Science.gov

Sample records for skin test reactivity

  1. Allergy history does not predict skin test reactivity in asthmatic children.

    PubMed

    Carter, E R; Pulos, E; Delaney, J; Matheson, E J; Moffitt, D R

    2000-12-01

    We prospectively assessed how well patient report of allergy to cat, dust mite, and grass predicted the results of skin prick testing to those allergens in 95 asthmatic children. Children between 4 and 18 years old with physician-documented asthma provided a detailed standardized allergy history and then underwent skin prick testing. The children were categorized by asthma severity. The diagnostic accuracy, which was the primary outcome measure, as well as sensitivity, specificity, and positive and negative predicted values were calculated for allergy history with regards to skin test reactivity. The diagnostic accuracy of allergy history in identifying skin test reactivity was 65%, 50%, and 56% for cat, dust mite, and grass, respectively. Asthma severity did not affect the diagnostic accuracy. Allergy history was a poor predictor of skin test reactivity in this group of asthmatic children.

  2. Skin test reactivity to female sex hormones in women with primary unexplained recurrent pregnancy loss.

    PubMed

    Ellaithy, Mohamed I; Fathi, Hesham M; Farres, Mohamed N; Taha, Marwa S

    2013-09-01

    The objective was to examine the hypothesis that primary unexplained recurrent pregnancy loss might be associated with an inappropriate immunologically mediated response to progesterone and/or estrogen. This prospective study included 47 women with two or more documented consecutive early pregnancy losses of unknown etiology, and no previous history of deliveries. Intradermal skin testing was performed in the luteal phase of the cycle (days 16-20) using estradiol benzoate, progesterone, and a placebo of refined sesame oil. Immediate (20 min) and late (24h and 1 week) skin test readings for all cases were compared with those of 12 parous women of comparable age with no history of spontaneous miscarriages, premenstrual disorders, pregnancy, or sex hormone-related allergic or autoimmune diseases. Main outcome measure was skin test reactivity to estradiol and/or progesterone. Immediate skin test reactivity to both hormones was observed among half of the cases at 20 min. A papule after 24h, which persisted for up to 1 week, was observed among 32 (68.1%) and 34 (72.3%) cases at the sites of estrogen and progesterone injection, respectively. 55.3% of cases had combined skin test reactivity to both estradiol and progesterone at 1 week. All women in the control group showed absence of skin test reactivity for both estradiol and progesterone at 20 min, 24h, and 1 week. None of the subjects in either group showed skin test reactivity to placebo. There is an association between primary unexplained recurrent pregnancy loss and skin test reactivity to female sex hormones.

  3. Ibrutinib, a BTK inhibitor used for treatment of lymphoproliferative disorders, eliminates both aeroallergen skin test and basophil activation test reactivity.

    PubMed

    Regan, Jennifer A; Cao, Yun; Dispenza, Melanie C; Ma, Shuo; Gordon, Leo I; Petrich, Adam M; Bochner, Bruce S

    2017-04-04

    Ibrutinib, a Bruton's tyrosine kinase (BTK) inhibitor, was shown to eliminate skin test reactivity in vivo and IgE-dependent basophil activation testing ex vivo. Blockade of the BTK pathway may represent a novel therapeutic strategy for the effective reduction of allergic reactivity.

  4. Mold and Alternaria skin test reactivity and asthma in children in Connecticut

    PubMed Central

    Lyons, Todd W.; Wakefield, Dorothy B.; Cloutier, Michelle M.

    2013-01-01

    Background Sensitivity to mold has been associated with asthma incidence, persistence, and severity. Objective To examine the relationship between skin test reactivity (STR) to molds and specifically to Alternaria and asthma severity in a group of ethnically diverse children in Connecticut. Methods Demographics and STR to 14 local allergens, including Alternaria, Penicillium, and mold mix, were obtained for 914 Puerto Rican, African American, and non-Hispanic white children. Results A total of 126 children (14%) had a positive skin test result to mold, and 58 (6%) demonstrated STR to Alternaria. Compared with non-Hispanic white children, there was no difference in the likelihood of being sensitized to Alternaria for Puerto Rican and African American children (odds ratio [OR], 0.7; 95% confidence interval [CI], 0.3–1.5; and OR, 0.9; 95% CI, 0.4–2.2; respectively). In an adjusted analysis, Alternaria STR was associated with severe, persistent asthma (OR, 3.4; 95% CI, 1.2–8.6) but did not predict increasing asthma severity. STR to cat (OR, 2.5; 95% CI, 1.3–4.9) and dog (OR, 2.9; 95% CI, 1.3–6.0) was also associated with severe persistent asthma. Alternaria STR was associated with severe persistent asthma independent of the total number of positive skin test results. Conclusions Mold and Alternaria STR were uncommon among children in Connecticut. Alternaria STR was not associated with increasing asthma severity but was associated with severe, persistent asthma independent of the total number of positive skin test results. There was no association between ethnicity and Alternaria STR. PMID:21457878

  5. Dissociation between skin test reactivity and anti-aeroallergen IgE: Determinants among urban Brazilian children

    PubMed Central

    Veiga, Rafael V.; Ponte, João C. M.; da Cunha, Sérgio S.; Simões, Silvia M.; Cruz, Álvaro A.; Yazdanbakhsh, Maria; Matos, Sheila M.; Silva, Thiago Magalhães; Figueiredo, Camila A.; Rodrigues, Laura C.; Fiaccone, Rosemeire L.; Cooper, Philip J.; Barreto, Maurício L.

    2017-01-01

    Background The dissociation between specific IgE and skin prick test reactivity to aeroallergens, a common finding in populations living in low and middle-income countries, has important implications for the diagnosis and treatment of allergic diseases. Few studies have investigated the determinants of this dissociation. In the present study, we explored potential factors explaining this dissociation in children living in an urban area of Northeast Brazil, focusing in particular on factors associated with poor hygiene. Methods Of 1445 children from low income communities, investigated for risk factors of allergies, we studied 481 with specific IgE antibodies to any of Blomia tropicalis, Dermatophagoides pteronyssinus, Periplaneta americana and Blatella germanica allergens. Data on demographic, environmental and social exposures were collected by questionnaire; serum IgG and stool examinations were done to detect current or past infections with viral, bacterial, protozoan and intestinal helminth pathogens. We measured atopy by skin prick testing (SPT) and specific IgE (sIgE) to aerollergens in serum (by ImmunoCAP). SIgE reactivity to B. tropicalis extract depleted of carbohydrates was measured by an in-house ELISA. Total IgE was measured by in house capture ELISA. SNPs were typed using Illumina Omni 2.5. Results Negative skin prick tests in the presence of specific IgE antibodies were frequent. Factors independently associated with a reduced frequency of positive skin prick tests were large number of siblings, the presence of IgG to herpes simplex virus, Ascaris lumbricoides and Trichuris trichiura infections, living in neighborhoods with infrequent garbage collection, presence of rodents and cats in the household and sIgE reactivity to glycosylated B. tropicalis allergens. Also, SNP on IGHE (rs61737468) was negatively associated with SPT reactivity. Conclusions A variety of factors were found to be associated with decreased frequency of SPT such as unhygienic

  6. 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.

  7. Skin Prick Test Reactivity in Patients with Chronic Eczematous External Otitis

    PubMed Central

    Kazikdas, K. Cagdas; Ozergin Coskun, Zerrin; Demirci, Munir

    2011-01-01

    Objectives To investigate the incidence of skin prick test (SPT) positivity in patients with eczematous external otitis. Methods Forty-six patients with eczematous external otitis and forty-four healthy volunteers were included in the study. All the patients were skin-tested by prick test. Reactions were assessed by the degree of redness and swelling and the size of the wheal produced. Results According to SPT positivity and total immunoglobulin E values, the difference between the study and the control groups was statistically significant (P<0.05). The most common skin reactions were against to mites and grasses in this study. Conclusion Eczematous external otitis is perhaps the most difficult to treat of all forms of external otitis because the provocative agents usually remain undiagnosed. Patients suffering from eczematous external otitis symptoms should be investigated for allergens and be informed for prevention of the causative agents. SPT might be performed in cases of prolonged or treatment-resistant external otitis. PMID:22232711

  8. 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

  9. Skin microvascular reactivity in patients with hypothyroidism.

    PubMed

    Mihor, Ana; Gergar, Maša; Gaberšček, Simona; Lenasi, Helena

    2016-11-04

    Hypothyroidism is associated with impaired vascular function; however, little is known about its impact on microcirculation. We aimed to determine skin microvascular reactivity in hypothyroidism focusing on endothelial function and the sympathetic response. We measured skin laser Doppler (LD) flux (LDF) on the volar forearm and the finger pulp using LD flowmetry in hypothyroid patients (N = 13) and healthy controls (N = 15). Skin microvascular reactivity was assessed by a three-minute occlusion of the brachial artery, inducing postocclusive reactive hyperaemia (PRH), and by a four-minute local cooling of the hand. An electrocardiogram (ECG), digital artery blood pressure and skin temperature at the measuring sites were recorded. Baseline LDF, the digital artery blood pressure and the heart rate were comparable between patients and controls. On the other hand, patients exhibited significantly longer PRH duration, significantly higher blood pressure during cooling (unpaired t-test, p <0.05) and lower, albeit not significant, LDF in the ipsilateral finger pulp during cooling compared to controls. Unexpectedly, the results of the present study point to an increased vasodilator capacity of skin microcirculation and an apparent increase in sympathetic reactivity after local cooling in hypothyroid patients. Hypothyroidism induces subtle changes of some haemodynamic parameters in skin microcirculation implying altered endothelial function and altered sympathetic reactivity.

