation with specific IgE for grass and weed pollen in patients with repiratory allergy (50.28%). Good correlation among all three tests was quite frequently observed. The results suggest that the study should be continued using these three tests in further cases of atopic dermatitis. PMID:15588558

  12. Use of Specific IgE and Skin Prick Test to Determine Clinical Reaction Severity.

    PubMed

    Ta, Von; Weldon, Brittany; Yu, Grace; Humblet, Olivier; Neale-May, Susan; Nadeau, Kari

    2011-01-01

    AIMS: To determine whether specific IgE and skin prick test correlate better in predicting reaction severity during a double-blinded placebo controlled food challenge (DBPCFC) for egg, milk, and multiple tree nut allergens. STUDY DESIGN: Prospective study. PLACE AND DURATION OF STUDY: Department of Pediatrics, Stanford University School of Medicine, August 2009 and ongoing. METHODOLOGY: We examined the reaction severity of twenty-four subjects to nine possible food allergens: milk, egg, almond, cashew, hazelnut, peanut, sesame, pecan and walnut. Specific IgE and SPT were performed before each DBPCFC. DBPCFC results were classified into mild (1), moderate (2), or severe (3) reactions using a modified Bock's criteria. RESULTS: Twenty four subjects underwent a total of 80 DBPCFC. Eighty percent of all DBPCFCs resulted in a positive reaction. A majority, 71%, were classified as mild. No reactions occurred with a SPT of zero mm while three reactions occurred with a negative specific IgE. All reactions were reversible with medication. CONCLUSION: These data suggest that SPT and specific IgE levels are not associated with reaction severity (p<0.64 and 0.27, respectively). We also found that combining specific IgE and SPT improved specificity but did not help to achieve clinically useful sensitivity. For instance, an SPT > 5mm had a sensitivity of 91% and specificity of 50%. Combining SPT > 5mm and IgE > 7 resulted in a reduced sensitivity of 64%. Unexpectedly, a history of anaphylaxis 70% (n=17) was not predictive of anaphylaxis on challenge 4% (n=2). PMID:22993721

  13. Corrosion resistance and electrochemical potentiokinetic reactivation testing of some iron-base hardfacing alloys

    SciTech Connect

    Cockeram, B.V.

    1999-11-01

    Hardfacing alloys are weld deposited on a base material to provide a wear resistant surface. Commercially available iron-base hardfacing alloys are being evaluated for replacement of cobalt-base alloys to reduce nuclear plant activation levels. Corrosion testing was used to evaluate the corrosion resistance of several iron-base hardfacing alloys in highly oxygenated environments. The corrosion test results indicate that iron-base hardfacing alloys in the as-deposited condition have acceptable corrosion resistance when the chromium to carbon ratio is greater than 4. Tristelle 5183, with a high niobium (stabilizer) content, did not follow this trend due to precipitation of niobium-rich carbides instead of chromium-rich carbides. This result indicates that iron-base hardfacing alloys containing high stabilizer contents may possess good corrosion resistance with Cr:C < 4. NOREM 02, NOREM 01, and NoCo-M2 hardfacing alloys had acceptable corrosion resistance in the as-deposited and 885 C/4 hour heat treated condition, but rusting from sensitization was observed in the 621 C/6 hour heat treated condition. The feasibility of using an Electrochemical Potentiokinetic Reactivation (EPR) test method, such as used for stainless steel, to detect sensitization in iron-base hardfacing alloys was evaluated. A single loop-EPR method was found to provide a more consistent measurement of sensitization than a double loop-EPR method. The high carbon content that is needed for a wear resistant hardfacing alloy produces a high volume fraction of chromium-rich carbides that are attacked during EPR testing. This results in inherently lower sensitivity for detection of a sensitized iron-base hardfacing alloy than stainless steel using conventional EPR test methods.

  14. Hierarchical Testing with Automated Document Generation for Amanzi, ASCEM's Subsurface Flow and Reactive Transport Simulator

    NASA Astrophysics Data System (ADS)

    Moulton, J. D.; Steefel, C. I.; Yabusaki, S.; Castleton, K.; Scheibe, T. D.; Keating, E. H.; Freedman, V. L.

    2013-12-01

    The Advanced Simulation Capabililty for Environmental Management (ASCEM) program is developing an approach and open-source tool suite for standardized risk and performance assessments at legacy nuclear waste sites. These assessments use a graded and iterative approach, beginning with simplified highly abstracted models, and adding geometric and geologic complexity as understanding is gained. To build confidence in this assessment capability, extensive testing of the underlying tools is needed. Since the tools themselves, such as the subsurface flow and reactive-transport simulator, Amanzi, are under active development, testing must be both hierarchical and highly automated. In this presentation we show how we have met these requirements, by leveraging the python-based open-source documentation system called Sphinx with several other open-source tools. Sphinx builds on the reStructured text tool docutils, with important extensions that include high-quality formatting of equations, and integrated plotting through matplotlib. This allows the documentation, as well as the input files for tests, benchmark and tutorial problems, to be maintained with the source code under a version control system. In addition, it enables developers to build documentation in several different formats (e.g., html and pdf) from a single source. We will highlight these features, and discuss important benefits of this approach for Amanzi. In addition, we'll show that some of ASCEM's other tools, such as the sampling provided by the Uncertainty Quantification toolset, are naturally leveraged to enable more comprehensive testing. Finally, we will highlight the integration of this hiearchical testing and documentation framework with our build system and tools (CMake, CTest, and CDash).

  15. Double torsion fracture mechanics testing of shales under chemically reactive conditions

    NASA Astrophysics Data System (ADS)

    Chen, X.; Callahan, O. A.; Holder, J. T.; Olson, J. E.; Eichhubl, P.

    2015-12-01

    Fracture properties of shales is vital for applications such as shale and tight gas development, and seal performance of carbon storage reservoirs. We analyze the fracture behavior from samples of Marcellus, Woodford, and Mancos shales using double-torsion (DT) load relaxation fracture tests. The DT test allows the determination of mode-I fracture toughness (KIC), subcritical crack growth index (SCI), and the stress-intensity factor vs crack velocity (K-V) curves. Samples are tested at ambient air and aqueous conditions with variable ionic concentrations of NaCl and CaCl2, and temperatures up to 70 to determine the effects of chemical/environmental conditions on fracture. Under ambient air condition, KIC determined from DT tests is 1.51±0.32, 0.85±0.25, 1.08±0.17 MPam1/2 for Marcellus, Woodford, and Mancos shales, respectively. Tests under water showed considerable change of KIC compared to ambient condition, with 10.6% increase for Marcellus, 36.5% decrease for Woodford, and 6.7% decrease for Mancos shales. SCI under ambient air condition is between 56 and 80 for the shales tested. The presence of water results in a significant reduction of the SCI from 70% to 85% compared to air condition. Tests under chemically reactive solutions are currently being performed with temperature control. K-V curves under ambient air conditions are linear with stable SCI throughout the load-relaxation period. However, tests conducted under water result in an initial cracking period with SCI values comparable to ambient air tests, which then gradually transition into stable but significantly lower SCI values of 10-20. The non-linear K-V curves reveal that crack propagation in shales is initially limited by the transport of chemical agents due to their low permeability. Only after the initial cracking do interactions at the crack tip lead to cracking controlled by faster stress corrosion reactions. The decrease of SCI in water indicates higher crack propagation velocity due to

  16. Stress reactivity to an electronic version of the Trier Social Stress Test: a pilot study

    PubMed Central

    Hawn, Sage E.; Paul, Lisa; Thomas, Suzanne; Miller, Stephanie; Amstadter, Ananda B.

    2015-01-01

    Social stressors that rely on the inclusion of confederates (i.e., Trier Social Stress Test, TSST) are often used in clinical laboratory research paradigms to elicit a measurable stress response in participants. Although effective, the TSST is labor intensive and may introduce error variance as a function of confederate race, gender, and/or response characteristics. The present study aimed to develop and validate an electronic version of the TSST (e-TSST). The primary aim was to compare the e-TSST to an e-neutral control condition; the exploratory aim was to compare the magnitude of stress response elicited by the e-TSST to that elicited by the traditional TSST. Forty-three healthy adults were randomized to the e-TSST or e-neutral condition. Subjective (participant-rated distress) and objective [cortisol, heart rate (HR), and blood pressure] indices of stress were collected prior to, and multiple times following, the stressor. Using archival data collected from 19 healthy participants exposed to the traditional TSST in a prior study, stress reactivity was compared between the electronic and traditional versions of the TSST. The e-TSST elicited significant increases in all measures of stress reactivity compared to the e-neutral condition, with the exception of HR. Results showed that the magnitude of subjective distress, BP, and HR responses elicited by the e-TSST did not differ significantly from that elicited by the traditional TSST. The traditional TSST elicited significantly higher cortisol than the e-TSST. Although these findings provide initial support for the development of electronic versions of the TSST, further refinement of the e-TSST is warranted prior to broad adoption of this technology. A refined, reliable e-TSST could allow for increased utilization of the TSST by enhancing convenience, reducing labor costs, and limiting potential error variance introduced by human confederates. PMID:26074862

  17. Sympathetic neural reactivity to mental stress in humans: test-retest reproducibility.

    PubMed

    Fonkoue, Ida T; Carter, Jason R

    2015-12-01

    Mental stress consistently increases arterial blood pressure, but this reliable pressor response is often associated with highly variable muscle sympathetic nerve activity (MSNA) responsiveness between individuals. Although MSNA has been shown to be reproducible within individuals at rest and during the cold pressor test (CPT), intraindividual reproducibility of MSNA responsiveness to mental stress has not been adequately explored. The purpose of this study was to examine MSNA reactivity to mental stress across three experimental sessions. Sixteen men and women (age 21 ± 1 yr) performed two experimental sessions within a single laboratory visit and a third experimental session 1 mo later. Each experimental session consisted of a mental stress trial via mental arithmetic and a CPT trial. Blood pressure, heart rate (HR), and MSNA were measured, and the consistencies of these variables were determined using intraclass correlation (Cronbach's α coefficient). MSNA, mean arterial pressure (MAP), and HR were highly reproducible across the baselines preceding mental stress (Cronbach's α ≥ 0.816, P ≤ 0.001) and CPT (Cronbach's α ≥ 0.782, P ≤ 0.001). Across the three mental stress trials, changes in MSNA (Cronbach's α = 0.875; P = 0.001), MAP (Cronbach's α = 0.749; P < 0.001), and HR (Cronbach's α = 0.919; P < 0.001) were reproducible. During CPT, changes in MSNA (Cronbach's α = 0.805; P = 0.008), MAP (Cronbach's α = 0.878; P < 0.001), and HR (Cronbach's α = 0.927; P < 0.001) remained consistent across the three sessions. In conclusion, our findings demonstrate that MSNA reactivity to mental stress is consistent within a single laboratory visit and across laboratory sessions conducted on separate days. PMID:26400186

  18. Testing hypotheses of soil organic matter dynamics in a mechanistic reactive transport model

    NASA Astrophysics Data System (ADS)

    Riley, W. J.; Maggi, F.; Guerry, N.; Torn, M. S.; Kleber, M.

    2012-12-01

    The range of processes hypothesized to be important for long-term soil organic matter dynamics far exceeds the capabilities of current land models integrated in regional- to global-scale climate models. Yet SOM stability and CO2 fluxes from soils to the atmosphere are critical for future projections of climate. Recent syntheses of processes that may influence the trajectory of future soil C storage emphasize mineral interactions, enzyme dynamics, microbial population dynamics, transport, and interactions with plants and nutrient cycles. We contend that evaluating the relative importance of these processes requires a numerical modelling structure that allows for consistent comparison with observations, uncertainty characterization, and as mechanistic as possible a representation of the processes. We will describe a detailed spatially-resolved 3-dimensional reactive transport solver (TOUGHREACT) that represents abiotic and biotic SOM transformations and multi-phase flows. The modelling framework allows for explicit representation of (1) SOM interactions with minerals and their temperature, pH, and redox dependencies; (2) multiple microbial groups with different survival strategies and environmental sensitivities; (3) aqueous, gaseous, and sorbed phases; and (4) disaggregation of litter inputs, depolymerisation productions, and microbial bodies into an arbitrary number of SOM functional groups. The model accurately represented vertically-resolved bulk SOM in grassland and forest ecosystems using a baseline set of parameters. After testing, we used the model to investigate the relative impact of various mechanisms affecting SOM storage. Model predictions highlight the importance of sorption, aqueous transport, and microbial dynamics for the slow turnover of SOM that is observed below the rooting zone. We will also describe (1) model structural and parametric uncertainty; (2) methods to extract low-order model representations from the detailed reactive transport

  19. Feed efficiency effects on barrow and gilt behavioral reactivity to novel stimuli tests.

    PubMed

    Colpoys, J D; Abell, C E; Gabler, N K; Keating, A F; Millman, S T; Siegford, J M; Young, J M; Johnson, A K

    2015-03-01

    Increasing feed efficiency is an important goal for improving sustainable pork production and profitability for producers. To study feed efficiency, genetic selection based on residual feed intake (RFI) was used to create 2 divergent lines. Low-RFI pigs consume less feed for equal weight gain compared to their less efficient, high-RFI counterparts. Therefore, our objective was to assess how a pig's behavioral reactivity toward fear-eliciting stimuli related to RFI selection and improvement of feed efficiency. In this study, behavioral reactivity of pigs divergently selected for RFI was evaluated using human approach (HAT) and novel object (NOT) tests. Forty low-RFI and 40 high-RFI barrows and gilts ( = 20 for each genetic line; 101 ± 9 d old) from ninth-generation Yorkshire RFI selection lines were randomly selected and evaluated once using HAT and once using NOT over a 2-wk period utilizing a crossover experimental design. Each pig was individually tested within a 4.9 × 2.4 m test arena for 10 min; behavior was evaluated using live and video observations. The test arena floor was divided into 4 zones; zone 1 being oral, nasal, and/or facial contact with the human (HAT) or orange traffic cone (NOT) and zone 4 being furthest from the human or cone and included the point where the pig entered the arena. During both HAT and NOT, low-RFI pigs entered zone 1 less frequently compared to high-RFI pigs ( ≤ 0.03). During NOT, low-RFI pigs changed head orientation more frequently ( = 0.001) but attempted to escape less frequently (low-RFI = 0.97 ± 0.21 vs. high-RFI = 2.08 ± 0.38; = 0.0002) and spent 2% less time attempting to escape compared to high-RFI pigs ( = 0.04). Different barrow and gilt responses were observed during HAT and NOT. During HAT, barrows spent 2% more time within zone 1 ( = 0.03), crossed fewer zone lines ( < 0.0001), changed head orientation less frequently ( = 0.002), and froze less frequently compared to gilts ( = 0.02). However, during NOT

  20. FUNDAMENTAL ENVIRONMENTAL REACTIVITY TESTING AND ANALYSIS OF THE HYDROGEN STORAGE MATERIAL 2LIBH4 MGH2

    SciTech Connect

    James, C.; Anton, D.; Cortes-Concepcion, J.; Brinkman, K.; Gray, J.

    2012-01-10

    While the storage of hydrogen for portable and stationary applications is regarded as critical in bringing PEM fuel cells to commercial acceptance, little is known of the environmental exposure risks posed in utilizing condensed phase chemical storage options as in complex hydrides. It is thus important to understand the effect of environmental exposure of metal hydrides in the case of accident scenarios. Simulated tests were performed following the United Nations standards to test for flammability and water reactivity in air for a destabilized lithium borohydride and magnesium hydride system in a 2 to 1 molar ratio respectively. It was determined that the mixture acted similarly to the parent, lithium borohydride, but at slower rate of reaction seen in magnesium hydride. To quantify environmental exposure kinetics, isothermal calorimetry was utilized to measure the enthalpy of reaction as a function of exposure time to dry and humid air, and liquid water. The reaction with liquid water was found to increase the heat flow significantly during exposure compared to exposure in dry or humid air environments. Calorimetric results showed the maximum normalized heat flow the fully charged material was 6 mW/mg under liquid phase hydrolysis; and 14 mW/mg for the fully discharged material also occurring under liquid phase hydrolysis conditions.

  1. Dissolution-precipitation processes in tank experiments for testing numerical models for reactive transport calculations: Experiments and modelling

    NASA Astrophysics Data System (ADS)

    Poonoosamy, Jenna; Kosakowski, Georg; Van Loon, Luc R.; Mäder, Urs

    2015-06-01

    In the context of testing reactive transport codes and their underlying conceptual models, a simple 2D reactive transport experiment was developed. The aim was to use simple chemistry and design a reproducible and fast to conduct experiment, which is flexible enough to include several process couplings: advective-diffusive transport of solutes, effect of liquid phase density on advective transport, and kinetically controlled dissolution/precipitation reactions causing porosity changes. A small tank was filled with a reactive layer of strontium sulfate (SrSO4) of two different grain sizes, sandwiched between two layers of essentially non-reacting quartz sand (SiO2). A highly concentrated solution of barium chloride was injected to create an asymmetric flow field. Once the barium chloride reached the reactive layer, it forced the transformation of strontium sulfate into barium sulfate (BaSO4). Due to the higher molar volume of barium sulfate, its precipitation caused a decrease of porosity and lowered the permeability. Changes in the flow field were observed with help of dye tracer tests. The experiments were modelled using the reactive transport code OpenGeosys-GEM. Tests with non-reactive tracers performed prior to barium chloride injection, as well as the density-driven flow (due to the high concentration of barium chloride solution), could be well reproduced by the numerical model. To reproduce the mineral bulk transformation with time, two populations of strontium sulfate grains with different kinetic rates of dissolution were applied. However, a default porosity permeability relationship was unable to account for measured pressure changes. Post mortem analysis of the strontium sulfate reactive medium provided useful information on the chemical and structural changes occurring at the pore scale at the interface that were considered in our model to reproduce the pressure evolution with time.

  2. Dissolution-precipitation processes in tank experiments for testing numerical models for reactive transport calculations: Experiments and modelling.

    PubMed

    Poonoosamy, Jenna; Kosakowski, Georg; Van Loon, Luc R; Mäder, Urs

    2015-01-01

    In the context of testing reactive transport codes and their underlying conceptual models, a simple 2D reactive transport experiment was developed. The aim was to use simple chemistry and design a reproducible and fast to conduct experiment, which is flexible enough to include several process couplings: advective-diffusive transport of solutes, effect of liquid phase density on advective transport, and kinetically controlled dissolution/precipitation reactions causing porosity changes. A small tank was filled with a reactive layer of strontium sulfate (SrSO4) of two different grain sizes, sandwiched between two layers of essentially non-reacting quartz sand (SiO2). A highly concentrated solution of barium chloride was injected to create an asymmetric flow field. Once the barium chloride reached the reactive layer, it forced the transformation of strontium sulfate into barium sulfate (BaSO4). Due to the higher molar volume of barium sulfate, its precipitation caused a decrease of porosity and lowered the permeability. Changes in the flow field were observed with help of dye tracer tests. The experiments were modelled using the reactive transport code OpenGeosys-GEM. Tests with non-reactive tracers performed prior to barium chloride injection, as well as the density-driven flow (due to the high concentration of barium chloride solution), could be well reproduced by the numerical model. To reproduce the mineral bulk transformation with time, two populations of strontium sulfate grains with different kinetic rates of dissolution were applied. However, a default porosity permeability relationship was unable to account for measured pressure changes. Post mortem analysis of the strontium sulfate reactive medium provided useful information on the chemical and structural changes occurring at the pore scale at the interface that were considered in our model to reproduce the pressure evolution with time. PMID:25805363

  3. Application of Concanavalin A during immune responsiveness skin-swelling tests facilitates measurement interpretation in mammalian ecology.

    PubMed

    Bílková, Barbora; Albrecht, Tomáš; Chudíčková, Milada; Holáň, Vladimír; Piálek, Jaroslav; Vinkler, Michal

    2016-07-01

    The skin-swelling test is a simple and widespread method used in field ecological research to estimate cellular immune responsiveness in animals. This immunoecological test is based on measuring the magnitude of tissue swelling response at specific times following subcutaneous application of an experimental pro-inflammatory stimulant. In the vast majority of studies across vertebrate taxa, phytohemagglutinin (PHA) is used as a universal stimulant. Given the complexity of immune response activation pathways of PHA, however, interpretation of test results can be ambiguous. Goal of this study was to improve methodology of the skin-swelling test to decrease this ambiguity. Here, we present an alternative protocol aimed at facilitating interpretation of skin-swelling data for mammals. Based on previous evidence suggesting that mammalian T cells are readily activated by Concanavalin A (ConA) in vitro, we compared cellular immune responses in vivo to PHA and ConA as an alternative pro-inflammatory stimulant in mice. We measured magnitude of tissue swelling and compared it with intensity of blood cell infiltration into tissue over a 72-hour interval. Our results corroborate that PHA and ConA show important differences in both dynamics and response amplitude in rodents. ConA induces stronger swelling with a distinct leukocyte activity pattern and higher pro-inflammatory cytokine (interleukin 6 [IL-6] and interferon gamma[IFN-γ]) expression than PHA during peak response (24-h post-treatment). Furthermore, unlike PHA, magnitude of swelling was positively associated with cellular activity (number of neutrophils infiltrating tissue) following ConA injection. We conclude that ConA is the more suitable stimulant for skin-swelling tests in mammals. This is because of the molecular binding specificity in the two lectins, that is, ConA specifically activates T cells while PHA also triggers erythroagglutination. We propose that ConA be used in all future ecological testing in

  4. Allergic contact dermatitis to plants: an analysis of 68 patients tested at the Skin and Cancer Foundation.

    PubMed

    Cook, D K; Freeman, S

    1997-08-01

    Allergic contact dermatitis to plant allergens is a common problem in Australia. We present the cumulative experience of the Contact Dermatitis Clinic of the Skin and Cancer Foundation (Darlinghurst, NSW, Australia) a tertiary referral clinic. Results from a series of 68 patients with positive patch tests to 88 plant allergens are reported. We found that Grevillea species, Compositae, Rhus, Alstroemeria and various timber sawdusts were the most common plant allergens. PMID:9293658

  5. Testing thick-skinned vs thin-skinned faulting in the Yakima fold and thrust belt, Washington: kinematic modeling based on new geologic mapping

    NASA Astrophysics Data System (ADS)

    Miller, B. A.; Crider, J. G.

    2012-12-01

    The greater Cascadia region contains abundant evidence for geologically recent deformation due to movement on upper crustal faults, which pose a seismic hazard independent of great earthquakes on the subduction zone interface. Located in the backarc of Cascadia, the structures of the Yakima fold and thrust belt in central Washington record Miocene to present deformation of the Columbia River Basalt Group (CRBG); however, the geometry of the faults responsible is not well constrained by prior work. Depth of faulting in particular plays a first-order role in determining the maximum credible earthquake for seismic hazard planning. Previous studies assuming thin-skinned tectonics for the Yakima fold and thrust belt imply significantly lower estimates for the maximum credible earthquake. Evidence from geophysical anomalies requires km scale relief on the pre-Tertiary basement underneath the CRBG and Tertiary continental sedimentary rocks. If pre-Tertiary basement relief is due to slip on basement involved reverse faults kinematically coherent with the shallower folds and faults, then the estimates for the maximum credible earthquakes may have to be revisited. These end-member hypotheses of thin-skinned versus basement-involved deformation can be tested with kinematic models of different fault geometries. Kinematic modeling software (Midland Valley's Move) provides a robust method for the construction of balanced (retro-deformable) cross sections constrained by surficial and subsurface geologic data. We present new geologic mapping in the area of the intersection between Umtanum Ridge and the Yakima River Canyon north of Selah, Washington. Umtanum Ridge lies along the Olympic-Wallowa lineament (OWL), which may be the physiographic manifestation of active structures that extend through the Cascade Range and into western Washington. Geologic mapping was facilitated by high resolution DEMs from airborne laser swath mapping (lidar), along with chemo

  6. Performance of skin tests with allergens from B. melitensis B115 and rough B. abortus mutants for diagnosing swine brucellosis.

    PubMed

    Dieste-Pérez, L; Blasco, J M; De Miguel, M J; Marín, C M; Barberán, M; Conde-Álvarez, R; Moriyón, I; Muñoz, P M

    2014-01-10

    Swine brucellosis by Brucella suis biovar 2 is an emerging disease whose control is based on serological testing and culling. However, current serological tests detect antibodies to the O-polysaccharide (O/PS) moiety of Brucella smooth lipopolysaccharide (S-LPS), and thus lack specificity when infections by Yersinia enterocolitica O:9 and other gram-negative bacteria carrying cross-reacting O/PS occur. The skin test with the protein-rich brucellin extract obtained from rough B. melitensis B115 is assumed to be specific for discriminating these false positive serological reactions (FPSR). However, B115 strain, although unable to synthesize S-LPS, accumulates O/PS internally, which could cause diagnostic problems. Since the brucellin skin test has been seldom used in pigs and FPSR are common in these animals, we assessed its performance using cytosoluble protein extracts obtained from B. abortus rough mutants in manBcore or per genes (critical for O/PS biosynthesis) and B. melitensis B115. The diagnostic sensitivity and specificity were determined in B. suis biovar 2 culture positive and brucellosis free sows, and apparent prevalence in sows of unknown individual bacteriological and serological status belonging to B. suis biovar 2 naturally infected herds. Moreover, the specificity in discriminating brucellosis from FPSR was assessed in brucellosis free boars showing FPSR. The skin test with B. abortus ΔmanBcore and B. melitensis B115 allergens performed similarly, and the former one resulted in 100% specificity when testing animals showing FPSR in indirect ELISA, Rose Bengal and complement fixation serological tests. We conclude that O/PS-free genetically defined mutants represent an appropriate alternative to obtain Brucella protein extracts for diagnosing swine brucellosis. PMID:24331743

  7. Column Testing and 1D Reactive Transport Modeling to Evaluate Uranium Plume Persistence Processes

    NASA Astrophysics Data System (ADS)

    Johnson, R. H.; Morrison, S.; Morris, S.; Tigar, A.; Dam, W. L.; Dayvault, J.

    2015-12-01

    At many U.S. Department of Energy Office of Legacy Management sites, 100 year natural flushing was selected as a remedial option for groundwater uranium plumes. However, current data indicate that natural flushing is not occurring as quickly as expected and solid-phase and aqueous uranium concentrations are persistent. At the Grand Junction, Colorado office site, column testing was completed on core collected below an area where uranium mill tailings have been removed. The total uranium concentration in this core was 13.2 mg/kg and the column was flushed with laboratory-created water with no uranium and chemistry similar to the nearby Gunnison River. The core was flushed for a total of 91 pore volumes producing a maximum effluent uranium concentration of 6,110 μg/L at 2.1 pore volumes and a minimum uranium concentration of 36.2 μg/L at the final pore volume. These results indicate complex geochemical reactions at small pore volumes and a long tailing affect at greater pore volumes. Stop flow data indicate the occurrence of non-equilibrium processes that create uranium concentration rebound. These data confirm the potential for plume persistence, which is occurring at the field scale. 1D reactive transport modeling was completed using PHREEQC (geochemical model) and calibrated to the column test data manually and using PEST (inverse modeling calibration routine). Processes of sorption, dual porosity with diffusion, mineral dissolution, dispersion, and cation exchange were evaluated separately and in combination. The calibration results indicate that sorption and dual porosity are major processes in explaining the column test data. These processes are also supported by fission track photographs that show solid-phase uranium residing in less mobile pore spaces. These procedures provide valuable information on plume persistence and secondary source processes that may be used to better inform and evaluate remedial strategies, including natural flushing.

  8. Non-invasive methods to establish the diagnosis of terra firma-forme dermatosis: The SMART (Skin Modified by Alcohol Rubbing Test) evaluation and dermoscopy.

    PubMed

    Greywal, Tanya; Cohen, Philip R

    2016-01-01

    Terra firma-forme dermatosis may mimic a variety of hyper pigmented dermatoses.  The diagnosis can be characterized using dermoscopy and confirmed with the SMART (Skin Modified by Alcohol Rubbing Test) evaluation.  When terra firma-forme dermatosis (Duncan's dirty dermatosis) is clinically suspected, clearance of the dermatosis follows rubbing the affected skin with 70% isopropyl alcohol. PMID:27617614

  9. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ....5270 Section 866.5270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... the C-reactive protein in serum and other body fluids. Measurement of C-reactive protein aids in evaluation of the amount of injury to body tissues. (b) Classification. Class II (performance standards)....

  10. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ....5270 Section 866.5270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... the C-reactive protein in serum and other body fluids. Measurement of C-reactive protein aids in evaluation of the amount of injury to body tissues. (b) Classification. Class II (performance standards)....

  11. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ....5270 Section 866.5270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... the C-reactive protein in serum and other body fluids. Measurement of C-reactive protein aids in evaluation of the amount of injury to body tissues. (b) Classification. Class II (performance standards)....

  12. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ....5270 Section 866.5270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... the C-reactive protein in serum and other body fluids. Measurement of C-reactive protein aids in evaluation of the amount of injury to body tissues. (b) Classification. Class II (performance standards)....

  13. Proposal of abolition of the skin sensitivity test before equine rabies immune globulin application.

    PubMed

    Cupo, P; de Azevedo-Marques, M M; Sarti, W; Hering, S E

    2001-01-01

    An epizootic outbreak of rabies occurred in 1995 in Ribeirão Preto, SP, with 58 cases of animal rabies (54 dogs, 3 cats and 1 bat) confirmed by the Pasteur Institute of São Paulo, and one human death. The need to provide care to a large number of people for the application of equine rabies immune globulin (ERIG) prevented the execution of the skin sensitivity test (SST) and often also the execution of desensitization, procedures routinely used up to that time at the Emergency Unit of the University Hospital of the Faculty of Medicine of Ribeirão Preto, University of São Paulo (EU-UHFMRP-USP), a reference hospital for the application of heterologous sera. In view of our positive experience of several years with the abolition of SST and of the use of premedication before the application of antivenom sera, we used a similar schedule for ERIG application. Of the 1489 victims of animal bites, 1054 (71%) received ERIG; no patient was submitted to SST and all received intravenously anti-histamines (anti-H1 + anti-H2) and corticosteroids before the procedure. The patients were kept under observation for 60 to 180 minutes and no adverse reaction was observed. On the basis of these results, since December 1995 ERIG application has been decentralized in Ribeirão Preto and has become the responsibility of the Emergency Unit of the University Hospital and the Central Basic Health Unit, where the same routine is used. Since then, 4216 patients have received ERIG (1818 at the Basic Health Unit and 2398 at the EU-UHFMRP), with no problems. The ideal would be the routine use of human rabies immune globulin (HRIG) in public health programs, but this is problematic, because of their high cost. However, while this does not occur, the use of SST is no longer justified at the time of application of ERIG, in view of the clinical evidence of low predictive value and low sensitivity of SST involving the application of heterologous sera. It is very important to point out that a

  14. DOSE-RESPONSE FOR UV-INDUCED IMMUNE SUPPRESSION IN PEOPLE OF COLOR: DIFFERENCES BASED ON ERYTHEMAL REACTIVITY RATHER THAN SKIN PIGMENTATION

    EPA Science Inventory

    Ultraviolet radiation (UVR) is known to suppress immune responses in human subjects. The purpose of this study was to develop dose responses across a broad range of skin pigmentation in order to facilitate risk assessment. UVR was administered using FS 20 bulbs. Skin pigmentation...

  15. Sagging Skin

    MedlinePlus

    ... Non-ablative Laser Rejuvenation Non-invasive Body Contouring Treatments Skin Cancer Skin Cancer Information Free Skin Cancer Screenings Skin ... Non-ablative Laser Rejuvenation Non-invasive Body Contouring Treatments Skin Cancer Skin Cancer Information Free Skin Cancer Screenings Skin ...

  16. Skin Diseases: Skin Health and Skin Diseases

    MedlinePlus

    ... the sun. Photo: PhotoDisc Care for conditions from acne to wrinkles Did you know that your skin ... other skin conditions. Many skin problems, such as acne, also affect your appearance. Your skin can also ...

  17. Test Problems for Reactive Flow HE Model in the ALE3D Code and Limited Sensitivity Study

    SciTech Connect

    Gerassimenko, M.

    2000-03-01

    We document quick running test problems for a reactive flow model of HE initiation incorporated into ALE3D. A quarter percent change in projectile velocity changes the outcome from detonation to HE burn that dies down. We study the sensitivity of calculated HE behavior to several parameters of practical interest where modeling HE initiation with ALE3D.

  18. A test on reactive force fields for the study of silica dimerization reactions

    SciTech Connect

    Moqadam, Mahmoud; Riccardi, Enrico; Trinh, Thuat T.; Åstrand, Per-Olof; Erp, Titus S. van

    2015-11-14

    We studied silica dimerization reactions in the gas and aqueous phase by density functional theory (DFT) and reactive force fields based on two parameterizations of ReaxFF. For each method (both ReaxFF force fields and DFT), we performed constrained geometry optimizations, which were subsequently evaluated in single point energy calculations using the other two methods. Standard fitting procedures typically compare the force field energies and geometries with those from quantum mechanical data after a geometry optimization. The initial configurations for the force field optimization are usually the minimum energy structures of the ab initio database. Hence, the ab initio method dictates which structures are being examined and force field parameters are being adjusted in order to minimize the differences with the ab initio data. As a result, this approach will not exclude the possibility that the force field predicts stable geometries or low transition states which are realistically very high in energy and, therefore, never considered by the ab initio method. Our analysis reveals the existence of such unphysical geometries even at unreactive conditions where the distance between the reactants is large. To test the effect of these discrepancies, we launched molecular dynamics simulations using DFT and ReaxFF and observed spurious reactions for both ReaxFF force fields. Our results suggest that the standard procedures for parameter fitting need to be improved by a mutual comparative method.

  19. Characterizing switching and congruency effects in the Implicit Association Test as reactive and proactive cognitive control.

    PubMed

    Hilgard, Joseph; Bartholow, Bruce D; Dickter, Cheryl L; Blanton, Hart

    2015-03-01

    Recent research has identified an important role for task switching, a cognitive control process often associated with executive functioning, in the Implicit Association Test (IAT). However, switching does not fully account for IAT effects, particularly when performance is scored using more recent d-score formulations. The current study sought to characterize multiple control processes involved in IAT performance through the use of event-related brain potentials (ERPs). Participants performed a race-evaluative IAT while ERPs were recorded. Behaviorally, participants experienced superadditive reaction time costs of incongruency and task switching, consistent with previous studies. The ERP showed a marked medial frontal negativity (MFN) 250-450 ms post-stimulus at midline fronto-central locations that were more negative for incongruent than congruent trials but more positive for switch than for no-switch trials, suggesting separable control processes are engaged by these two factors. Greater behavioral IAT bias was associated with both greater switch-related and congruency-related ERP activity. Findings are discussed in terms of the Dual Mechanisms of Control model of reactive and proactive cognitive control. PMID:24812074

  20. Mineralogy, geochemistry and expansion testing of an alkali-reactive basalt from western Anatolia, Turkey

    SciTech Connect

    Copuroglu, Oguzhan; Andic-Cakir, Ozge; Broekmans, Maarten A.T.M.; Kuehnel, Radko

    2009-07-15

    In this paper, the alkali-silica reaction performance of a basalt rock from western Anatolia, Turkey is reported. It is observed that the rock causes severe gel formation in the concrete microbar test. It appears that the main source of expansion is the reactive glassy phase of the basalt matrix having approximately 70% of SiO{sub 2}. The study presents the microstructural characteristics of unreacted and reacted basalt aggregate by optical and electron microscopy and discusses the possible reaction mechanism. Microstructural analysis revealed that the dissolution of silica is overwhelming in the matrix of the basalt and it eventually generates four consequences: (1) Formation of alkali-silica reaction gel at the aggregate perimeter, (2) increased porosity and permeability of the basalt matrix, (3) reduction of mechanical properties of the aggregate and (4) additional gel formation within the aggregate. It is concluded that the basalt rock is highly prone to alkali-silica reaction. As an aggregate, this rock is not suitable for concrete production.

  1. Skin Irritation to Glass Wool or Continuous Glass Filaments as Observed by a Patch Test among Human Japanese Volunteers

    PubMed Central

    TSUNODA, Masashi; KIDO, Takamasa; MOGI, Sachiyo; SUGIURA, Yumiko; MIYAJIMA, Eriko; KUDO, Yuichiro; KUMAZAWA, Tatenao; AIZAWA, Yoshiharu

    2014-01-01

    Glass wool and continuous glass filaments have been used in industry. We examined the irritability of those among Japanese. A patch test was performed on 43 volunteers for the followings: glass wool for non-residential use with and without a urea-modified phenolic resin binder, that for residential use with and without the binder, and continuous glass filaments with diameters of 4, 7, 9, and 13 µm. Materials were applied to an upper arm of each volunteer for 24 h. The skin was observed at 1 and 24 h after the removal. At 1 h after removal, slight erythema was observed on the skin of a woman after the exposure to glass wool for residential use without the binder. Erythema was observed on the skin of another woman at 1 h after a 24-h exposure to glass wool for non-residential use without the binder. There were no reactions at 24 h after the removal. The low reactions in the patch test suggested that the irritability caused by glass wool, irrespective of a resin component, could be induced mechanically, and that the irritability caused by continuous glass filaments with resin could be slight and either mechanical or chemical. PMID:25070402

  2. New strategies for development of a safe and effective skin decontamination system. Final report, 24 May 1986-23 April 1989

    SciTech Connect

    Langenmayr, E.J.

    1992-02-01

    Under previous contract to USAMRDC, Rohm and Haas Company has demonstrated the concept of using small particle size, insoluble reactive and sorptive resins as the basis for a safe and effective skin decontamination kit (SDK). The objective of the current contract is to identify new resins for skin decontamination which show improved reactivity, sorptivity, and retentivity for CW agents over those resins evaluated in previous contracts yet which remain safe for use on human skin. Nineteen sorbent resins were evaluated in Phase I. Porous resins based on polystyrene, polyacrylate, phenol -formaldehyde, and carbonaceous matrices were tested. The sorbent resins were evaluated using the competition test, vapor phase desorption test, contact desorption test, and Enslinn test. skin decontamination, CW agents, reactivity, chloroethylisobutyl sulfide, diisopropylfluorophosphate, sorbent resins, reactive resins, carbonaceous, macronet, hydroxide.

  3. Multi-laboratory validation of SkinEthic HCE test method for testing serious eye damage/eye irritation using liquid chemicals.

    PubMed

    Alépée, N; Leblanc, V; Adriaens, E; Grandidier, M H; Lelièvre, D; Meloni, M; Nardelli, L; Roper, C S; Santirocco, E; Toner, F; Van Rompay, A; Vinall, J; Cotovio, J

    2016-03-01

    A prospective multicentric study of the reconstructed human corneal epithelial tissue-based in vitro test method (SkinEthic™ HCE) was conducted to evaluate its usefulness to identify chemicals as either not classified for serious eye damage/eye irritation (No Cat.) or as classified (Cat. 1/Cat. 2) within UN GHS. The aim of this study was to demonstrate the transferability and reproducibility of the SkinEthic™ HCE EITL protocol for liquids and define its predictive capacity. Briefly, 60 chemicals were three times tested (double blinded) in 3 laboratories and 45 additional chemicals were tested three times in one laboratory. Good within laboratory reproducibility was achieved of at least 88.3% (53/60) and 92.4% (97/105) for the extended data set. Furthermore, the overall concordance between the laboratories was 93.3% (56/60). The accuracy of the SkinEthic™ HCE EITL for the extended dataset, based on bootstrap resampling, was 84.4% (95% CI: 81.9% to 87.6%) with a sensitivity of 99.0% (95% CI: 96.4% to 100%) and specificity of 68.5% (95% CI: 64.0% to 74.0%), thereby meeting all acceptance criteria for predictive capacity. This efficient transferable and reproducible assay is a promising tool to be integrated within a battery of assays to perform an eye irritation risk assessment. PMID:26612353

  4. Skin Injuries Reduce Survival and Modulate Corticosterone, C-Reactive Protein, Complement Component 3, IgM, and Prostaglandin E2 after Whole-Body Reactor-Produced Mixed Field (n + γ-Photons) Irradiation

    PubMed Central

    Kiang, Juliann G.; Ledney, G. David

    2013-01-01

    Skin injuries such as wounds or burns following whole-body γ-irradiation (radiation combined injury (RCI)) increase mortality more than whole-body γ-irradiation alone. Wound-induced decreases in survival after irradiation are triggered by sustained activation of inducible nitric oxide synthase pathways, persistent alteration of cytokine homeostasis, and increased susceptibility to systemic bacterial infection. Among these factors, radiation-induced increases in interleukin-6 (IL-6) concentrations in serum were amplified by skin wound trauma. Herein, the IL-6-induced stress proteins including C-reactive protein (CRP), complement 3 (C3), immunoglobulin M (IgM), and prostaglandin E2 (PGE2) were evaluated after skin injuries given following a mixed radiation environment that might be found after a nuclear incident. In this report, mice received 3 Gy of reactor-produced mixed field (n + γ-photons) radiations at 0.38 Gy/min followed by nonlethal skin wounding or burning. Both wounds and burns reduced survival and increased CRP, C3, and PGE2 in serum after radiation. Decreased IgM production along with an early rise in corticosterone followed by a subsequent decrease was noted for each RCI situation. These results suggest that RCI-induced alterations of corticosterone, CRP, C3, IgM, and PGE2 cause homeostatic imbalance and may contribute to reduced survival. Agents inhibiting these responses may prove to be therapeutic for RCI and improve related survival. PMID:24175013

  5. Field Method for Testing Repellency of an Icaridin-Containing Skin Lotion against Vespid Wasps.

    PubMed

    Boevé, Jean-Luc; Eertmans, Frank; Adriaens, Els; Rossel, Bart

    2016-01-01

    Vespid wasps are ecologically beneficial predators of insects but their stings also pose a human health risk. Current control methods based on killing vespids are suboptimal. Here, the repellent effect against Vespula vulgaris of a 20% icaridin skin lotion was evaluated under field conditions. An experimental setup was designed in which six artificial skin pieces (10 × 10 cm) were video-recorded for 1 h, to count each min the numbers of flying and feeding vespids. Prior to monitoring, five pieces were successively smeared with 2 mg of cream per cm², in 30 min intervals, from t = -120 min to 0. The sixth sheet remained untreated to serve as a control. One milliliter of an attractant, fruit jam, was deposited on each of the six surfaces at t = 0. The control surface was free of any flying or feeding vespid during an average period of 25 min, whereas the other five surfaces (treated at t = -120, -90, -60, -30, and 0 min) remained vespid-free for 39, 40, 45, 49, and 51 min, respectively. The skin lotion remained significantly active for at least 2 h. The experimental methodology is adjustable and allows the study of repellents against vespids in semi-natural conditions. PMID:27271672

  6. Field Method for Testing Repellency of an Icaridin-Containing Skin Lotion against Vespid Wasps

    PubMed Central

    Boevé, Jean-Luc; Eertmans, Frank; Adriaens, Els; Rossel, Bart

    2016-01-01

    Vespid wasps are ecologically beneficial predators of insects but their stings also pose a human health risk. Current control methods based on killing vespids are suboptimal. Here, the repellent effect against Vespula vulgaris of a 20% icaridin skin lotion was evaluated under field conditions. An experimental setup was designed in which six artificial skin pieces (10 × 10 cm) were video-recorded for 1 h, to count each min the numbers of flying and feeding vespids. Prior to monitoring, five pieces were successively smeared with 2 mg of cream per cm2, in 30 min intervals, from t = −120 min to 0. The sixth sheet remained untreated to serve as a control. One milliliter of an attractant, fruit jam, was deposited on each of the six surfaces at t = 0. The control surface was free of any flying or feeding vespid during an average period of 25 min, whereas the other five surfaces (treated at t = −120, −90, −60, −30, and 0 min) remained vespid-free for 39, 40, 45, 49, and 51 min, respectively. The skin lotion remained significantly active for at least 2 h. The experimental methodology is adjustable and allows the study of repellents against vespids in semi-natural conditions. PMID:27271672

  7. Detection and measurement of a cellular immune-reactivity towards polyester and polytetrafluoroethylene grafts. Leukocyte adherence inhibition test.

    PubMed

    Cavallini, G; Lanfredi, M; Lodi, M; Govoni, M; Pampolini, M

    1987-03-01

    Several studies were performed on polyester (Dacron) and polytetrafluoroethylene (PTFE) vascular substitute thrombogenicity. However, to date, the host-graft interactions have yet to be studied from an immunological point of view. For this reason, 4 classes of 10 patients each (Class 1: Dacron-+PTFE-grafted patients, Class 2: Dacron-, Class 3: PTFE-, and Class 4: controls) were submitted to a cellular immune-reactivity test: leukocyte adherence inhibition (LAI), in which leukocytes fail to adhere to glass on contact with a sensitizing antigen. The following blood cell populations were used: total leukocytes (PBL), mononuclear cells (MNC), T and B lymphocytes. This research demonstrated that a T cellular immune-reactivity towards Dacron and PTFE respectively occurs in Dacron- and PTFE-grafted patients, and that this reactivity is greater in the case of Dacron. More studies are required to determine the immuno-competent system role in fabric prosthesis patency. PMID:2955626

  8. Electrodermal reactivity during the Trier Social Stress Test for children: interaction between the serotonin transporter polymorphism and children's attachment representation.

    PubMed

    Gilissen, Renske; Bakermans-Kranenburg, Marian J; van Ijzendoorn, Marinus H; Linting, Mariëlle

    2008-09-01

    This study explores the relation between variations in the serotonin transporter gene (5-HTTLPR; long vs. short allele), the child's attachment representation (assessed with the Attachment Story Completion Task, reflecting the security of the parent-child relationship), and electrodermal reactivity during a public speaking task, the Trier Social Stress Test for Children (TSST-C) in a sample of 92 7-year-old. Electrodermal reactivity during the TSST-C was not directly associated with variations in 5-HTT. However, there was a significant gene-environment interaction effect of 5-HTT and attachment security on electrodermal reactivity. Results are interpreted in terms of cumulative protection: Children with a secure attachment representation as well as long 5-HTT alleles appeared to be less stressed during the TSST-C. PMID:18683185

  9. Sensitivity of C-Tb: a novel RD-1-specific skin test for the diagnosis of tuberculosis infection.

    PubMed

    Hoff, Soren T; Peter, Jonathan G; Theron, Grant; Pascoe, Mellissa; Tingskov, Pernille N; Aggerbeck, Henrik; Kolbus, Daniel; Ruhwald, Morten; Andersen, Peter; Dheda, Keertan

    2016-03-01

    C-Tb, a novel Mycobacterium tuberculosis and 6-kDa early secretory antigenic target/10-kDa culture filtrate protein (ESAT-6/CFP-10)-specific skin test, has high specificity in bacille Calmette-Guerin-vaccinated healthy controls. However, the sensitivity of C-Tb has hitherto not been determined. The objective was to determine the sensitivity of C-Tb in patients with active tuberculosis (TB) in comparison with the tuberculin skin test (TST) and QuantiFERON-TB Gold In-Tube (QFT-GIT).C-Tb and TST were randomly administered in a double-blinded fashion to one or the other forearm in 253 patients with active TB with or without HIV co-infection. QFT-GIT testing was performed prior to skin testing.Using a receiver operating characteristic curve-derived cut-point of 5 mm, C-Tb sensitivity was similar to QFT-GIT (73.9 (95% CI 67.8-79.3) versus 75.1 (95% CI 69.3-80.2)), and similar in HIV-infected and HIV-uninfected patients (76.7 (95% CI 69.0-83.3) versus 69.5 (95% CI 59.2-78.5)). However, sensitivity was significantly diminished in HIV-infected patients with CD4 counts <100 cells·mm(-3). C-Tb and QFT-GIT combined had significantly higher sensitivity than C-Tb alone (p<0.0001). C-Tb was safe with no significant adverse events. The 5 mm cut-point corresponded to that found in the previously published specificity study (TESEC-04).C-Tb has similar sensitivity compared with QFT-GIT for the diagnosis of M. tuberculosis infection. Sensitivity was reduced only in HIV-infected patients with severe immunosuppression. Further studies in different settings are required to validate the proposed 5 mm cut-point. PMID:26677940

  10. The Challenge of Producing Skin Test Antigens with Minimal Resources Suitable for Human Application against a Neglected Tropical Disease; Leprosy

    PubMed Central

    Rivoire, Becky L.; TerLouw, Stephen; Groathouse, Nathan A.; Brennan, Patrick J.

    2014-01-01

    True incidence of leprosy and its impact on transmission will not be understood until a tool is available to measure pre-symptomatic infection. Diagnosis of leprosy disease is currently based on clinical symptoms, which on average take 3–10 years to manifest. The fact that incidence, as defined by new case detection, equates with prevalence, i.e., registered cases, suggests that the cycle of transmission has not been fully intercepted by implementation of multiple drug therapy. This is supported by a high incidence of childhood leprosy. Epidemiological screening for pre-symptomatic leprosy in large endemic populations is required to facilitate targeted chemoprophylactic interventions. Such a test must be sensitive, specific, simple to administer, cost-effective, and easy to interpret. The intradermal skin test method that measures cell-mediated immunity was explored as the best option. Prior knowledge on skin testing of healthy subjects and leprosy patients with whole or partially fractionated Mycobacterium leprae bacilli, such as Lepromin or the Rees' or Convit' antigens, has established an acceptable safety and potency profile of these antigens. These data, along with immunoreactivity data, laid the foundation for two new leprosy skin test antigens, MLSA-LAM (M. leprae soluble antigen devoid of mycobacterial lipoglycans, primarily lipoarabinomannan) and MLCwA (M. leprae cell wall antigens). In the absence of commercial interest, the challenge was to develop these antigens under current good manufacturing practices in an acceptable local pilot facility and submit an Investigational New Drug to the Food and Drug Administration to allow a first-in-human phase I clinical trial. PMID:24874086

  11. The challenge of producing skin test antigens with minimal resources suitable for human application against a neglected tropical disease; leprosy.

    PubMed

    Rivoire, Becky L; TerLouw, Stephen; Groathouse, Nathan A; Brennan, Patrick J

    2014-01-01

    True incidence of leprosy and its impact on transmission will not be understood until a tool is available to measure pre-symptomatic infection. Diagnosis of leprosy disease is currently based on clinical symptoms, which on average take 3-10 years to manifest. The fact that incidence, as defined by new case detection, equates with prevalence, i.e., registered cases, suggests that the cycle of transmission has not been fully intercepted by implementation of multiple drug therapy. This is supported by a high incidence of childhood leprosy. Epidemiological screening for pre-symptomatic leprosy in large endemic populations is required to facilitate targeted chemoprophylactic interventions. Such a test must be sensitive, specific, simple to administer, cost-effective, and easy to interpret. The intradermal skin test method that measures cell-mediated immunity was explored as the best option. Prior knowledge on skin testing of healthy subjects and leprosy patients with whole or partially fractionated Mycobacterium leprae bacilli, such as Lepromin or the Rees' or Convit' antigens, has established an acceptable safety and potency profile of these antigens. These data, along with immunoreactivity data, laid the foundation for two new leprosy skin test antigens, MLSA-LAM (M. leprae soluble antigen devoid of mycobacterial lipoglycans, primarily lipoarabinomannan) and MLCwA (M. leprae cell wall antigens). In the absence of commercial interest, the challenge was to develop these antigens under current good manufacturing practices in an acceptable local pilot facility and submit an Investigational New Drug to the Food and Drug Administration to allow a first-in-human phase I clinical trial. PMID:24874086

  12. Tuberculin skin test and interferon-gamma release assay values are associated with antimicrobial peptides expression in  polymorphonuclear cells during latent tuberculous infection.

    PubMed

    Castañeda-Delgado, Julio E; Cervantes-Villagrana, Alberto; Serrano-Escobedo, Carmen J; Frausto-Lujan, Isabel; Rivas-Santiago, Cesar; Enciso-Moreno, Jose A; Rivas-Santiago, Bruno

    2014-06-01

    It has been reported that patients with progressive tuberculosis (TB) express abundant amounts of the antimicrobial peptides (AMPs) cathelicidin (LL-37) and human neutrophil peptide-1 (HNP-1) in circulating cells, whereas latent TB infected donors showed no differences when compared with purified protein derivative (PPD) and QuantiFERON®-TB Gold (QFT)-healthy individuals. The aim of this study was to determine whether LL-37 and HNP-1 production correlates with higher tuberculin skin test (TST) and QFT values in TB household contacts. Twenty-six TB household contact individuals between 26-58 years old TST and QFT positive with at last two years of latent TB infection were recruited. AMPs production by polymorphonuclear cells was determined by flow cytometry and correlation between TST and QFT values was analysed. Our results showed that there is a positive correlation between levels of HNP-1 and LL-37 production with reactivity to TST and/or QFT levels. This preliminary study suggests the potential use of the expression levels of these peptides as biomarkers for progression in latent infected individuals. PMID:24937049

  13. Tuberculin skin test and interferon-gamma release assay values are associated with antimicrobial peptides expression in  polymorphonuclear cells during latent tuberculous infection

    PubMed Central

    Castañeda-Delgado, Julio E; Cervantes-Villagrana, Alberto; Serrano-Escobedo, Carmen J; Frausto-Lujan, Isabel; Rivas-Santiago, Cesar; Enciso-Moreno, Jose A; Rivas-Santiago, Bruno

    2014-01-01

    It has been reported that patients with progressive tuberculosis (TB) express abundant amounts of the antimicrobial peptides (AMPs) cathelicidin (LL-37) and human neutrophil peptide-1 (HNP-1) in circulating cells, whereas latent TB infected donors showed no differences when compared with purified protein derivative (PPD) and QuantiFERON®-TB Gold (QFT)-healthy individuals. The aim of this study was to determine whether LL-37 and HNP-1 production correlates with higher tuberculin skin test (TST) and QFT values in TB household contacts. Twenty-six TB household contact individuals between 26-58 years old TST and QFT positive with at last two years of latent TB infection were recruited. AMPs production by polymorphonuclear cells was determined by flow cytometry and correlation between TST and QFT values was analysed. Our results showed that there is a positive correlation between levels of HNP-1 and LL-37 production with reactivity to TST and/or QFT levels. This preliminary study suggests the potential use of the expression levels of these peptides as biomarkers for progression in latent infected individuals. PMID:24937049

  14. Bayesian integrated testing strategy (ITS) for skin sensitization potency assessment: a decision support system for quantitative weight of evidence and adaptive testing strategy.

    PubMed

    Jaworska, Joanna S; Natsch, Andreas; Ryan, Cindy; Strickland, Judy; Ashikaga, Takao; Miyazawa, Masaaki

    2015-12-01

    The presented Bayesian network Integrated Testing Strategy (ITS-3) for skin sensitization potency assessment is a decision support system for a risk assessor that provides quantitative weight of evidence, leading to a mechanistically interpretable potency hypothesis, and formulates adaptive testing strategy for a chemical. The system was constructed with an aim to improve precision and accuracy for predicting LLNA potency beyond ITS-2 (Jaworska et al., J Appl Toxicol 33(11):1353-1364, 2013) by improving representation of chemistry and biology. Among novel elements are corrections for bioavailability both in vivo and in vitro as well as consideration of the individual assays' applicability domains in the prediction process. In ITS-3 structure, three validated alternative assays, DPRA, KeratinoSens and h-CLAT, represent first three key events of the adverse outcome pathway for skin sensitization. The skin sensitization potency prediction is provided as a probability distribution over four potency classes. The probability distribution is converted to Bayes factors to: 1) remove prediction bias introduced by the training set potency distribution and 2) express uncertainty in a quantitative manner, allowing transparent and consistent criteria to accept a prediction. The novel ITS-3 database includes 207 chemicals with a full set of in vivo and in vitro data. The accuracy for predicting LLNA outcomes on the external test set (n = 60) was as follows: hazard (two classes)-100 %, GHS potency classification (three classes)-96 %, potency (four classes)-89 %. This work demonstrates that skin sensitization potency prediction based on data from three key events, and often less, is possible, reliable over broad chemical classes and ready for practical applications. PMID:26612363

  15. Alkali-treated penicillin G solution is a better option than penicillin G as an alternative source of minor determinants for penicillin skin test.

    PubMed

    Wangrattanasopon, Pongsak; Ruxrungtham, Kiat; Chantaphakul, Hiroshi; Buranapraditkun, Supranee; Klaewsongkram, Jettanong

    2012-01-01

    Both benzylpenicilloyl-polylysine (PPL) and minor determinant mixture (MDM) are the recommended standard reagents for penicillin skin testing. However, penicillin G is commonly suggested as an alternative source of minor determinants. This study evaluated the accuracy of penicillin G and alkali-treated penicillin G compared with the standardized MDM for skin testing. Sixty-eight patients with histories of allergies to penicillin or semisynthetic penicillins were skin tested with commercial Kit penicillin allergenic determinants (DAP) (PPL and DAP-MDM; Diater Laboratorios, Madrid, Spain). The in-house MDM (IH-MDM), prepared by alkali-treated aged penicillin, and fresh penicillin G sodium (PGs) were tested alongside DAP-MDM. Positive penicillin skin test results were identified in 22 patients (32.4%) using commercial reagents (PPL+ DAP-MDM) and 19 of them reacted to DAP-MDM alone or together with PPL. The accuracy of IH-MDM and PGs compared with DAP-MDM was 89.7 and 76.5%, respectively. Our study shows that alkali-treated penicillin G is a better option than penicillin G as an alternative source of MDM for skin testing in case the commercialized MDM is not available. Minor determinants play a significant role for penicillin allergy in Thailand and should be included in the penicillin skin test panel to verify suspected cases of penicillin allergy. (ClinicalTrials.gov number: NCT00789217). PMID:22525392

  16. Multi-laboratory evaluation of SkinEthic HCE test method for testing serious eye damage/eye irritation using solid chemicals and overall performance of the test method with regard to solid and liquid chemicals testing.

    PubMed

    Alépée, N; Adriaens, E; Grandidier, M H; Meloni, M; Nardelli, L; Vinall, C J; Toner, F; Roper, C S; Van Rompay, A R; Leblanc, V; Cotovio, J

    2016-08-01

    A prospective multicentre study of the reconstructed human corneal epithelial tissue-based in vitro test method (SkinEthic™ HCE) was conducted to evaluate its usefulness to identify chemicals as either not classified for serious eye damage/eye irritation (No Cat.) or as classified (Cat. 1/Cat. 2) within UN GHS. The aim of this study was to demonstrate the transferability and reproducibility of the SkinEthic™ HCE EITS protocol for solids and define its predictive capacity. Briefly, 60 chemicals were three times tested (double blinded) in 3 laboratories and 35 additional chemicals were tested three times in one laboratory. Good within laboratory reproducibility was achieved of at least 95% (57/60) and 96.8% (92/95) for the extended data set. Furthermore, the overall concordance between the laboratories was 96.7% (58/60). The accuracy of the SkinEthic™ HCE EITS for the extended dataset, based on bootstrap resampling, was 81.0% (95% CI: 78.9% to 83.2%) with a sensitivity of 90.5% (95% CI: 88.1% to 92.9%) and specificity of 73.6% (95% CI: 71.7% to 75.5%). Overall, 200 chemicals were tested (105 liquids (EITL protocol) and 95 solids (EITS protocol)) resulting in a sensitivity of 95.2%, specificity of 72.1% and accuracy of 83.7%, thereby meeting all acceptance criteria for predictive capacity. PMID:26989001

  17. Effects of repeated administration of intradermal skin test by Mantoux method on delayed-type hypersensitivity responses in healthy young and elderly subjects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multi-test CMI to test immune response is no longer commercially available. DTH response is a highly suitable marker of immune function. Because delayed-type hypersensitivity (DTH) skin test can predict morbidity and mortality, it may be clinically meaningful test to evaluate the effect of nutrition...

  18. Chemical reactivity testing of optical fluids and materials in the DEIMOS spectrographic camera for the Keck II telescope

    NASA Astrophysics Data System (ADS)

    Hilyard, David F.; Laopodis, George K.; Faber, Sandra M.

    1999-09-01

    The DEIMOS Spectrograph Camera contains tow doublets and a triplet. Each group contains materials differing in thermal coefficient expansion, mechanical and optical properties. To mate the elements and at the same time accommodate large camera temperature changes, we will fill the space between with an optical fluid couplant. We selected candidate couplants, lens-support materials, and fluid-constraining materials based on published optical, mechanical and chemical properties. We then tested the chemical reactivity between the coupling fluids, lens-support and fluid- constraining materials. We describe here the test configurations, our criteria for reactivity, and the result for various test durations. We describe our conclusions and final choices for couplant and materials.

  19. Human Skin Aryl Hydrocarbon Hydroxylase

    PubMed Central

    Bickers, David R.; Kappas, Attallah

    1978-01-01

    Coal tar products, which are widely used in treating dermatologic disease, contain numerous polycyclic aromatic hydrocarbons, including 3,4-benzo[a]pyrene (BP). BP is among the most potent environmental chemical carcinogens and is known to evoke tumors in the skin of experimental animals and perhaps also of man. In this study the effect of cutaneous application of coal tar solution (U. S. Pharmacopeia) on aryl hydrocarbon hydroxylase (AHH) activity in the skin of patients usually treated with this drug was investigated. AHH, a cytochrome P-450 dependent carcinogen-metabolizing enzyme appears to play an important role in the activation of polycyclic hydrocarbons into reactive moieties that can bind to DNA and that may directly induce cancer. Application of coal tar solution to human skin caused a two to five-fold induction of cutaneous AHH in nine subjects. In further studies, the incubation of human skin with coal tar solution in vitro also caused variable induction of cutaneous AHH. Maximum responses in both systems occurred after 24 h and enzyme activity in vitro was time- and tissue- and substrate-concentration dependent. Studies in experimental animals showed that topical application of coal tar solution caused induction of AHH in skin and, after percutaneous absorption, in liver as well. Assay of several defined constituents of coal tar for AHH induction showed that BP was the most potent inducer of AHH tested. These studies indicate that topical application of coal tar solution in doses ordinarily used in treating dermatologic disease causes induction of AHH in human skin and suggest that such induced enzymatic activity could relate to carcinogenic responses to this agent in skin or, after percutaneous absorption, in other tissues as well. PMID:711851

  20. Skin Prick Test with Self-Saliva in Patients with Oral Aphthoses: A New Diagnostic Pathergy for Behcet’s Disease and Recurrent Aphthosis

    PubMed Central

    Togashi, Ari; Saito, Sanae; Kaneko, Fumio; Nakamura, Koichiro; Oyama, Noritaka

    2011-01-01

    There may be some difficulties to differentiate Behcet’s disease (BD), recurrent aphthosis (RA), and herpetic aphthous ulceration, from other mimicking oral disorders. Despite of unexpected sensitivity and responsiveness, the skin pathergy test regarding a non-specific hypersensitivity has long been thought as one of auxiliary diagnostic benefits for BD. To determine the potential usefulness and disease specificity of the prick reaction with saliva, a skin prick test with neat and filter-sterilized saliva was performed on the forearm skin of 26 individuals; 10 patients with BD (8 incomplete type without uveitis, 1 complete type, and 1 neurological type), 5 with RA, 3 with herpetic oral aphthosis, 2 with erythema nodosum alone, and 6 healthy controls. We assessed the skin reaction at 48 hours after pricking, and the pricked skin lesions were biopsied and analyzed immunohistologically. Nine of 10 BD patients (90 %) exhibited an indurative erythema at the skin site pricked with self-saliva, whereas 3 of 5 RA patients (60%) were relatively weak reaction. Pricking with filter-sterilized saliva failed to recapitulate any of positive skin reactions, albeit a faint erythematous dot appeared in a few BD patients, implicating the involvement of causative microorganism(s) in oral bacterial flora. Culture of saliva from 3 randomly chosen BD patients revealed numerous streptococcal colonies on Mitis-Salivarius agar. Histology of the pricked skin sites showed perivasucular inflammatory infiltrates, composed of CD4+ T cells and CD68+ monocyte/macrophage lineage, a feature consistent with a delayed type hypersensitive reaction. Our results suggested that skin prick test using self-saliva (a new diagnostic pathergy) can be a simple and valuable in vivo diagnostic approach for differentiating BD and RA from other mimicking mucocutaneous diseases. The positive skin prick may be triggered by resident intra-oral microflora, particularly streptococci, and may in part address the

  1. Skin prick test with self-saliva in patients with oral aphthoses: a diagnostic pathergy for Behcet's disease and recurrent aphthosis.

    PubMed

    Togashi, Ari; Saito, Sanae; Kaneko, Fumio; Nakamura, Koichiro; Oyama, Noritaka

    2011-06-01

    There may be some difficulties to differentiate Behcet's disease (BD), recurrent aphthosis (RA), and herpetic aphthous ulceration, from other mimicking oral disorders. Despite of unexpected sensitivity and responsiveness, the skin pathergy test regarding a non specific hypersensitivity has long been thought as one of auxiliary diagnostic benefits for BD. To determine the potential usefulness and disease specificity of the prick reaction with saliva, a skin prick test with neat and filter-sterilized saliva was performed on the forearm skin of 26 individuals; 10 patients with BD (8 incomplete type without uveitis, 1 complete type, and 1 neurological type), 5 with RA, 3 with herpetic oral aphthosis, 2 with erythema nodosum alone, and 6 healthy controls. We assessed the skin reaction at 48 hours after pricking, and the pricked skin lesions were biopsied and analyzed immunohistologically. Nine of 10 BD patients (90 %) exhibited an indurative erythema at the skin site pricked with self-saliva, whereas 3 of 5 RA patients (60%) were relatively weak reaction. Pricking with filter-sterilized saliva failed to recapitulate any of positive skin reactions, albeit a faint erythematous dot appeared in a few BD patients, implicating the involvement of causative microorganism(s) in oral bacterial flora. Culture of saliva from 3 randomly chosen BD patients revealed numerous streptococcal colonies on Mitis-Salivarius agar. Histology of the pricked skin sites showed perivascular inflammatory infiltrates, composed of CD4+ T cells and CD68+ monocyte/macrophage lineage, a feature consistent with a delayed type hypersensitive reaction. Our results suggested that skin prick test using self-saliva (a new diagnostic pathergy) can be a simple and valuable in vivo diagnostic approach for differentiating BD and RA from other mimicking mucocutaneous diseases. The positive skin prick may be triggered by resident intra-oral microflora, particularly streptococci, and may in part address the

  2. Use of a smart phone based thermo camera for skin prick allergy testing: a feasibility study (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Barla, Lindi; Verdaasdonk, Rudolf M.; Rustemeyer, Thomas; Klaessens, John; van der Veen, Albert

    2016-02-01

    Allergy testing is usually performed by exposing the skin to small quantities of potential allergens on the inner forearm and scratching the protective epidermis to increase exposure. After 15 minutes the dermatologist performs a visual check for swelling and erythema which is subjective and difficult for e.g. dark skin types. A small smart phone based thermo camera (FLIR One) was used to obtain quantitative images in a feasibility study of 17 patients Directly after allergen exposure on the forearm, thermal images were captured at 30 seconds interval and processed to a time lapse movie over 15 minutes. Considering the 'subjective' reading of the dermatologist as golden standard, in 11/17 pts (65%) the evaluation of dermatologist was confirmed by the thermo camera including 5 of 6 patients without allergic response. In 7 patients thermo showed additional spots. Of the 342 sites tested, the dermatologist detected 47 allergies of which 28 (60%) were confirmed by thermo imaging while thermo imaging showed 12 additional spots. The method can be improved with user dedicated acquisition software and better registration between normal and thermal images. The lymphatic reaction seems to shift from the original puncture site. The interpretation of the thermal images is still subjective since collecting quantitative data is difficult due to motion patient during 15 minutes. Although not yet conclusive, thermal imaging shows to be promising to improve the sensitivity and selectivity of allergy testing using a smart phone based camera.