  10. The prevalence of antibiotic skin test reactivity in a pediatric population.

    PubMed

    Kamboj, Sonia; Yousef, Ejaz; McGeady, Stephen; Hossain, Jobayer

    2011-01-01

    Although adverse drug reactions (ADRs) are not uncommon, true allergic (i.e., immunologic) reactions are infrequent. Estimates are that only 10% of reported "penicillin (PCN)-allergic" patients have true allergic drug reactions. Most studies of PCN-related ADR have been conducted in adult populations and suggest that the majority of adult patients presenting with PCN allergy history can safely receive the drug. The goal of this study was to examine the outcome of provocative drug challenges to antibiotics in a pediatric population and correlate outcomes with predictive factors. Through chart review, we identified 96 pediatric patients with history of an ADR to antibiotics who underwent skin testing (ST) and/or graded challenges to PCN (n = 52), cephalosporins (n = 7), azithromycin (AZT; n = 24), or clindamycin (n = 4). Of these children with an ADR, 87 (90.6%) tolerated provocative drug challenges and 9 (9.4%) were instructed to continue drug avoidance because of positive ST or failed challenge. Eight of the nine patients continued drug avoidance due to positive PCN ST (n = 4) or ADR during drug PCN challenge (n = 4). All AZT and cephalosporin challenges had negative outcomes, and only one patient did not proceed with the clindamycin challenge after a positive ST. True "antibiotic allergy" denoted by positive ST or failed challenge in patients with a history of ADR occurred in <10% of children included in this study, suggesting that without such testing nearly 90% might be treated with alternative antibiotics unnecessarily.

  11. Skin test reactivity to whole body and fecal extracts of American (Periplaneta americana) and German (Blatella germanica) cockroaches in atopic asthmatics.

    PubMed

    Menon, P; Menon, V; Hilman, B; Stankus, R; Lehrer, S B

    1991-12-01

    Forty-six atopic asthmatic subjects aged 3 to 58 years attending the allergy clinic of a university hospital were evaluated for prick skin test reactivity with commercially available extracts of cockroach (CCE) and house dust (HD). Additionally, skin testing was performed with American cockroach whole body (AWBE) and fecal extracts (AFE) as well as German cockroach whole body (GWBE) and fecal extracts (GFE) prepared in our laboratory. Commercial cockroach extract was prepared from American, German, and Oriental cockroach whole bodies. Skin test reactivity to the different extracts were as follows: 83% to HD, 70% to CCE, 70% to AWBE and/or GWBE, 63% to AWBE, 57% to GWBE, 63% to AFE and/or GFE, 52% to AFE, 50% to GFE, 48% to both AWBE and GWBE, and 39% to both AFE and GFE. The subjects with positive skin tests to AWBE and/or GWBE (70%) were the same individuals who showed skin test reactivity to CCE (70%). Subjects from lower income families (less than $10,000) had a significantly higher skin test reactivity to cockroach allergens than those from families with an annual income of $11,000 to $24,000 (P = .04). These results demonstrate the significance of cockroach sensitization in atopic asthmatics, suggest the importance of fecal cockroach allergens, and support earlier observations of shared interspecies allergens between American and German cockroach whole bodies.

  12. PPD skin test

    MedlinePlus

    ... is a method used to diagnose silent (latent) tuberculosis (TB) infection. PPD stands for purified protein derivative. ... skin test; Tuberculin skin test; Mantoux test Images Tuberculosis in the kidney Tuberculosis in the lung Positive ...

  13. Allergy Skin Tests

    MedlinePlus

    ... allergic rhinitis) Allergic asthma Dermatitis (eczema) Food allergies Penicillin allergy Bee venom allergy Latex allergy Skin tests are ... may recommend this test to check for an allergy to insect venom or penicillin. Patch test Patch testing is generally done to ...

  14. 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.

  15. Leishmania Skin Test

    DTIC Science & Technology

    2010-03-01

    Ninhydrin ), SDS-PAGE and non-viability testing . See Table 3 below: Table 3: Drug Substance Specifications Test Method Specification SDS-PAGE...AD_________________ Award Number: DAMD17-00-C-0030 TITLE: Leishmania Skin Test PRINCIPAL INVESTIGATOR: Nielsen, H.S., Jr...TYPE FINAL, PHASE II ADDENDUM 3. DATES COVERED (From - To) 1 APR 2009 - 28 FEB 2010 4. TITLE AND SUBTITLE Leishmania Skin Test 5a

  16. Allergy testing - skin

    MedlinePlus

    ... may order allergy skin tests if you have: Hay fever ( allergic rhinitis ) and asthma symptoms that are not ... team. Related MedlinePlus Health Topics Allergy Food Allergy Hay Fever Browse the Encyclopedia A.D.A.M., Inc. ...

  17. CSD skin test

    MedlinePlus

    ... features on this page, please enable JavaScript. The cat scratch disease (CSD) skin test was once used to help ... Slater LN, Welch DF, Koehler JE. Bartonella, including cat-scratch disease. In: Bennett JE, Dolin R, Blaser MJ, eds. ...

  18. Chemical Reactivity Test (CRT)

    SciTech Connect

    Zaka, F.

    2016-12-13

    The Chemical Reactivity Test (CRT) is used to determine the thermal stability of High Explosives (HEs) and chemical compatibility between (HEs) and alien materials. The CRT is one of the small-scale safety tests performed on HE at the High Explosives Applications Facility (HEAF).

  19. Echo: skin stress test

    NASA Technical Reports Server (NTRS)

    1960-01-01

    Skin Stress Test of the 12-foot satellite built as a prototype of the full-scale Echo satellite. The 12-foot diameter of the sphere was chosen because that was the ceiling height in the Langley model shop. The proposal to build the 12-foot satellite was made in November 1957. - Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, NASA SP-4308, pp. 170-171.

  20. Skin microvascular reactivity in trained adolescents.

    PubMed

    Roche, Denise M; Rowland, T W; Garrard, M; Marwood, S; Unnithan, V B

    2010-04-01

    Whilst endothelial dysfunction is associated with a sedentary lifestyle, enhanced endothelial function has been documented in the skin of trained individuals. The purpose of this study was to investigate whether highly trained adolescent males possess enhanced skin microvascular endothelial function compared to their untrained peers. Seventeen highly and predominantly soccer trained boys (V(O)(2)(peak): 55 +/- 6 mL kg(-1) min(-1)) and nine age- and maturation-matched untrained controls (V(O)(2)(peak): 43 +/- 5 mL kg(-1) min(-1)) aged 13-15 years had skin microvascular endothelial function assessed using laser Doppler flowmetry. Baseline and maximal thermally stimulated skin blood flow (SkBF) responses were higher in forearms of trained subjects compared to untrained participants [baseline SkBF: 11 +/- 4 vs. 9 +/- 3 perfusion units (PU), p < 0.05; SkBF(max): 282 +/- 120 vs. 204 +/- 68 PU, p < 0.05]. Similarly, cutaneous vascular conductance (CVC) during local heating was superior in the forearm skin of trained versus untrained individuals (CVC(max): 3 +/- 1 vs. 2 +/- 1 PU mmHg(-1), p < 0.05). Peak hyperaemia following arterial occlusion and area under the reactive hyperaemia curve were also greater in forearm skin of the trained group (peak hyperaemia: 51 +/- 21 vs. 35 +/- 15 PU, p < 0.05; area under curve: 1596 +/- 739 vs. 962 +/- 796 PUs, p < 0.05). These results suggest that chronic exercise training in adolescents is associated with enhanced microvascular endothelial vasodilation in non-glabrous skin.

  1. 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

  2. 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

  3. Thermal provocation to evaluate microvascular reactivity in human skin.

    PubMed

    Minson, Christopher T

    2010-10-01

    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.

  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. Typical Reactive Armor Safety Tests

    DTIC Science & Technology

    1993-04-02

    way. etc.). c. Penetration measurements into the backup armor of the dynamic or static rounds (i.e., partial or comple e penetration, depth of...ZP Oe) Alberdeen Prc~ving Ground , MD 21005-5059 Aberdeen Proving Ground , HD 21005-5055 as NAVE 0ýu- TLD,%G 57ON5ORNG 16 (VEif N8 9...OPFJPATIONS PROCEDURE AMSTE-RP-702-10 Test Operatiuns Procedure (TOP) 2-2-623 AD No. 2 April 1993 TYPICAL REACTIVE ARMOR SAFETY TESTS Paragraph 1

  6. What happens after the activation of ascaridole? Reactive compounds and their implications for skin sensitization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To replace animal testing and to improve the prediction of skin sensitization, significant attention has been directed to the use of alternative methods. Along with induction of Nrf2 target gene and upregulation of CD86 and C54 markers, the direct peptide reactivity assay (DPRA), the regulatory agen...

  7. Signaling by reactive oxygen and nitrogen species in skin diseases.

    PubMed

    Afanas'ev, Igor B

    2010-06-01

    For many years the formation of reactive oxygen and nitrogen species (ROS) and (RNS) in living organisms has been considered to be dangerous phenomenon due to their damaging action on biomolecules. However, present studies demonstrated another important activity of ROS and RNS: their signaling functions in physiological and pathological processes. In this work we discuss the new data concerning a role of ROS and RNS in many enzymatic/gene cascades causing damaging changes during the development of skin diseases and pathological disorders (skin cancer, the toxic effects of irradiation on the skin, and skin wounding). It has been suggested that the enhancement of ROS formation in tumor cells through the inactivation of mitochondrial MnSOD or the activation of NADPH oxidase leads to apoptosis and might be applied for developing a new cancer therapy. On the other hand ROS overproduction might stimulate malignant transformation of melanoma. Role of ROS signaling is also considered in the damaging action of UVA, UVB, and IRA irradiation on the skin and the processes of wound healing. In the last part of review the possibility of the right choice of antioxidants and free radical scavengers for the treatment of skin disease is discussed.

  8. A strategy for skin irritation testing.

    PubMed

    Robinson, Michael K; Perkins, Mary A

    2002-03-01

    Skin irritation safety testing and risk assessment for new products, and the ingredients they contain, is a critical requirement before market introduction. In the past, much of this skin testing required the use of experimental animals. However, new current best approaches for skin corrosion and skin irritation testing and risk assessment are being defined, obviating the need for animal test methods. Several in vitro skin corrosion test methods have been endorsed after successful validation and are gaining acceptance by regulatory authorities. In vitro test methods for acute, cumulative (repeat exposure), and chronic (prolonged exposure) skin irritation are under development. Though not yet validated, many are being used successfully for testing and risk assessment purposes as documented through an expanding literature. Likewise, a novel acute irritation patch test in human subjects is providing a valid and ethical alternative to animal testing for prediction of chemical skin irritation potential. An array of other human test methods also have been developed and used for the prediction of cumulative/chronic skin irritation and the general skin compatibility of finished products. The development of instrumental methods (e.g., transepidermal water loss, capacitance, and so on) has provided the means for analyzing various biophysical properties of human skin and changes in these properties caused by exposure to irritants. However, these methods do not directly measure skin inflammation. A recently introduced skin surface tape sampling procedure has been shown to detect changes in skin surface cytokine recovery that correlate with inflammatory skin changes associated with chemical irritant exposures or existing dermatitis. It holds promise for more objective quantification of skin irritation events, including subclinical (sensory) irritation, in the future.

  9. 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

  10. Peptide Reactivity of Isothiocyanates – Implications for Skin Allergy

    NASA Astrophysics Data System (ADS)

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

    2016-02-01

    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.

  11. C-Reactive Protein (CRP) Test

    MedlinePlus

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

  12. Reactive molecule species and antioxidative mechanisms in normal skin and skin aging.

    PubMed

    Wölfle, Ute; Seelinger, Günter; Bauer, Georg; Meinke, Martina C; Lademann, Jürgen; Schempp, Christoph M

    2014-01-01

    Reactive oxygen and nitrogen species (ROS/RNS) which may exist as radicals or nonradicals, as well as reactive sulfur species and reactive carbon species, play a major role in aging processes and in carcinogenesis. These reactive molecule species (RMS), often referred to as 'free radicals' or oxidants, are partly by-products of the physiological metabolism. When RMS concentrations exceed a certain threshold, cell compartments and cells are injured and destroyed. Endogenous physiological mechanisms are able to neutralize RMS to some extent, thereby limiting damage. In the skin, however, pollutants and particularly UV irradiation are able to produce additional oxidants which overload the endogenous protection system and cause early aging, debilitation of immune functions, and skin cancer. The application of antioxidants from various sources in skin care products and food supplements is therefore widespread, with increasingly effective formulations being introduced. The harmful effects of RMS (aside from impaired structure and function of DNA, proteins, and lipids) are: interference with specific regulatory mechanisms and signaling pathways in cell metabolism, resulting in chronic inflammation, weakening of immune functions, and degradation of tissue. Important control mechanisms are: MAP-kinases, the aryl-hydrocarbon receptor (AhR), the antagonistic transcription factors nuclear factor-κB and Nrf2 (nuclear factor erythroid 2-related factor 2), and, especially important, the induction of matrix metalloproteinases which degrade dermal connective tissue. Recent research, however, has revealed that RMS and in particular ROS/RNS are apparently also produced by specific enzyme reactions in an evolutionarily adapted manner. They may fulfill important physiologic functions such as the activation of specific signaling chains in the cell metabolism, defense against infectious pathogens, and regulation of the immune system. Normal physiological conditions are characterized by

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Aspergillus antigen skin test (image)

    MedlinePlus

    ... After 48 to 72 hours the site of injection is evaluated by a physician. If a positive reaction occurs (the test site is inflamed), the person has been exposed to the aspergillus mold and is at risk for developing aspergillosis.

  18. Development of reactive topical skin protectants against sulfur mustard and nerve agents.

    PubMed

    Koper, O; Lucas, E; Klabunde, K J

    1999-12-01

    The potential for highly reactive nanoparticles (RNP) to absorb destructively, i.e. to neutralize highly toxic substances such as the warfare agents GA, GB, HD and VX, has been demonstrated in the laboratory. Reactive nanoparticles represent a new class of nanoscale particles of metals and metal oxides that differ from other nanoparticles in reactivity and crystalline morphology. The potential for incorporating RNP into a protective barrier skin cream also has been demonstrated. Preliminary studies indicate that RNP are physically and chemically compatible with a base cream provided by the Army Medical Research Office and, importantly, remain reactive with chemical agents while promising to be compatible with skin contact.

  19. Isolation of glycopeptides with skin test activity from dermatophytes.

    PubMed Central

    Moser, S A; Pollack, J D

    1978-01-01

    By using ethylene glycol extraction of whole submerged cultures followed by Sephadex G-200 and diethylaminoethyl-Sephadex chromatography, we isolated four distinct glycopeptides from Trichophyton mentagrophytes, T. rubrum, and Microsporum canis. Chemical analyses revealed that these glycopeptides contained mostly carbohydrate (42.5 to 81.6%) and protein (4.3 to 11.3%), with lesser amounts of phosphorus (0.4 to 6.0%) and hexosamines (0.3 to 0.6%). Based upon total carbohydrate and monosaccharide content, these dermatophyte glycopeptides could be divided into two chemical groups: glucopeptides (DSI1) and mannopeptides (DSI2, DSII1, and DSII2). The mannopeptides and glucopeptides of each species of dermatophyte were not significantly different chemically from those derived from the other two dermatophyte species studied. Skin testing of DSI1-glycopeptides or DSI2-mannopeptides in immunized guinea pigs indicated that only the DSI2-mannopeptides elicited a delayed hypersensitivity reaction. Skin testing T. mentagrophytes 62-infected guinea pigs with the four purified DS-glycopeptides, as well as earlier fractions from the purification scheme, derived from T. mentagrophytes, T. rubrum, and M. canis, again indicated that only the DSI2-mannopeptides of the two Trichophyton species elicited a delayed hypersensitivity reaction. The number of infections or duration of infection had no effect on the size of the skin test response. DSI2-mannopeptides were non-cross-reactive between genera when tested in Trichophyton-immunized or -infected guinea pigs and Microsporum-immunized guinea pigs. Images PMID:640721

  20. 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.

  1. [Skin tests for trophallergens and asthma].

    PubMed

    Delacourt, C

    2002-12-01

    The place of trophallergens in the allergy investigation of asthmatic children is controversial. Asthma is only rarely the isolated manifestation of food allergy. The clinical history is essential for research of the associated signs that reveal a food allergy. In the absence of these associated signs, the presence of a positive test for trophallergens only rarely reflects a true food allergy, of which the presence can only be assured by a double blind oral provocation test. In addition, in nurslings, the presence of a positive skin test to a trophallergen indicates atopy in the infant, but is only a mediocre predictive factor of eventual asthma, in the absence of an associated clinical allergy.

  2. 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

    2013-02-01

    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.