  3. The Spanish standard patch test series: 2016 update by the Spanish Contact Dermatitis and Skin Allergy Research Group (GEIDAC).

    PubMed

    Hervella-Garcés, M; García-Gavín, J; Silvestre-Salvador, J F

    2016-09-01

    The Spanish standard patch test series, as recommended by the Spanish Contact Dermatitis and Skin Allergy Research Group (GEIDAC), has been updated for 2016. The new series replaces the 2012 version and contains the minimum set of allergens recommended for routine investigation of contact allergy in Spain from 2016 onwards. Four haptens -clioquinol, thimerosal, mercury, and primin- have been eliminated owing to a low frequency of relevant allergic reactions, while 3 new allergens -methylisothiazolinone, diazolidinyl urea, and imidazolidinyl urea- have been added. GEIDAC has also modified the recommended aqueous solution concentrations for the 2 classic, major haptens methylchloroisothiazolinone and methylisothiazolinone, which are now to be tested at 200ppm in aqueous solution, and formaldehyde, which is now to be tested in a 2% aqueous solution. Updating the Spanish standard series is one of the functions of GEIDAC, which is responsible for ensuring that the standard series is suited to the country's epidemiological profile and pattern of contact sensitization. PMID:27262363

  4. An in vitro skin irritation test (SIT) using the EpiDerm reconstructed human epidermal (RHE) model.

    PubMed

    Kandárová, Helena; Hayden, Patrick; Klausner, Mitchell; Kubilus, Joseph; Sheasgreen, John

    2009-01-01

    The EpiDerm Skin Irritation test (EpiDerm SIT) was developed and validated for in vitro skin irritation testing of chemicals, including cosmetic and pharmaceutical ingredients. The EpiDerm SIT utilizes the 3D in vitro reconstructed human epidermal (RHE) model EpiDerm. The procedure described in this protocol allows for discrimination between irritants of GHS category 2 and non-irritants. The test is performed over the course of a 4 day time period, consisting of pre-incubation, 60 minute exposure, 42 hour post-incubation and MTT viability assay. After tissue receipt and overnight pre-incubation (Day 0), tissues are topically exposed to the test chemicals (Day 1), which can be liquid, semisolid, solid or waxy. Three tissues are used for each test chemical, as well as for the positive control (5% aq. SDS solution), and a negative control (DPBS). Chemical exposure lasts for 60 minutes, 35 min of which the tissues are kept in an incubator at 37 degrees C. The test substances are then removed from the tissue surface by an extensive washing procedure. The tissue inserts are blotted and transferred to fresh medium. After a 24 hr incubation period (Day 2), the medium is exchanged. The medium can be saved for further analysis of cytokines or other endpoints of interest. After the medium exchange, tissues are incubated for an additional 18 hours. At the end of the entire 42 h post-incubation (day 3), the tissues are transferred into yellow MTT solution and incubated for 3 hours. The resultant purple-blue formazan salt, formed mainly by mitochondrial metabolism, is extracted for 2 hours using isopropanol. The optical density of the extracted formazan is determined using a spectrophotometer. A chemical is classified as an irritant if the tissue viability relative to the negative control treated tissues is reduced below 50%. This procedure can be used as full replacement of the in vivo rabbit skin irritation test for hazard identification and labeling of chemicals in line with

  5. Testing single extraction methods and in vitro tests to assess the geochemical reactivity and human bioaccessibility of silver in urban soils amended with silver nanoparticles.

    PubMed

    Cruz, N; Rodrigues, S M; Tavares, D; Monteiro, R J R; Carvalho, L; Trindade, T; Duarte, A C; Pereira, E; Römkens, Paul F A M

    2015-09-01

    To assess if the geochemical reactivity and human bioaccessibility of silver nanoparticles (AgNPs) in soils can be determined by routine soil tests commonly applied to other metals in soil, colloidal Ag was introduced to five pots containing urban soils (equivalent to 6.8 mg Ag kg(-1) soil). Following a 45 days stabilization period, the geochemical reactivity was determined by extraction using 0.43 M and 2 M HNO3. The bioaccessibility of AgNPs was evaluated using the Simplified Bioaccessibility Extraction Test (SBET) the "Unified BARGE Method" (UBM), and two simulated lung fluids (modified Gamble's solution (MGS) and artificial lysosomal fluid (ALF)). The amount of Ag extracted by 0.43 M and 2 M HNO3 soil tests was <8% and <50%, respectively of the total amount of Ag added to soils suggesting that the reactivity of Ag present in the soil can be relatively low. The bioaccessibility of Ag as determined by the four in vitro tests ranged from 17% (ALF extraction) to 99% (SBET) indicating that almost all Ag can be released from soil due to specific interactions with the organic ligands present in the simulated body fluids. This study shows that to develop sound soil risk evaluations regarding soil contamination with AgNPs, aspects of Ag biochemistry need to be considered, particularly when linking commonly applied soil tests to human risk assessment. PMID:25966049

  6. Feed-forward active contour analysis for improved brachial artery reactivity testing.

    PubMed

    Pugliese, Daniel N; Sehgal, Chandra M; Sultan, Laith R; Reamer, Courtney B; Mohler, Emile R

    2016-08-01

    The object of this study was to utilize a novel feed-forward active contour (FFAC) algorithm to find a reproducible technique for analysis of brachial artery reactivity. Flow-mediated dilation (FMD) is an important marker of vascular endothelial function but has not been adopted for widespread clinical use given its technical limitations, including inter-observer variability and differences in technique across clinical sites. We developed a novel FFAC algorithm with the goal of validating a more reliable standard. Forty-six healthy volunteers underwent FMD measurement according to the standard technique. Ultrasound videos lasting 5-10 seconds each were obtained pre-cuff inflation and at minutes 1 through 5 post-cuff deflation in longitudinal and transverse views. Automated segmentation using the FFAC algorithm with initial boundary definition from three different observers was used to analyze the images to measure diameter/cross-sectional area over the cardiac cycle. The %FMD was calculated for average, minimum, and maximum diameters/areas. Using the FFAC algorithm, the population-specific coefficient of variation (CV) at end-diastole was 3.24% for transverse compared to 9.96% for longitudinal measurements; the subject-specific CV was 15.03% compared to 57.41%, respectively. For longitudinal measurements made via the conventional method, the population-specific CV was 4.77% and subject-specific CV was 117.79%. The intraclass correlation coefficient (ICC) for transverse measurements was 0.97 (95% CI: 0.95-0.98) compared to 0.90 (95% CI: 0.84-0.94) for longitudinal measurements with FFAC and 0.72 (95% CI: 0.51-0.84) for conventional measurements. In conclusion, transverse views using the novel FFAC method provide less inter-observer variability than traditional longitudinal views. Improved reproducibility may allow adoption of FMD testing in a clinical setting. The FFAC algorithm is a robust technique that should be evaluated further for its ability to replace the

  7. The effects of serial skin testing with purified protein derivative on the level and quality of antibodies to complex and defined antigens in Mycobacterium bovis-infected cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several serologic tests designed to detect antibodies to immunodominant Mycobacterium bovis antigens have recently emerged as ancillary tests for the detection of bovine tuberculosis in cattle, particularly when applied after injection of purified protein derivative (PPD) for skin test that signific...

  8. The genetics of skin, hair, and eye color variation and its relevance to forensic pigmentation predictive tests.

    PubMed

    Maroñas, O; Söchtig, J; Ruiz, Y; Phillips, C; Carracedo, Á; Lareu, M V

    2015-01-01

    This review examines the potential application of single nucleotide polymorphism (SNP)-based predictive tests for skin, hair, and eye color to forensic analysis in support of police investigations lacking DNA database matches or eyewitness testimony. Brief descriptions of the biology of melanogenesis and the main genes involved are presented in order to understand the basis of common pigmentation variation in humans. We outline the most recently developed forensically sensitive multiplex tests that can be applied to investigative analyses. The review also describes the biology of the SNPs with the closest associations to, and therefore the best predictors for, common variation in eye, hair, and skin pigmentation. Because pigmentation pathways are complex in their patterns, many of the better-studied human albinism traits provide insight into how pigmentation SNPs interact, control, or modify gene expression and show varying degrees of association with the key genes identified to date. These aspects of SNP action are discussed in an overview of each of the functional groups of pigmentation genes. PMID:26227136

  9. A paired comparison of tuberculin skin test results in health care workers using 5 TU and 10 TU tuberculin

    PubMed Central

    Stuart, R.; Bennett, N.; Forbes, A.; Grayson, M

    2000-01-01

    BACKGROUND—Historically, 10 TU has been employed in Australia and the United Kingdom to perform the tuberculin skin test (TST). However, this makes it difficult to compare the rates of TST positivity with other countries such as the USA who use 5 TU. To assess the impact of the dose of tuberculin on the TST a comparison was made of TST responses in health care workers given a TST with both 5 and 10 TU.
METHODS—Two TSTs were performed simultaneously in each health care worker using 5 and 10 TU. Each dose was randomly assigned in a blinded manner to the right or left forearm and read at 48-72 hours by a single nurse who was blinded to the assignment of the 5 and 10 TU doses.
RESULTS—A total of 128 health care workers were enrolled, 119 (93%) of whom had a past history of BCG vaccination. The overall mean difference in paired reaction sizes for the two doses was 1.5 mm with 95% limits of agreement of -3.6 to 6.5 mm.
CONCLUSION—A slightly larger TST reading was seen with 10 TU than with 5 TU. The mean difference of 1.5 mm between the two doses should be considered when comparing rates of TST positivity between countries who use different doses of tuberculin to perform the tuberculin skin test.

 PMID:10899248

  10. Food allergy and cross-reactivity-chickpea as a test case.

    PubMed

    Bar-El Dadon, Shimrit; Pascual, Cristina Y; Reifen, Ram

    2014-12-15

    Chickpea has become one of the most abundant crops consumed in the Mediterranean and also in western world. Chickpea allergy is reported in specific geographic areas and is associated with lentil and/or pea allergy. We investigated cross-reactivity between chickpea and pea/lentil/soybean/hazelnut. The IgE-binding profiles of chickpea globulin and pea/lentil/soybean/hazelnut extracts were analyzed by immunoblotting and immunoblot-inhibition studies. Inhibition-assay with pea/lentil completely suppressed IgE-binding to chickpea globulin allergens, while not so in the reciprocal inhibition. Pre-absorption of sera with chickpea globulin caused the disappearance of IgE-binding to protein on an immunoblot of soybean/hazelnut protein extract. These results suggest that cross-reactivity exists between chickpea and pea/lentil/soybean/hazelnut. Chickpea allergy is associated with lentil and/or pea allergy, but evidently may not present independently. This, together with the described asymmetric cross-reactivity and phylogenetic aspects, suggest that chickpea allergy is merely an expression of cross-reactivity, caused by pea and/or lentil as the "primary" allergen. PMID:25038702

  11. In chemico evaluation of tea tree essential oils as skin sensitizers. Impact of the chemical composition on aging and generation of reactive species.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tea tree oil (TTO) is a popular skin remedy obtained from the leaves of Melaleuca alternifolia, M. linariifolia or M dissitiflora. Due to the commercial importance ofTTO, substitution or adulteration with other tea tree species (such as cajeput, niaouli, manuka and kanuka oils) is common and may p...

  12. Evaluation of distal symmetric polyneuropathy: the role of autonomic testing, nerve biopsy, and skin biopsy (an evidence-based review).

    PubMed

    England, J D; Gronseth, G S; Franklin, G; Carter, G T; Kinsella, L J; Cohen, J A; Asbury, A K; Szigeti, K; Lupski, J R; Latov, N; Lewis, R A; Low, P A; Fisher, M A; Herrmann, D; Howard, J F; Lauria, G; Miller, R G; Polydefkis, M; Sumner, A J

    2009-01-01

    Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of autonomic testing, nerve biopsy, and skin biopsy for the assessment of polyneuropathy. A literature review using MEDLINE, EMBASE, Science Citation Index, and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based on the level of evidence. (1) Autonomic testing may be considered in the evaluation of patients with polyneuropathy to document autonomic nervous system dysfunction (Level B). Such testing should be considered especially for the evaluation of suspected autonomic neuropathy (Level B) and distal small fiber sensory polyneuropathy (SFSN) (Level C). A battery of validated tests is recommended to achieve the highest diagnostic accuracy (Level B). (2) Nerve biopsy is generally accepted as useful in the evaluation of certain neuropathies as in patients with suspected amyloid neuropathy, mononeuropathy multiplex due to vasculitis, or with atypical forms of chronic inflammatory demyelinating polyneuropathy (CIDP). However, the literature is insufficient to provide a recommendation regarding when a nerve biopsy may be useful in the evaluation of DSP (Level U). (3) Skin biopsy is a validated technique for determining intraepidermal nerve fiber (IENF) density and may be considered for the diagnosis of DSP, particularly SFSN (Level C). There is a need for additional prospective studies to define more exact guidelines for the evaluation of polyneuropathy. PMID:19086069

  13. Eosinophilic airway disease in a patient with a negative skin prick test, but a positive patch test with platinum salts--implications for medical surveillance.

    PubMed

    Merget, Rolf; Fartasch, Manigé; Sander, Ingrid; Van Kampen, Vera; Raulf, Monika; Brüning, Thomas

    2015-09-01

    We present the case of a 52-year-old woman with a topic dermatitis since adolescence who developed work-related hand eczema, cough and runny nose 12 years after she had started working as a laboratory technician at a precious metals refinery. While skin prick test with sodium hexachloroplatinate (SPTPt ) was negative, patch testing with ammonium tetrachloroplatinate was positive after 24, 48, 72, and 96 hr. Inhalation challenge with sodium hexachloroplatinate yielded cough, mild shortness of breath, and a maximal decrease of FEV1 of 8% from baseline 24 hr after the challenge. Significant increases of bronchial hyperresponsiveness, exhaled nitric monoxide and sputum eosinophils were documented after the challenge. We conclude that eosinophilic airway disease due to platinum salts may occur in SPTPt negative subjects. Both, patch testing and inhalation challenge with platinum salts should be considered in SPT negative subjects with occupational exposure to precious metal salts and work-related allergic symptoms. PMID:26010732

  14. Reactivity worth of gas expansion modules (GEMs) in the fast flux test facility

    SciTech Connect

    Campbell, L.R.; Nelson, J.V.; Burke, T.M.; Rawlins, J.A.; Daughtry, J.W.; Bennett, R.A.

    1986-01-01

    A new passive shutdown device called a gas expansion module (GEM) has been developed at Hanford Engineering Development Laboratory to insert negative reactivity during a primary system loss of flow in a liquid-metal reactor (LMR). A GEM is a hollow removable core component which is sealed at the top and open at the bottom. An argon gas bubble trapped inside the assembly expands when core inlet pressure decreases (caused by a flow reduction) and expels sodium from the assembly. The GEMs are designed so that the level of the liquid-sodium primary system coolant within a GEM is above the top of the core when the primary pumps are operating at full flow and is below the bottom of the core when the primary pumps are off. When a GEM is placed at the boundary of the core and radial reflector, the drop in sodium level increases core neutron leakage and inserts negative reactivity. The results of these measurements confirm the effectiveness of GEMs in adding negative reactivity in loss-of-flow situations. It follows, therefore, that the inherent safety of LMRs, comparable in size to the FFTF, can be enhanced by the use of GEMs.

  15. Physiological Reactivity in a Community Sample of Sexually Aggressive Young Men: A Test of Competing Hypotheses

    PubMed Central

    Peterson, Zoë D.; Janssen, Erick; Goodrich, David; Heiman, Julia R.

    2015-01-01

    Men’s sexually aggressive behavior potentially could relate to either physiological hyporeactivity or hyperreactivity, and these two different physiological profiles could be associated with different underlying causes of sexual aggression. Thus, measurement of physiological reactivity could provide insight into mechanisms relevant to the etiology of sexual aggression. The relationship between sexual aggression and physiological reactivity was investigated in 78 community men (38 sexually aggressive and 40 non-aggressive men). In a laboratory protocol, the men were exposed to neutral, negative-affect-inducing, and positive-affect-inducing stimuli. Men’s salivary cortisol concentrations and electrodermal activity (EDA) were measured throughout the laboratory procedure. Sexually aggressive men demonstrated (1) lower overall cortisol levels and (2) lower EDA reactivity in some conditions as compared to non-aggressive men. Results of this study were consistent with the idea that men’s sexual aggression is associated with physiological hyporeactivity, a physiological profile that has been found to be associated with externalizing behaviors and psychopathic traits. PMID:24310818

  16. Verification Of Residual Strength Properties From Compression After Impact Tests On Thin CFRP Skin, A1 Honeycomb Composites

    NASA Astrophysics Data System (ADS)

    Kalnins, Kaspars; Graham, Adrian J.; Sinnema, Gerben

    2012-07-01

    This article presents a study of CFRP/Al honeycomb panels subjected to a low velocity impact which, as a result, caused strength reduction. The main scope of the current study was to investigate experimental procedures, which are not well standardized and later verify them with numerical simulations. To ensure integrity of typical lightweight structural panels of modern spacecraft, knowledge about the impact energy required to produce clearly visible damage, and the resulting strength degradation is of high importance. For this initial investigation, Readily available ‘heritage’ (1980s) sandwich structure with relatively thin skin was used for this investigation. After initial attempts to produce impact damage, it was decided to create quasistatic indentation instead of low velocity impact, to cause barely visible damage. Forty two edgewise Compressions After Impact (CAI) test specimens have been produced and tested up to failure, while recording the strain distribution by optical means during the tests. Ultrasonic C-scan inspection was used to identify the damage evolution before and after each test. The optical strain measurements acquired during the tests showed sensitivity level capable to track the local buckling of damaged region.

  17. Comparative Study of Positive Versus Negative Autologous Serum Skin Test in Chronic Spontaneous Urticaria and its Treatment Outcome

    PubMed Central

    Kumar, Yadalla Hari Kishan; Bhaskar, Sapnashree; Shankar, Keerthi

    2016-01-01

    Background: Chronic urticaria (CU) is defined as urticaria persisting daily or almost daily for more than 6 weeks and affecting 0.1% of the population. Mast cell degranulation and histamine release are of central importance in the pathogenesis of CU. About 40-50% of the patients with chronic idiopathic urticaria (CIU) or chronic spontaneous urticaria (CSU) demonstrates an immediate wheal and flare response to intradermal injected autologous serum. This led to the concept of autoimmune urticaria (AIU). Aims: To determine the occurrence, clinical features, associated clinical conditions, comorbidities of AIU, and to compare this with CSU. This study aimed to find the frequency of autologous serum skin test (ASST)-positive patients among patients with CSU and to identify the clinical and laboratory parameters associated with positive ASST and to compare the treatment outcome. Materials and Methods: A prospective correlation study in 110 patients with CSU was conducted, after screening 200 CU patients attending the outpatient Department of Dermatology during from January 2012 to May 2013. Patients were subjected to ASST, complete blood counts, urine routine examination, liver function tests, renal function tests, thyroid function tests (T3, T4, and TSH), and urine analysis. Results: Out of 200 CU patients screened, 90 patients had excludable causes based on detailed history and skin prick test, and the remaining 110 patients were considered to have CSU. These 110 patients were further subjected to ASST, serum immunoglobulin E (IgE), and peripheral blood eosinophilia. ASST was positive in 48 patients and negative in 62 patients. Frequency of urticarial attacks and associated diseases such as abnormal thyroid function tests in both ASST-positive and ASST-negative patients did not show any statistical significance. Only attacks of angioedema in ASST-positive individuals were higher and were statistically significant. In the ASST-positive group, 31 (81.25%) patients showed

  18. Skin capacitance imaging and corneosurfametry. A comparative assessment of the impact of surfactants on stratum corneum.

    PubMed

    Xhauflaire-Uhoda, Emmanuelle; Loussouarn, Geneviève; Haubrechts, Christelle; Léger, Didier Saint; Piérard, Gérald E

    2006-05-01

    Silicon image sensor (SIS) technology was recently introduced as an innovative tool (SkinChip, L'Oréal) providing sensitive imaging of the skin capacitance. This method can detect discrete focal variations in skin surface hydration, and thus early discrete manifestations of skin irritation induced by surfactants. In the present in vivo study, 2 neat and diluted shampoos, and 5% and 10% sodium laurylsulfate solutions were tested on human skin. Each surfactant solution was gently rubbed on the skin using wet hair wicks mimicking the casual use of a shampoo on the scalp. Clinical and SIS evaluations were carried out. In addition, the same products were tested using the ex vivo corneosurfametry bioassay performed on human stratum corneum (SC) harvested by cyanoacrylate skin surface strippings. The colourimetric index of mildness (CIM) was measured on these samples. The product reactivity with the SC was recognized by darker skin capacitance images, and by both lowered SkinChip-generated values and lowered CIM values. The extent in changes varied according to the nature of the test products and their concentrations. The SkinChip image changes likely corresponded to the acute surfactant-induced water swelling of the corneocytes. Skin capacitance imaging and corneosurfametry allow to disclose discrete surfactant-induced alterations of corneocytes. PMID:16689808

  19. Strategic use of serology for the diagnosis of bovine tuberculosis after intradermal skin testing.

    PubMed

    Casal, Carmen; Díez-Guerrier, Alberto; Álvarez, Julio; Rodriguez-Campos, Sabrina; Mateos, Ana; Linscott, Richard; Martel, Edmond; Lawrence, John C; Whelan, Clare; Clarke, John; O'Brien, Amanda; Domínguez, Lucas; Aranaz, Alicia

    2014-06-01

    Diagnostic tests based on cell-mediated immunity are used in programmes for eradication of bovine tuberculosis (Mycobacterium bovis). Serological assays could be applied as ancillary methods to detect infected animals. Our objective was to evaluate two serological techniques: M. bovis Ab Test (IDEXX, USA) and Enferplex™ TB assay (Enfer, Ireland) in animals tested simultaneously with the single and comparative intradermal tests and the interferon-gamma assay. This work was performed at two stages. First, a preliminary panel of samples collected prior to intradermal tests from tuberculosis-free (n=60) and M. bovis-infected herds (n=78) was assayed, obtaining high specificity: 100% (M. bovis Ab Test) and 98.3% (Enferplex TB assay) but low sensitivity (detection of M. bovis infected animals): 23.9% (M. bovis Ab Test) and 32.6% (Enferplex TB assay). Subsequently, the use of serological techniques was further studied in two herds with M. bovis infection (n=77) using samples collected prior to, and 72 h and 15 days after PPD inoculation. The highest level of detection of infected animals for serology was achieved at 15 days post-intradermal tests taking advantage of the anamnestic effect: 70.4% and 85.2% in herd A, and 66.7% and 83.3% in herd B, using M. bovis Ab Test and Enferplex TB assay, respectively. Quantitative results (average values obtained with M. bovis Ab Test ELISA and degree of positivity obtained with Enferplex TB assay) were higher in animals showing lesions compatible with tuberculosis. No significant differences were observed in the number of confirmed infected animals detected with either serological technique. PMID:24679958

  20. [Improvement of skin moisture and skin texture with urea therapy].

    PubMed

    Puschmann, M; Gogoll, K

    1989-01-01

    A significant increase in skin moisture and an improvement in skin smoothness after application of a urea-containing cream was noticed in a large number of volunteers with healthy skin and in neurodermitis patients compared with untreated skin and with vehicle. The effect was shown after one application (short-term test) as well as after repeated application (long-term test). Regular application of preparation containing urea increases the moisture of a the skin and improves the skin's smoothness compared with its previous condition, with untreated skin, and with placebo preparations. PMID:2807927

  1. Skin test and Gamma Interferon enzyme-linked Immunosorbent assay results in Sheep exposed to dead Mycobacterium avium subspecies paratuberculosis Organisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cell mediated immunity (CMI) diagnostic tests, such as the gamma interferon enzyme-linked immunosorbent assay (IFN-gamma ELISA) and the johnin skin test, have the potential to detect animals infected with Mycobacterium avium subspecies paratuberculosis (MAP) early in the course of the disease. While...

  2. Average Skin-Friction Drag Coefficients from Tank Tests of a Parabolic Body of Revolution (NACA RM-10)

    NASA Technical Reports Server (NTRS)

    Mottard, Elmo J; Loposer, J Dan

    1954-01-01

    Average skin-friction drag coefficients were obtained from boundary-layer total-pressure measurements on a parabolic body of revolution (NACA rm-10, basic fineness ratio 15) in water at Reynolds numbers from 4.4 x 10(6) to 70 x 10(6). The tests were made in the Langley tank no. 1 with the body sting-mounted at a depth of two maximum body diameters. The arithmetic mean of three drag measurements taken around the body was in good agreement with flat-plate results, but, apparently because of the slight surface wave caused by the body, the distribution of the boundary layer around the body was not uniform over part of the Reynolds number range.

  3. Association between HLA-DR4 haplotypes and tuberculin skin test response in the Aché population.

    PubMed

    Lindenau, J D; Guimarães, L S P; Hurtado, A M; Hill, K R; Tsuneto, L T; Salzano, F M; Petzl-Erler, M L; Hutz, M H

    2014-11-01

    The human leukocyte antigen (HLA) system has a major role in the regulation of the immune response as it is involved in the defense against pathogens. Evidence for association with tuberculosis (TB) is more consistent for class II than for class I HLA genes. TB is important among indigenous peoples in South America, not only because of its historical role in regional depopulation, but also because it is still widespread. The aim of this study was to evaluate the association of HLA class II alleles, haplotypes and genotypes and tuberculin skin test response (TST) in 76 individuals of the Aché population. Poisson Regression was employed to assess risk genotypes. DRB1*04, DQA1*03 and DQB1*03:02 were associated with TST response in this population. PMID:25329634

  4. Monitoring changes in the scattering properties of mouse skin with optical coherence tomography during an in vivo glucose tolerance test

    NASA Astrophysics Data System (ADS)

    Kinnunen, M.; Tausta, S.; Myllylä, R.; Vainio, S.

    2007-05-01

    A non-invasive glucose monitoring technique would make evaluation of blood glucose values easier and more convenient. This would help diabetic patients to control their blood glucose values more regularly. A few years ago optical coherence tomography (OCT) was proposed as a non-invasive sensor for monitoring changes in blood glucose concentration. The method is based on monitoring glucose-induced changes in the scattering properties of the target. This article describes how OCT was used to monitor changes in the scattering properties of mouse skin during an in vivo glucose tolerance test. The results show that OCT has the potential to register glucose-induced changes in the optical properties of the sample. However, a commercial OCT device with a probe designed for imaging is not very suitable for non-invasive monitoring of glucose-induced changes in scattering. The problems confronted in this study, possibly originating from the small size of the animals, are discussed in the article.

  5. Testing a family intervention hypothesis: the contribution of mother-infant skin-to-skin contact (kangaroo care) to family interaction, proximity, and touch.

    PubMed

    Feldman, Ruth; Weller, Aron; Sirota, Lea; Eidelman, Arthur I

    2003-03-01

    The provision of maternal-infant body contact during a period of maternal separation was examined for its effects on parent-infant and triadic interactions. Participants were 146 three-month-old preterm infants and their parents, half of whom received skin-to-skin contact, or kangaroo care (KC), in the neonatal nursery. Global relational style and micro-patterns of proximity and touch were coded. Following KC, mothers and fathers were more sensitive and less intrusive, infants showed less negative affect, and family style was more cohesive. Among KC families, maternal and paternal affectionate touch of infant and spouse was more frequent, spouses remained in closer proximity, and infant proximity position was conducive to mutual gaze and touch during triadic play. The role of touch as a constituent of the co-regulatory parent-infant and triadic systems and the effects of maternal contact on mothering, co-parenting, and family processes are discussed. PMID:12666466

  6. Critical experiment tests of bowing and expansion reactivity calculations for LMRS

    SciTech Connect

    Schaefer, R.W.

    1988-01-01

    Experiments done in several LMR-type critical assemblies simulated core axial expansion, core radial expansion and bowing, coolant expansion, and control driveline expansion. For the most part new experimental techniques were developed to do these experiments. Calculations of the experiments basically used design-level methods, except when it was necessary to investigate complexities peculiar to the experiments. It was found that these feedback reactivities generally are overpredicted, but the predictions are within 30% of the experimental values. 14 refs., 2 figs., 4 tabs.

  7. Two novel prediction models improve predictions of skin corrosive sub-categories by test methods of OECD Test Guideline No. 431.

    PubMed

    Desprez, Bertrand; Barroso, João; Griesinger, Claudius; Kandárová, Helena; Alépée, Nathalie; Fuchs, Horst W

    2015-12-01

    Alternative test methods often use prediction models (PMs) for converting endpoint measurements into predictions. Two PMs are used for the skin corrosion tests (SCTs) of the OECD Test Guideline No. 431 (TG 431). One is specific to EpiSkin™ test method, whereas EpiDerm™, SkinEthic™ RHE and epiCS® share a common PM. These methods are based on reconstructed human epidermis models wherein cell viability values are measured. Their PMs allow translating those values into sub-categories of corrosive chemicals, Category 1A (Cat1A) and a combination of Categories 1B/1C (Cat1BC), and identifying non-corrosive (NC) chemicals. EpiSkin™'s PM already results in sufficiently accurate predictions. The common PM of the three others accurately identifies all corrosive chemicals but, for sub-categorization, an important fraction of Cat1BC chemicals (40-50%) is over-predicted as Cat1A. This paper presents a post-hoc analysis of validation data on a set of n=80 chemicals. It investigates: why this common PM causes these over-predictions and how two novel PMs that we developed (PMvar1 and PMvar2) improve the predictive capacity of these methods. PMvar1 is based on a two-step approach; PMvar2 is based on a single composite indicator of cell viability. Both showed a greater capacity to predict Cat1BC, while Cat1A correct predictions remaining at least at the same level of EpiSkin™. We suggest revising TG 431, to include the novel PMs in view of improving the predictive capacity of its SCTs. PMID:26320836

  8. LGIT In Vitro Latency Model in Primary and T Cell Lines to Test HIV-1 Reactivation Compounds.

    PubMed

    Jung, Ulrike; Takahashi, Mayumi; Rossi, John J; Burnett, John C

    2016-01-01

    Persistent latent HIV-1 reservoirs pose a major barrier for combinatorial antiretroviral therapy (cART) to achieve eradication of the virus. A variety of mechanisms likely contribute to HIV-1 persistence, including establishment of post-integration latency in resting CD4+ T-lymphocytes, the proliferation of these latently infected cells, and the induced or spontaneous reactivation of latent virus. To elucidate the mechanisms of latency and to investigate therapeutic strategies for reactivating and purging the latent reservoir, investigators have developed in vitro models of HIV-1 latency using primary CD4+ T-lymphocytes and CD4+ T-cell lines. Several types of in vitro latency models range from replication-competent to single-round, replication-deficient viruses exhibiting different degrees of viral genomic deletion. Working under the hypothesis that HIV-1 post-integration latency is directly linked to HIV-1 promoter activity, which can be obscured by additional proteins expressed during replication, we focus here on the creation of latently infected primary human T-cells and cell lines through the single-round, replication deficient HIV-1 LGIT model. In this model the long terminal repeat (LTR) of the HIV-1 virus drives a cassette of GFP-IRES-Tat that allows testing of reactivating components and initiates a positive feedback loop through Tat expression. PMID:26714717

  9. Usefulness of the rK39-Immunochromatographic Test, Direct Agglutination Test, and Leishmanin Skin Test for Detecting Asymptomatic Leishmania Infection in Children in a New Visceral Leishmaniasis Focus in Amhara State, Ethiopia

    PubMed Central

    Gadisa, Endalamaw; Custodio, Estefanía; Cañavate, Carmen; Sordo, Luis; Abebe, Zelalem; Nieto, Javier; Chicharro, Carmen; Aseffa, Abraham; Yamuah, Lawrence; Engers, Howard; Moreno, Javier; Cruz, Israel

    2012-01-01

    In areas where visceral leishmaniasis is anthroponotic, asymptomatically infected patients may play a role in transmission. Additionally, the number of asymptomatic patients in a disease-endemic area will also provide information on transmission dynamics. Libo Kemkem and Fogera districts (Amhara State, Ethiopia) are now considered newly established areas to which visceral leishmaniasis is endemic. In selected villages in these districts, we conducted a study to assess the usefulness of different approaches to estimate the asymptomatic infection rate. Of 605 participants, the rK39 immunochromatographic test was able to detect asymptomatic infection in 1.5% (9 of 605), direct agglutination test in 5.3% (32 of 605), and leishmanin skin test in 5.6% (33 of 589); the combined use of serologic methods and leishmanin skin test enabled detecting asymptomatic infection in 10.1% (61 of 605). We conclude that the best option to detect asymptomatic infection in this new visceral leishmaniasis–endemic focus is the combined use of the direct agglutination test and the leishmanin skin test. PMID:22556076

  10. Catch-up validation study of an in vitro skin irritation test method based on an open source reconstructed epidermis (phase II).