  3. Controlling reactive oxygen species in skin at their source to reduce skin aging.

    PubMed

    Kern, Dale G; Draelos, Zoe D; Meadows, Christiaan; James Morré, D; Morré, Dorothy M

    2010-01-01

    Activity of an age-related, superoxide-forming, cell-surface oxidase (arNOX) comparing dermis, epidermis, serum, and saliva from female and male subjects ages 28-72 years measured spectrophotometrically using reduction of ferricytochrome c correlated with oxidative skin damage as estimated from autofluoresence of skin using an Advanced Glycation End products Reader (AGE-Reader; DiagnOptics B.V., Netherlands). By reducing arNOX activity in skin with arNOX-inhibitory ingredients (NuSkin's ageLOC technology), skin appearance was improved through decreased protein cross-linking and an accelerated increase in collagen.

  4. 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.

  5. Skin fungal biocontamination and the skin hydrogel pad test.

    PubMed

    Paquet, P; Piérard-Franchimont, C; Piérard, G E; Quatresooz, P

    2008-04-01

    Previous observations have revealed that environmental nondermatophyte molds (NDM) can grow inside specific hydrogel pads (LaserAid). Some of these NDM might be responsible for superficial and invasive mycoses as well as for allergic respiratory and cutaneous disorders. The load of NDM propagules in the environment is considered to be an important risk factor for all these diseases. It is postulated that the quantification of the responsible fungi deposited at the skin surface may be an indicator of a recent exposure to environmental fungi. The aim of the present study was to assess using the LaserAid hydrogel pads, the density of living NDM adhering to the skin surface of healthy subjects. Sterile hydrogel pads were applied in a repeat procedure onto the normal-looking skin of the palms and face of 35 healthcare workers who were active in low exposure areas. Similar samplings were performed after washing the skin with a regular skin cleanser, or after applying an alcohol solution or a povidone iodine solution. As controls, 20 sterile pads were exposed for a few minutes to ambient air of the laboratory without any contact with the skin. Each of these samples was stored for 2 weeks at room temperature in a clean protected environment. After that period, visual inspection of the pads was followed by microscopic examination of PAS-stained 6 microm-thick sections. In addition, mycological cultures were performed from pieces of the pads deposited onto Sabouraud agar plates. While 19/20 air-exposed samples were not contaminated by environmental air-borne fungi, 61/70 of the initial skin samplings and 6/70 of the repeat skin samplings showed foci of fungal colonization confirmed by microscopic examination. No specific differences were disclosed between the face and palm samplings. Cultures revealed the presence of NDM in the majority (64/67) of the colonized pads, and a few Candida albicans contaminations (3/67) were also disclosed. The cleansing with a non

  6. 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

  7. Development and Testing of Living Skin Equivalent.

    DTIC Science & Technology

    1988-05-01

    Model a) The use of Isografts in an inbred strain of rats. In a preliminary series of experiments the potential use of Fischer strain rats has been...tested by preparing a series of isografts made by grafting skin equivalents with cells from female donors to male hosts. On the average, wound...Autograft--rat 4 1 4 3 5 17 Autograft--rabbit 6 3 1 1 11 Isograft --rat 37 13 13 1 64 Allo fib., iso ker--rat 15 12 3 30 Allo fib, iso ker--rab 8 6 14 Iso

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

    PubMed Central

    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. Images PMID:3539805

  9. 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.

  10. Effects of skin cooling on airway reactivity in asthma.

    PubMed

    Skowronski, M E; Ciufo, R; Nelson, J A; McFadden, E R

    1998-05-01

    1. Environmental contact with cold air is a common cause of respiratory distress in obstructive lung disease, and direct and reflex changes in bronchial calibre are well documented with this stimulus when it is inhaled or contacts the exposed skin respectively. It is now known that skin chilling does not amplify the effects of breathing cold air, but it is not established if this lack of interaction is unique, or applies to other forms of airway constrictors. 2. To provide data on this issue, 10 subjects with atopic asthma underwent methacholine bronchoprovocations with and without chilling of the integument of their heads and thoraces for 30 min. Chilling was accomplished with a specially designed thermal garment. Spirometry as well as core and skin temperatures were serially monitored during all experiments. 3. In the control phase (no cooling), integumental temperatures rose slightly, the forced expiratory volume in 1.0 s (FEV1.0) did not change, and the mean provocative concentration of methacholine required to reduce the FEV1.0 by 20% (PC20 meth) was 0.47 +/- 0.17 mg/ml (2.4 +/- 0.87 mmol/l). In the cold trial, the temperature of the back fell 5.1 +/- 1.7 degrees C to 28.7 +/- 1.8 degrees C (P < 0.01), core temperatures did not change, and airway obstruction developed (delta FEV1.0 = -6.7 +/- 2.1%; P < 0.05). The PC20 meth, however, was unaltered [PC20 meth = 0.45 +/- 0.13 mg/ml (2.3 +/- 0.66 mmol/l); P = 0.85]. 4. These results demonstrate that although skin cooling produces mild airway obstruction in subjects with asthma, it does not change the response to non-specific bronchoconstrictors such as methacholine.

  11. Peptide reactivity assay using spectrophotometric method for high-throughput screening of skin sensitization potential of chemical haptens.

    PubMed

    Jeong, Yun Hyeok; An, Susun; Shin, Kyeho; Lee, Tae Ryong

    2013-02-01

    Haptens must react with cellular proteins to be recognized by antigen presenting cells. Therefore, monitoring reactivity of chemicals with peptide/protein has been considered an in vitro skin sensitization testing method. The reactivity of peptides with chemicals (peptide reactivity) has usually been monitored by chromatographic methods like HPLC or LC/MS, which are robust tools for monitoring common chemical reactions but are rather expensive and time consuming. Here, we examined the possibility of using spectrophotometric methods to monitor peptide reactivity. Two synthetic peptides, Ac-RWAACAA and Ac-RWAAKAA, were reacted with 48 chemicals (34 sensitizers and 14 non-sensitizers). Peptide reactivity was measured by monitoring unreacted peptides with UV-Vis spectrophotometer using 5,5'-dithiobis-2-nitrobenzoic acid as a detection reagent for the free thiol group of cysteine-containing peptide or fluorometer using fluorescamine™ as a detection reagent for the free amine group of lysine-containing peptide. Chemicals were categorized as sensitizers when they induced more than 10% depletion of cysteine-containing peptide or 20% depletion of lysine-containing peptide. The sensitivity, specificity, and accuracy of this method were 82.4%, 85.7%, and 83.3%, respectively. These results demonstrate that spectrophotometric methods can be easy, fast, and high-throughput screening tools for the prediction of the skin sensitization potential of chemical haptens.

  12. Human Herpesvirus-6 cytopathic inclusions: an exceptional and recognizable finding on skin biopsy during HHV6 reactivation after autologous stem-cell transplantation.

    PubMed

    Roux, Jennifer; Battistella, Maxime; Fornecker, Luc; Legoff, Jérôme; Deau, Bénédicte; Houhou, Nadira; Bouaziz, Jean-David; Thieblemont, Catherine; Janin, Anne

    2012-08-01

    Skin rash are common in immunocompromised patients, particularly after bone marrow transplantation. Human herpes virus 6 (HHV6) reactivation is often suspected, but its clinical presentation and the routine laboratory tests may be unspecific, thus leading to late diagnosis. In this case, we report specific intralymphocytic cytopathic inclusions on skin biopsy as a sign of systemic HHV6 reactivation. A 56-year-old patient presented progressive erythroderma and fever occurring after autologous hematopoietic stem-cell transplantation for mantle cell lymphoma. The skin biopsy showed a perivascular infiltrate of medium-to-large lymphocytes with irregular nuclei containing a large central basophilic inclusion surrounded by a clear halo. High levels of HHV-6 genomic in skin biopsy confirm HHV-6-induced cytopathic effect. The clinical course improved with intravenous foscavir. The specific histopathological findings encountered in this case are exceptional but recognizable, and along with HHV-6 DNA detection allow a prompt recognition of HHV6 skin rash.

  13. 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.

  14. Diagnosis of penicillin allergy by skin testing: the Manitoba experience.

    PubMed Central

    Warrington, R. J.; Simons, F. E.; Ho, H. W.; Gorski, B. A.