    PubMed

    Groeber, F; Schober, L; Schmid, F F; Traube, A; Kolbus-Hernandez, S; Daton, K; Hoffmann, S; Petersohn, D; Schäfer-Korting, M; Walles, H; Mewes, K R

    2016-10-01

    To replace the Draize skin irritation assay (OECD guideline 404) several test methods based on reconstructed human epidermis (RHE) have been developed and were adopted in the OECD test guideline 439. However, all validated test methods in the guideline are linked to RHE provided by only three companies. Thus, the availability of these test models is dependent on the commercial interest of the producer. To overcome this limitation and thus to increase the accessibility of in vitro skin irritation testing, an open source reconstructed epidermis (OS-REp) was introduced. To demonstrate the capacity of the OS-REp in regulatory risk assessment, a catch-up validation study was performed. The participating laboratories used in-house generated OS-REp to assess the set of 20 reference substances according to the performance standards amending the OECD test guideline 439. Testing was performed under blinded conditions. The within-laboratory reproducibility of 87% and the inter-laboratory reproducibility of 85% prove a high reliability of irritancy testing using the OS-REp protocol. In addition, the prediction capacity was with an accuracy of 80% comparable to previous published RHE based test protocols. Taken together the results indicate that the OS-REp test method can be used as a standalone alternative skin irritation test replacing the OECD test guideline 404. PMID:27435616

  11. A Review of Serological Tests to Assist Diagnosis of Reactive Arthritis: Critical Appraisal on Methodologies

    PubMed Central

    Tuuminen, Tamara; Lounamo, Kari; Leirisalo-Repo, Marjatta

    2013-01-01

    On a population-based level, the incidence of reactive arthritis (ReA) is 0.6–27/100,000. The definition of ReA varies and its pathogenesis is not yet clear. Attempts in basic immunology to suggest hypotheses for proliferation of forbidden B cell clones, molecular mimicry, and involvement of cross-reactive antibodies are helpful but not sufficient. Importantly, for the clinical diagnosis of the preceding infection, serology is widely used. Unfortunately, the accuracy of associations between serologic findings and clinical conclusions is plagued by poor standardization of methods. So far, few attempts have been done to examine the pitfalls of different approaches. Here, we review several serologic techniques, their performance and limitations. We will focus on serology for Yersinia, Campylobacter, Salmonella, Shigella, and Chlamydia trachomatis because these bacteria have a longer history of being associated with ReA. We also address controversies regarding the role of serology for some other bacteria linked to autoimmune disorders. PMID:24363655

  12. 3,3'-Dihydroxyisorenieratene prevents UV-induced formation of reactive oxygen species and the release of protein-bound zinc ions in human skin fibroblasts.

    PubMed

    Lutter, Kaya; De Spirt, Silke; Kock, Sebastian; Kröncke, Klaus-Dietrich; Martin, Hans-Dieter; Wagener, Tanja; Stahl, Wilhelm

    2010-02-01

    3,3'-Dihydroxyisorenieratene (DHIR) is a structurally unusual carotenoid exhibiting bifunctional antioxidant properties. It is synthesized by Brevibacterium linens, used in dairy industry for the production of red smear cheeses. The compound protects cellular structures against photo-oxidative damage and inhibits the UV-dependent formation of thymidine dimers. Here we show that DHIR prevents a UV-induced intracellular release of zinc ions from proteins in human dermal fibroblasts. The effect is correlated with a decreased formation of intracellular reactive oxygen species. In contrast, zinc release from cellular proteins induced by hyperthermia is not affected by pretreatment of cells with the antioxidant DHIR. It is suggested that the intracellular zinc release upon UV irradiation is due to oxidative modifications of the zinc ligands in proteins (e.g. cysteine) and that protection by DHIR is due to intracellular scavenging of reactive oxygen species generated in photo-oxidation. PMID:19862772

  13. Quantifying and Addressing the DOE Material Reactivity Requirements with Analysis and Testing of Hydrogen Storage Materials & Systems

    SciTech Connect

    Khalil, Y. F

    2015-01-05

    The objective of this project is to examine safety aspects of candidate hydrogen storage materials and systems being developed in the DOE Hydrogen Program. As a result of this effort, the general DOE safety target will be given useful meaning by establishing a link between the characteristics of new storage materials and the satisfaction of safety criteria. This will be accomplished through the development and application of formal risk analysis methods, standardized materials testing, chemical reactivity characterization, novel risk mitigation approaches and subscale system demonstration. The project also will collaborate with other DOE and international activities in materials based hydrogen storage safety to provide a larger, highly coordinated effort.

  14. Determination of the axial and circumferential mechanical properties of the skin tissue using experimental testing and constitutive modeling.

    PubMed

    Karimi, Alireza; Navidbakhsh, Mahdi; Haghighatnama, Maedeh; Haghi, Afsaneh Motevalli

    2015-01-01

    The skin, being a multi-layered material, is responsible for protecting the human body from the mechanical, bacterial, and viral insults. The skin tissue may display different mechanical properties according to the anatomical locations of a body. However, these mechanical properties in different anatomical regions and at different loading directions (axial and circumferential) of the mice body to date have not been determined. In this study, the axial and circumferential loads were imposed on the mice skin samples. The elastic modulus and maximum stress of the skin tissues were measured before the failure occurred. The nonlinear mechanical behavior of the skin tissues was also computationally investigated through a suitable constitutive equation. Hyperelastic material model was calibrated using the experimental data. Regardless of the anatomic locations of the mice body, the results revealed significantly different mechanical properties in the axial and circumferential directions and, consequently, the mice skin tissue behaves like a pure anisotropic material. The highest elastic modulus was observed in the back skin under the circumferential direction (6.67 MPa), while the lowest one was seen in the abdomen skin under circumferential loading (0.80 MPa). The Ogden material model was narrowly captured the nonlinear mechanical response of the skin at different loading directions. The results help to understand the isotropic/anisotropic mechanical behavior of the skin tissue at different anatomical locations. They also have implications for a diversity of disciplines, i.e., dermatology, cosmetics industry, clinical decision making, and clinical intervention. PMID:25266627

  15. Bovine Tuberculosis: Effect of the Tuberculin Skin Test on the Interferon Gamma Assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction Bovine tuberculosis (bTB) is a disease of zoonotic and economic importance. Despite intensive eradication efforts over decades, bTB continues to be a problem with global perspective. The control of bTB is based on a test and slaughter policy and/or abattoir surveillance. Two types of tu...

  16. Effect of skin test on serum antibody responses to Mycobacterium bovis infection in cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, several serologic tests designed to detect immunodominant antibodies to M. bovis antigens (e.g., MPB83, MPB70, ESAT-6, and CFP10) have emerged for potential use with samples from cattle. Of these, a commercial ELISA to MPB83/MPB70 (M. bovis antibody ELISA) has gained approval for use in ca...

  17. Skin Cancer

    MedlinePlus

    ... are specialized skin cells that produce pigment called melanin. The melanin pigment produced by melanocytes gives skin its color. ... absorbing and scattering the energy. People with more melanin have darker skin and better protection from UV ...

  18. Skin Conditions

    MedlinePlus

    Your skin is your body's largest organ. It covers and protects your body. Your skin Holds body fluids in, preventing dehydration Keeps harmful ... it Anything that irritates, clogs, or inflames your skin can cause symptoms such as redness, swelling, burning, ...

  19. Coseismic landslide reactivation characteristics determined from dynamic ring-shear testing

    USGS Publications Warehouse

    Schulz, William H.; Wang, Gonghui; Zhang, Fanyu

    2012-01-01

    Large earthquakes often cause widespread landsliding that alters landscapes and presents significant hazards to human safety and the built environment. For example, the 2008, Mw 7.9 Wenchuan, China earthquake triggered more than 56,000 landslides that killed about 20,000 people. Predicting the occurrence and nature of coseismic landslides remains elusive largely because limitations on laboratory apparatus and a lack of instrumental field observations have precluded understanding the basic response of geologic materials to seismically induced shearing. Coastal Oregon, USA is a region of numerous landslides and great subduction-zone earthquakes that recur every 300-500 yrs, the most recent of which occurred during January 1700. Reactivation of existing landslides during future great earthquakes could threaten human safety because many of these slides potentially impact tsunami evacuation and emergency response routes.

  20. Screening Test for Shed Skin Cells by Measuring the Ratio of Human DNA to Staphylococcus epidermidis DNA.

    PubMed

    Nakanishi, Hiroaki; Ohmori, Takeshi; Hara, Masaaki; Takahashi, Shirushi; Kurosu, Akira; Takada, Aya; Saito, Kazuyuki

    2016-05-01

    A novel screening method for shed skin cells by detecting Staphylococcus epidermidis (S. epidermidis), which is a resident bacterium on skin, was developed. Staphylococcus epidermidis was detected using real-time PCR. Staphylococcus epidermidis was detected in all 20 human skin surface samples. Although not present in blood and urine samples, S. epidermidis was detected in 6 of 20 saliva samples, and 5 of 18 semen samples. The ratio of human DNA to S. epidermidisDNA was significantly smaller in human skin surface samples than in saliva and semen samples in which S. epidermidis was detected. Therefore, although skin cells could not be identified by detecting only S. epidermidis, they could be distinguished by measuring the S. epidermidis to human DNA ratio. This method could be applied to casework touch samples, which suggests that it is useful for screening whether skin cells and human DNA are present on potential evidentiary touch samples. PMID:27122397

  1. Diagnostic efficacy of in vitro methods vs. skin testing in patients with inhalant allergies

    SciTech Connect

    Corey, J.P.; Liudahl, J.J.; Young, S.A.; Rodman, S.M. )

    1991-03-01

    The purpose of our study was to investigate the diagnostic efficacy of two selected methods of in vitro allergy testing. Specifically, the PRIST/modified RAST I125 isotope systems and the Quantizyme/modified EAST alkaline phosphatase method were compared. The time, expense, convenience, and diagnostic efficacy of the two procedures are discussed. Special attention is given to the practicality of each method for the practicing physician.

  2. CO2CRC's Otway Residual Saturation and Dissolution Test: Using Reactive Ester Tracers to Determine Residual CO2 Saturation

    NASA Astrophysics Data System (ADS)

    Myers, M.; Stalker, L.; LaForce, T.; Pejcic, B.; Dyt, C.; Ho, K.; Ennis-King, J.

    2013-12-01

    Residual trapping, that is CO2 held in the rock pore space due to capillarity, is an important storage mechanism in geo-sequestration of over the short to medium term (up to 1000 years). As such residual CO2 saturation is a critical reservoir parameter for assessing the storage capacity and security of carbon capture and storage (CCS). As a component of the CO2CRC's Residual Gas Saturation and Dissolution Test at the CO2CRC Otway Project site in Victoria (Australia), we have recently tested a suite of reactive esters (triacetin, tripropionin and propylene glycol diacetate) in a single well chemical tracer test to determine residual CO2 saturation. The goal of this project was to assess and validate a suite of possible tests that could be implemented to determine residual CO2 saturation. For this test, the chemical tracers were injected with a saturated CO2/water mixture into the formation (that is already at residual CO2 saturation) where they were allowed to 'soak' for approximately 10 days allowing for the partial hydrolysis of the esters to their corresponding carboxylic acids and alcohols. Water containing the tracers was then produced from the well resulting in over 600 tracer samples over a period of 12 hours. A selection of these samples were analysed for tracer content and to establish tracer breakthrough curves. To understand the behaviour of these chemical tracers in the downhole environment containing residually trapped supercritical CO2 and formation water, it is necessary to determine the supercritical CO2/water partition coefficients. We have previously determined these in the laboratory (Myers et al., 2012) and they are used here to model the tracer behaviour and provide an estimate of the residual CO2 saturation. Two different computational simulators were used to analyse the tracer breakthrough profiles. The first is based on simple chromatographic retardation and has been used extensively in single well chemical tracer tests to determine residual

  3. Cryotherapy - skin

    MedlinePlus

    Cryosurgery - skin; Warts - freezing; Warts - cryotherapy ... Cryotherapy or cryosurgery may be used to: Remove warts Destroy precancerous skin lesions (actinic keratoses or solar keratoses) In rare cases, ...

  4. External validity of Concealed Information Test experiment: Comparison of respiration, skin conductance, and heart rate between experimental and field card tests.

    PubMed

    Zaitsu, Wataru

    2016-07-01

    The Concealed Information Test (CIT) is a memory detection method based on an examinee's physiological responses to crime-relevant items (critical items) in comparison with crime-irrelevant items (noncritical items). I examined the external validity of CIT laboratory experiments by comparing respiratory speed (RS), skin conductance response (SCR), and heart rate (HR) between a laboratory experiment (n = 30) and a field test (n = 30) in a card test. A linear mixed models analysis showed that the critical items in both CIT contexts elicited CIT effects: RS repression, SCR increase, and HR deceleration. Additionally, the critical items in the field elicited a larger RS suppression than those in the laboratory; however, SCR and HR on the critical items showed no statistical differences between the laboratory and field CITs. Moreover, the tonic HRs in the field tests were higher than in the CIT experiments, but there were no significant correlations between the tonic HR and each CIT effect in RS, SCR, and HR. These results suggested that CIT detection efficiency was not affected by arousal levels and may imply that the CIT effects observed with RS, SCR, and HR in the CIT laboratory experiments has adequate external validity and can be generalized to the CIT field. PMID:27031043

  5. Integrated decision strategies for skin sensitization hazard.

    PubMed

    Strickland, Judy; Zang, Qingda; Kleinstreuer, Nicole; Paris, Michael; Lehmann, David M; Choksi, Neepa; Matheson, Joanna; Jacobs, Abigail; Lowit, Anna; Allen, David; Casey, Warren

    2016-09-01

    One of the top priorities of the Interagency Coordinating Committee for the Validation of Alternative Methods (ICCVAM) is the identification and evaluation of non-animal alternatives for skin sensitization testing. Although skin sensitization is a complex process, the key biological events of the process have been well characterized in an adverse outcome pathway (AOP) proposed by the Organisation for Economic Co-operation and Development (OECD). Accordingly, ICCVAM is working to develop integrated decision strategies based on the AOP using in vitro, in chemico and in silico information. Data were compiled for 120 substances tested in the murine local lymph node assay (LLNA), direct peptide reactivity assay (DPRA), human cell line activation test (h-CLAT) and KeratinoSens assay. Data for six physicochemical properties, which may affect skin penetration, were also collected, and skin sensitization read-across predictions were performed using OECD QSAR Toolbox. All data were combined into a variety of potential integrated decision strategies to predict LLNA outcomes using a training set of 94 substances and an external test set of 26 substances. Fifty-four models were built using multiple combinations of machine learning approaches and predictor variables. The seven models with the highest accuracy (89-96% for the test set and 96-99% for the training set) for predicting LLNA outcomes used a support vector machine (SVM) approach with different combinations of predictor variables. The performance statistics of the SVM models were higher than any of the non-animal tests alone and higher than simple test battery approaches using these methods. These data suggest that computational approaches are promising tools to effectively integrate data sources to identify potential skin sensitizers without animal testing. Published 2016. This article has been contributed to by US Government employees and their work is in the public domain in the USA. PMID:26851134

  6. Guidance on the Stand Down, Mothball, and Reactivation of Ground Test Facilities

    NASA Technical Reports Server (NTRS)

    Volkman, Gregrey T.; Dunn, Steven C.

    2013-01-01

    The development of aerospace and aeronautics products typically requires three distinct types of testing resources across research, development, test, and evaluation: experimental ground testing, computational "testing" and development, and flight testing. Over the last twenty plus years, computational methods have replaced some physical experiments and this trend is continuing. The result is decreased utilization of ground test capabilities and, along with market forces, industry consolidation, and other factors, has resulted in the stand down and oftentimes closure of many ground test facilities. Ground test capabilities are (and very likely will continue to be for many years) required to verify computational results and to provide information for regimes where computational methods remain immature. Ground test capabilities are very costly to build and to maintain, so once constructed and operational it may be desirable to retain access to those capabilities even if not currently needed. One means of doing this while reducing ongoing sustainment costs is to stand down the facility into a "mothball" status - keeping it alive to bring it back when needed. Both NASA and the US Department of Defense have policies to accomplish the mothball of a facility, but with little detail. This paper offers a generic process to follow that can be tailored based on the needs of the owner and the applicable facility.

  7. Randomized Clinical Trial of the Innovative Bilayered Wound Dressing Made of Silk and Gelatin: Safety and Efficacy Tests Using a Split-Thickness Skin Graft Model

    PubMed Central

    Hasatsri, Sukhontha; Angspatt, Apichai; Aramwit, Pornanong

    2015-01-01

    We developed the novel silk fibroin-based bilayered wound dressing for the treatment of partial thickness wounds. And it showed relevant characteristics and accelerated the healing of full-thickness wounds in a rat model. This study is the clinical evaluation of the bilayered wound dressing to confirm its safety and efficacy for the treatment of split-thickness skin donor sites. The safety test was performed using a patch model and no evidence of marked and severe cutaneous reactions was found. The efficacy test of the bilayered wound dressing was conducted on 23 patients with 30 split-thickness skin graft donor sites to evaluate healing time, pain score, skin barrier function, and systemic reaction in comparison to Bactigras. We found that the healing time of donor site wounds treated with the bilayered wound dressing (11 ± 6 days) was significantly faster than those treated with Bactigras (14 ± 6 days) (p = 10−6). The wound sites treated with the bilayered wound dressing showed significantly less pain and more rapid skin functional barrier recovery than those treated with Bactigras (p = 10−5). Therefore, these results confirmed the clinical safety and efficacy of the bilayered wound dressing for the treatment of split-thickness skin graft donor sites. PMID:26221170

  8. Test of carcinogenicity in mouse skin: Methylenedianiline,. gamma. glycidyloxytrimethyloxysilane,. gamma. aminopropyltriethoxysilane and a mixture of m-phenylenediamine, methylenedianiline, and diglycidylether of bisphenol-A

    SciTech Connect

    Holland, J.M.; Smith, L.H.; Frome, E.; Whitaker, M.J.; Gipson, L.C.; Fry, R.J.M.

    1987-06-01

    Application of graded concentrations of four test substances in acetone to the skin of C3H mice five times a week resulted in the following: ..gamma..aminopropyltriethoxysilane at concentration of 100 and 50 wt/vol % was a severe and mild skin irritant in female C3Hf/Bd respectively and in males a mild skin irritant. Methylenedianiline at a concentration of 10 wt/vol % in methanol killed 4/9 females and 1/9 males. When acetone was the solvent 3/10 females and 3/10 males died within 2 weeks. No mortality or skin damage occurred with ..gamma..glycidyloxytrimethyloxysilane or the mixture of m-phenylenediamine, methylenedianiline and diglycidylether of bisphenol A (MDA). A study of the effects of a two-year, three times a week, topical application of the four test materials revealed no significant increase in skin tumors. The incidence of liver tumors appeared to be increased by exposure to methylenedianiline and with the mixture (MDA). Significant and dose-dependent increases in mortality were found in male mice with MDA and increased mortality at the highest dose (10.8 mg/week) in females. In the case of methylenedianiline excess mortality was found in both sexes. The precise cause of excess mortality from dermal absorption of the materials applied over a two-year period was not established. 5 refs., 12 figs., 12 tabs.

  9. Correlation between skin prick test using commercial extract of cow's milk protein and fresh milk and food challenges.

    PubMed

    Calvani, Mauro; Mauro, Calvani; Alessandri, Claudia; Claudia, Alessandri; Frediani, Tullio; Tullio, Frediani; Lucarelli, Sandra; Sandra, Lucarelli; Miceli Sopo, Stefano; Stefano, Miceli Sopo; Panetta, Valentina; Valentina, Panetta; Zappalã, Daniela; Daniela, Zappala'; Zicari, Anna Maria; Maria, Zicari Anna

    2007-11-01

    The skin prick test (SPT) is regarded as an important diagnostic measure in the diagnostic work-up of cow's milk protein allergy. It is not known whether commercial extracts have any advantage over fresh milk. The aims of the study were to (i) compare the diagnostic capacity of SPTs for the three main cow's milk proteins (alpha-lactalbumin, casein and beta-lactoglobulin) with fresh milk and (ii) determine a cut-off that discriminates between allergic and tolerant children in a controlled food challenge. A study was carried out on 104 children consecutively attending two paediatric allergy clinics for suspected cow's milk allergy. A clinical history, SPTs with fresh cow's milk and commercial extracts of its three main proteins and a challenge test were performed on all the children. A study of the validity of the prick test was also performed by taking different cut-off points for fresh milk and its proteins. Twenty-eight of 104 challenge tests (26.9%) were positive. At a cut-off point of 3 mm, fresh milk showed the greatest negative predictive value (98%), whereas casein showed the greatest positive predictive value (PPV, 85%). Calculation of 95% predicted probabilities using logistic regression revealed predictive decision points of 12 mm for lactalbumin, 9 mm for casein, 10 mm for beta-lactoglobulin and 15 mm for fresh cow's milk. We found that the greater the number of positive SPTs for milk proteins, the more likely the positive response to challenge. Having a positive SPT for all three milk proteins had PPV of 92.3% and would seem more clinically useful than any cut-off. Both fresh milk and cow's milk extract of the three main proteins could be useful in the diagnostic work-up of cow's milk allergy. Finding positivity to all three cow's milk proteins seems to be a simpler and more useful way of avoiding oral food challenges. PMID:18001429

  10. A genomic biomarker signature can predict skin sensitizers using a cell-based in vitro alternative to animal tests

    PubMed Central

    2011-01-01

    Background Allergic contact dermatitis is an inflammatory skin disease that affects a significant proportion of the population. This disease is caused by an adverse immune response towards chemical haptens, and leads to a substantial economic burden for society. Current test of sensitizing chemicals rely on animal experimentation. New legislations on the registration and use of chemicals within pharmaceutical and cosmetic industries have stimulated significant research efforts to develop alternative, human cell-based assays for the prediction of sensitization. The aim is to replace animal experiments with in vitro tests displaying a higher predictive power. Results We have developed a novel cell-based assay for the prediction of sensitizing chemicals. By analyzing the transcriptome of the human cell line MUTZ-3 after 24 h stimulation, using 20 different sensitizing chemicals, 20 non-sensitizing chemicals and vehicle controls, we have identified a biomarker signature of 200 genes with potent discriminatory ability. Using a Support Vector Machine for supervised classification, the prediction performance of the assay revealed an area under the ROC curve of 0.98. In addition, categorizing the chemicals according to the LLNA assay, this gene signature could also predict sensitizing potency. The identified markers are involved in biological pathways with immunological relevant functions, which can shed light on the process of human sensitization. Conclusions A gene signature predicting sensitization, using a human cell line in vitro, has been identified. This simple and robust cell-based assay has the potential to completely replace or drastically reduce the utilization of test systems based on experimental animals. Being based on human biology, the assay is proposed to be more accurate for predicting sensitization in humans, than the traditional animal-based tests. PMID:21824406

  11. Skin sensitization of epoxyaldehydes: importance of conjugation.

    PubMed

    Delaine, Tamara; Hagvall, Lina; Rudbäck, Johanna; Luthman, Kristina; Karlberg, Ann-Therese

    2013-05-20

    Structure-activity relationship (SAR) models are important tools for predicting the skin sensitization potential of new compounds without animal testing. In compounds possessing a structural alert (aldehyde) and an activation alert (double bond), it is important to consider bioactivation/autoxidation (e.g., epoxidation). In the present study, we have explored a series of aldehydes with regard to contact allergy. The chemical reactivity of these 6 aldehydes toward a model hexapeptide was investigated, and their skin sensitization potencies were evaluated using the local lymph node assay (LLNA). Overall, we observed a similar trend for the in vitro reactivity and the in vivo sensitization potency for the structural analogues in this study. The highly reactive conjugated aldehydes (α,β-unsaturated aldehydes and 2,3-epoxyaldehydes) are sensitizing moieties, while nonconjugated aldehydes and nonterminal aliphatic epoxides show low reactivity and low sensitization potency. Our data show the importance of not only double bond conjugation to aldehyde but also epoxide-aldehyde conjugation. The observations indicate that the formation of nonconjugated epoxides by bioactivation or autoxidation is not sufficient to significantly increase the sensitization potency of weakly sensitizing parent compounds. PMID:23534857

  12. Absorption of ethanol, acetone, benzene and 1,2-dichloroethane through human skin in vitro: a test of diffusion model predictions

    SciTech Connect

    Gajjar, Rachna M.; Kasting, Gerald B.

    2014-11-15

    The overall goal of this research was to further develop and improve an existing skin diffusion model by experimentally confirming the predicted absorption rates of topically-applied volatile organic compounds (VOCs) based on their physicochemical properties, the skin surface temperature, and the wind velocity. In vitro human skin permeation of two hydrophilic solvents (acetone and ethanol) and two lipophilic solvents (benzene and 1,2-dichloroethane) was studied in Franz cells placed in a fume hood. Four doses of each {sup 14}C-radiolabed compound were tested — 5, 10, 20, and 40 μL cm{sup −2}, corresponding to specific doses ranging in mass from 5.0 to 63 mg cm{sup −2}. The maximum percentage of radiolabel absorbed into the receptor solutions for all test conditions was 0.3%. Although the absolute absorption of each solvent increased with dose, percentage absorption decreased. This decrease was consistent with the concept of a stratum corneum deposition region, which traps small amounts of solvent in the upper skin layers, decreasing the evaporation rate. The diffusion model satisfactorily described the cumulative absorption of ethanol; however, values for the other VOCs were underpredicted in a manner related to their ability to disrupt or solubilize skin lipids. In order to more closely describe the permeation data, significant increases in the stratum corneum/water partition coefficients, K{sub sc}, and modest changes to the diffusion coefficients, D{sub sc}, were required. The analysis provided strong evidence for both skin swelling and barrier disruption by VOCs, even by the minute amounts absorbed under these in vitro test conditions. - Highlights: • Human skin absorption of small doses of VOCs was measured in vitro in a fume hood. • The VOCs tested were ethanol, acetone, benzene and 1,2-dichloroethane. • Fraction of dose absorbed for all compounds at all doses tested was less than 0.3%. • The more aggressive VOCs absorbed at higher levels than

  13. Chromium and reactive element modified aluminide diffusion coatings on superalloys - Environmental testing

    NASA Technical Reports Server (NTRS)

    Bianco, Robert; Rapp, Robert A.; Smialek, James L.

    1993-01-01

    The high temperature performance of reactive element (RE)-doped and Cr/RE-modified aluminide diffusion coatings on commercial Ni-base alloy substrates was determined. In isothermal oxidation at 1100 C in air, RE-doped aluminide coatings on IN 713LC substrates formed a continuous slow-growing n-Al2O3 scale after 44 hrs of exposure. The coatings were protected by either an outer ridge Al2O3 scale with an inner compact Al2O3 scale rich in RE or by a continuous compact scale without any noticeable cracks or flaws. The cyclic oxidation behavior of Cr/RE-modified aluminide coatings on Rene 80 and IN 713LC alloys and of RE-doped aluminide coatings on IN 713LC alloys at 1100 C in static air was determined. Pack powder entrapment from the powder contacting (PC) process detracted significantly from the overall cyclic oxidation performance. Type I hot corrosion behavior of Cr/RE-modified aluminide coatings on Rene 80 and Mar-M247 alloy substrates at 900 C in a catalyzed 0.1 percent SO3/O3 gas mixture was determined. The modified coatings produced from the PC arrangement provided significantly better resistance to hot corrosion attack than commercial low-activity aluminide coatings produced by the above pack arrangement.

  14. A test of the facultative calibration/reactive heritability model of extraversion

    PubMed Central

    Haysom, Hannah J.; Mitchem, Dorian G.; Lee, Anthony J.; Wright, Margaret J.; Martin, Nicholas G.; Keller, Matthew C.; Zietsch, Brendan P.

    2015-01-01

    A model proposed by Lukaszewski and Roney (2011) suggests that each individual’s level of extraversion is calibrated to other traits that predict the success of an extraverted behavioural strategy. Under ‘facultative calibration’, extraversion is not directly heritable, but rather exhibits heritability through its calibration to directly heritable traits (“reactive heritability”). The current study uses biometrical modelling of 1659 identical and non-identical twins and their siblings to assess whether the genetic variation in extraversion is calibrated to variation in facial attractiveness, intelligence, height in men and body mass index (BMI) in women. Extraversion was significantly positively correlated with facial attractiveness in both males (r=.11) and females (r=.18), but correlations between extraversion and the other variables were not consistent with predictions. Further, twin modelling revealed that the genetic variation in facial attractiveness did not account for a substantial proportion of the variation in extraversion in either males (2.4%) or females (0.5%). PMID:26880866

  15. Specificity of the Tuberculin Skin Test and the T-SPOT."TB" Assay among Students in a Low-Tuberculosis Incidence Setting

    ERIC Educational Resources Information Center

    Talbot, Elizabeth A.; Harland, Dawn; Wieland-Alter, Wendy; Burrer, Sherry; Adams, Lisa V.

    2012-01-01

    Objective: Interferon-[gamma] release assays (IGRAs) are an important tool for detecting latent "Mycobacterium tuberculosis" infection (LTBI). Insufficient data exist about IGRA specificity in college health centers, most of which screen students for LTBI using the tuberculin skin test (TST). Participants: Students at a low-TB incidence college…

  16. IDENTIFICATION OF DIFFERENCES IN THE PROTEIN CONTENT OF MYCOBACTERIUM AVIUM SUBSPECIES PARATUBERCULOSIS PURIFIED PROTEIN DERIVATIVE PREPARATIONS WITH DIFFERENT SKIN TEST SPECIFICITIES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycobacterium avium subspecies paratuberculosis (Map) strain ATCC 19698 has been used to produce a purified protein derivative (PPD) that can be utilized as a diagnostic reagent. Two Map PPD lots (Johnin 9801 and Johnin 0202) were used to skin test sheep and cattle for exposure to Map. Johnin 980...

  17. Comparison of QuantiFERON-TB gold in tube test versus tuberculin skin test for screening of latent tuberculosis infection in Saudi Arabia: A population-based study

    PubMed Central

    Balkhy, Hanan H.; El Beltagy, Kamel; El-Saed, Aiman; Aljasir, Badr; Althaqafi, Abdulhakeem; Alothman, Adel F.; Alshalaan, Mohammad; Al-Jahdali, Hamdan

    2016-01-01

    OBJECTIVES: To compare QuantiFERON-TB gold in tube (QFT-GIT) test with tuberculin skin test (TST) in detecting latent tuberculosis infection (LTBI) among a general population in Saudi Arabia. METHODS: A population-based cross-sectional study was conducted between July 2010 and March 2013 among individuals randomly selected from the list of those receiving care at primary healthcare centers in three provinces of Saudi Arabia; Central, Western, and Eastern provinces. Those younger than 5 years, immunocompromised, had a current or previous history of active TB, LTBI, or who were receiving anti-TB medications were excluded. Informed consent was obtained before the study questionnaire was completed. Participants were then evaluated for LTBI using QFT-GIT test followed immediately by TST. RESULTS: Of the 1369 subjects included in the final analysis, QFT-GIT was positive in 124 (9.1%) and TST was positive in 127 (9.3%). Positive concordance was observed in 49 (3.6%) subjects while negative concordance was observed in 1167 (85.2%) subjects. The overall agreement between the two tests was 88.8% with a significant kappa (κ) test (κ = 0.332, P < 0.001). Concordance was significantly higher in younger age, female gender, single status, students, primary education, living in middle-sized families, and never smoked. CONCLUSIONS: The overall agreement of TST and QFT-GIT for the detection of LTBI among a Saudi general population was 88.8%. QFT-GIT is probably comparable to TST for detecting LTBI in an intermediate TB burden country with high at birth bacille calmette guerin vaccination coverage. Further prospective studies are needed to compare the ability of both tests to predict TB disease. PMID:27512509

  18. Neurological Complications of VZV Reactivation

    PubMed Central

    Nagel, Maria A.

    2014-01-01

    Purpose of the review Varicella zoster virus (VZV) reactivation results in zoster, which may be complicated by postherpetic neuralgia, myelitis, meningoencephalitis and VZV vasculopathy. This review highlights the clinical features, laboratory abnormalities, imaging changes and optimal treatment of each of those conditions. Because all of these neurological disorders produced by VZV reactivation can occur in the absence of rash, the virological tests proving that VZV caused disease are discussed. Recent findings After primary infection, VZV becomes latent in ganglionic neurons along the entire neuraxis. With a decline in VZV-specific cell-mediated immunity, VZV reactivates from ganglia and travels anterograde to the skin to cause zoster, which is often complicated by postherpetic neuralgia. VZV can also travel retrograde to produce meningoencephaltis, myelitis and stroke. When these complications occur without rash, VZV-induced disease can be diagnosed by detection of VZV DNA or anti-VZV antibody in CSF and treated with intravenous acyclovir. Summary Awareness of the expanding spectrum of neurological complications caused by VZV reactivation with and without rash will improve diagnosis and treatment. PMID:24792344

  19. Usefulness of C-reactive protein testing in acute cough/respiratory tract infection: an open cluster-randomized clinical trial with C-reactive protein testing in the intervention group

    PubMed Central

    2014-01-01

    Background Point of care testing for C-reactive protein (CRP) has shown promise as a measure to reduce unnecessary antibiotic prescribing in respiratory tract infections (RTI), but its use in primary care is still controversial. We aimed to evaluate the effect of CRP testing on the prescription of antibiotics, referral for radiography, and the outcome of patients in general practice with acute cough/RTI. Methods An open-cluster randomized clinical trial was conducted, with CRP testing performed in the intervention group. Antibiotic prescribing and referral for radiography were the main outcome measures. Results A total of 179 patients were included: 101 in the intervention group and 78 in the control group. The two groups were similar in clinical characteristics. In the intervention group, the antibiotic prescribing rate was 37.6%, which was significantly lower than that in the control group (58.9%) (P = 0.006). Referral for chest X-ray was also significantly lower in the intervention group (55.4%) than in the control group (75.6%) (P = 0.004). The recovery rate, as recorded by the GPs, was 92.9% and 93.6% in the intervention and control groups, respectively. Conclusion The study showed that CRP testing in patients with acute cough/RTI may reduce antibiotic prescribing and referral for radiography, probably without compromising recovery. Trial registration The trial was registered in the ClinicalTrials.gov Protocol Registration System (identification number: NCT01794819). PMID:24886066

  20. Absorption of ethanol, acetone, benzene and 1,2-dichloroethane through human skin in vitro: a test of diffusion model predictions.