    1978-01-01

    The reliability of skin testing in the diagnosis of penicillin allergy was studied in 86 adults and 167 children with a history of possible hypersensitivity reactions to penicillin. Skin testing was done with the major antigenic determinant of benzylpenicillin and minor determinants of benzylpenicillin, ampicillin, cloxacillin, methicillin and cephalothin. The overall frequency of positive skin reactions was 11.5%. Among the patients with positive skin reactions about half had a history of immediate or accelerated reactions to penicillins, but 2 of 11 adults and 50% of the children in this group had a history of maculopapular rash of delayed onset. There was a low frequency of positive skin reactions when there was a long interval between the times of clinical reaction and skin testing. Of 169 patients reacting negatively to skin testing who received a specific drug challenge only 2 manifested mild urticaria; this indicates the reliability of the skin tests in predicting penicillin allergy. The major and minor determinants of benzylpenicillin were the most useful reagents. One fifth of the patients with penicillin hypersensitivity would have been missed if the major determinant of benzylpenicillin alone had been used for skin testing. The additional use of the minor determinants of other penicillin derivatives, however, did not increase substantially the clinical reliability of the skin testing procedure. PMID:638909

  15. Assessment of skin blood content and oxygenation in spinal cord injured subjects during reactive hyperemia.

    PubMed

    Hagisawa, S; Ferguson-Pell, M; Cardi, M; Miller, S D

    1994-01-01

    This study was undertaken to determine whether the reactive hyperemia response following ischemia in spinal cord injured (SCI) individuals is different from that which occurs in able-bodied (AB) individuals. The reactive hyperemia response was produced by applying a pressure of 150 mmHg for 300 s, 600 s, and 900 s to the skin over the greater trochanter in 10 SCI and 10 AB subjects using a computer-controlled pneumatic indentation system. The changes in blood content and oxygenation in the superficial vessels of the skin, associated with indentation, were monitored using reflectance spectrophotometry. A brief pressure of 80 mmHg, to simulate finger pressing (blanching), was applied to the same site to detect changes in reflow behavior during the hyperemic period. The results indicate that the reactive hyperemia response in SCI group was not substantially different from AB group although the reflow rate after load release was slower in the SCI group compared with the AB group.

  16. Observation of skin thermal inertia distribution during reactive hyperaemia using a single-hood measurement system.

    PubMed

    Hassan, M; Togawa, T

    2001-02-01

    An attempt was made to image the thermal inertia (defined as the square root of the product of thermal conductivity, specific heat and density) of the skin to observe the distribution of blood in the skin during post-occlusive reactive hyperaemia in normal healthy volunteers. The method was based on the ability to calculate thermal inertia by successive thermographic measurements of the skin after stepwise change in ambient radiation temperature surrounding the skin area. The stepwise change was achieved within 0.1 s through a single hood. Experimentation on the undisturbed volar forearm of normal subjects at the same site showed that the measurements thus achieved were reproducible. The thermal inertia values of forearm skin in normal subjects were scattered throughout the range 1.1 x 10(3) to 1.7 x 10(3) W s(1/2) m(-2) K(-1). Experiments on forearm skin subjected to arterial cuff occlusion indicated that thermal inertia can be detected at a low level of blood perfusion. A linear relationship was observed between thermal inertia and blood perfusion measured by laser Doppler imager before and during blood flow occlusion. During reactive hyperaemia, the thermal inertia image exhibited a non-uniform island-shaped pattern of distribution over the forearm, suggesting that, after release from occlusion, recovery of blood flow is non-uniform.

  17. 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

  18. Relating skin sensitizing potency to chemical reactivity: reactive Michael acceptors inhibit NF-κB signaling and are less sensitizing than S(N)Ar- and S(N)2- reactive chemicals.

    PubMed

    Natsch, Andreas; Haupt, Tina; Laue, Heike

    2011-11-21

    The skin sensitization potency of chemicals is partly related to their reactivity to proteins. This can be quantified as the rate constant of the reaction with a model peptide, and a kinetic profiling approach to determine rate constants was previously proposed. A linear relationship between the skin sensitization potency in the local lymph node assay (LLNA) and the rate constant for Michael acceptors was reported, characterized by a relatively flat regression line. Thus, a 10-fold increase of reactivity correlates to an increase of the sensitization potential of only 1.7-fold. Here, we first validate this model by repeating previous data and testing additional Michael acceptors and prove that the model is both reproducible and robust to the addition of new data. Chemicals of different mechanistic applicability domains, namely, S(N)Ar- and S(N)2-reactive sensitizers, were then tested with the same kinetic profiling approach. A linear relationship between sensitization potency in the LLNA and rate constants was also found, yet with a much steeper slope, i.e., for S(N)Ar- and S(N)2-reactive sensitizers, increasing reactivity correlates to a much stronger increase in sensitization potency. On the basis of the well-known inhibitory activity of some Michael acceptors on IKK kinase, it was hypothesized that the difference in the slopes is due to the specific anti-inflammatory potential of Michael acceptor chemicals. Therefore, all chemicals were tested for anti-inflammatory activity in a reporter gene assay for the inhibition of NF-κB activation. Increasingly reactive Michael acceptors have increasing anti-inflammatory potential in this assay, whereas no such biological activity was detected for the S(N)Ar and S(N)2 reactive sensitizers. Thus, the increasing reactivity of Michael acceptors confers both anti-inflammatory and skin sensitizing/pro-inflammatory potential, which may partially neutralize each other. This may be the reason for the relatively weak relationship

  19. Integrating non-animal test information into an adaptive testing strategy - skin sensitization proof of concept case.

    PubMed

    Jaworska, Joanna; Harol, Artsiom; Kern, Petra S; Gerberick, G Frank

    2011-01-01

    There is an urgent need to develop data integration and testing strategy frameworks allowing interpretation of results from animal alternative test batteries. To this end, we developed a Bayesian Network Integrated Testing Strategy (BN ITS) with the goal to estimate skin sensitization hazard as a test case of previously developed concepts (Jaworska et al., 2010). The BN ITS combines in silico, in chemico, and in vitro data related to skin penetration, peptide reactivity, and dendritic cell activation, and guides testing strategy by Value of Information (VoI). The approach offers novel insights into testing strategies: there is no one best testing strategy, but the optimal sequence of tests depends on information at hand, and is chemical-specific. Thus, a single generic set of tests as a replacement strategy is unlikely to be most effective. BN ITS offers the possibility of evaluating the impact of generating additional data on the target information uncertainty reduction before testing is commenced.

  20. 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.

  1. Quiz: Test Your Skin Cancer IQ

    MedlinePlus

    ... vaccines might be used to prevent melanoma prevent polio treat melanoma A is the correct answer. Skin ... similar to traditional vaccines, like those that prevent polio, but cancer vaccines are given as treatment to ...

  2. 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.

  3. Use of recombinant purified protein derivative (PPD) antigens as specific skin test for tuberculosis

    PubMed Central

    Stavri, Henriette; Bucurenci, Nadia; Ulea, Irina; Costache, Adriana; Popa, Loredana; Popa, Mircea Ioan

    2012-01-01

    Background & objectives: Purified protein derivative (PPD) is currently the only available skin test reagent used worldwide for the diagnosis of tuberculosis (TB). The aim of this study was to develop a Mycobacterium tuberculosis specific skin test reagent, without false positive results due to Bacillus Calmette-Guerin (BCG) vaccination using recombinant antigens. Methods: Proteins in PPD IC-65 were analyzed by tandem mass spectrometry and compared to proteins in M. tuberculosis culture filtrate; 54 proteins were found in common. Top candidates MPT64, ESAT 6, and CFP 10 were overexpressed in Escherichia coli expression strains and purified as recombinant proteins. To formulate optimal immunodiagnostic PPD cocktails, the antigens were evaluated by skin testing guinea pigs sensitized with M. tuberculosis H37Rv and BCG. Results: For single antigens and a cocktail mixture of these antigens, best results were obtained using 3 μg/0.1 ml, equivalent to 105 TU (tuberculin units). Each animal was simultaneously tested with PPD IC-65, 2 TU/0.1 ml, as reference. Reactivity of the multi-antigen cocktail was greater than that of any single antigen. The skin test results were between 34.3 and 76.6 per cent the level of reactivity compared to that of the reference when single antigens were tested and 124 per cent the level of reactivity compared to the reference for the multi-antigen cocktail. Interpretation & conclusions: Our results showed that this specific cocktail could represent a potential candidate for a new skin diagnostic test for TB. PMID:23287127

  4. Testing of Raman spectroscopy method for assessment of skin implants

    NASA Astrophysics Data System (ADS)

    Timchenko, E. V.; Timchenko, P. E.; Volova, L. T.; Pershutkina, S. V.; Shalkovskaya, P. Y.

    2016-11-01

    Results of studies of testing of Raman spectroscopy (RS) method for assessment of skin implants are presented. As objects of study were used samples of rat's skin material. The main spectral differences of implants using various types of their processing appear at wavenumbers 1062 cm-1, 1645 cm-1, 1553 cm-1, 851 cm-1, 863 cm-1, 814 cm-1 and 1410 cm-1. Optical coefficients for assessment of skin implants were introduced. The research results are confirmed by morphological analysis.

  5. 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.

  6. Caffeine protects human skin fibroblasts from acute reactive oxygen species-induced necrosis.

    PubMed

    Silverberg, Jonathan I; Patel, Mital; Brody, Neil; Jagdeo, Jared

    2012-11-01

    Oxidative damage by reactive oxygen species (ROS) plays a major role in aging and carcinogenesis. Little is known about either the effects of acute ROS in necrosis and inflammation of skin or the therapeutic agents for prevention and treatment. Previously, our laboratory identified caffeine as an inhibitor of hydrogen peroxide (H2O2)-generated lipid peroxidation products in human skin fibroblasts. Here, we study effects of caffeine on acute ROS-mediated necrosis. Human skin fibroblasts were incubated with caffeine, followed by H2O2 challenge. Flow cytometry was used to analyze cell morphology, counts, apoptosis and necrosis, and ROS. We found that caffeine protects from H2O2 cell damage at lower (0.01 mM) and intermediate (0.1 mM) doses. The beneficial effects of caffeine appear to be mediated by a mechanism other than antioxidant function.

  7. Cutaneous tuberculosis with nonreactive PPD skin test: a diagnostic challenge*

    PubMed Central

    Nassif, Priscila Wolf; Rosa, Ana Paula Zanatta; Gurgel, Ana Cristina Medeiros; Campanerut, Paula Aline Zanetti; Fillus Neto, José; Cardoso, Rosilene Fressatti

    2015-01-01

    The authors report a case of cutaneous tuberculosis in a 63-year-old female patient, who had an infiltrated, erythematous-ferruginous plaque of indurated aspect on her right leg and a nonreactive PPD skin test. Diagnosis was made by tissue culture and PCR of skin biopsy material. The treatment was performed with pyrazinamide, rifampicin, isoniazid and ethambutol, with good response. PMID:25672314

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

    PubMed Central

    Kabali, Conrad; Chan, Brian; Higgins, Caroline; Holubowich, Corinne

    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

  9. Predicting which medication classes interfere with allergy skin testing.

    PubMed

    Shah, Kunal M; Rank, Matthew A; Davé, Shoban A; Oslie, Corrine L; Butterfield, Joseph H

    2010-01-01

    Medications often interfere with allergy skin test interpretation. This study was performed to determine which medications interfere with allergy skin tests. We retrospectively reviewed skin-prick test results from patients who had discontinued H(1)-antagonists, tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), selective norepinephrine reuptake inhibitors (SNRIs), benzodiazepines, atypical antidepressants, antipsychotics, hypnotics, sedatives, proton pump inhibitors (PPIs), and H(2)-antagonists between 0 and 7 days before allergy skin testing. Ninety-seven subjects had taken second-generation H(1)-antihistamines within 7 days of skin testing; all patients who had stopped 3 days before testing had positive histamine controls. Two hundred sixty-eight skin tests performed on patients taking a single medication of interest showed that patients had the following percentages of a positive histamine control: TCAs, 56.5%; SNRIs, 100%; H(2)-blockers, 100%; SSRIs, 97%; PPIs, 97%; benzodiazepines, 85.7%; and atypical antidepressants/sedatives, 92.6%. The 580 patients taking multiple medications of interest showed that the odds ratio and 95% confidence intervals of a negative histamine test for patients taking TCAs were 6.33 (2.11-20.5), for H(1)-blockers were 4.95 (1.78-15.1), for benzodiazepines were 5.01 (1.72-15.80), for atypical antidepressants/sedatives were 3.11 (1.09-9.61), and for H(2)-blockers were 2.91 (0.97-9.37). The odds of a negative histamine test for SSRIs, SNRIs, or PPIs were not significantly increased. SSRIs, SNRIs, and PPIs are unlikely to interfere with skin testing. TCAs, H(1)-blockers, benzodiazepines, quetiapine, and mirtazapine should be discontinued temporarily if clinically able. H(2)-antagonists, bupropion, eszopiclone, trazodone, or zolpidem showed minimal interference with immediate hypersensitivity skin test histamine response.

  10. Relational victimization and proactive versus reactive relational aggression: The moderating effects of respiratory sinus arrhythmia and skin conductance.

    PubMed

    Wagner, Caitlin R; Abaied, Jamie L

    2015-01-01

    This research examined the moderating effect of the autonomic nervous system (ANS) on the associations between relational victimization and reactive and proactive relational aggression. Both branches of the ANS, the parasympathetic nervous system (indexed by respiratory sinus arrhythmia reactivity; RSA-Reactivity) and the sympathetic nervous system (indexed by skin conductance level reactivity; SCL-Reactivity), were examined. Emerging adults (N = 168) self-reported on relational victimization and proactive and reactive relational aggression; RSA-Reactivity and SCL-Reactivity were assessed in response to a laboratory stressor. Relational victimization predicted heightened reactive relational aggression given RSA augmentation/high SCL-Reactivity (i.e., coactivation) and RSA withdrawal/low SCL-Reactivity (i.e., coinhibition). In addition, relational victimization predicted heightened reactive relational aggression given RSA augmentation/low SCL-Reactivity (i.e., reciprocal parasympathetic activation). This study extends previous research on relational victimization and provides novel evidence that (a) exposure to relational victimization is associated with reactive relational aggression, but not proactive relational aggression, and (b) parasympathetic and sympathetic nervous system reactivity jointly moderate the link between relational victimization and reactive relational aggression.

  11. Contributions of Observed Parent Socialization of Coping and Skin Conductance Level Reactivity to Childhood Adjustment.

    PubMed

    Stanger, Sarah; Abaied, Jamie; Wagner, Caitlin; Sanders, Wesley

    2016-12-18

    This research examined the longitudinal association between parent socialization of coping and child adjustment, as well as the moderating role of children's skin conductance level reactivity (SCLR). Participants were a community sample of children (n = 64, M age = 9.02, 54.5% females, 93.2% Caucasian) and their parent(s). Parent coping suggestions were observed while their child engaged in a stressful challenge task, during which the child's SCLR, a measure of children's physiological reactivity to stress, was also measured. Parent(s) completed the Child Behavior Checklist (Achenbach & Rescorla, 2001) at baseline and a 6-month follow-up to assess internalizing and externalizing problems. Results revealed that secondary control engagement suggestions predicted fewer internalizing problems over time. In addition, disengagement suggestions predicted fewer externalizing problems over time among children with high SCLR. This study provides evidence that parent coping suggestions serve as a resource that protects youth from developing adjustment problems.

  12. Biological features of the skin of the pika, Ochotona rufescens rufescens: histological structure and enzymatic histochemical reactivity.

    PubMed

    Sakai, T; Yamada, S; Taniguchi, Y; Kodama, S; Horiuchi, S; Nomura, T

    1987-04-01

    To examine the usefulness of the pika, Ochotona rufescens rufescens, as an experimental animal for skin irritability tests, the histological structure and enzymatic histochemical reactivity of pika skin were investigated. The pika had a hair cycle similar to that of the rabbit. The skin and epidermis of the pika trunk were 1.16mm and 29.5 microns thick, on the average, respectively. Both of them were the thickest in the dorsal region followed by the interscapular area, while they were the thinnest in the abdominal region. In the epidermis of the pika, the strata corneum, granulosum, spinosum and basale were rather clearly distinguished. The cell arrangement in the stratum basale was more compact than that in the rabbit. Dermal mast cells, which are distributed in the stratum reticulare in rabbits and guinea pigs, were distributed in the stratum papillare right beneath the epidermis. The mast cell of the pika in the TEM images had granules of low electron density and with relatively long microvilli and rather large mitochondria. The activities of the enzymes, SDH, MDH, LDH, beta HBDH, alpha GPDH, ALD, G6PDH and GPR, in the hair follicles and sebaceous glands of the pika were similar to those of the rabbit.

  13. 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

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

    PubMed

    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

  15. The lupus band test in oral mucosa, conjunctiva and skin.

    PubMed

    Burge, S M; Frith, P A; Millard, P R; Wojnarowska, F

    1989-12-01

    The prevalence and clinical significance of subepithelial immunoglobulin and complement deposition (the lupus band) were examined in the uninvolved sun-protected skin of the forearm, the uninvolved sun-protected lip mucosa and sun-protected bulbar conjunctival mucosa in systemic lupus erythematosus (SLE) and chronic cutaneous lupus erythematosus (CCLE). In SLE, linear deposition of an immunoreactant at the BMZ was detected in 32% (6/19) of skin biopsies; 21% (4/19) of lip mucosal biopsies and 42% (5/12) of conjunctival biopsies. There was no significant difference in the sensitivity of the test at different sites in SLE and no correlation between a positive test in skin, lip or conjunctiva and clinical mucosal involvement. In CCLE, linear deposition of an immunoreactant at the BMZ was found in 3% (1/32) of skin biopsies; 3% (1/29) of lip mucosal biopsies and 50% (10/20) of conjunctiva and clinical mucosal involvement. In the conjunctiva, IgG was present in all but one of the biopsies and was the only immunoreactant in 90% (9/10) of positive CCLE biopsies and 60% (3/5) of positive SLE biopsies. In lupus erythematosus immunoreactants may be deposited in the basement membrane zone beneath non-keratinizing mucosal surfaces of the lip and the eye as well as the skin. In CCLE, the test may be positive in conjunctiva when skin and lip are negative.