    PubMed

    Gajjar, Rachna M; Kasting, Gerald B

    2014-11-15

    The overall goal of this research was to further develop and improve an existing skin diffusion model by experimentally confirming the predicted absorption rates of topically-applied volatile organic compounds (VOCs) based on their physicochemical properties, the skin surface temperature, and the wind velocity. In vitro human skin permeation of two hydrophilic solvents (acetone and ethanol) and two lipophilic solvents (benzene and 1,2-dichloroethane) was studied in Franz cells placed in a fume hood. Four doses of each (14)C-radiolabed compound were tested - 5, 10, 20, and 40μLcm(-2), corresponding to specific doses ranging in mass from 5.0 to 63mgcm(-2). The maximum percentage of radiolabel absorbed into the receptor solutions for all test conditions was 0.3%. Although the absolute absorption of each solvent increased with dose, percentage absorption decreased. This decrease was consistent with the concept of a stratum corneum deposition region, which traps small amounts of solvent in the upper skin layers, decreasing the evaporation rate. The diffusion model satisfactorily described the cumulative absorption of ethanol; however, values for the other VOCs were underpredicted in a manner related to their ability to disrupt or solubilize skin lipids. In order to more closely describe the permeation data, significant increases in the stratum corneum/water partition coefficients, Ksc, and modest changes to the diffusion coefficients, Dsc, were required. The analysis provided strong evidence for both skin swelling and barrier disruption by VOCs, even by the minute amounts absorbed under these in vitro test conditions. PMID:25283951

  1. Skin Biomes.

    PubMed

    Fyhrquist, N; Salava, A; Auvinen, P; Lauerma, A

    2016-05-01

    The cutaneous microbiome has been investigated broadly in recent years and some traditional perspectives are beginning to change. A diverse microbiome exists on human skin and has a potential to influence pathogenic microbes and modulate the course of skin disorders, e.g. atopic dermatitis. In addition to the known dysfunctions in barrier function of the skin and immunologic disturbances, evidence is rising that frequent skin disorders, e.g. atopic dermatitis, might be connected to a dysbiosis of the microbial community and changes in the skin microbiome. As a future perspective, examining the skin microbiome could be seen as a potential new diagnostic and therapeutic target in inflammatory skin disorders. PMID:27056560

  2. Quantitative differences in host cell reactivation of ultraviolet-damaged virus in human skin fibroblasts and epidermal keratinocytes cultured from the same foreskin biopsy

    SciTech Connect

    Tyrrell, R.M.; Pidoux, M.

    1986-06-01

    Repair efficiency of cultured cells may be estimated by measuring the ability of a particular cell type to support virus damaged by an appropriate agent. In this study we have compared the inactivation of ultraviolet (254 nm)-damaged herpes simplex virus in human fibroblast and epidermal keratinocyte cell lines derived from the same foreskin biopsy and found the epithelial cells to be a factor of 3 times less efficient in supporting the damaged virus. The two different cell types show comparable ultraviolet inactivation of clone-forming ability, indicating that the difference is specific to viral host cell reactivation. This study required the development of a quantitative infectious centers assay for the measurement of viral titer in human epithelial cells, a system which may be of more general application in studies of potential human carcinogens.

  3. Evaluation of ear skin temperature as a cow-side test to predict postpartum calcium status in dairy cows.

    PubMed

    Venjakob, P L; Borchardt, S; Thiele, G; Heuwieser, W

    2016-08-01

    Subclinical hypocalcemia is considered a gateway disease that increases susceptibility to other metabolic and infectious diseases in transition dairy cows. In the absence of a cow-side test, however, it is difficult to identify hypocalcemic cows. The objective of this study was to evaluate ear skin temperature as a diagnostic predictor of serum calcium concentration. We conducted a cross-sectional study on 7 commercial dairy farms, involving 251 cows 0 to 48h after calving. Skin temperature of the ears (STEar) was scored manually by palpating both ears. An infrared thermometer was used to measure ear temperature, skin temperature on the coxal tuber (STCox), and ambient temperature. Rectal temperature was measured using a digital thermometer. A blood sample was drawn to determine serum calcium concentration. Hypocalcemia was defined as serum calcium below 2.0mmol/L, irrespective of clinical symptoms. Serum calcium concentration <2.0mmol/L in connection with clinical symptoms was defined as clinical milk fever; serum calcium concentration <2.0mmol/L without clinical symptoms was defined as subclinical hypocalcemia. Multivariate analysis using the GENLINMIXED procedure and receiver operating characteristic analysis were performed to evaluate whether serum calcium concentration could be predicted using ear temperature and other temperature estimates. The prevalence of hypocalcemia was 3.3, 27.3, 32.8, and 69.6% for cows in first, second, third, and fourth or greater lactation, respectively. None of the cows in first and second lactation had clinical milk fever. The prevalence of clinical milk fever was 6.0 and 20.3% for cows in their third and fourth or greater lactation, respectively. A decrease in ear temperature of 0.39°C [95% confidence interval (CI): 0.25-0.54] was associated with a decrease of 0.1mmol/L in serum calcium concentration. Ambient temperature, however, was a major confounder for ear temperature. With an increase in ambient temperature of 1°C, STEar

  4. QuantiFERON-TB Gold and Tuberculin Skin Test for the Diagnosis of Latent Tuberculosis Infection in Children

    PubMed Central

    Masoumi Asl, Hossein; Alborzi, Abdolvahab; Pourabbas, Bahman; Kalani, Mehdi

    2015-01-01

    Background: Appropriate diagnosis and treatment of latent tuberculosis infection (LTBI) play the most important role in the control of tuberculosis. This study aimed to determine the prevalence of LTBI among healthy tuberculosis unexposed children vaccinated with BCG using the tuberculin skin test (TST) and QuantiFERON TB Gold In-Tube (QFT-GIT) and comparing the agreement between the two tests. Methods: A cross-sectional study was carried out between October 2009 and March 2010 in 24 schools and 11 daycare centers. A total of 967 children were divided into 15 age groups, with a minimum of 64 children per group. Results: The prevalence rates of LTBI with TST were 3.8%, and 2.2% with QFT-GIT. One case was positive in TST and QFT-GIT, 20 cases were QFT-GIT positive, but TST negative and 36 cases were TST positive, but QFT-GIT negative, and finally, 910 cases were negative in both. There was poor agreement between TST and QFT-GIT (1.8%, 95%, CI: 0%-5.3%, k=0.007). The specificity of QFT-GIT in the BCG vaccinated, children aged 1-15 years old, was 97.8% (97.8%, 95% CI: 96.8%-98.8%). After three months, 2/17 (11.8%) of those initially QFT-GIT negative converted, and 10/15 (66%) of those initially QFT-GIT positive reverted. Conclusion: It seems that TST and QFT-GIT are not appropriate tests for the diagnosis of LTBI among healthy tuberculosis unexposed BCG vaccinated children. There was a low reproducibility rate of QFT-GIT. The cause of the the poor agreement requires further studies. PMID:26379347

  5. Cardiovascular and cortisol reactivity and habituation to a virtual reality version of the Trier Social Stress Test: a pilot study.

    PubMed

    Jönsson, Peter; Wallergård, Mattias; Osterberg, Kai; Hansen, Ase Marie; Johansson, Gerd; Karlson, Björn

    2010-10-01

    The Trier Social Stress Test (TSST) is a widely used protocol to induce stress in laboratory settings. Briefly, in the TSST, the test participant is asked to hold a speech and to do an arithmetic task in front of an audience. In the present pilot study, we examined endocrine and autonomic reactivity and habituation to repeated stress provocations using a virtual reality (VR) version of TSST. The VR system was a CAVE™ system with three rear projected walls (4 m×3 m), and one floor projection. The system also included a head tracking system and passive stereoscopy. The virtual audience consisted of one woman, and two men. Ten healthy men, mean age 28.3 years (24-38 years), were confronted with the test twice (1 week between sessions), during which salivary cortisol, heart rate (HR), high frequency heart rate variability (HF-HRV, parasympathetic activity), and T-wave amplitude (TWA, suggested to be related to sympathetic influence on myocardial performance) were assessed. Cortisol secretion showed a marked increase (88% vs. baseline) during the first stress provocation, but habituated in the second session. The magnitude of HR and TWA reactivity during stress provocation was approximately the same at both sessions, implying a stable increase in sympathetic activity. Heart rate showed a maximum increase of 40% at the first session, and 32% at the second. TWA showed a maximum decrease of 42% at the first session, and 39% at the second. The results resemble those obtained in prior studies using the real-life TSST. If these results can be replicated with larger samples, VR technology may be used as a simple and standardized tool for social stress induction in experimental settings. PMID:20451329

  6. Quantitative sensory testing and pain-evoked cytokine reactivity: comparison of patients with sickle cell disease to healthy matched controls.

    PubMed

    Campbell, Claudia M; Carroll, C Patrick; Kiley, Kasey; Han, Dingfen; Haywood, Carlton; Lanzkron, Sophie; Swedberg, Lauren; Edwards, Robert R; Page, Gayle G; Haythornthwaite, Jennifer A

    2016-04-01

    Sickle cell disease (SCD) is an inherited blood disorder associated with significant morbidity, which includes severe episodic pain, and, often, chronic pain. Compared to healthy individuals, patients with SCD report enhanced sensitivity to thermal detection and pain thresholds and have altered inflammatory profiles, yet no studies to date have examined biomarker reactivity after laboratory-induced pain. We sought to examine this relationship in patients with SCD compared to healthy control participants. We completed quantitative sensory testing in 83 patients with SCD and sequential blood sampling in 27 of them, whom we matched (sex, age, race, body mass index, and education) to 27 healthy controls. Surprisingly, few quantitative sensory testing differences emerged between groups. Heat pain tolerance, pressure pain threshold at the trapezius, thumb, and quadriceps, and thermal temporal summation at 45°C differed between groups in the expected direction, whereas conditioned pain modulation and pain ratings to hot water hand immersion were counterintuitive, possibly because of tailoring the water temperature to a perceptual level; patients with SCD received milder temperatures. In the matched subsample, group differences and group-by-time interactions were observed in biomarkers including tumor necrosis factor alpha, interleukin-1ß, interleukin-4, and neuropeptide Y. These findings highlight the utility of laboratory pain testing methods for understanding individual differences in inflammatory cytokines. Our findings suggest amplified pain-evoked proinflammatory cytokine reactivity among patients with SCD relative to carefully matched controls. Future research is warranted to evaluate the impact of enhanced pain-related cytokine response and whether it is predictive of clinical characteristics and the frequency/severity of pain crises in patients with SCD. PMID:26713424

  7. Cardiovascular reactivity after blockade of angiotensin AT1 receptors in the experimental model of tilting test in conscious rats

    PubMed Central

    Bedette, D; Santos, R A S; Fontes, M A P

    2008-01-01

    Background and purpose: Studies have shown that the angiotensin II AT1 receptor antagonist, losartan, accentuates the hypotensive response in the orthostatic stress test (tilt) performed in anaesthetized rats. The same effect was not reported with other AT1 antagonists. The aim of this study was to re-evaluate the effects of AT1 receptor blockade on the cardiovascular response to tilt in a model developed for conscious rats. Experimental approach: Rats (n=5–7 per group) were instrumented for infusion of drugs and recording of cardiovascular parameters and, after recovery, placed in a plastic tube positioned over the tilt board. The tilt test was conducted by raising the head side of the tilt board from horizontal position to 75° head up position for 15 min. Key results: Compared with control group (NaCl 0.9%, 1 ml kg−1), oral treatment with 1 mg kg−1 per day of losartan or telmisartan did not alter the blood pressure response during tilt. With the 10 mg kg−1 dose, both antagonists altered the blood pressure response during tilt (mean maximum changes −11±3 mm Hg; P<0.01). A post-tilt hypotension was observed with both doses in losartan and telmisartan groups (−13±1 and −9±2 mm Hg, respectively; P<0.01). Conclusions and implications: The present results indicate that the effect of losartan on the cardiovascular reactivity to tilt shares a similar profile to that of other AT1 antagonists. Evidence discussed addresses the importance of using a conscious model for testing the influence of antihypertensive drugs on the cardiovascular reactivity to orthostatic challenges. PMID:18193073

  8. Reliable measures of behaviorally-evoked cardiovascular reactivity from a PC-based test battery: results from student and community samples.

    PubMed

    Kamarck, T W; Jennings, J R; Debski, T T; Glickman-Weiss, E; Johnson, P S; Eddy, M J; Manuck, S B

    1992-01-01

    This paper describes efforts to reduce measurement error in the assessment of cardiovascular reactivity by standardizing task requirements and by aggregating data across tasks and testing sessions. Using these methods, reliable measures of reactivity (.80 or greater) were obtained on five different measures of cardiovascular function (heart rate, systolic blood pressure, diastolic blood pressure, stroke volume, pre-ejection period) in samples of college students and community volunteers. Methodological limitations may have hampered previous efforts in this area. Current findings are consistent with a dispositional model of cardiovascular reactivity, and they suggest productive future strategies for obtaining reliable assessments. PMID:1609024

  9. Cystic Fibrosis Transmembrane Conductance Regulator: Using Differential Reactivity toward Channel-Permeant and Channel-Impermeant Thiol-Reactive Probes To Test a Molecular Model for the Pore†

    PubMed Central

    2009-01-01

    The sixth transmembrane segment (TM6) of the CFTR chloride channel has been intensively investigated. The effects of amino acid substitutions and chemical modification of engineered cysteines (cysteine scanning) on channel properties strongly suggest that TM6 is a key component of the anion-conducting pore, but previous cysteine-scanning studies of TM6 have produced conflicting results. Our aim was to resolve these conflicts by combining a screening strategy based on multiple, thiol-directed probes with molecular modeling of the pore. CFTR constructs were screened for reactivity toward both channel-permeant and channel-impermeant thiol-directed reagents, and patterns of reactivity in TM6 were mapped onto two new, molecular models of the CFTR pore: one based on homology modeling using Sav1866 as the template and a second derived from the first by molecular dynamics simulation. Comparison of the pattern of cysteine reactivity with model predictions suggests that nonreactive sites are those where the TM6 side chains are occluded by other TMs. Reactive sites, in contrast, are generally situated such that the respective amino acid side chains either project into the predicted pore or lie within a predicted extracellular loop. Sites where engineered cysteines react with both channel-permeant and channel-impermeant probes occupy the outermost extent of TM6 or the predicted TM5−6 loop. Sites where cysteine reactivity is limited to channel-permeant probes occupy more cytoplasmic locations. The results provide an initial validation of two, new molecular models for CFTR and suggest that molecular dynamics simulation will be a useful tool for unraveling the structural basis of anion conduction by CFTR. PMID:19754156

  10. Contribution of phenols, quinones and reactive oxygen species to the mutagenicity of white grape juice in the Ames test.

    PubMed

    Patrineli, A; Clifford, M N; Ioannides, C

    1996-09-01

    The purpose of this study was to evaluate the role of phenols, quinones and reactive oxygen species in the mutagenicity of white grape juice in the Ames mutagenicity test. Mutagenicity was markedly suppressed by reduced glutathione but was not influenced by superoxide dismutase or catalase. In the presence of grape polyphenol oxidase, the mutagenicity of grape juice was markedly increased. When hepatic cytosol from Aroclor 1254-induced rats, supplemented with a reduced nicotinamide adenine dinucleotide phosphate-generating system. served as an activation system, an increase in the mutagenicity of grape juice was observed. The cytosol-induced mutagenicity of grape juice was attenuated in the presence of superoxide dismutase, catalase and glutathione. It is concluded that polyphenol oxidase-catalysed oxidation of phenolic compounds generates genotoxic species that are, at least partly, responsible for the mutagenicity of grape juice. In the presence of hepatic cytosol, one-electron reduction of grape juice quinones leads to the production of reactive oxygen species resulting in an increase in the mutagenic response. PMID:8972879

  11. Modeling and testing of reactive contaminant transport in drinking water pipes: Chlorine response and implications for online contaminant detection

    EPA Science Inventory

    Reactive contaminants introduced to chlorinated drinking water can cause water quality change directly related to their reactivity and other physiochemical properties. This general principle is further developed and utilized in a proposed real-time event adaptive detection, iden...

  12. Biochemical and physiological parameters on the skin surface of healthy test persons: a contribution towards the interpretation of the results obtained by a screening program.

    PubMed

    Gloor, M; Kionke, M; Friederich, H C

    1975-07-18

    Biochemical and physiological examinations were carried out on the skin surface of a total of 115 healthy persons ranging from the age of 7-79 years. In these investigations the following striking findings were made: 1. There is a significant correlation between the results obtained by the ferricyanide, the phenol sulfuric acid and the ninhydrin methods in the so called water solubles. 2. The relationship between the fraction of wax and cholesterol esters and the squalene fraction in the skin surface lipids influences the release of free fatty acids by bacterial lipases. 3. With regards to most parameters tested there are great differences between the 8-12 year age group and the older age groups. 4. There are significant differences in the 8-12 year age group between the male and female test persons. 5. With regards to the parameters tested there are also significant differences between the various test areas. PMID:1164042

  13. The complex problem of sensitive skin.

    PubMed

    Marriott, Marie; Holmes, Jo; Peters, Lisa; Cooper, Karen; Rowson, Matthew; Basketter, David A

    2005-08-01

    There exists within the population subsets of individuals who display heightened skin reactivity to materials the majority find tolerable. In a series of investigations, we have examined interrelationships between many of the endpoints associated with the term 'sensitive skin'. In the most recent work, 58 volunteers were treated with 10% lactic acid, 50% ethanol, 0.5% menthol and 1.0% capsaicin on the nasolabial fold, unoccluded, with sensory reactions recorded at 2.5 min, 5 min and 8 min after application. Urticant susceptibility was evaluated with 1 m benzoic acid and 125 mM trans-cinnamic acid applied to the volar forearm for 20 min. A 2 x 23-h patch test was also conducted using 0.1% and 0.3% sodium dodecyl sulfate, 0.3% and 0.6% cocamidopropyl betaine and 0.1% and 0.2% benzalkonium chloride to determine irritant susceptibility. As found in previous studies, increased susceptibility to one endpoint was not predictive of sensitivity to another. In our experience, nasolabial stinging was a poor predictor of general skin sensitivity. Nevertheless, it may be possible to identify in the normal population individuals who, coincidentally, are more generally sensitive to a range of non-immunologic adverse skin reactions. Whether such individuals are those who experience problems with skin care products remains to be addressed. PMID:16033403

  14. Re-evaluation of the 1962 Mark VI-B dynamic tests regarding reactivity coefficients

    SciTech Connect

    Burnett, T.

    1991-06-01

    The 1962 Mark VI-B rod tests have been re-evaluated. A significantly lower (more negative) coolant coefficient is now ascribed to that test, {minus}1 pcm/Deg-C vs the previously reported +2 pcm/Deg-C. The change from the previous value is because of revisions to delayed neutron constants and accounting for spatial effects. The new value is in reasonable agreement with the currently calculated value of {minus}2 pcm/Deg-C, considering measurement and calculational uncertainties. Therefore, the authors conclude that the current analytic models for physics and transient analysis methodology (GLASS, GRIMHX & TRIMHX, AND MARY) are fully consistent with 1962 test observations, and that there is no basis for assigning a calculational bias or increasing uncertainty allowances.

  15. Tuberculin Skin-Test Reactions Are Unaffected by the Severity of Hyperendemic Intestinal Helminth Infections and Co-Infections

    PubMed Central

    Zevallos, Karine; Vergara, Katherine C.; Vergara, Antonio; Vidal, Carlos; Garcia, Hector H.; Evans, Carlton A.

    2010-01-01

    The tuberculin skin test (TST) quantifies cell-mediated immunity to tuberculosis antigens. Helminths suppress cell-mediated immunity, so we studied the effect of helminth infection and deworming on the TST in a randomized, double-blind, placebo-controlled study in an indigenous Amazon community (N = 195). Stool microscopy diagnosed helminths in 98% and co-infection with multiple species in 24% of study subjects. The TST was positive (≥ 10 mm) for 49%, and responses increased with age (P < 0.001), Bacille Calmette Guerin (BCG) vaccination (P = 0.01), and tuberculosis contact (P = 0.05). TST results had no association with helminth-egg concentrations, species, or co-infections (all P > 0.1). One month after deworming with albendazole (three daily 400-mg doses), helminths were reduced, but 63% remained infected with helminths. Albendazole did not cause a change in TST size (P = 0.8) or positivity (P = 0.9) relative to placebo. Thus, TST reactions were unaffected by albendazole therapy that partially cured intestinal helminth infections, and TST interpretation was unaffected by high-burden helminth infections and co-infection with multiple helminth species. PMID:20682875

  16. IgE Sensitization Patterns to Commonly Consumed Foods Determined by Skin Prick Test in Korean Adults.

    PubMed

    Kim, Sung Ryeol; Park, Hye Jung; Park, Kyung Hee; Lee, Jae-Hyun; Park, Jung-Won

    2016-08-01

    Offending food allergens can vary with regional preferences in food consumption. In this study, we analysed sensitization rates to commonly consumed foods in Korean adults suspected of having food allergy. One hundred and thirty four subjects underwent a skin prick test (SPT) with 55 food allergens, of which 13 were made by our laboratory and the rest were commercially purchased. Of the 134 patients, 73 (54.5%) were sensitized to one or more food allergens. Sensitization to chrysalis was detected most frequently, at a rate of 25.4%. Sensitization rates to other food allergens were as follows: maize grain (13.4%), shrimp (11.9%), almond (11.1%), wheat flour (8.2%), lobster (8.2%), buckwheat (8.2%), mackerel (5.2%), pollack (5.2%), halibut (4.5%), peanut (4.5%), anchovy (4.4%), squid (3.7%), saury (3.0%), common eel (3.0%), yellow corvina (3.0%), hairtail (2.2%), octopus (2.2%), and others. In addition to well-known food allergens, sensitivity to mackerel, chrysalis, pollack, and halibut, which are popular foods in Korea, was observed at high rates in Korean adults. We suggest that the SPT panel for food allergy in Korea should include these allergens. PMID:27478328

  17. Memory detection with the Concealed Information Test: a meta analysis of skin conductance, respiration, heart rate, and P300 data.

    PubMed

    Meijer, Ewout H; Selle, Nathalie Klein; Elber, Lotem; Ben-Shakhar, Gershon

    2014-09-01

    The Concealed Information Test (CIT) uses psychophysiological measures to determine the presence or absence of crime-related information in a suspect's memory. We conducted a meta-analysis on the validity of the CIT based on four physiological measures-skin conductance response (SCR), respiration line length (RLL), changes in heart rate (HR), and enhanced amplitudes of the P300 component of the event-related potential (P300). This meta-analysis relied on laboratory studies that used either the mock-crime or the personal-item paradigm. Results showed a mean effect size (d*) of 1.55 for SCR, 1.11 for RLL, 0.89 for HR, and 1.89 for P300. However, P300 outperformed SCR only in the personal-item paradigm, but not in the mock-crime paradigm. Motivation level, number of questions, publication year, and the inclusion of innocent participants emerged as significant moderators for the SCR, while only the type of paradigm used moderated the P300 effect. PMID:24916920

  18. IgE Sensitization Patterns to Commonly Consumed Foods Determined by Skin Prick Test in Korean Adults

    PubMed Central

    2016-01-01

    Offending food allergens can vary with regional preferences in food consumption. In this study, we analysed sensitization rates to commonly consumed foods in Korean adults suspected of having food allergy. One hundred and thirty four subjects underwent a skin prick test (SPT) with 55 food allergens, of which 13 were made by our laboratory and the rest were commercially purchased. Of the 134 patients, 73 (54.5%) were sensitized to one or more food allergens. Sensitization to chrysalis was detected most frequently, at a rate of 25.4%. Sensitization rates to other food allergens were as follows: maize grain (13.4%), shrimp (11.9%), almond (11.1%), wheat flour (8.2%), lobster (8.2%), buckwheat (8.2%), mackerel (5.2%), pollack (5.2%), halibut (4.5%), peanut (4.5%), anchovy (4.4%), squid (3.7%), saury (3.0%), common eel (3.0%), yellow corvina (3.0%), hairtail (2.2%), octopus (2.2%), and others. In addition to well-known food allergens, sensitivity to mackerel, chrysalis, pollack, and halibut, which are popular foods in Korea, was observed at high rates in Korean adults. We suggest that the SPT panel for food allergy in Korea should include these allergens. PMID:27478328

  19. Mechanism of photobiological effects of psoralens: the involvement of photo-oxidized psoralens as reactive intermediate species in induction of photosensitized hemolysis and skin erythema

    NASA Astrophysics Data System (ADS)

    Lysenko, Eugene P.; Kyagova, Alla A.; Potapenko, Alexander Y.

    2002-07-01

    Psoralens combined with UVA irradiation are used for the treatment of skin and autoimmune diseases. In the present paper the involvement of psoralen photooxidation products (POP) into induction of PUVA-erythema was studied. Under low fluence rate (LFR) UVA-irradiation and/or at low psoralen concentrations POP-products were predominantly formed, which were detected by spin trp method and possessed immunosuppressive activity. Under high fluence rate (HFR) UVA-irradiation and/or at high psoralen concentrations POP2-products were predominantly formed, which could be detected by Fe(II)-induced chemiluminescence and possessed hemolytic activity. Both PUVA- and POP-induced hemolysis of erythrocytes as well as PUVA-erythema were strongly activated with the increase in UVA-fluence rate. Both LFR and HFR PUVA-hemolysis as well as POP-hemolysis were strongly activated by Fe(II)-ions, bivalent cation chelators produced different effects on these processes depending on UVA fluence rate. Ethylenediaminetetraacetate (EDTA), and o- fenanthroline were found to inhibit LFT PUVA-erythema and enhanced HFR PUVA-erythema. Similar regulatory effects of EDTA were found for PUVA- and POP-induced hemolysis. EDTA inhibited LFT PUVA-hemolysis and activated HFR PUVA- and POP-hemolysis that suggests a participation of POP1- products in induction of LFR PUVA-hemolysis and LFT PUVA- erythema and POP2-products in induction of HFR PUVA- hemolysis and HFR PUVA-erythema.

  20. Evaluation by the Double Loop Electrochemical Potentiokinetic Reactivation Test of Aged Ferritic Stainless Steel Intergranular Corrosion Susceptibility

    NASA Astrophysics Data System (ADS)

    Sidhom, H.; Amadou, T.; Braham, C.

    2010-12-01

    An experimental design method was used to determine the effect of factors that significantly affect the response of the double loop-electrochemical potentiokinetic reactivation (DL-EPR) test in controlling the susceptibility to intergranular corrosion (IGC) of UNS S43000 (AISI 430) ferritic stainless steel. The test response is expressed in terms of the reactivation/activation current ratio ( I r / I a pct). Test results analysed by the analysis of variance (ANOVA) method show that the molarity of the H2SO4 electrolyte and the potential scanning rate have a more significant effect on the DL-EPR test response than the temperature and the depassivator agent concentration. On the basis of these results, a study was conducted in order to determine the optimal operating conditions of the test as a nondestructive technique for evaluating IGC resistance of ferritic stainless steel components. Three different heat treatments are considered in this study: solution annealing (nonsensitized), aging during 3 hours at 773 K (500 °C) (slightly sensitized), and aging during 2 hours at 873 K (600 °C) (highly sensitized). The aim is to find the operating conditions that simultaneously ensure the selectivity of the attack (intergranular and chromium depleted zone) and are able to detect the effect of low dechromization. It is found that a potential scanning rate of 2.5 mV/s in an electrolyte composed of H2SO4 3 M solution without depassivator, at a temperature around 293 K (20 °C), is the optimal operating condition for the DL-EPR test. Using this condition, it is possible to assess the degree of sensitization (DOS) to the IGC of products manufactured in ferritic stainless steels rapidly, reliably, and quantitatively. A time-temperature-start of sensitization (TTS) diagram for the UNS S43000 (France Inox, Villepinte, France) stainless steel was obtained with acceptable accuracy by this method when the IGC sensitization criterion was set to I r / I a > 1 pct. This diagram is in

  1. FURNACE SORBENT REACTIVITY TESTING FOR CONTROL OF SO2 EMISSIONS FROM ILLINOIS COALS

    EPA Science Inventory

    Research was undertaken to evaluate the potential of furnai sorbent injection (FSI) for sulf dioxide (S02) emission controlcoal-fired boilers utilizing coals indigenous to Illinois. Tests were run using four coals from the Illinois Basin and six calcium hydroxide [Ca(OH)2], sorbe...

  2. Experimenter Effects on Cardiovascular Reactivity and Task Performance during Mental Stress Testing

    ERIC Educational Resources Information Center

    Siegwarth, Nicole; Larkin, Kevin T.; Kemmner, Christine

    2012-01-01

    Experimenter effects have long been hypothesized to influence participants' responses to mental stress testing. To explore the influence of experimenter warmth on responses to two mental stress tasks (mental arithmetic, mirror tracing), 32 young women participated in a single 45-min experimental session. Participants were randomized into warm…

  3. FURNACE SURBENT REACTIVITY TESTING FOR CONTROL OF SO2 EMISSIONS FROM ILLINOIS COALS

    EPA Science Inventory

    Research was undertaken to evaluate the potential of furnai sorbent injection (FSI) for sulf dioxide (S02) emission controlcoal-fired boilers utilizing coals indigenous to Illinois. Tests were run using four coals from the Illinois Basin and six calcium hydroxide [Ca(OH)2], sorbe...

  4. Lessons Learned from the Construction of Upgrades to the NASA Glenn Icing Research Tunnel and Re-activation Testing

    NASA Technical Reports Server (NTRS)

    Sheldon, David W.; Andracchio, Charles R.; Krivanek, Thomas M.; Spera, David A.; Austinson, Todd A.

    2001-01-01

    Major upgrades were made in 1999 to the 6- by 9-Foot (1.8- by 2.7-m) Icing Research Tunnel (IRT) at the NASA Glenn Research Center. These included replacement of the electronic controls for the variable-speed drive motor, replacement of the heat exchanger, complete replacement and enlargement of the leg of the tunnel containing the new heat-exchanger, the addition of flow-expanding and flow-contracting turning vanes upstream and downstream of the heat exchanger, respectively, and the addition of fan outlet guide vanes (OGV's). This paper presents an overview of the construction and reactivation testing phases of the project. Important lessons learned during the technical and contract management work are documented.

  5. Tuberculin skin test and ELISPOT/T. SPOT.TB in children and adolescents with juvenile idiopathic arthritis

    PubMed Central

    2014-01-01

    Background There are controversies regarding the accuracy of the tuberculin skin test (TST) and methods based on the production of interferon gamma by sensitized T cells for the diagnosis of latent tuberculosis infection (LTBI) in pediatrics and immunosuppressed patients. Our objectives are to study TST and ELISPOT/T. SPOT.TB in the diagnosis of LTBI in children and adolescents with JIA undergoing methotrexate, the correlation between both and the sensitivity and specificity of T. SPOT.TB. Methods This is an observational prospective longitudinal study in which children and adolescents with JIA undergoing methotrexate therapy were assessed for clinical and epidemiological data for LTBI, in addition to performing TST and T. SPOT.TB at baseline and after 3 and 12months. Results There were 24 patients. The prevalence of LTBI at inclusion was 20.8%, the incidence after initiation of immunosuppressions 26.3% and the prevalence at the end of the study 41.6%. Epidemiological history positive for TB showed a relative risk of 2.0 for the development of LTBI. Only 2 patients had positive T. SPOT.TB but only in one it was useful for detecting early LTBI. T. SPOT.TB presented a sensitivity of 10%, specificity of 92.8%, and low correlation with TST. No patient developed TB disease at a mean follow-up of 47months. Conclusions We found a high prevalence of ILTB that doubled with immunosuppression and that epidemiological history was an important relative risk. T. SPOT.TB showed low sensitivity and high specificity, and no superiority over TST. There was low agreement and little influence of immunosuppression on the results of both tests. PMID:24904240

  6. Reactivity measurement in estimation of benzoquinone and benzoquinone derivatives' allergenicity.

    PubMed

    Mbiya, Wilbes; Chipinda, Itai; Simoyi, Reuben H; Siegel, Paul D

    2016-01-01

    Benzoquinone (BQ) and benzoquinone derivatives (BQD) are used in the production of dyes and cosmetics. While BQ, an extreme skin sensitizer, is an electrophile known to covalently modify proteins via Michael Addition (MA) reaction whilst halogen substituted BQD undergo nucleophilic vinylic substitution (SNV) mechanism onto amine and thiol moieties on proteins, the allergenic effects of adding substituents on BQ have not been reported. The effects of inserting substituents on the BQ ring has not been studied in animal assays. However, mandated reduction/elimination of animals used in cosmetics testing in Europe has led to an increased need for alternatives for the prediction of skin sensitization potential. Electron withdrawing and electron donating substituents on BQ were assessed for effects on BQ reactivity toward nitrobenzene thiol (NBT). The NBT binding studies demonstrated that addition of EWG to BQ as exemplified by the chlorine substituted BQDs increased reactivity while addition of EDG as in the methyl substituted BQDs reduced reactivity. BQ and BQD skin allerginicity was evaluated in the murine local lymph node assay (LLNA). BQD with electron withdrawing groups had the highest chemical potency followed by unsubstituted BQ and the least potent were the BQD with electron donating groups. The BQD results demonstrate the impact of inductive effects on both BQ reactivity and allergenicity, and suggest the potential utility of chemical reactivity data for electrophilic allergen identification and potency ranking. PMID:26612505

  7. Isoflavonoid-Rich Flemingia macrophylla Extract Attenuates UVB-Induced Skin Damage by Scavenging Reactive Oxygen Species and Inhibiting MAP Kinase and MMP Expression

    PubMed Central

    Chiang, Hsiu-Mei; Chiu, Hua-Hsien; Liao, Sue-Tsai; Chen, Yen-Ting; Chang, Hsien-Chang; Wen, Kuo-Ching

    2013-01-01

    In this study, we investigated the antioxidant activity and anti-photoaging properties of an extract of Flemingia macrophylla, a plant rich in isoflavonoid content. Pretreatment of fibroblasts with Flemingia macrophylla extract (FME) inhibited elastase activity, promoted the protein expression of type I procollagen, and attenuated the phosphorylation of mitogen-activated protein (MAP) kinase and the protein expression of matrix-metalloproteinase- (MMP-) 1, 3, and 9. The IC50 values were 2.1 μg/mL for DPPH radical scavenging ability, 366.8 μg/mL for superoxide anion scavenging ability, 178.9 μg/mL for hydrogen peroxide scavenging ability, and 230.9 μg/mL for hydroxyl radical scavenging ability. Also, exposure of erythrocytes to various concentrations of FME (50–500 μg/mL) resulted in a dose- and time-dependent inhibition of AAPH-induced hemolysis. In human fibroblasts, FME at 10 μg/mL was shown to be a potent scavenger of UV-induced reactive oxygen species (ROS). The antioxidant and anti-photoaging properties of FME make it an ideal anti-intrinsic aging and anti-photoaging agent. PMID:23935672

  8. Isoflavonoid-Rich Flemingia macrophylla Extract Attenuates UVB-Induced Skin Damage by Scavenging Reactive Oxygen Species and Inhibiting MAP Kinase and MMP Expression.