  16. Diagnostic tools for hypersensitivity to platinum drugs and taxanes: skin testing, specific IgE, and mast cell/basophil mediators.

    PubMed

    Caiado, Joana; Picard, Matthieu

    2014-08-01

    Hypersensitivity reactions (HSRs) to platinum drugs and taxanes are increasing in cancer patients, and rapid drug desensitization has emerged as a safe and effective method to reintroduce these drugs in reactive patients. Optimal management of patients presenting HSRs to chemotherapy depends on the use of various diagnostic tools, which include measurement of mast cell/basophil mediator release following a HSR and skin testing. Serum tryptase should be measured in patients presenting chemotherapy HSRs, and its elevation would support mast cell/basophil activation. Skin testing to platinum drugs has a high sensitivity and specificity and is critical to guide the management of platinum-reactive patients. Taxane skin testing is also emerging as a useful diagnostic and risk stratification tool in the evaluation of patients with HSRs to taxanes. Platinum sIgE assays have been recently developed and can be helpful in combination with skin testing or as an alternative when skin testing is not available.

  17. The effect of venom skin testing on venom RAST titers.

    PubMed

    Green, R L; Levine, M I

    1982-03-01

    Venom RAST titers were measured in 20 insect-sensitive patients before and two to three weeks after skin testing with insect venoms to determine whether venom testing might cause a rise in venom IgE titers. No significant rise in venom-specific RAST titers for honey bee, wasp and yellow jacket venoms was observed.

  18. 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.

  19. 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.

  20. Penicillin skin testing: potential implications for antimicrobial stewardship.

    PubMed

    Unger, Nathan R; Gauthier, Timothy P; Cheung, Linda W

    2013-08-01

    As the progression of multidrug-resistant organisms and lack of novel antibiotics move us closer toward a potential postantibiotic era, it is paramount to preserve the longevity of current therapeutic agents. Moreover, novel interventions for antimicrobial stewardship programs are integral to combating antimicrobial resistance worldwide. One unique method that may decrease the use of second-line antibiotics (e.g., fluoroquinolones, vancomycin) while facilitating access to a preferred β-lactam regimen in numerous health care settings is a penicillin skin test. Provided that up to 10% of patients have a reported penicillin allergy, of whom ~10% have true IgE-mediated hypersensitivity, significant potential exists to utilize a penicillin skin test to safely identify those who may receive penicillin or a β-lactam antibiotic. In this article, we provide information on the background, associated costs, currently available literature, pharmacists' role, antimicrobial stewardship implications, potential barriers, and misconceptions, as well as future directions associated with the penicillin skin test.

  1. Non-animal testing strategies for assessment of the skin corrosion and skin irritation potential of ingredients and finished products.

    PubMed

    Robinson, M K; Cohen, C; de Fraissinette, A de Brugerolle; Ponec, M; Whittle, E; Fentem, J H

    2002-05-01

    The dermatotoxicologist today is faced with a dilemma. Protection of workers and consumers from skin toxicities (irritation and allergy) associated with exposure to products, and the ingredients they contain, requires toxicological skin testing prior to manufacture, transport, or marketing. Testing for skin corrosion or irritation has traditionally been conducted in animals, particularly in rabbits via the long established Draize test method. However, this procedure, among others, has been subject to criticism, both for its limited predictive capacity for human toxicity, as well as for its use of animals. In fact, legislation is pending in the European Union which would ban the sale of cosmetic products, the ingredients of which have been tested in animals. These considerations, and advancements in both in vitro skin biology and clinical testing, have helped drive an intensive effort among skin scientists to develop alternative test methods based either on in vitro test systems (e.g. using rat, pig or human skin ex vivo, or reconstructed human skin models) or ethical clinical approaches (human volunteer studies). Tools are now in place today to enable a thorough skin corrosion and irritation assessment of new ingredients and products without the need to test in animals. Herein, we describe general testing strategies and new test methods for the assessment of skin corrosion and irritation. The methods described, and utilized within industry today, provide a framework for the practicing toxicologist to support new product development initiatives through the use of reliable skin safety testing and risk assessment tools and strategies.

  2. 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.

  3. 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

    ... niceatm@niehs.nih.gov are preferred. NICEATM, National Institute of Environmental Health Sciences, P.O... direct contact with a skin allergen, is an important public health challenge. ACD frequently develops in... chemico or in vitro methods (the direct peptide reactivity assay, human cell line activation...

  4. Provocative Testing for Coronary Reactivity and Spasm

    PubMed Central

    Zaya, Melody; Mehta, Puja K.; Merz, C. Noel Bairey

    2014-01-01

    Coronary spasm is an important and often overlooked etiology of chest pain. While coronary spasm, or Prinzmetal’s angina, has been thought of as benign, contemporary studies have shown serious associated adverse outcomes including acute coronary syndrome, arrhythmia, and death. Definitive diagnosis of coronary spasm can at times be difficult given the transience of symptoms. Numerous agents have been historically described for provocative testing. We provide a review of literature for the role of provocation testing in the diagnosis of coronary spasm. PMID:24201078

  5. Chemical reactivity and skin sensitization potential for benzaldehydes: can Schiff base formation explain everything?

    PubMed

    Natsch, Andreas; Gfeller, Hans; Haupt, Tina; Brunner, Gerhard

    2012-10-15

    Skin sensitizers chemically modify skin proteins rendering them immunogenic. Sensitizing chemicals have been divided into applicability domains according to their suspected reaction mechanism. The widely accepted Schiff base applicability domain covers aldehydes and ketones, and detailed structure-activity-modeling for this chemical group was presented. While Schiff base formation is the obvious reaction pathway for these chemicals, the in silico work was followed up by limited experimental work. It remains unclear whether hydrolytically labile Schiff bases can form sufficiently stable epitopes to trigger an immune response in the living organism with an excess of water being present. Here, we performed experimental studies on benzaldehydes of highly differing skin sensitization potential. Schiff base formation toward butylamine was evaluated in acetonitrile, and a detailed SAR study is presented. o-Hydroxybenzaldehydes such as salicylaldehyde and the oakmoss allergens atranol and chloratranol have a high propensity to form Schiff bases. The reactivity is highly reduced in p-hydroxy benzaldehydes such as the nonsensitizing vanillin with an intermediate reactivity for p-alkyl and p-methoxy-benzaldehydes. The work was followed up under more physiological conditions in the peptide reactivity assay with a lysine-containing heptapeptide. Under these conditions, Schiff base formation was only observable for the strong sensitizers atranol and chloratranol and for salicylaldehyde. Trapping experiments with NaBH₃CN showed that Schiff base formation occurred under these conditions also for some less sensitizing aldehydes, but the reaction is not favored in the absence of in situ reduction. Surprisingly, the Schiff bases of some weaker sensitizers apparently may react further to form stable peptide adducts. These were identified as the amides between the lysine residues and the corresponding acids. Adduct formation was paralleled by oxidative deamination of the parent

  6. Increased Expression of Versican in the Inflammatory Response to UVB- and Reactive Oxygen Species-Induced Skin Tumorigenesis

    PubMed Central

    Kunisada, Makoto; Yogianti, Flandiana; Sakumi, Kunihiko; Ono, Ryusuke; Nakabeppu, Yusaku; Nishigori, Chikako

    2011-01-01

    Excessive exposure to UV radiation is a major risk factor for developing skin cancer. UV-induced reactive oxygen species (ROS) cause accumulation of DNA damage products such as 8-oxoguanine (8-oxoG) in the skin. We have previously shown that mice lacking the repair enzyme 8-oxoguanine glycosylase (Ogg1 knockout mice) are highly susceptible to skin cancer after long-term UVB exposure. To investigate the genes involved, we performed gene profiling of Ogg1 knockout mouse skin after UVB exposure. Among the up-regulated genes in UVB-treated Ogg1 knockout mice, inflammatory response pathway-related genes were most affected. The Vcan gene, which encodes the large extracellular matrix proteoglycan versican, was continuously up-regulated in UVB-treated Ogg1 knockout mice, suggesting that versican is a mediator of skin cancer development. We examined the expression pattern of versican in skin tumors from wild-type mice and UVB-treated Ogg1 knockout mice, and also analyzed 157 sun-related human skin tumors. Versican was strongly expressed in malignant skin tumors in both mice and humans, and especially in Ogg1 knockout mice. Additionally, infiltrating neutrophils strongly colocalized with versican in UVB-treated Ogg1 knockout mouse skin. These data demonstrate that inflammatory responses, particularly neutrophil infiltration and versican up-regulation, are closely involved in UVB/ROS-induced skin tumorigenesis. PMID:22001346

  7. 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

  8. Parameters estimation for reactive transport: A way to test the validity of a reactive model

    NASA Astrophysics Data System (ADS)

    Aggarwal, Mohit; Cheikh Anta Ndiaye, Mame; Carrayrou, Jérôme

    The chemical parameters used in reactive transport models are not known accurately due to the complexity and the heterogeneous conditions of a real domain. We will present an efficient algorithm in order to estimate the chemical parameters using Monte-Carlo method. Monte-Carlo methods are very robust for the optimisation of the highly non-linear mathematical model describing reactive transport. Reactive transport of tributyltin (TBT) through natural quartz sand at seven different pHs is taken as the test case. Our algorithm will be used to estimate the chemical parameters of the sorption of TBT onto the natural quartz sand. By testing and comparing three models of surface complexation, we show that the proposed adsorption model cannot explain the experimental data.