    PubMed

    Chiang, Hsiu-Mei; Chiu, Hua-Hsien; Liao, Sue-Tsai; Chen, Yen-Ting; Chang, Hsien-Chang; Wen, Kuo-Ching

    2013-01-01

    In this study, we investigated the antioxidant activity and anti-photoaging properties of an extract of Flemingia macrophylla, a plant rich in isoflavonoid content. Pretreatment of fibroblasts with Flemingia macrophylla extract (FME) inhibited elastase activity, promoted the protein expression of type I procollagen, and attenuated the phosphorylation of mitogen-activated protein (MAP) kinase and the protein expression of matrix-metalloproteinase- (MMP-) 1, 3, and 9. The IC50 values were 2.1  μ g/mL for DPPH radical scavenging ability, 366.8  μ g/mL for superoxide anion scavenging ability, 178.9  μ g/mL for hydrogen peroxide scavenging ability, and 230.9  μ g/mL for hydroxyl radical scavenging ability. Also, exposure of erythrocytes to various concentrations of FME (50-500  μ g/mL) resulted in a dose- and time-dependent inhibition of AAPH-induced hemolysis. In human fibroblasts, FME at 10  μ g/mL was shown to be a potent scavenger of UV-induced reactive oxygen species (ROS). The antioxidant and anti-photoaging properties of FME make it an ideal anti-intrinsic aging and anti-photoaging agent. PMID:23935672

  9. Malondialdehyde measurement in oxidized foods: evaluation of the spectrophotometric thiobarbituric acid reactive substances (TBARS) test in various foods.

    PubMed

    Papastergiadis, Antonios; Mubiru, Edward; Van Langenhove, Herman; De Meulenaer, Bruno

    2012-09-26

    The ability of the spectrophotometric thiobarbituric acid reactive substances (TBARS) test to determine malondialdehyde (MDA) in various food matrices was evaluated. MDA was extracted from the foods; the extract reacted with thiobarbituric acid (TBA); and the formed TBA-MDA adduct was measured spectrophotometricaly at 532 nm. In parallel, the TBA-MDA adduct was analyzed with high-performance liquid chromatography (HPLC) coupled with fluorescence detection. Oils and unprocessed and uncooked meat and fish products did not exhibit any significant difference in the amount of MDA measured by the two methods, indicating that the major substance reacting with TBA and forming an adduct that absorbs at 532 nm was MDA. However, in products such as dry nuts, pork sausages, cooked fish, and gouda cheese, an overestimation of MDA was observed, indicating that TBARS test was unsuitable for accurate determination of MDA. Furthermore, the results in the present work suggest that the overestimation of MDA by the TBARS test as it was applied is related to the interference of other than secondary lipid oxidation products. PMID:22950760

  10. Agreement of skin test with IL-4 production and CD40L expression by T cells upon immunotherapy of subjects with systemic reactions to Hymenoptera stings.

    PubMed

    Urra, José M; Cabrera, Carmen M; Alfaya, Teresa; Feo-Brito, Francisco

    2016-02-01

    Venom immunotherapy is the only curative intervention for subjects with Hymenoptera venom allergy who suffering systemic reactions upon bee or wasp stings. Venom immunotherapy can restore normal immunity against venom allergens, as well as providing to allergic subjects a lifetime tolerance against venoms. Nevertheless, it is necessary using safety assays to monitoring the development of tolerance in the VIT protocols to avoid fatal anaphylactic reactions. The purpose of this study was to assess the modifications in several markers of tolerance induction in subjects with Hymenoptera venom allergy undergoing immunotherapy. The studies were performed at baseline time and after six month of VIT. Intradermal skin tests, basophil activation tests, specific IgE levels; and the T-cell markers (IL-4 and IFN-γ producing cells; and expression of the surface activation markers CD40L and CTLA-4) were assayed. At six month of immunotherapy all parameters studied had significant alterations. All decreased, except the IFN-γ producing cells. In addition, modifications in intradermal skin test showed a significant correlation with both, CD40L expression on CD4 T lymphocytes (p=0.043) and IL-4 producing T lymphocytes (p=0.012). Neither basophil activation test nor serum levels of sIgE demonstrated any correlation with the immunological parameters studied nor among them. These results suggest that both IL-4 production and CD40L expression could be two good indicators of the beneficial effects of venom immunotherapy which translate into skin tests. PMID:26774053

  11. Comprehensive isolation of natural organic matter from water for spectral characterizations and reactivity testing

    USGS Publications Warehouse

    Leenheer, J.A.; Croue, J.-P.; Benjamin, M.; Korshin, G.V.; Hwang, C.J.; Bruchet, A.; Aiken, G.R.

    2000-01-01

    A variety of approaches were tested to comprehensively isolate natural organic matter (NOM) from water. For waters with high NOM concentrations such as the Suwannee River, Georgia, approaches that used combinations of membrane concentrations, evaporative concentrations, and adsorption on nonionic XAD resins, ion exchange resins and iron oxide coated sand isolated over 90% of the NOM. However, for waters with low NOM concentrations, losses of half of the NOM were common and desalting of NOM isolates was a problem. A new comprehensive approach was devised and tested on the Seine River, France in which 100 L of filtered water was sodium softened by ion exchange and vacuum evaporated to 100 mL. Colloids (32% of the NOM) were isolated using a 3,500 Dalton membrane by dialysis against 0.1 M HCl and 0.2 M HF to remove salts and silica. On the membrane permeate, hydrophobic NOM (42%) was isolated using XAD-8 resin and hydrophilic NOM (26%) was isolated using a variety of selective desalting precipitations. The colloid fraction was characterized by IR and NMR spectroscopy as N-acetylamino sugars. ?? 2000 American Chemical Society.

  12. Is Reactive Dengue NS1Antigen Test a Warning Call for Hospital Admissions?

    PubMed Central

    Kamalakannan, Banupriya; Thulasingam, Mahalakshmy; Sampath, Srinivasan

    2016-01-01

    Introduction Dengue fever is a major public health problem worldwide. The 2011 revised World Health Organization (WHO) guidelines have emphasized on early diagnosis and intervention to reduce the case fatality rate due to dengue fever. Rapid diagnostic tests like NS1 antigen assays have improved the detection of cases in early clinical phase of illness but its role as a predictor of severe dengue infection is not very clear. Aim To evaluate the utility of NS1 Ag assay as an early diagnostic marker and predictor of severe dengue infection. Materials and Methods All children (0-12 years of age) diagnosed and confirmed with dengue fever at a tertiary care hospital in Puducherry between 01st August 2012 and 31st July 2015 were reviewed retrospectively from hospital case records as per the revised WHO guidelines for dengue fever. The diagnosis was confirmed by NS1antigen-based ELISA test or dengue serology for IgM and IgG antibodies and the data were analysed using SPSS 16.0 statistical software. After collecting all the data, all the variables were summarised by descriptive statistics. Categorical variables were expressed as frequencies and percentages, and then analysed by the χ2 test or fishers exact test, where appropriate. Significance was taken at p-value< 0.05. Results Among the 261 confirmed cases of dengue fever non-severe dengue and severe dengue infection was seen in 60.9% and 39.1% respectively. The mean age of presentation was 6.9 years and M:F ratio was 1.2:1. NS1 Ag was positive in 217 cases (83.1%) and among them non-severe dengue and severe dengue was seen in 65.9% and 34.1% cases respectively. A total of 44 cases (16.9%) were negative for NS1 Ag assay and positive for IgM MAC ELISA and among them 16 children (36.4%) had non-severe dengue infection where as 28 children (63.6%) had severe dengue infection. Secondary infection with (MAC-ELISA IgG) was seen in 17 cases (6.5%). NS1Ag assay was predominantly positive in acute phase sera, where as Ig

  13. The Evaluation of the Impact of Age, Skin Tags, Metabolic Syndrome, Body Mass Index, and Smoking on Homocysteine, Endothelin-1, High-sensitive C-reactive Protein, and on the Heart

    PubMed Central

    El Safoury, Omar Soliman; Ezzat, Marwa; Abdelhamid, Mahmoud F; Shoukry, Nadia; Badawy, Ehssan

    2013-01-01

    Background: Skin tags (STs) are small, pedunculated skin-colored or brown papules that occur around any site where skin folds occur. The literature is short of comprehensive and controlled clinical studies aimed to evaluate the atherogenic risk factors in patients with STs. Aim of Work: The aim of this study is to evaluate the impact of age, STs, metabolic syndrome (METs), body mass index (BMI), and smoking on homocysteine (Hcy), endothelin-1 (ET-1), high-sensitive C-reactive protein (Hs-CRP), and on cardiovascular diseases. Materials and Methods: This study included 30 cardiac patients with STs, 30 non-cardiac patients with STs, and 30 healthy controls with neither heart disease nor STs. History of smoking, measurement of height, weight, BMI, waist circumference (WC), blood pressure, STs number, color, acanthosis nigricans, estimation of serum level of fasting glucose, triglycerides (TGs), cholesterol, high-dense lipoproteins (HDL), Hcy, ET-1, Hs-CRP, and the presence of the METs were elicited in the three groups. Results: Regarding the Hcy, ET-1, and Hs-CRP, the cardiac-STs group showed the highest levels and the control group showed the least (P < 0.001). The percents of patients with METs were 56.7% in the cardiac-STs, 40% in the non-cardiac-STs, and 0% in the control group (P < 0.001). Mean BMI exceeded the limit of obesity in the cardiac-STs group (30.9 ± 3.9) and the non-cardiac-STs group (32.6 ± 6) and was normal in the control group (24.7 ± 2.8). Hyperpigmented STs were present in 66.7% of the cardiac-STs group. Multivariate regression analysis for the independent effectors on Hcy level were the presence of STs (P < 0.001), METs (P = 0.001), and BMI (P = 0.024). Regarding ET-1, the effectors were the presence of STs and METs (P = 0.032). For Hs-CRP, effectors were the presence of STs (P < 0.001) and smoking (P = 0.040). Multivariate logistic regression of the predictors of cardiac disease showed that the independent predictors of the occurrence of

  14. Relationship of phospholipid chemistry to serological reactivity in the Venereal Disease Research Laboratory slide test antigen.

    PubMed Central

    Reeves, M W; McGrew, B E; McLaurin, B; Pine, L

    1981-01-01

    A total of 13 egg lecithins, 12 beef heart lecithins, and 15 beef heart cardiolipins were assayed for the ability to function in the Venereal Disease Research Laboratory microflocculation test, as well as for purity, fatty acid composition, free amines, metals, and products of oxidation. We found that the presence of peroxides and oxidation-related ultraviolet-absorbing chromophores showed a close inverse relationship to acceptable serological activity. The degree of purity of the lipids had only a slight influence on serological activity, whereas fatty acid composition, saturation, and configuration had none at all. We did not detect contaminating iron, copper, cobalt, nickel, or free amines in these lipids. We discuss the implications of our findings for improving the chemical standards for these lipids. Images PMID:7263853

  15. Evaluation of the usefulness of Treponema pallidum hemagglutination test in the diagnosis of syphilis in weak reactive Venereal Disease Research Laboratory sera

    PubMed Central

    Bala, Manju; Toor, Aman; Malhotra, Meenakshi; Kakran, Monika; Muralidhar, Sumathi; Ramesh, V.

    2012-01-01

    Background and Objectives: Biological false positive (BFP) reactivity by the Venereal Disease Research Laboratory (VDRL) test used for diagnosis of syphilis is a cause for concern. The use of the VDRL as a screening procedure is challenged by some studies. The aim of this study is to determine the prevalence of BFP reactions in different subject groups and to assess the usefulness of Treponema pallidum hemagglutination (TPHA) test in low titre VDRL reactive sera. Materials and Methods: A total of 5785 sera from sexually transmitted diseases (STD) clinic attendees, antenatal clinic attendees, husbands of antenatal cases, peripheral health centres attendees (representing community population) and from patients referred from different OPDs/wards were screened for BFP reactions by the VDRL test. Sera reactive in the VDRL test were confirmed by the TPHA test. Results: Out of 80 qualitative VDRL reactive sera, 68 had <1:8 titre on quantitation and TPHA was positive in 59 samples, indicating BFP reactivity in 0.2% in all the subject groups. BFP was nil in the community population. The male-to-female ratio of BFP reactions was 2:1. VDRL and TPHA positivity was highest (76%) in the age group of 20-29 years. The seroprevalence of syphilis varied from 0.4% to 3.5% in different patient groups. Conclusions: The results of this study highlight that the TPHA positivity was high (86.8%) in sera with VDRL titre less than 1:8. Therefore, for the diagnosis of syphilis, it is recommended that a confirmatory test such as TPHA should be performed on all sera with a reactive VDRL regardless of its titre. PMID:23188934

  16. Xenobiotic metabolism capacities of human skin in comparison with a 3D-epidermis model and keratinocyte-based cell culture as in vitro alternatives for chemical testing: phase II enzymes.

    PubMed

    Götz, Christine; Pfeiffer, Roland; Tigges, Julia; Ruwiedel, Karsten; Hübenthal, Ulrike; Merk, Hans F; Krutmann, Jean; Edwards, Robert J; Abel, Josef; Pease, Camilla; Goebel, Carsten; Hewitt, Nicola; Fritsche, Ellen

    2012-05-01

    The 7th Amendment to the EU Cosmetics Directive prohibits the use of animals in cosmetic testing for certain endpoints, such as genotoxicity. Therefore, skin in vitro models have to replace chemical testing in vivo. However, the metabolic competence neither of human skin nor of alternative in vitro models has so far been fully characterized, although skin is the first-pass organ for accidentally or purposely (cosmetics and pharmaceuticals) applied chemicals. Thus, there is an urgent need to understand the xenobiotic-metabolizing capacities of human skin and to compare these activities to models developed to replace animal testing. We have measured the activity of the phase II enzymes glutathione S-transferase, UDP-glucuronosyltransferase and N-acetyltransferase in ex vivo human skin, the 3D epidermal model EpiDerm 200 (EPI-200), immortalized keratinocyte-based cell lines (HaCaT and NCTC 2544) and primary normal human epidermal keratinocytes. We show that all three phase II enzymes are present and highly active in skin as compared to phase I. Human skin, therefore, represents a more detoxifying than activating organ. This work systematically compares the activities of three important phase II enzymes in four different in vitro models directly to human skin. We conclude from our studies that 3D epidermal models, like the EPI-200 employed here, are superior over monolayer cultures in mimicking human skin xenobiotic metabolism and thus better suited for dermatotoxicity testing. PMID:22509834

  17. Reactive Arthritis Diagnosis

    MedlinePlus

    ... Of Spondylitis The Heart In Spondyloarthritis Inflammatory vs. Mechanical Back ... Arthritis Symptoms Because there is no specific laboratory test for reactive arthritis, doctors sometimes find it difficult ...

  18. Skin Aging

    MedlinePlus

    ... too. Sunlight is a major cause of skin aging. You can protect yourself by staying out of ... person has smoked. Many products claim to revitalize aging skin or reduce wrinkles, but the Food and ...

  19. Skin lumps

    MedlinePlus

    ... and contains fluid or semisolid material Benign skin growths such as seborrheic keratoses or neurofibromas Boils , painful, red bumps usually involving an infected hair follicle Corn or callus, caused by skin thickening in response ...

  20. Skin Pigment

    MedlinePlus

    ... Professional Version Pigment Disorders Overview of Skin Pigment Albinism Vitiligo Hyperpigmentation Melasma Melanin is the brown pigment ... dark-skinned people produce the most. People with albinism have little or no melanin and thus their ...

  1. Summary of Radionuclide Reactive Transport Experiments in Fractured Tuff and Carbonate Rocks from Yucca Flat, Nevada Test Site

    SciTech Connect

    Zavarin, M; Roberts, S; Reimus, P; Johnson, M

    2006-10-11

    In the Yucca Flat basin of the Nevada Test Site (NTS), 747 shaft and tunnel nuclear detonations were conducted primarily within the tuff confining unit (TCU) or the overlying alluvium. The TCU in the Yucca Flat basin is hypothesized to inhibit radionuclide migration to the highly transmissive and regionally extensive lower carbonate aquifer (LCA) due to its wide-spread aerial extent, low permeability, and chemical reactivity. However, fast transport pathways through the TCU by way of fractures may provide a migration path for radionuclides to the LCA. Radionuclide transport in both TCU and the LCA fractures is likely to determine the location of the contaminant boundary for the Yucca Flat/Climax Mine Corrective Action Unit (CAU). Radionuclide transport through the TCU may involve both matrix and fracture flow. However, radionuclide migration over significant distances is likely to be dominated by fracture transport. Transport through the LCA will almost certainly be dominated by fracture flow, as the LCA has a very dense, low porosity matrix with very low permeability. Because of the complex nature of reactive transport in fractures, a stepwise approach to identifying mechanisms controlling radionuclide transport was used. The simplest LLNL experiments included radionuclide transport through synthetic parallel-plate fractured tuff and carbonate cores. These simplified fracture transport experiments isolated matrix diffusion and sorption effects from all other fracture transport processes (fracture lining mineral sorption, heterogeneous flow, etc.). Additional fracture transport complexity was added by performing induced fractured LCA flowthrough experiments (effect of aperture heterogeneity) or iron oxide coated parallel plate TCU flowthrough experiments (effect of fracture lining minerals). Finally naturally fractured tuff and carbonate cores were examined at LLNL and LANL. All tuff and carbonate core used in the experiments was obtained from the USGS Core Library

  2. Skin graft

    MedlinePlus

    ... caused a large amount of skin loss Burns Cosmetic reasons or reconstructive surgeries where there has been skin damage or skin ... anesthesia are: Reactions to medicines Problems with breathing Risks for this surgery are: Bleeding Chronic pain (rarely) Infection Loss of ...

  3. Skin Aging

    MedlinePlus

    Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it ... heal, too. Sunlight is a major cause of skin aging. You can protect yourself by staying out ...

  4. Sensitization phenomena on aged SAF 2205 duplex stainless steel and their control using the electrochemical potentiokinetic reactivation test

    SciTech Connect

    Angelini, E.; Benedetti, B. de; Maizza, G.; Rosalbino, F. . Dept. of Materials Science and Chemical Engineering)

    1999-06-01

    Microstructural changes and resulting properties were studied for SAF 2205 (UNS S31803) austeno-ferritic stainless steel (SS) aged between 700 C and 900 C for up to 2 weeks and then water-quenched. Quantitative metallography coupled with x-ray diffraction techniques were adopted to follow ferrite ([alpha]) transformation with subsequent formation of secondary austenite ([gamma][sub 2]) and sigma ([sigma]) phase. The kinetic model of a transformation was interpreted in the form of an Avrami-type expression. The electrochemical potentiokinetic reactivation (EPR) test was used to evaluate the degree of sensitization of the aged specimens. Results were compared with results from the corrosion test in boiling nitric acid (HNO[sub 3]). Influences of the transformation of ferrite into austenite, sigma phase, and of other microstructural variations such as chromium nitride (Cr[sub 2]N) precipitation on stability of the passive film were shown. The susceptibility to intergranular corrosion phenomena was caused by chromium depletion caused by sigma phase precipitation, while chromium nitrides appeared less harmful. Results were expressed as an isocharge line diagram that allowed concise identification of sensitization and desensitization ranges.

  5. Column test-based optimization of the permeable reactive barrier (PRB) technique for remediating groundwater contaminated by landfill leachates

    NASA Astrophysics Data System (ADS)

    Zhou, Dan; Li, Yan; Zhang, Yinbo; Zhang, Chang; Li, Xiongfei; Chen, Zhiliang; Huang, Junyi; Li, Xia; Flores, Giancarlo; Kamon, Masashi

    2014-11-01

    We investigated the optimum composition of permeable reactive barrier (PRB) materials for remediating groundwater heavily contaminated by landfill leachate, in column tests using various mixtures of zero-valent iron (ZVI), zeolite (Zeo) and activated carbon (AC) with 0.01-0.25, 3.0-5.0 and 0.7-1.0 mm grain sizes, respectively. The main contributors to the removal of organic/inorganic contaminants were ZVI and AC, and the optimum weight ratio of the three PRB materials for removing the contaminants and maintaining adequate hydraulic conductivity was found to be 5:1:4. Average reductions in chemical oxygen demand (COD) and contents of total nitrogen (TN), ammonium, Ni, Pb and 16 polycyclic aromatic hydrocarbons (PAHs) from test samples using this mixture were 55.8%, 70.8%, 89.2%, 70.7%, 92.7% and 94.2%, respectively. We also developed a systematic method for estimating the minimum required thickness and longevity of the PRB materials. A ≥ 309.6 cm layer with the optimum composition is needed for satisfactory longevity, defined here as meeting the Grade III criteria (the Chinese National Bureau of Standards: GB/T14848/93) for in situ treatment of the sampled groundwater for ≥ 10 years.

  6. A bioanalytical HPLC method for coumestrol quantification in skin permeation tests followed by UPLC-QTOF/HDMS stability-indicating method for identification of degradation products.

    PubMed

    Bianchi, Sara E; Teixeira, Helder F; Kaiser, Samuel; Ortega, George G; Schneider, Paulo Henrique; Bassani, Valquiria L

    2016-05-01

    Coumestrol is present in several species of the Fabaceae family widely distributed in plants. The estrogenic and antioxidant activities of this molecule show its potential as skin anti-aging agent. These characteristics reveal the interest in developing analytical methodology for permeation studies, as well as to know the stability of coumestrol identifying the major degradation products. Thus, the present study was designed, first, to develop and validate a versatile liquid chromatography (HPLC) method to quantify coumestrol in a hydrogel formulation in different porcine skin layers (stratum corneum, epidermis, and dermis) in permeation tests. In the stability-indicating test coumestrol samples were exposed to stress conditions: temperature, UVC light, oxidative, acid and alkaline media. The degradation products, as well as the constituents extracted from the hydrogel, adhesive tape or skin were not eluted in the retention time of the coumestrol. Hence, the HPLC method showed to be versatile, specific, accurate, precise and robust showing excellent performance for quantifying coumestrol in complex matrices involving skin permeation studies. Coumestrol recovery from porcine ear skin was found to be in the range of 97.07-107.28μg/mL; the intra-day precision (repeatability) and intermediate precision (inter-day precision), respectively lower than 4.71% and 2.09%. The analysis using ultra-performance liquid chromatography coupled to a quadrupole time-of-flight high definition mass spectrometry detector (UPLC-QTOF/HDMS) suggest the MS fragmentation patterns and the chemical structure of the main degradation products. These results represent new and relevant findings for the development of coumestrol pharmaceutical and cosmetic products. PMID:27010353

  7. Performance of QuantiFERON-TB Gold In-Tube test and Tuberculin Skin Test for diagnosis of latent tuberculosis infection in BCG vaccinated health care workers

    PubMed Central

    Babayigit, Cenk; Ozer, Burcin; Inandi, Tacettin; Ozer, Cahit; Duran, Nizami; Gocmen, Orhan

    2014-01-01

    Background Tuberculin skin test (TST) has been used for years as an aid in diagnosing latent tuberculosis infection (LTBI) but it suffers from a number of well-documented performance and logistic problems. Quantiferon-TB Gold In Tube test (QFT-GIT) has been reported to have better sensitivity and specifity than TST. In this study, it was aimed to compare the performance of a commercial IFN-γ release assay (QFT-GIT) with TST in the diagnosis of HCWs at risk for latent TB infection in BCG vaccinated population. Material/Methods Hundred healthy volunteer health care workers were enrolled. All were subjected to TST and QFT-GIT. Results were compared among Health Care Workers (HCWs) groups in terms of profession, workplace, working duration. Results TST is affected by previous BCG vaccinations and number of cases with QFT-GIT positivity is increased in accordance with the TST induration diameter range. QFT-GIT result was negative in 17 of 32 TST positive (≥15 mm) cases and positive in 4 of 61 cases whose TST diameters are between 6–14 mm, that is attritutable to previous BCG vaccination(s). It was negative in all cases with TST diameters between 0–5 mm. HCWs with positive QFT-GIT results were significantly older than the ones with negative results. Furthermore duration of work was significantly longer in QFT-GIT positive than in negative HCWs. Conclusions There was a moderate concordance between QFT-GIT and TST, when TST result was defined as positive with a ≥15 mm diameter of induration. We suggest that QFT-GIT can be used as an alternative to TST for detection of LTBI, especially in groups with high risk of LTBI and in population with routine BCG vaccination program. PMID:24681806

  8. The direct peptide reactivity assay: selectivity of chemical respiratory allergens.

    PubMed

    Lalko, Jon F; Kimber, Ian; Gerberick, G Frank; Foertsch, Leslie M; Api, Anne Marie; Dearman, Rebecca J

    2012-10-01

    It is well known that some chemicals are capable of causing allergic diseases of the skin and respiratory tract. Commonly, though not exclusively, chemical allergens are associated with the selective development of skin or respiratory sensitization. The reason for this divergence is unclear, although it is hypothesized that the nature of interactions between the chemical hapten and proteins is influential. The direct peptide reactivity assay (DPRA) has been developed as a screen for the identification of skin-sensitizing chemicals, and here we describe the use of this method to explore whether differences exist between skin and respiratory allergens with respect to their peptide-binding properties. Known skin and respiratory sensitizers were reacted with synthetic peptides containing either lysine (Lys) or cysteine (Cys) for 24 h. The samples were analyzed by HPLC/UV, and the loss of peptide from the reaction mixture was expressed as the percent depletion compared with the control. The potential for preferential reactivity was evaluated by comparing the ratio of Lys to Cys depletion (Lys:Cys ratio). The results demonstrate that the majority of respiratory allergens are reactive in the DPRA, and that in contrast to most skin-sensitizing chemicals, preferentially react with the Lys peptide. These data suggest that skin and respiratory chemical allergens can result in different protein conjugates, which may in turn influence the quality of induced immune responses. Overall, these investigations reveal that the DPRA has considerable potential to be incorporated into tiered testing approaches for the identification and characterization of chemical respiratory allergens. PMID:22713598

  9. Quantification of chemical peptide reactivity for screening contact allergens: a classification tree model approach.

    PubMed

    Gerberick, G Frank; Vassallo, Jeffrey D; Foertsch, Leslie M; Price, Brad B; Chaney, Joel G; Lepoittevin, Jean-Pierre

    2007-06-01

    In the interest of reducing animal use, in vitro alternatives for skin sensitization testing are under development. One unifying characteristic of chemical allergens is the requirement that they react with proteins for the effective induction of skin sensitization. The majority of chemical allergens are electrophilic and react with nucleophilic amino acids. To determine whether and to what extent reactivity correlates with skin sensitization potential, 82 chemicals comprising allergens of different potencies and nonallergenic chemicals were evaluated for their ability to react with reduced glutathione (GSH) or with two synthetic peptides containing either a single cysteine or lysine. Following a 15-min reaction time with GSH, or a 24-h reaction time with the two synthetic peptides, the samples were analyzed by high-performance liquid chromatography. UV detection was used to monitor the depletion of GSH or the peptides. The peptide reactivity data were compared with existing local lymph node assay data using recursive partitioning methodology to build a classification tree that allowed a ranking of reactivity as minimal, low, moderate, and high. Generally, nonallergens and weak allergens demonstrated minimal to low peptide reactivity, whereas moderate to extremely potent allergens displayed moderate to high peptide reactivity. Classifying minimal reactivity as nonsensitizers and low, moderate, and high reactivity as sensitizers, it was determined that a model based on cysteine and lysine gave a prediction accuracy of 89%. The results of these investigations reveal that measurement of peptide reactivity has considerable potential utility as a screening approach for skin sensitization testing, and thereby for reducing reliance on animal-based test methods. PMID:17400584

  10. Validation study of the in vitro skin irritation test with the LabCyte EPI-MODEL24.

    PubMed

    Kojima, Hajime; Ando, Yoko; Idehara, Kenji; Katoh, Masakazu; Kosaka, Tadashi; Miyaoka, Etsuyoshi; Shinoda, Shinsuke; Suzuki, Tamie; Yamaguchi, Yoshihiro; Yoshimura, Isao; Yuasa, Atsuko; Watanabe, Yukihiko; Omori, Takashi

    2012-03-01

    A validation study on an in vitro skin irritation assay was performed with the reconstructed human epidermis (RhE) LabCyte EPI-MODEL24, developed by Japan Tissue Engineering Co. Ltd (Gamagori, Japan). The protocol that was followed in the current study was an optimised version of the EpiSkin protocol (LabCyte assay). According to the United Nations Globally Harmonised System (UN GHS) of classification for assessing the skin irritation potential of a chemical, 12 irritants and 13 non-irritants were validated by a minimum of six laboratories from the Japanese Society for Alternatives to Animal Experiments (JSAAE) skin irritation assay validation study management team (VMT). The 25 chemicals were listed in the European Centre for the Validation of Alternative Methods (ECVAM) performance standards. The reconstructed tissues were exposed to the chemicals for 15 minutes and incubated for 42 hours in fresh culture medium. Subsequently, the level of interleukin-1 alpha (IL-1 α) present in the conditioned medium was measured, and tissue viability was assessed by using the MTT assay. The results of the MTT assay obtained with the LabCyte EPI-MODEL24 (LabCyte MTT assay) demonstrated high within-laboratory and between-laboratory reproducibility, as well as high accuracy for use as a stand-alone assay to distinguish skin irritants from non-irritants. In addition, the IL-1α release measurements in the LabCyte assay were clearly unnecessary for the success of this model in the classification of chemicals for skin irritation potential. PMID:22558976

  11. NASA Glenn's Engine Components Research Lab, Cell 2B, Reactivated to Support the U.S. Army Research Laboratory T700 Engine Test

    NASA Technical Reports Server (NTRS)

    Beltran, Luis R.; Griffin, Thomas A.

    2004-01-01

    The U.S. Army Vehicle Technology Directorate at the NASA Glenn Research Center has been directed by their parent command, the U.S. Army Research Laboratory (ARL), to demonstrate active stall technology in a turboshaft engine as the next step in transitioning this technology to the Army and aerospace industry. Therefore, the Vehicle Technology Directorate requested the reactivation of Glenn's Engine Components Research Lab, Cell 2B, (ECRL 2B). They wanted to test a T700 engine that had been used previously for turboshaft engine research as a partnership between the Army and NASA on small turbine engine research. ECRL 2B had been placed in standby mode in 1997. Glenn's Testing Division initiated reactivation in May 2002 to support the new research effort, and they completed reactivation and improvements in September 2003.

  12. Sensitive skin.

    PubMed

    Misery, L; Loser, K; Ständer, S

    2016-02-01

    Sensitive skin is a clinical condition defined by the self-reported facial presence of different sensory perceptions, including tightness, stinging, burning, tingling, pain and pruritus. Sensitive skin may occur in individuals with normal skin, with skin barrier disturbance, or as a part of the symptoms associated with facial dermatoses such as rosacea, atopic dermatitis and psoriasis. Although experimental studies are still pending, the symptoms of sensitive skin suggest the involvement of cutaneous nerve fibres and neuronal, as well as epidermal, thermochannels. Many individuals with sensitive skin report worsening symptoms due to environmental factors. It is thought that this might be attributed to the thermochannel TRPV1, as it typically responds to exogenous, endogenous, physical and chemical stimuli. Barrier disruptions and immune mechanisms may also be involved. This review summarizes current knowledge on the epidemiology, potential mechanisms, clinics and therapy of sensitive skin. PMID:26805416

  13. Effects of Serial Skin Testing with Purified Protein Derivative on the Level and Quality of Antibodies to Complex and Defined Antigens in Mycobacterium bovis-Infected Cattle

    PubMed Central

    Palmer, Mitchell V.; Stafne, Molly R.; Bass, Kristin E.; Maggioli, Mayara F.; Thacker, Tyler C.; Linscott, Rick; Lawrence, John C.; Nelson, Jeffrey T.; Esfandiari, Javan; Greenwald, Rena; Lyashchenko, Konstantin P.

    2015-01-01

    Several serological tests designed to detect antibodies to immunodominant Mycobacterium bovis antigens have recently emerged as ancillary tests for the detection of bovine tuberculosis in cattle, particularly when used after the injection of purified protein derivative (PPD) for skin testing, which significantly boosts M. bovis-specific antibody responses. The present findings demonstrate the onset and duration of boosted antibody responses after the injection of M. bovis PPD for the caudal fold test (CFT) and Mycobacterium avium and M. bovis PPDs for the comparative cervical test (CCT), administered in series in cattle experimentally infected with M. bovis. While skin tests boosted the responses to certain antigens (i.e., MPB83 and MPB70), they did not affect the responses to other antigens (e.g., ESAT-6, CFP10, MPB59, and MPB64). Administration of the CCT 105 days after the CFT resulted in an even greater secondary boost in antibody responses to MPB83 and MPB70 and to a proteinase K-digested whole-cell sonicate (WCS-PK) of M. bovis. Both IgM and IgG contributed to the initial boost in the MPB83/MPB70-specific antibody response after the CFT. The secondary boost after the CCT was primarily due to increased IgG levels. Also, the avidity of antibodies to MPB83 and MPB70 increased after the CCT in M. bovis-infected cattle. The avidity of antibodies to the WCS-PK antigens increased in the interval between the CFT and the CCT but did not increase further after the CCT. Together, these findings demonstrate that the administration of PPDs for skin tests results in additive enhancement (i.e., when the CFT and CCT are performed in series), both qualitative and quantitative, of MPB83/MPB70-specific antibody responses. PMID:25855555

  14. Reaction of glycation and human skin: the effects on the skin and its components, reconstructed skin as a model.

    PubMed

    Pageon, H

    2010-06-01

    Skin is affected by the aging process and numerous modifications are observed. In human, with time the skin becomes drier, thinner, spots appear, elasticity decreases and stiffening increases, together with the appearance of wrinkles. These observations result from the overlapping of an intrinsic chronological aging (individual, genetic) and of an extrinsic aging (dependent on external factors like UV, pollution and lifestyle). One of the causes of aging is the appearance of the Advanced Glycosylation End Products (AGEs) during life. The glycation reaction results from a non-enzymatic reaction between a sugar and a free amine group of Lys, Arg amino acids in proteins. This reaction does not occur only in the skin, indeed, AGEs are also found in the kidney, lens, vessels, etc. These products are also responsible, because of their localization, of some pathologies related to diabetes. AGEs provoke biological modifications implying an activation of molecules synthesis (extracellular matrix, cytokines) and enzyme activation of matrix degradation (metalloproteinases). The UV effect on AGEs (like pentosidine) generates reactive oxygen species (ROS) in the extracellular matrix which could lead to additional deleterious effects. Molecules are described in the literature as inhibitors to this irreversible reaction i.e. aminoguanidine. To understand the consequences of the glycation in the skin, a system of reconstructed skin was developed with a collagen modified by glycation for the dermal component. In this system we observed that dermis and epidermis are both modified due to glycation (macromolecules synthesis, cytokines, metalloproteinases) and it is possible to test inhibitors of this reaction. In conclusion, in skin, glycation is involved in a very complex aging process and simultaneously affect, directly and indirectly, certain cells, their synthesis and the organization of the matrix. PMID:19896301

  15. Towards label-free evaluation of oxidative stress in human skin exposed to sun filters (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Osseiran, Sam; Wang, Hequn; Suita, Yusuke; Roider, Elisabeth; Fisher, David E.; Evans, Conor L.

    2016-02-01

    Skin cancer, including basal cell carcinoma, squamous cell carcinoma, and melanoma, is the most common form of cancer in North America. Paradoxically, skin cancer incidence is steadily on the rise even despite the growing use of sunscreens over the past decades. One potential explanation for this discrepancy involves the sun filters in sunscreen, which are responsible for blocking harmful ultraviolet radiation. It is proposed that these agents may produce reactive oxygen species (ROS) at the site of application, thereby generating oxidative stress in skin that gives rise to genetic mutations, which may explain the rising incidence of skin cancer. To test this hypothesis, ex vivo human skin was treated with five common chemical sun filters (avobenzone, octocrylene, homosalate, octisalate, and oxybenzone) as well as two physical sun filters (zinc oxide compounds), both with and without UV irradiation. To non-invasively evaluate oxidative stress, two-photon excitation fluorescence (2PEF) and fluorescence lifetime imaging microscopy (FLIM) of the skin samples were used to monitor levels of NADH and FAD, two key cofactors in cellular redox metabolism. The relative redox state of the skin was assessed based on the fluorescence intensities and lifetimes of these endogenous cofactors. While the sun filters were indeed shown to have a protective effect from UV radiation, it was observed that they also generate oxidative stress in skin, even in the absence of UV light. These results suggest that sun filter induced ROS production requires more careful study, especially in how these reactive species impact the rise of skin cancer.

  16. A Randomised Test of Printed Educational Materials about Melanoma Detection: Varying Skin Self-Examination Technique and Visual Image Dose

    ERIC Educational Resources Information Center

    King, Andy J.; Carcioppolo, Nick; Grossman, Douglas; John, Kevin K.; Jensen, Jakob D.

    2015-01-01

    Objective: Melanoma incidence and mortality rates continue to rise globally, making it essential for researchers to identify effective approaches to disseminating information to the public that improve key outcomes. This study compared two skin self-examination (SSE) educational strategies: the ABCDE (asymmetry, border irregularity, multiple…

  17. MULTISPECIES REACTIVE TRACER TEST IN A SAND AND GRAVEL AQUIFER, CAPE COD, MASSACHUSETTS: PART 2: TRANSPORT OF CHROMIUM (VI) AND LEAD-, COPPER-, AND ZINC-EDTA TRACERS

    EPA Science Inventory

    This report discusses the transport of a group of reactive tracers over the course of a large-scale, natural gradient tracer test conducted at the USGS Cape Cod Toxic Substances Hydrology Research site, near Falmouth, Massachusetts. The overall objectives of the experiment were ...

  18. THE APPLICATION OF IN SITU PERMEABLE REACTIVE (ZERO-VALENT IRON) BARRIER TECHNOLOGY FOR THE REMEDIATION OF CHROMATE-CONTAMINATED GROUNDWATER: A FIELD TEST

    EPA Science Inventory

    A small-scale field test was initiated in September 1994 to evaluate the in situ remediation of groundwater contaminated with chromate using a permeable reactive barrier composed of a mixture of zero-valent Fe, sand and aquifer sediment. The site used was an old chrome-plating f...

  19. Tuberculin Skin Test Reversion following Isoniazid Preventive Therapy Reflects Diversity of Immune Response to Primary Mycobacterium tuberculosis Infection

    PubMed Central

    Johnson, Denise F.; Malone, LaShaunda L.; Zalwango, Sarah; Mukisa Oketcho, Joy; Chervenak, Keith A.; Thiel, Bonnie; Mayanja-Kizza, Harriet; Stein, Catherine M.; Boom, W. Henry; Lancioni, Christina L.

    2014-01-01

    Rationale Healthy household contacts (HHC) of individuals with Tuberculosis (TB) with Tuberculin Skin Test (TST) conversions are considered to harbor latent Mycobacterium tuberculosis (Mtb), and at risk for TB. The immunologic, clinical, and public health implications of TST reversions that occur following Isoniazid preventive therapy (IPT) remain controversial. Objectives To measure frequency of TST reversion following IPT, and variation in interferon-gamma (IFN-γ) responses to Mtb, in healthy Ugandan TB HHC with primary Mtb infection evidenced by TST conversion. Methods Prospective cohort study of healthy, HIV-uninfected, TST-negative TB HHC with TST conversions. Repeat TST was performed 12 months following conversion (3 months following completion of 9 month IPT course) to assess for stable conversion vs. reversion. Whole blood IFN-γ responses to Mtb antigen 85B (MtbA85B) and whole Mtb bacilli (wMtb) were measured in a subset (n = 27 and n = 42, respectively) at enrollment and TST conversion, prior to initiation of IPT. Results Of 122 subjects, TST reversion was noted in 25 (20.5%). There were no significant differences in demographic, clinical, or exposure variables between reverters and stable converters. At conversion, reverters had significantly smaller TST compared to stable converters (13.7 mm vs 16.4 mm, respectively; p = 0.003). At enrollment, there were no significant differences in IFN-γ responses to MtbA85B or wMTB between groups. At conversion, stable converters demonstrated significant increases in IFN-γ responses to Ag85B and wMtb compared to enrollment (p = 0.001, p<0.001, respectively), while there were no significant changes among reverters. Conclusions TST reversion following IPT is common following primary Mtb infection and associated with unique patterns of Mtb-induced IFN-γ production. We have demonstrated that immune responses to primary Mtb infection are heterogeneous, and submit that prospective longitudinal studies

  20. Skin aging and dry skin.

    PubMed

    Hashizume, Hideo

    2004-08-01

    Skin aging appears to be the result of both scheduled and continuous "wear and tear" processes that damage cellular DNA and proteins. Two types of aging, chronological skin aging and photoaging, have distinct clinical and histological features. Chronological skin aging is a universal and inevitable process characterized primarily by physiologic alterations in skin function. In this case, keratinocytes are unable to properly terminally differentiate to form a functional stratum corneum, and the rate of formation of neutral lipids that contribute to the barrier function slows, causing dry, pale skin with fine wrinkles. In contrast, photoaging results from the UVR of sunlight and the damage thus becomes apparent in sun-exposed skin. Characteristics of this aging type are dry and sallow skin displaying fine wrinkles as well as deep furrows, resulting from the disorganization of epidermal and dermal components associated with elastosis and heliodermatitis. Understanding of the functions of the skin and the basic principles of moisturizer use and application is important for the prevention of skin aging. Successful treatment of dry skin with appropriate skin care products gives the impression of eternal youth. PMID:15492432

  1. Biological effects of rutin on skin aging.

    PubMed

    Choi, Seong Jin; Lee, Sung-Nae; Kim, Karam; Joo, Da Hye; Shin, Shanghun; Lee, Jeongju; Lee, Hyun Kyung; Kim, Jihyun; Kwon, Seung Bin; Kim, Min Jung; Ahn, Kyu Joong; An, In-Sook; An, Sungkwan; Cha, Hwa Jun

    2016-07-01

    Rutin, a quercetin glycoside is a member of the bioflavonoid family which is known to possess antioxidant properties. In the present study, we aimed to confirm the anti‑aging effects of rutin on human dermal fibroblasts (HDFs) and human skin. We examined the effects of rutin using a cell viability assay, senescence-associated-β-galactosidase assay, reverse transcription-quantitative polymerase chain reaction, and by measuring reactive oxygen species (ROS) scavenging activity in vitro. To examine the effects of rutin in vivo, rutin‑containing cream was applied to human skin. A double-blind clinical study was conducted in 40 subjects aged between 30-50 years and divided into control and experimental groups. The test material was applied for 4 weeks. After 2 and 4 weeks, dermal density, skin elasticity, the length and area of crow's feet, and number of under-eye wrinkles following the application of either the control or the rutin-containing cream were analyzed. Rutin increased the mRNA expression of collagen, type I, alpha 1 (COL1A1) and decreased the mRNA expression of matrix metallopeptidase 1 (MMP1) in HDFs. We verified that ROS scavenging activity was stimulated by rutin in a dose‑dependent manner and we identified that rutin exerted protective effects under conditions of oxidative stress. Furthermore, rutin increased skin elasticity and decreased the length, area and number of wrinkles. The consequences of human aging are primarily visible on the skin, such as increased wrinkling, sagging and decreased elasticity. Overall, this study demonstrated the biological effects of rutin on ROS-induced skin aging. PMID:27220601

  2. Permeable Reactive Biobarriers for In Situ Cr(VI) Reduction: Bench Scale Tests Using Cellulomonas sp. Strain ES6

    SciTech Connect

    Sridhar Viamajala; Brent M. Peyton; Robin Gerlach; Vaideeswaran; William A. Apel; James N. Petersen

    2008-12-01

    Chromate (Cr(VI)) reduction studies were performed in bench scale flow columns using the fermentative subsurface isolate Cellulomonas sp. strain ES6. In these tests, columns packed with either quartz sand or hydrous ferric oxide (HFO)-coated quartz sand, were inoculated with strain ES6 and fed nutrients to stimulate growth before nutrient-free Cr(VI) solutions were injected. Results show that in columns containing quartz sand, a continuous inflow of 2 mg/L Cr(VI) was reduced to below detection limits in the effluent for durations of up to 5.7 residence times after nutrient injection was discontinued proving the ability of strain ES6 to reduce chromate in the absence of an external electron donor. In the HFO-containing columns, Cr(VI) reduction was significantly prolonged and effluent Cr(VI) concentrations remained below detectable levels for periods of up to 66 residence times after nutrient injection was discontinued. Fe was detected in the effluent of the HFO-containing columns throughout the period of Cr(VI) removal indicating that the insoluble Fe(III) bearing solids were being continuously reduced to form soluble Fe(II) resulting in prolonged abiotic Cr(VI) reduction. Thus, growth of Cellulomonas within the soil columns resulted in formation of permeable reactive barriers that could reduce Cr(VI) and Fe(III) for extended periods even in the absence of external electron donors. Other bioremediation systems employing Fe(II)-mediated reactions require a continuous presence of external nutrients to regenerate Fe(II). After depletion of nutrients, contaminant removal within these systems occurs by reaction with surface-associated Fe(II) that can rapidly become inaccessible due to formation of crystalline Fe-minerals or other precipitates. The ability of fermentative organisms like Cellulomonas to reduce metals without continuous nutrient supply in the subsurface offers a viable and economical alternative technology for in situ remediation of Cr

  3. Permeable reactive biobarriers for in situ Cr(VI) reduction: bench scale tests using Cellulomonas sp. strain ES6.

    PubMed

    Viamajala, Sridhar; Peyton, Brent M; Gerlach, Robin; Sivaswamy, Vaideeswaran; Apel, William A; Petersen, James N

    2008-12-15

    Chromate (Cr(VI)) reduction studies were performed in bench scale flow columns using the fermentative subsurface isolate Cellulomonas sp. strain ES6. In these tests, columns packed with either quartz sand or hydrous ferric oxide (HFO)-coated quartz sand, were inoculated with strain ES6 and fed nutrients to stimulate growth before nutrient-free Cr(VI) solutions were injected. Results show that in columns containing quartz sand, a continuous inflow of 2 mg/L Cr(VI) was reduced to below detection limits in the effluent for durations of up to 5.7 residence times after nutrient injection was discontinued proving the ability of strain ES6 to reduce chromate in the absence of an external electron donor. In the HFO-containing columns, Cr(VI) reduction was significantly prolonged and effluent Cr(VI) concentrations remained below detectable levels for periods of up to 66 residence times after nutrient injection was discontinued. Fe was detected in the effluent of the HFO-containing columns throughout the period of Cr(VI) removal indicating that the insoluble Fe(III) bearing solids were being continuously reduced to form soluble Fe(II) resulting in prolonged abiotic Cr(VI) reduction. Thus, growth of Cellulomonas within the soil columns resulted in formation of permeable reactive barriers that could reduce Cr(VI) and Fe(III) for extended periods even in the absence of external electron donors. Other bioremediation systems employing Fe(II)-mediated reactions require a continuous presence of external nutrients to regenerate Fe(II). After depletion of nutrients, contaminant removal within these systems occurs by reaction with surface-associated Fe(II) that can rapidly become inaccessible due to formation of crystalline Fe-minerals or other precipitates. The ability of fermentative organisms like Cellulomonas to reduce metals without continuous nutrient supply in the subsurface offers a viable and economical alternative technology for in situ remediation of Cr

  4. In vivo photochemical skin micronucleus test using a sunlight simulator: detection of 8-methoxypsoralen and benzo[a]pyrene in hairless mice.

    PubMed

    Hara, Takumi; Nishikawa, Takashi; Sui, Hajime; Kawakami, Kumiko; Matsumoto, Hirotaka; Tanaka, Noriho

    2007-07-10

    Evaluating in vivo photochemical genotoxicity (photogenotoxicity) or photochemical carcinogenicity (photocarcinogenicity) in the skin that is actually exposed to light is important for estimating the risk of human exposure to chemicals under sunlight. With regard to the skin micronucleus test, Nishikawa et al. developed a reliable technique that is simple and in which the negative control has a stable background. In the present study, we applied 8-methoxypsoralen (8-MOP) and benzo[a]pyrene (B[a]P) to the backs of hairless mice and subjected the mice to irradiation by a sunlight simulator in order to investigate whether this test can detect photogenotoxicity of these chemicals. In the treatment with 8-MOP [0.00075% and 0.0015% (w/v)], a significant increase was observed in the frequency of micronucleated cells only under light irradiation using the sunlight simulator. At a high chemical dose, the frequency of micronucleated cells increased from 48h after the treatment, peaked at 96h, and then decreased at 168h. Furthermore, at 96h with the high dose under light irradiation, we frequently observed cells with nuclear buds. In the treatment with B[a]P [first experiment: 0.025% and 0.05% (w/v); second experiment: 0.005%, 0.01%, and 0.02% (w/v)], a significant increase was observed in the frequency of micronucleated cells at skin-irritating doses [0.01%, 0.02%, 0.025%, and 0.05% (w/v)] at 72 or 96h after the treatment only under light irradiation using the sunlight simulator. In conclusion, photogenotoxicity of 8-MOP and B[a]P was detected in the in vivo photochemical skin micronucleus study. PMID:17512241

  5. Xenobiotic metabolism capacities of human skin in comparison with a 3D epidermis model and keratinocyte-based cell culture as in vitro alternatives for chemical testing: activating enzymes (Phase I).

    PubMed

    Götz, Christine; Pfeiffer, Roland; Tigges, Julia; Blatz, Veronika; Jäckh, Christine; Freytag, Eva-Maria; Fabian, Eric; Landsiedel, Robert; Merk, Hans F; Krutmann, Jean; Edwards, Robert J; Pease, Camilla; Goebel, Carsten; Hewitt, Nicola; Fritsche, Ellen

    2012-05-01

    Skin is important for the absorption and metabolism of exposed chemicals such as cosmetics or pharmaceuticals. The Seventh Amendment to the EU Cosmetics Directive prohibits the use of animals for cosmetic testing for certain endpoints, such as genotoxicity; therefore, there is an urgent need to understand the xenobiotic metabolizing capacities of human skin and to compare these activities with reconstructed 3D skin models developed to replace animal testing. We have measured Phase I enzyme activities of cytochrome P450 (CYP) and cyclooxygenase (COX) in ex vivo human skin, the 3D skin model EpiDerm™ (EPI-200), immortalized keratinocyte-based cell lines and primary normal human epidermal keratinocytes. Our data demonstrate that basal CYP enzyme activities are very low in whole human skin and EPI-200 as well as keratinocytes. In addition, activities in monolayer cells differed from organotypic tissues after induction. COX activity was similar in skin, EPI-200 and NHEK cells, but was significantly lower in immortalized keratinocytes. Hence, the 3D model EPI-200 might represent a more suitable model for dermatotoxicological studies. Altogether, these data help to better understand skin metabolism and expand the knowledge of in vitro alternatives used for dermatotoxicity testing. PMID:22509833

  6. Skin optics

    SciTech Connect

    van Gemert, M.J.; Jacques, S.L.; Sterenborg, H.J.; Star, W.M.

    1989-12-01

    Quantitative dosimetry in the treatment of skin disorders with (laser) light requires information on propagation of light in the skin related to the optical properties of the individual skin layers. This involves the solution of the integro-differential equation of radiative transfer in a model representing skin geometry, as well as experimental methods to determine the optical properties of each skin layer. These activities are unified under the name skin optics. This paper first reviews the current status of tissue optics, distinguishing between the cases of: dominant absorption, dominant scattering, and scattering about equal to absorption. Then, previously published data as well as some current unpublished data on (human) stratum corneum, epidermis and dermis, have been collected and/or (re)analyzed in terms of absorption coefficient, scattering coefficient, and anisotropy factor of scattering. The results are that the individual skin layers show strongly forward scattering (anisotropy factors between 0.7 and 0.9). The absorption and scattering data show that for all wavelengths considered scattering is much more important than absorption. Under such circumstances, solutions to the transport equation for a multilayer skin model and finite beam laser irradiation are currently not yet available. Hence, any quantitative dosimetry for skin treated with (laser) light is currently lacking.

  7. Penetration, photo-reactivity and photoprotective properties of nanosized ZnO.

    PubMed

    Detoni, C B; Coradini, K; Back, P; Oliveira, C M; Andrade, D F; Beck, R C R; Pohlmann, A R; Guterres, S S

    2014-09-01

    The oxidizing capacity and skin penetration of a commercial nanosized ZnO, Nanosun™ (Micronisers-Australia), were evaluated in vitro using porcine skin. Nanosun™ was initially characterized regarding its photo-reactivity and size distribution. An assay using methylene blue was performed to confirm the Nanosun™ photo-reactivity by exposing the labile molecule to UVA irradiation in the presence and absence of the nanosized ZnO. The nanosized ZnO was photo-reactive, reducing the methylene blue concentration to 7% while its concentration remained constant in the control formulation (without ZnO). The product label states that the average particle size is 30 nm. X-ray diffraction, nitrogen sorption and UV-spectrophotometry confirmed the presence of nanometric particles of approximately 30 nm. On the other hand, laser diffractometry showed micrometric particles in the size distribution profile. These analyses indicated that the nanoparticles are arranged as agglomerates and aggregates of micrometric proportions ranging from 0.6 to 60 μm. The skin lipid peroxidation was determined by the formation of thiobarbituric acid reactive species (TBARS) and quantified by UV-spectrophotometry. When exposed to UVA radiation the nanosized ZnO applied porcine skin showed a lower production of TBARS (7.2 ± 1.5 nmol g(-1)) than the controls, the MCT applied porcine skin (18.4 ± 2.8 nmol g(-1)) and the blank porcine skin (14.0 ± 2.0 nmol g(-1)). The penetration of ZnO nanoparticles was studied by scanning electron microscopy and energy dispersive X-ray spectroscopy. The tested ZnO particles did not penetrate into viable layers of the intact porcine skin. The particles tend to accumulate on the skin folds and in these regions they may penetrate into the horny layer. PMID:24977261

  8. Occupational skin disease.

    PubMed

    Peate, W E

    2002-09-15

    Contact dermatitis, the most common occupational skin disease, is characterized by clearly demarcated areas of rash at sites of exposure. The rash improves on removal of the offending agent. In allergic contact dermatitis, even minute exposures to antigenic substances can lead to a skin rash. Common sensitizing agents include nickel and members of the Rhus genus (e.g., poison ivy, poison oak). Severe skin irritants tend to cause immediate red blisters or burns, whereas weaker irritants produce eczematous skin changes over time. An occupational cause should be suspected when rash occurs in areas that are in contact with oil, grease, or other substances. Direct skin testing (patch or scratch) or radioallergosorbent testing may help to identify a specific trigger. Skin cancer can have an occupational link in workers with prolonged exposure to sunlight and certain chemicals, although it can take decades for lesions to develop. In workers with occupational skin disease, workplace changes and protective measures are important to prevent future exposure. PMID:12358214

  9. Fibre Diffraction Analysis of Skin Offers a Very Early and Extremely Accurate Diagnostic Test for Prostate Cancer

    DOE PAGESBeta

    James, Veronica J.; O’Malley Ford, Judith M.

    2014-01-01

    Double blind analysis of a batch of thirty skin tissue samples from potential prostate cancer sufferers correctly identified all “control” patients, patients with high and low grade prostate cancers, the presence of benign prostate hyperplasia (BPH), perineural invasions, and the one lymphatic invasion. Identification was by analysis of fibre diffraction patterns interpreted using a schema developed from observations in nine previous studies. The method, schema, and specific experiment results are reported in this paper, with some implications then drawn.

  10. Thermal Skin fabrication technology

    NASA Technical Reports Server (NTRS)

    Milam, T. B.

    1972-01-01

    Advanced fabrication techniques applicable to Thermal Skin structures were investigated, including: (1) chemical machining; (2) braze bonding; (3) diffusion bonding; and (4) electron beam welding. Materials investigated were nickel and nickel alloys. Sample Thermal Skin panels were manufactured using the advanced fabrication techniques studied and were structurally tested. Results of the program included: (1) development of improved chemical machining processes for nickel and several nickel alloys; (2) identification of design geometry limits; (3) identification of diffusion bonding requirements; (4) development of a unique diffusion bonding tool; (5) identification of electron beam welding limits; and (6) identification of structural properties of Thermal Skin material.

  11. Routine two-step skin testing for tuberculosis in the staff of a geriatric hospital in Israel: booster and conversion rates.

    PubMed

    Srour-Fihmi, S; Weiler-Ravell, D; Kitzes, R; Chemtob, D

    2000-10-01

    The objective of this study was to determine the prevalence of positive skin tests amongst the staff of a 200 bed geriatric hospital in Haifa, Israel. By comparing the findings with those of a study performed five years previously, we hoped to ascertain the number of conversions which had occurred in the period studied. This was undertaken in order to assess a new policy from the Israel Ministry of Health regarding skin testing for health care workers. We also hoped to decide upon the frequency of skin testing required and to compare data from recent immigrants from countries with a high prevalence of TB. In 1997, we performed two-step skin testing (TSST) on 318 health care workers. We ascertained the number of positive reactions on the first and second testing and calculated the number of subjects who showed significant boosting. We also compared the results to those obtained in a study in 1992 and calculated the rate of conversion. We used multivariate analysis to examine the effects of age, gender, country of origin, years in Israel, previous BCG vaccination, previous exposure to contagious TB, work site and area of residence in the city, on the response to TSST. Between 1990 and 1996, 655 000 immigrants from the former USSR arrived; 'recent immigration' was defined from that date onward. The final number of positive reactions out of 282 subjects, who were either positive or negative on step 1 and presented for step 2, was 171 (60%). Booster effect was not significantly associated with any of the variables examined. The size of reaction in TSST was related to country of origin and recent immigration. The 83 recent immigrants from the former USSR had more frequent (61%) and larger reactions (mean (sd): 9.0 (6.46) mm) than the 114 native-born Israelis with 39% positive reactions (6.2 (5.89) P= 0.009). Comparison with 1992 revealed 26 (31%) of previous negatives as positive. Conversion was associated with age. All conversions save one were in individuals younger

  12. Determination of MBT-waste reactivity - An infrared spectroscopic and multivariate statistical approach to identify and avoid failures of biological tests.

    PubMed

    Böhm, K; Smidt, E; Binner, E; Schwanninger, M; Tintner, J; Lechner, P

    2010-04-01

    The Austrian Landfill Ordinance provides limit values regarding the reactivity for the disposal of mechanically biologically treated (MBT) waste before landfilling. The potential reactivity determined by biological tests according to the Austrian Standards (OENORM S 2027 1-2) can be underestimated if the microbial community is affected by environmental conditions. New analytical tools have been developed as an alternative to error-prone and time-consuming biological tests. Fourier Transform Infrared (FT-IR) spectroscopy in association with Partial Least Squares Regression (PLS-R) was used to predict the reactivity parameters respiration activity (RA(4)) and gas generation sum (GS(21)) as well as to detect errors resulting from inhibiting effects on biological tests. For this purpose 250 MBT-waste samples from different Austrian MBT-plants were investigated using FT-IR spectroscopy in the mid (MIR) and near infrared (NIR) area and biological tests. Spectroscopic results were compared with those from biological tests. Arising problems caused by interferences of RA(4) and GS(21) are discussed. It is shown that FT-IR spectroscopy predicts RA(4) and GS(21) reliably to assess stability of MBT-waste materials and to detect errors. PMID:19854633

  13. Tuberculosis screening of new hospital employees: compliance, clearance to work time, and cost using tuberculin skin test and interferon-gamma release assays.

    PubMed

    Foster-Chang, Sarah A; Manning, Mary L; Chandler, Laura

    2014-11-01

    Selection of the most suitable test(s) for detection of Mycobacterium tuberculosis (TB) infection should be based on purpose, setting, effectiveness, and cost. Two tests are available to screen for latent TB: the tuberculin skin test (TST) and the more recent interferon-gamma release assays (IGRAs). Based on the administrative, logistic, and technical ease of use, an IGRA trial was initiated by the occupational health department at an urban Veteran's Administration health care facility for TB screening of new employees. As a result, new employees completing the pre-placement process within the organization's designated 14 days increased from 77% to 97%, new employee clearance to work time decreased from 13.18 to 5.91 days, and new employee TB screening costs were reduced by 40%. The IGRA is an acceptable alternative to the TST and has significant potential to improve the process of pre-placement TB screening. PMID:25207587

  14. Chip-based human liver-intestine and liver-skin co-cultures--A first step toward systemic repeated dose substance testing in vitro.

    PubMed

    Maschmeyer, Ilka; Hasenberg, Tobias; Jaenicke, Annika; Lindner, Marcus; Lorenz, Alexandra Katharina; Zech, Julie; Garbe, Leif-Alexander; Sonntag, Frank; Hayden, Patrick; Ayehunie, Seyoum; Lauster, Roland; Marx, Uwe; Materne, Eva-Maria

    2015-09-01

    Systemic repeated dose safety assessment and systemic efficacy evaluation of substances are currently carried out on laboratory animals and in humans due to the lack of predictive alternatives. Relevant international regulations, such as OECD and ICH guidelines, demand long-term testing and oral, dermal, inhalation, and systemic exposure routes for such evaluations. So-called "human-on-a-chip" concepts are aiming to replace respective animals and humans in substance evaluation with miniaturized functional human organisms. The major technical hurdle toward success in this field is the life-like combination of human barrier organ models, such as intestine, lung or skin, with parenchymal organ equivalents, such as liver, at the smallest biologically acceptable scale. Here, we report on a reproducible homeostatic long-term co-culture of human liver equivalents with either a reconstructed human intestinal barrier model or a human skin biopsy applying a microphysiological system. We used a multi-organ chip (MOC) platform, which provides pulsatile fluid flow within physiological ranges at low media-to-tissue ratios. The MOC supports submerse cultivation of an intact intestinal barrier model and an air-liquid interface for the skin model during their co-culture with the liver equivalents respectively at (1)/100.000 the scale of their human counterparts in vivo. To increase the degree of organismal emulation, microfluidic channels of the liver-skin co-culture could be successfully covered with human endothelial cells, thus mimicking human vasculature, for the first time. Finally, exposure routes emulating oral and systemic administration in humans have been qualified by applying a repeated dose administration of a model substance - troglitazone - to the chip-based co-cultures. PMID:25857839

  15. A catch-up validation study of an in vitro skin irritation test method using reconstructed human epidermis LabCyte EPI-MODEL24.

    PubMed

    Kojima, Hajime; Katoh, Masakazu; Shinoda, Shinsuke; Hagiwara, Saori; Suzuki, Tamie; Izumi, Runa; Yamaguchi, Yoshihiro; Nakamura, Maki; Kasahawa, Toshihiko; Shibai, Aya

    2014-07-01

    Three validation studies were conducted by the Japanese Society for Alternatives to Animal Experiments in order to assess the performance of a skin irritation assay using reconstructed human epidermis (RhE) LabCyte EPI-MODEL24 (LabCyte EPI-MODEL24 SIT) developed by the Japan Tissue Engineering Co., Ltd. (J-TEC), and the results of these studies were submitted to the Organisation for Economic Co-operation and Development (OECD) for the creation of a Test Guideline (TG). In the summary review report from the OECD, the peer review panel indicated the need to resolve an issue regarding the misclassification of 1-bromohexane. To this end, a rinsing operation intended to remove exposed chemicals was reviewed and the standard operating procedure (SOP) revised by J-TEC. Thereafter, in order to confirm general versatility of the revised SOP, a new validation management team was organized by the Japanese Center for the Validation of Alternative Methods (JaCVAM) to undertake a catch-up validation study that would compare the revised assay with similar in vitro skin irritation assays, per OECD TG No. 439 (2010). The catch-up validation and supplementary studies for LabCyte EPI-MODEL24 SIT using the revised SOPs were conducted at three laboratories. These results showed that the revised SOP of LabCyte EPI-MODEL24 SIT conformed more accurately to the classifications for skin irritation under the United Nations Globally Harmonised System of Classification and Labelling of Chemicals (UN GHS), thereby highlighting the importance of an optimized rinsing operation for the removal of exposed chemicals in obtaining consistent results from in vitro skin irritation assays. PMID:24122860

  16. Skin Substitutes

    PubMed Central

    Howe, Nicole; Cohen, George

    2014-01-01

    In a relatively short timespan, a wealth of new skin substitutes made of synthetic and biologically derived materials have arisen for the purpose of wound healing of various etiologies. This review article focuses on providing an overview of skin substitutes including their indications, contraindications, benefits, and limitations. The result of this overview was an appreciation of the vast array of options available for clinicians, many of which did not exist a short time ago. Yet, despite the rapid expansion this field has undergone, no ideal skin substitute is currently available. More research in the field of skin substitutes and wound healing is required not only for the development of new products made of increasingly complex biomolecular material, but also to compare the existing skin substitutes. PMID:25371771

  17. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis

    SciTech Connect

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  18. Sink or swim: a test of tadpole behavioral responses to predator cues and potential alarm pheromones from skin secretions.

    PubMed

    Maag, Nino; Gehrer, Lukas; Woodhams, Douglas C

    2012-11-01

    Chemical signaling is a vital mode of communication for most organisms, including larval amphibians. However, few studies have determined the identity or source of chemical compounds signaling amphibian defensive behaviors, in particular, whether alarm pheromones can be actively secreted from tadpoles signaling danger to conspecifics. Here we exposed tadpoles of the common toad Bufo bufo and common frog Rana temporaria to known cues signaling predation risk and to potential alarm pheromones. In both species, an immediate reduction in swimming activity extending over an hour was caused by chemical cues from the predator Aeshna cyanea (dragonfly larvae) that had been feeding on conspecific tadpoles. However, B. bufo tadpoles did not detectably alter their behavior upon exposure to potential alarm pheromones, neither to their own skin secretions, nor to the abundant predator-defense peptide bradykinin. Thus, chemicals signaling active predation had a stronger effect than general alarm secretions of other common toad tadpoles. This species may invest in a defensive strategy alternative to communication by alarm pheromones, given that Bufonidae are toxic to some predators and not known to produce defensive skin peptides. Comparative behavioral physiology of amphibian alarm responses may elucidate functional trade-offs in pheromone production and the evolution of chemical communication. PMID:22972229

  19. PMP22 messenger RNA levels in skin biopsies: testing the effectiveness of a Charcot-Marie-Tooth 1A biomarker.

    PubMed

    Nobbio, Lucilla; Visigalli, Davide; Radice, Davide; Fiorina, Elisabetta; Solari, Alessandra; Lauria, Giuseppe; Reilly, Mary M; Santoro, Lucio; Schenone, Angelo; Pareyson, Davide

    2014-06-01

    Charcot-Marie-Tooth disease type 1A (CMT1A) is associated with increased gene dosage for PMP22. Therapeutic approaches are currently aiming at correcting PMP22 over-expression. It is unknown whether PMP22 can be used as a biological marker of disease progression and therapy efficacy. We performed quantitative real-time polymerase chain reaction on skin biopsies of 45 patients with CMT1A, obtained at study entry and after 24-months of treatment either with ascorbic acid or placebo. Data of a subgroup of patients were also compared with matched healthy subjects. Finally, we analysed PMP22 messenger RNA levels in sural nerve biopsies. We did not find significant differences in the levels of any known PMP22 transcripts in treated or untreated patients with CMT1A, thus confirming that ascorbic acid does not impact on the molecular features of CMT1A. Most importantly, we did not observe any correlation between PMP22 messenger RNA levels and the different clinical and electrophysiological outcome measures, underscoring the weakness of PMP22 to mirror the phenotypic variability of patients with CMT1A. We did not find increased PMP22 messenger RNA levels in skin and sural nerve biopsies of patients with CMT1A compared with relative controls. In conclusion, this study shows that ascorbic acid does not impact on PMP22 transcriptional regulation and PMP22 is not a suitable biomarker for CMT1A. PMID:24812204

  20. A test of geochemical reactivity as a function of mineral size: Manganese oxidation promoted by hematite nanoparticles

    NASA Astrophysics Data System (ADS)

    Madden, Andrew S.; Hochella, Michael F.

    2005-01-01

    Mn 2+(aq) oxidation as promoted by hematite in the presence of molecular oxygen has been studied as a function of hematite particle size. This system is a good candidate to serve as a test of the change of particle reactivity as a function of size due not only to its importance in Earth/environmental processes, but also because it involves electronic coupling between the hematite and adsorbed manganese. The properties of nanoscale hematite, including size quantization of the electronic structure and the relative proportions of terrace vs. edge/kink sites, are expected to change significantly with the particle size in this size range. Experimental results from this study suggest that the heterogeneous manganese oxidation rate is approximately one to one and a half orders of magnitude greater on hematite particles with an average diameter of 7.3 nm than with those having an average diameter of 37 nm, even when normalized to the surface areas of the particles. The acceleration of electron transfer rate for the reactions promoted by the smallest particles is rationalized in the framework of electron transfer theory. According to this theory, for a reaction such as heterogeneous Mn oxidation, the rate depends on three factors: the electronic coupling between initial and final electronic states, the substantial reorganization energy for solvent and coordinated ligands between initial and final states, and the free energy of reaction (corrected for work required to bring reactants together). The adsorbed Mn is electronically coupled with the solid during the electron transfer, and changes in the electronic structure of the solid would be expected to influence the rate. The Lewis base character of surface oxygen atoms increases as the electronic structure becomes quantized, which should allow increased coupling with adsorbed Mn. Finally, as demonstrated previously by in situ AFM observations, the reaction proceeds most readily at topographic features that distort the

  1. Skin Cancer in Skin of Color

    PubMed Central

    Bradford, Porcia T.

    2009-01-01

    Skin cancers in skin of color often present atypically or with advanced stage in comparison to Caucasian patients. Health care providers must maintain a high index of suspicion when examining skin lesions in skin of color. PMID:19691228

  2. Modeling and testing of reactive contaminant transport in drinking water pipes: chlorine response and implications for online contaminant detection.

    PubMed

    Jeffrey Yang, Y; Goodrich, James A; Clark, Robert M; Li, Sylvana Y

    2008-03-01

    A modified one-dimensional Danckwerts convection-dispersion-reaction (CDR) model is numerically simulated to explain the observed chlorine residual loss for a "slug" of reactive contaminants instantaneously introduced into a drinking water pipe of assumed no or negligible wall demand. In response to longitudinal dispersion, a contaminant propagates into the bulk phase where it reacts with disinfectants in the water. This process generates a U-shaped pattern of chlorine residual loss in a time-series concentration plot. Numerical modeling indicates that the residual loss curve geometry (i.e., slope, depth, and width) is a function of several variables such as axial Péclet number, reaction rate constants, molar fraction of the fast- and slow-reacting contaminants, and the quasi-steady-state chlorine decay inside the "slug" which serves as a boundary condition of the CDR model. Longitudinal dispersion becomes dominant for less reactive contaminants. Pilot-scale pipe flow experiments for a non-reactive sodium fluoride tracer and the fast-reacting aldicarb, a pesticide, were conducted under turbulent flow conditions (Re=9020 and 25,000). Both the experimental results and the CDR modeling are in agreement showing a close relationship among the aldicarb contaminant "slug", chlorine residual loss and its variations, and a concentration increase of chloride as the final reaction product. Based on these findings, the residual loss curve and its geometry are useful tools to identify the presence of a contaminant "slug" and infer its reactive properties in adaptive contaminant detections. PMID:17991507

  3. Ballistic skin simulant.

    PubMed

    Jussila, Jorma; Leppäniemi, Ari; Paronen, Mikael; Kulomäki, Erkki

    2005-05-28

    Hydrogels prepared from water solutions containing 10-20 mass% gelatine are generally accepted muscle tissue simulants in terminal ballistic research. They, however, do not have a surface layer which simulates the effect of human skin. The purpose of this research was to find a suitable skin simulant for enhancing the testing fidelity and the credibility of the results with gelatine-based materials when assessing the injury potential of not only high energy bullets, but also especially that of non-penetrating "less lethal" kinetic impact ammunition and relatively low energy ricochet fragments. A skin simulant also permits the simulation and assessment of exit wounds. The mechanical and ballistic properties of human skin and target simulant were established on the basis of results found in the literature. Some errors in these were found. The corrected values are included in this paper for comparison. The target values of the mechanical properties of the skin simulant were the following: threshold velocity v(th)=94+/-4 m/s, tensile strength 18+/-2 N/mm2 and elongation at break 65+/-5%. A selection of synthetic and natural materials was evaluated as skin simulants by analysing their mechanical and ballistic properties. The results were compared to literature values obtained with human cadavers. The tests showed that the best skin simulant of the ones evaluated was semi-finished chrome tanned upholstery "crust" cowhide of 0.9-1.1 mm nominal thickness. Its threshold velocity was 90.7 m/s, tensile strength 20.89+/-4.11 MPa and elongation at break 61+/-9%. These values are the same as the average values of human skin. Of the synthetic materials evaluated, 1mm thick natural rubber can be used on impact side as a threshold velocity filter with some reservations although its theoretical threshold velocity is only 82.9 m/s. PMID:15837009

  4. Hyperelastic skin

    MedlinePlus

    ... is most often seen in people who have Ehlers-Danlos syndrome. People with this disorder have very elastic skin. ... any member of your family been diagnosed with Ehlers-Danlos syndrome? What other symptoms are present?

  5. Your Skin

    MedlinePlus

    ... Butterflies? Read This Chloe & Nurb Meet The Brain (Movie) Quiz: Do You Need a Flu Shot? Got ... For Kids For Parents MORE ON THIS TOPIC Movie: Skin Acne Myths Blisters, Calluses, and Corns Fungal ...

  6. Skin Cancer

    MedlinePlus

    ... Review. 17 Wu S, Han J, Laden F, Qureshi AA. Long-term ultraviolet flux, other potential risk factors, ... MR, Shive ML, Chren MM, Han J, Qureshi AA, Linos E. Indoor tanning and non-melanoma skin ...

  7. Skin Infections

    MedlinePlus

    ... nearby What to Do Teach kids not to pop, pick at, or scratch pimples, pus-filled infections, ... Your Skin Abscess Impetigo Ringworm Cellulitis Should I Pop My Pimple? Tips for Taking Care of Your ...

  8. Skin Cancer

    MedlinePlus

    ... exposure to ultraviolet light, which is found in sunlight and in lights used in tanning salons. What ... the safe-sun guidelines. 1. Avoid the sun. Sunlight damages your skin. The sun is strongest during ...

  9. Skin Cancer

    MedlinePlus

    ... early. If not treated, some types of skin cancer cells can spread to other tissues and organs. Treatments ... and a type of laser light to kill cancer cells. Biologic therapy boosts your body's own ability to ...

  10. Hyperelastic skin

    MedlinePlus

    ... is most often seen in people who have Ehlers-Danlos syndrome. People with this disorder have very elastic skin. ... any member of your family been diagnosed with Ehlers-Danlos syndrome? What other symptoms are present? Alternative Names India ...

  11. Skin Cancer

    MedlinePlus

    ... States. The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, ... If not treated, some types of skin cancer cells can spread to other tissues and organs. Treatments ...

  12. [Prevalence of infection with Mycobacterium tuberculosis and associated factors in community health workers in Brazil based on the tuberculin skin test].

    PubMed

    Rogerio, Wesley Pereira; Prado, Thiago Nascimento do; Souza, Fernanda Mattos de; Pinheiro, Jair dos Santos; Rodrigues, Patrícia Marques; Sant'anna, Amanda Pissinate do Nascimento; Jesus, Kássia Gomes de; Cerutti Junior, Crispim; Lima, Rita de Cássia Duarte; Maciel, Ethel Leonor Noia

    2015-10-01

    This article aimed to determine the prevalence of latent Mycobacterium tuberculosis infection and associated factors in community health workers (CHW) in Brazil, using two cutoff points for the tuberculin skin test (5mm and 10mm). This was a cross-sectional study with data on gender, age, BCG scar, working in a primary care unit (PCU), having a household contact with tuberculosis (TB), alcohol consumption, previous tuberculin skin test (TST), smoking, time on the job as CHW, and comorbidities. Logistic regression was used to estimate odds ratios (OR) and to control for confounding. TST was applied and read after 48-72 hours. Prevalence rates were 57.88% and 37.3%, respectively, for the 5mm and 10mm TST cutoffs. Variables that remained associated with positive TST using the 10mm cutoff were working in a primary care unit that had implemented a Tuberculosis Control Program (TCP) and history of household contact with TB. Variables associated with the 5mm cutoff were working in a primary care unit with a TCP. Necessary actions at the local level include awareness-raising and strengthening of continuing education. PMID:26735386

  13. Senescent Skin

    PubMed Central

    Kushniruk, William

    1974-01-01

    The cutaneous surface is continually influenced by aging and environmental factors. A longer life span is accompanied by an increase in the frequency of problems associated with aging skin. Although most of these changes and lesions are not life threatening, the premalignant lesions must be recognized and treated. The common aging and actinic skin changes are discussed and appropriate management is described. ImagesFig. 1Fig. 2Fig. 3Fig. 4 PMID:20469067

  14. Neuromodulators for Aging Skin

    MedlinePlus

    ... Non-ablative Laser Rejuvenation Non-invasive Body Contouring Treatments Skin Cancer Skin Cancer Information Free Skin Cancer Screenings Skin ... Non-ablative Laser Rejuvenation Non-invasive Body Contouring Treatments Skin Cancer Skin Cancer Information Free Skin Cancer Screenings Skin ...

  15. Skin care and incontinence

    MedlinePlus

    Incontinence - skin care ... in a wheelchair, regular chair, or bed TAKING CARE OF THE SKIN Using diapers and other products ... skin. Over time, the skin breaks down. Special care must be taken to keep the skin clean ...

  16. Skin characteristics in newborns

    MedlinePlus

    Newborn skin characteristics; Infant skin characteristics ... the first few weeks of the baby's life. Newborn skin will vary, depending on the length of the pregnancy. Premature infants have thin, transparent skin. The skin of a ...

  17. The relation of autologous serum and plasma skin test results with urticarial activity score, sex and age in patients with chronic urticaria

    PubMed Central

    Aktar, Sirac; Akdeniz, Necmettin; Calka, Omer; Karadag, Ayse Serap

    2015-01-01

    Introduction Some previous studies reported autoimmunity as an etiologic factor in chronic urticaria (CU), but the results of some autoimmunity tests in these studies are conflicting. Aim To concretize whether there was any relation of autologous serum skin test (ASST) and autologous plasma skin test (APST) results with sex, age and urticarial activity score (UAS) in patients with CU. Material and methods Fifty patients with CU and twenty healthy subjects admitted to our dermatology clinic were included in the present study. The ASST and APST were applied to all individuals. Results The positiveness rates of ASST and APST were significantly higher in the patient group than controls (p = 0.027, p = 0.001, respectively). Among patients, the APST positiveness rate (72%) was significantly (p < 0.05) higher than ASST (46%). It was seen that 48% of patients with negative ASST results had positive APST. However, no patient with negative APST results had positive ASST. There were significant (p < 0.05) relations of the tests’ positiveness rates with sex and old age but with UAS. The diameter of the erythematous papule was remarkably (p < 0.05) larger in APST than ASST and also significantly (p < 0.05) larger in females compared to males in both tests (p < 0.05). It was positively increased with old age (p < 0.05). Conclusions We can suggest that APST is more sensitive than ASST in the assessment of autoimmunity in CU. A high positiveness rate of APST results may be attributed to high numbers of autoantibodies and coagulation factors present in plasma that might probably play a role in etiopathogenesis of CU. PMID:26161057

  18. Pregnancy and Skin

    PubMed Central

    Vora, Rita V.; Gupta, Rajat; Mehta, Malay J.; Chaudhari, Arvind H.; Pilani, Abhishek P.; Patel, Nidhi

    2014-01-01

    Pregnancy is associated with complex of endocrinological, immunological, metabolic, and vascular changes that may influence the skin and other organs in various ways. Pregnancy is a period in which more than 90% women have significant and complex skin changes that may have great impact on the woman's life. The dermatoses of pregnancy represent a heterogeneous group of skin diseases related to pregnancy and/or the postpartum period. The dermatoses of pregnancy can be classified into the following three groups: Physiologic skin changes in pregnancy, pre-existing dermatoses affected by pregnancy, and specific dermatoses of pregnancy. Though most of these skin dermatoses are benign and resolve in postpartum period, a few can risk fetal life and require antenatal surveillance. Most of the dermatoses of pregnancy can be treated conservatively but a few require intervention in the form of termination of pregnancy. Correct diagnosis is essential for the treatment of these disorders. This article discusses the current knowledge of various skin changes during pregnancy and the evaluation of the patient with pregnancy dermatoses with special emphasis on clinical features, diagnostic tests, maternal and fetal prognosis, therapy, and management. PMID:25657937

  19. When memory leads the brain to take scenes at face value: face areas are reactivated at test by scenes that were paired with faces at study.

    PubMed

    Walker, John A; Low, Kathy A; Cohen, Neal J; Fabiani, Monica; Gratton, Gabriele

    2014-01-01

    In the first use of the event-related optical signal as a brain imaging tool for the study of long-term memory, we examined relational or associative aspects of memory, widely presumed to involve the interplay among multiple brain regions in representing and reactivating different elements of a given event. Here, we found that a brain region known to be involved in face processing (the posterior superior temporal sulcus) was active not only when viewing faces during the study phase but also when viewing scenes at test that, through prior learning, were associated with specific faces. These findings, demonstrating the activation of stimulus-specific cortical regions in the absence of stimuli of that type, based on learned relations, reveal cortical substrates of the reactivation of relational memories. PMID:24523688

  20. Identification of Helicobacter pylori in skin biopsy of prurigo pigmentosa.

    PubMed

    Missall, Tricia A; Pruden, Samuel; Nelson, Christine; Fohn, Laurel; Vidal, Claudia I; Hurley, M Yadira

    2012-06-01

    A 23-year-old Chinese man presented with a 3-year history of a pruritic eruption. On examination, pink urticarial papules associated with hyperpigmented reticulated patches were noted on his neck, back, and upper chest. Histopathology revealed vacuolar interface dermatitis and numerous gram-negative rods within a dilated hair follicle. The organisms were reactive with anti-Helicobacter pylori immunohistochemisty. The histologic findings and clinical presentation support the diagnosis of prurigo pigmentosa. Additional testing demonstrated a positive urease breath test and serum H. pylori IgG antibodies. The patient was referred to gastroenterology and treated with appropriate antibiotics. After treatment, esophagogastroduodenoscopy revealed chronic gastritis without evidence of H. pylori infection and his skin showed reticulated hyperpigmented patches without evidence of active inflammatory papules. Although previous reports have associated prurigo pigmentosa to H. Pylori gastritis, this is the first report of H. pylori organisms identified in a skin biopsy of prurigo pigmentosa. PMID:22197863

  1. Consensus of classification trees for skin sensitisation hazard prediction.

    PubMed

    Asturiol, D; Casati, S; Worth, A

    2016-10-01

    Since March 2013, it is no longer possible to market in the European Union (EU) cosmetics containing new ingredients tested on animals. Although several in silico alternatives are available and achievements have been made in the development and regulatory adoption of skin sensitisation non-animal tests, there is not yet a generally accepted approach for skin sensitisation assessment that would fully substitute the need for animal testing. The aim of this work was to build a defined approach (i.e. a predictive model based on readouts from various information sources that uses a fixed procedure for generating a prediction) for skin sensitisation hazard prediction (sensitiser/non-sensitiser) using Local Lymph Node Assay (LLNA) results as reference classifications. To derive the model, we built a dataset with high quality data from in chemico (DPRA) and in vitro (KeratinoSens™ and h-CLAT) methods, and it was complemented with predictions from several software packages. The modelling exercise showed that skin sensitisation hazard was better predicted by classification trees based on in silico predictions. The defined approach consists of a consensus of two classification trees that are based on descriptors that account for protein reactivity and structural features. The model showed an accuracy of 0.93, sensitivity of 0.98, and specificity of 0.85 for 269 chemicals. In addition, the defined approach provides a measure of confidence associated to the prediction. PMID:27458072

  2. Integrated Computational Solution for Predicting Skin Sensitization Potential of Molecules

    PubMed Central

    Desai, Aarti; Singh, Vivek K.; Jere, Abhay

    2016-01-01

    Introduction Skin sensitization forms a major toxicological endpoint for dermatology and cosmetic products. Recent ban on animal testing for cosmetics demands for alternative methods. We developed an integrated computational solution (SkinSense) that offers a robust solution and addresses the limitations of existing computational tools i.e. high false positive rate and/or limited coverage. Results The key components of our solution include: QSAR models selected from a combinatorial set, similarity information and literature-derived sub-structure patterns of known skin protein reactive groups. Its prediction performance on a challenge set of molecules showed accuracy = 75.32%, CCR = 74.36%, sensitivity = 70.00% and specificity = 78.72%, which is better than several existing tools including VEGA (accuracy = 45.00% and CCR = 54.17% with ‘High’ reliability scoring), DEREK (accuracy = 72.73% and CCR = 71.44%) and TOPKAT (accuracy = 60.00% and CCR = 61.67%). Although, TIMES-SS showed higher predictive power (accuracy = 90.00% and CCR = 92.86%), the coverage was very low (only 10 out of 77 molecules were predicted reliably). Conclusions Owing to improved prediction performance and coverage, our solution can serve as a useful expert system towards Integrated Approaches to Testing and Assessment for skin sensitization. It would be invaluable to cosmetic/ dermatology industry for pre-screening their molecules, and reducing time, cost and animal testing. PMID:27271321

  3. Increased matriptase zymogen activation in inflammatory skin disorders

    PubMed Central

    Chen, Cheng-Jueng; Wu, Bai-Yao; Tsao, Pai-In; Chen, Chi-Yung; Wu, Mei-Hsuan; Chan, Yee Lam E.; Lee, Herng-Sheng; Johnson, Michael D.; Eckert, Richard L.; Chen, Ya-Wen; Chou, Fengpai; Lin, Chen-Yong

    2011-01-01

    Matriptase, a type 2 transmembrane serine protease, and its inhibitor hepatocyte growth factor activator inhibitor (HAI)-1 are required for normal epidermal barrier function, and matriptase activity is tightly regulated during this process. We therefore hypothesized that this protease system might be deregulated in skin disease. To test this, we examined the level and activation state of matriptase in examples of 23 human skin disorders. We first examined matriptase and HAI-1 protein distribution in normal epidermis. Matriptase was detected at high levels at cell-cell junctions in the basal layer and spinous layers but was present at minimal levels in the granular layer. HAI-1 was distributed in a similar pattern, except that high-level expression was retained in the granular layer. This pattern of expression was retained in most skin disorders. We next examined the distribution of activated matriptase. Although activated matriptase is not detected in normal epidermis, a dramatic increase is seen in keratinocytes at the site of inflammation in 16 different skin diseases. To gain further evidence that activation is associated with inflammatory stimuli, we challenged HaCaT cells with acidic pH or H2O2 and observed matriptase activation. These findings suggest that inflammation-associated reactive oxygen species and tissue acidity may enhance matriptase activation in some skin diseases. PMID:21123732

  4. Testing a social cognitive theory-based model of indoor tanning: implications for skin cancer prevention messages.

    PubMed

    Noar, Seth M; Myrick, Jessica Gall; Zeitany, Alexandra; Kelley, Dannielle; Morales-Pico, Brenda; Thomas, Nancy E

    2015-01-01

    The lack of a theory-based understanding of indoor tanning is a major impediment to the development of effective messages to prevent or reduce this behavior. This study applied the Comprehensive Indoor Tanning Expectations (CITE) scale in an analysis of indoor tanning behavior among sorority women (total N = 775). Confirmatory factor analyses indicated that CITE positive and negative expectations were robust, multidimensional factors and that a hierarchical structure fit the data well. Social cognitive theory-based structural equation models demonstrated that appearance-oriented variables were significantly associated with outcome expectations. Outcome expectations were, in turn, significantly associated with temptations to tan, intention to tan indoors, and indoor tanning behavior. The implications of these findings for the development of messages to prevent and reduce indoor tanning behavior are discussed in two domains: (a) messages that attempt to change broader societal perceptions about tan skin, and (b) messages that focus more narrowly on indoor tanning-challenging positive expectations, enhancing negative expectations, and encouraging substitution of sunless tanning products. PMID:25470441

  5. Clinical performance of the Multispot HIV-1/HIV-2 rapid test to correctly differentiate HIV-2 from HIV-1 infection in screening algorithms using third and fourth generation assays and to identify cross reactivity with the HIV-1 Western Blot

    PubMed Central

    Ramos, Eric M.; Harb, Socorro; Dragavon, Joan; Coombs, Robert W.

    2014-01-01

    Background An accurate and rapid serologic method to differentiate HIV-2 from HIV-1 infection is required since the confirmatory HIV-1 Western Blot (WB) may demonstrate cross-reactivity with HIV-2 antibodies. Objectives To evaluate the performance of the Bio-Rad Multispot HIV-1/HIV-2 rapid assay as a supplemental test to correctly identify HIV-2 infection and identify HIV-1 WB cross-reactivity with HIV-2 in clinical samples tested at an academic medical center. Study design Between August 2008 and July 2012, clinical samples were screened for HIV using either 3rd-or 4th-generation HIV-1/2 antibody or combination antibody and HIV-1 p24 antigen assays, respectively. All repeatedly reactive samples were reflexed for Multispot rapid testing. Multispot HIV-2 and HIV-1 and HIV-2-reactive samples were further tested using an HIV-2 immunoblot assay and HIV-1 or HIV-2 RNA assays when possible. The HIV-1 WB was performed routinely for additional confirmation and to assess for HIV-2 antibody cross-reactivity. Results Of 46,061 samples screened, 890 (89.6%) of 993 repeatedly reactive samples were also Multispot-reactive: 882 for HIV-1; three for only HIV-2; and five for both HIV-1 and HIV-2. All three HIV-2-only Multispot-positives along with a single dually reactive HIV-1/2 Multispot-positive were also HIV-2 immunoblot-positive; the latter was HIV-1 RNA negative and HIV-2 RNA positive. Conclusions The Multispot rapid test performed well as a supplemental test for HIV-1/2 diagnostic testing. Four new HIV-2 infections (0.45%) were identified from among 890 Multispot-reactive tests. The use of HIV-1 WB alone to confirm HIV-1/2 screening assays may underestimate the true prevalence of HIV-2 infection in the United States. PMID:24342468

  6. Reactivity to nicotine cues over repeated cue reactivity sessions.

    PubMed

    LaRowe, Steven D; Saladin, Michael E; Carpenter, Matthew J; Upadhyaya, Himanshu P

    2007-12-01

    The present study investigated whether reactivity to nicotine-related cues would attenuate across four experimental sessions held 1 week apart. Participants were nineteen non-treatment seeking, nicotine-dependent males. Cue reactivity sessions were performed in an outpatient research center using in vivo cues consisting of standardized smoking-related paraphernalia (e.g., cigarettes) and neutral comparison paraphernalia (e.g., pencils). Craving ratings were collected before and after both cue presentations while physiological measures (heart rate, skin conductance) were collected before and during the cue presentations. Although craving levels decreased across sessions, smoking-related cues consistently evoked significantly greater increases in craving relative to neutral cues over all four experimental sessions. Skin conductance was higher in response to smoking cues, though this effect was not as robust as that observed for craving. Results suggest that, under the described experimental parameters, craving can be reliably elicited over repeated cue reactivity sessions. PMID:17537583

  7. An In Vitro HSV-1 Reactivation Model Containing Quiescently Infected PC12 Cells

    PubMed Central

    Hogk, Ina; Kaufmann, Michaela; Finkelmeier, Doris; Rupp, Steffen

    2013-01-01

    Abstract Advances in the understanding of the infection and reactivation process of herpes simplex type 1 (HSV-1) are generally gained by monolayer cultures or extensive and cost-intensive animal models. So far, no reliable in vitro skin model exists either to investigate the molecular mechanisms involved in controlling latency and virus reactivation or to test pharmaceuticals. Here we demonstrate the first in vitro HSV-1 reactivation model generated by using the human keratinocyte cell line HaCaT grown on a collagen substrate containing primary human fibroblasts. We integrated the unique feature of a quiescently infected neuronal cell line, the rat pheochromocytoma line PC12, within the dermal layer of the three-dimensional skin equivalent. Transmission electron microscopy, a cell-based TCID50 assay, and polymerase chain reaction analysis were used to verify cell latency. Thereby viral DNA could be detected, whereas extracellular as well as intracellular virus activity could not be found. Further, the infected PC12 cells show no spontaneous reactivation within the in vitro skin equivalent. In order to simulate a physiologically comparable HSV-1 infection, we achieved a specific and pointed reactivation of quiescently HSV-1 infected PC12 cells by UVB irradiation at 1000 mJ/cm2. PMID:23914331

  8. The evolution of food immune reactivity testing: why immunoglobulin G or immunoglobulin A antibody for food may not be reproducible from one lab to another.

    PubMed

    Vojdani, Aristo

    2015-01-01

    The gold standard for identifying food reactions is the elimination-provocation diet. Embarking on this long, tedious journey takes an expert practitioner and a completely dedicated patient, with a whole lot of patience from both. In the contemporary fast lane, microwave, "give me a pill" popping, I-want-satisfaction-now society, many clinicians have turned to laboratory assessments for quick answers to food reactivity. From the introduction of cytotoxic testing for food allergies in 1947 until today, food reactivity testing has evolved and branched; it has been both pseudoimproved and scientifically improved. With multiple available options for methodology, specimen types, and clinical lab, how is a clinician expected to find the one that fits the requirements of a particular practice? How, indeed, when one self-promoting paper supports a particular methodology, while another criticizes it? In this article, with the benefit of his years of training and experience as a research scientist and test development expert, the author, who is trained in both microbiology and immunology, discusses the history of food testing, analyzes the criticisms of it, reviews the scientific literature, and tours the methodologies. PMID:25599182

  9. An evaluation of factors associated with taking and responding positive to the tuberculin skin test in individuals with HIV/AIDS

    PubMed Central

    2011-01-01

    Background The tuberculin skin test (TST) is still the standard test for detecting latent infection by M tuberculosis (LTBI). Given that the Brazilian Health Ministry recommends that the treatment of latent tuberculosis (LTBI) should be guided by the TST results, the present study sets out to describe the coverage of administering the TST in people living with HIV at two referral health centers in the city of Recife, where TST is offered to all patients. In addition, factors associated with the non-application of the test and with positive TST results were also analyzed. Methods A cross-sectional study was carried out with HIV patients, aged 18 years or over, attending outpatient clinics at the Correia Picanço Hospital/SES/PE and the Oswaldo Cruz/UPE University Hospital, who had been recommended to take the TST, in the period between November 2007 and February 2010. Univariate and multivariate logistic regression analyses were carried out to establish associations between the dependent variable - taking the TST (yes/no), at a first stage analysis, and the independent variables, followed by a second stage analysis considering a positive TST as the dependent variable. The odds ratio was calculated as the measure of association and the confidence interval (CI) at 95% as the measure of accuracy of the estimate. Results Of the 2,290 patients recruited, 1087 (47.5%) took the TST. Of the 1,087 patients who took the tuberculin skin test, the prevalence of TST ≥ 5 mm was 21.6% among patients with CD4 ≥ 200 and 9.49% among those with CD4 < 200 (p = 0.002). The patients most likely not to take the test were: men, people aged under 39 years, people with low educational levels and crack users. The risk for not taking the TST was statiscally different for health service. Patients who presented better immunity (CD4 ≥ 200) were more than two and a half times more likely to test positive that those with higher levels of immunodeficiency (CD4 < 200). Conclusions Considering

  10. Physiological reactivity to responsive and unresponsive children as moderated by perceived control.

    PubMed

    Bugental, D B; Cortez, V L

    1988-06-01

    80 undergraduate women, pretested on the Parent Attribution Test (PAT), watched videotapes of responsive and unresponsive children in anticipation of subsequent interaction with them. Physiological measures (heart rate, skin temperature, and skin conductance) were monitored as subjects viewed videotapes and during a postinterview. Subjects who perceived caregiving failure as uncontrollable (on the PAT) were significantly more reactive to variations in child responsiveness than were those who perceived failure as controllable. The highest level of arousal (elevated heart rate and skin conductance) was manifested by "low-control" women anticipating interaction with unresponsive children. The increased arousal level shown in reaction to unresponsive children was accompanied by decreased skin temperature--suggesting the presence of fear or anxiety. Results were interpreted as indicating the importance of social cognitions as moderators of caregiver response to child behavior. PMID:3383677

  11. Sensitivity and specificity of the consumer open skin allergy test as a method of prediction of contact dermatitis to hair dyes.

    PubMed

    Krasteva, Maya; Cottin, Martin; Cristaudo, Antonio; Lainé, Gérard; Nohynek, Gerhard; Orton, David; Toutain, Hervé; Severino, Vincenzo; Wilkinson, John

    2005-01-01

    To prevent contact dermatitis to oxidative hair colouring products, a consumer test (skin allergy test, SAT) consisting of the open application of the colourant base prior to mixing with the developer is recommended 48 hours before hair colouring. We investigated the sensitivity and specificity of the SAT to detect and prevent contact allergy to oxidative hair colouring products that contained a range of concentrations of para-phenylenediamine (PPD) and corresponded to different shades (light, medium and dark). Test colouring products containing increasing concentrations of PPD (0.1, 0.5, 1.0 or 1.5%) were applied to 34 PPD-positive hair dye-allergic individuals and to 49 non-allergic control subjects. Allergic reactions were elicited in all PPD-positive subjects whereas none occurred in control PPD-negative subjects. For each subject the eliciting concentration of PPD in the SAT was compared with the PPD concentration range of the group of commercial shades reported as causing reactions by the consumer. In all PPD-positive subjects the eliciting concentrations of PPD in the SAT was within or lower than the range of PPD concentrations in the reported eliciting colourant base of commercial products. In conclusion, our results confirm the excellent predictive value of the SAT over the entire range of PPD concentrations used in oxidative hair colouring products and suggest that the test is a suitable tool for the secondary prevention of contact allergic reactions to hair colouring products. PMID:15701588

  12. Skin cancer and photoaging in ethnic skin.

    PubMed

    Halder, Rebat M; Ara, Collette J

    2003-10-01

    Skin cancer prevalence in ethnic skin is low. Squamous cell carcinoma, hypopigmented mycosis fungoides, and acral lentiginous melanoma are the most serious types of skin cancer noted in the darker-skinned population. Photoaging occurs less frequently and is less severe in ethnic skin. PMID:14717413

  13. Discordance of Tuberculin Skin Test and Interferon Gamma Release Assay in Recently Exposed Household Contacts of Pulmonary TB Cases in Brazil

    PubMed Central

    Ribeiro-Rodrigues, Rodrigo; Kim, Soyeon; Coelho da Silva, Flávia Dias; Uzelac, Aleksandra; Collins, Lauren; Palaci, Moíses; Alland, David; Dietze, Reynaldo; Ellner, Jerrold J.; Jones-López, Edward; Salgame, Padmini

    2014-01-01

    Interferon-gamma (IFN-γ) release assays (IGRAs) such as the Quantiferon Gold In-tube test are in vitro assays that measure IFN-γ release from T cells in response to M. tuberculosis (Mtb)-specific antigens. Unlike the tuberculin