  9. 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).

  10. 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.

  11. Postocclusive reactive hyperemia and thermal response in the skin microcirculation of subjects with spinal cord injury.

    PubMed

    Schubert, V; Fagrell, B

    1991-01-01

    The response of skin blood cell flux (SBF) to locally applied pressure was evaluated by laser Doppler fluxmetry over the sacrum and the gluteus maximus muscle in twenty patients with spinal cord injuries (SCI)-ten with tetraplegia, ten with paraplegia-and ten healthy subjects. The SCI patients were further divided into two subgroups, one with sensation and the other without sensation over the sacrum area. The SBF over the sacrum, without applied pressure, showed somewhat higher values among the patients. The ten paraplegic patients (p less than 0.05) and the subgroup of patients without sensation over the sacrum (p less than 0.05) showed the highest values. Occlusion of the SBF was reached at a lower external skin pressure over the sacrum than over the gluteus maximus muscle in the group with spinal cord injuries (p less than 0.01). During the postocclusive reactive hyperemia we found a much shorter time to peak SBF over the gluteus muscle for the patients compared to the healthy subjects (p less than 0.01). In the subgroup of patients without sensation over the sacrum a prolonged time to peak SBF was found (p less than 0.01) over the sacrum compared to patients with sensation and to healthy subjects. The increase of the SBF during postocclusive hyperemia response was lower over both the sacrum and the gluteus maximus muscle areas in the patients with spinal cord injuries (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Modulating the reactivity of Ni-containing Pt(111)-skin catalysts by density functional theory calculations

    NASA Astrophysics Data System (ADS)

    Su, Hai-Yan; Bao, Xin-He; Li, Wei-Xue

    2008-05-01

    We present here a first principles density functional theory investigation of the reactivity of Pt(111)-skin catalysts, which are varied from surface alloys with Ni to bulk PtxNi1-x (x=0.25,0.50,0.75) alloys. Molecule (CO, O, and H) adsorption and oxidation of CO +O and H +O reactions were studied and analyzed in detail. Independent of the adsorbates, the interaction between adsorbates and substrates becomes weakened with increase in Ni, due to the downshift of d-band center of surface Pt atoms. Moreover, activation barriers of CO and H oxidation toward atomic oxygen gradually decrease. In term of CO preferential oxidation (PROX) in excess of hydrogen, it turns out that the overall reactivity and selectivity rely on the optimum of various elementary steps involved such as competitive molecular (dissociative) adsorption and oxidation reaction. The present calculations show that Pt3Ni(111) with Pt overlayer is an optimum catalyst for CO PROX in excess of hydrogen.

  13. Modulating the reactivity of Ni-containing Pt(111)-skin catalysts by density functional theory calculations.

    PubMed

    Su, Hai-Yan; Bao, Xin-He; Li, Wei-Xue

    2008-05-21

    We present here a first principles density functional theory investigation of the reactivity of Pt(111)-skin catalysts, which are varied from surface alloys with Ni to bulk PtxNi 1-x (x=0.25,0.50,0.75) alloys. Molecule (CO, O, and H) adsorption and oxidation of CO+O and H+O reactions were studied and analyzed in detail. Independent of the adsorbates, the interaction between adsorbates and substrates becomes weakened with increase in Ni, due to the downshift of d-band center of surface Pt atoms. Moreover, activation barriers of CO and H oxidation toward atomic oxygen gradually decrease. In term of CO preferential oxidation (PROX) in excess of hydrogen, it turns out that the overall reactivity and selectivity rely on the optimum of various elementary steps involved such as competitive molecular (dissociative) adsorption and oxidation reaction. The present calculations show that Pt3Ni(111) with Pt overlayer is an optimum catalyst for CO PROX in excess of hydrogen.

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

    PubMed Central

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

    2014-01-01

    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

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

    PubMed

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

    2015-02-07

    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.

  16. Skin sensitisation: the Colipa strategy for developing and evaluating non-animal test methods for risk assessment.

    PubMed

    Maxwell, Gavin; Aeby, Pierre; Ashikaga, Takao; Bessou-Touya, Sandrine; Diembeck, Walter; Gerberick, Frank; Kern, Petra; Marrec-Fairley, Monique; Ovigne, Jean-Marc; Sakaguchi, Hitoshi; Schroeder, Klaus; Tailhardat, Magali; Teissier, Silvia; Winkler, Petra

    2011-01-01

    Allergic contact dermatitis is a delayed-type hypersensitivity reaction induced by small reactive chemicals (haptens). Currently, the sensitising potential and potency of new chemicals is usually characterised using data generated via animal studies, such as the local lymph node assay (LLNA). There are, however, increasing public and political concerns regarding the use of animals for the testing of new chemicals. Consequently, the development of in vitro, in chemico or in silico models for predicting the sensitising potential and/or potency of new chemicals is receiving widespread interest. The Colipa Skin Tolerance task force currently collaborates with and/or funds several academic research groups to expand our understanding of the molecular and cellular events occurring during the acquisition of skin sensitisation. Knowledge gained from this research is being used to support the development and evaluation of novel alternative approaches for the identification and characterisation of skin sensitizing chemicals. At present three non-animal test methods (Direct Peptide Reactivity Assay (DPRA), Myeloid U937 Skin Sensitisation Test (MUSST) and human Cell Line Activation Test (hCLAT)) have been evaluated in Colipa interlaboratory ring trials for their potential to predict skin sensitisation potential and were recently submitted to ECVAM for formal pre-validation. Data from all three test methods will now be used to support the study and development of testing strategy approaches for skin sensitiser potency prediction. This publication represents the current viewpoint of the cosmetics industry on the feasibility of replacing the need for animal test data for informing skin sensitisation risk assessment decisions.

  17. 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.

  18. Construction of three-dimensional dermo-epidermal skin equivalents using cell coating technology and their utilization as alternative skin for permeation studies and skin irritation tests.

    PubMed

    Akagi, Takami; Nagura, Mayuka; Hiura, Ayami; Kojima, Hajime; Akashi, Mitsuru

    2017-03-23

    In vitro generated human skin equivalents are generating interest as promising tools in basic research, as alternatives to animal testing and for clinical applications in regenerative medicine. For prediction of skin irritation and corrosion, three-dimensional (3D) human skin equivalents consisting of differentiated human keratinocytes have been developed and some models have been internationally accepted. However, more delicate assessments using full-thickness skin models, such as skin sensitization tests cannot be performed because of the lack of a dermis containing fibroblasts or appendages. In a previous study, we developed dermo-epidermal human skin equivalents (DESEs) using a cell coating technique, which employs cell surface coating by layer-by-layer (LbL) assembled extracellular matrix (ECM) films. The DESEs with dermis consisting of normal human dermal fibroblasts (NHDF) and epidermis consisting of human keratinocytes (KC) were easily fabricated by using this technology. In this study, the constructed DESEs were evaluated as an alternative skin for skin permeation and irritation tests. A good relationship of permeability coefficient of chemicals was observed between the DESEs and human skin data. We investigated whether the DESEs, a new in vitro skin model, are able to identify skin irritant and non-irritant substances among 20 reference chemicals. It was confirmed that the DESEs are applicable to skin irritation testing as defined in the European Centre for the Validation of Alternative Methods (ECVAM) Performance Standard (OECD Test Guideline 439). We further studied the construction of the DESEs with density-controlled blood capillary networks using human umbilical vein endothelial cells (HUVEC). The results suggest that DESEs allowing incorporation of skin appendages are more promising alternatives to animal testing, and can be applied to the design of physiologically relevant in vitro skin models.

  19. 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.

  20. Comparison of the brucellin skin test with the lymphocyte transformation test in bovine brucellosis.

    PubMed Central

    Chukwu, C. C.

    1986-01-01

    The brucellin skin test and the lymphocyte transformation test were compared in heifers infected with virulent Brucella abortus strain 544, heifers vaccinated against brucellosis and unexposed cattle. Results of the in vitro lymphocyte transformation test were consistently positive for all 9 Brucella-infected heifers while the skin test was consistently positive for 6 of the 9 heifers. In 7 heifers repeatedly vaccinated with B. abortus strain-19 vaccine the in vitro test classified 3 animals as positive whereas the skin test identified all the animals as infected during most of the experimental period. Four heifers injected with a single dose of B. abortus strain 19 were consistently negative to the lymphocyte transformation test while the skin test classified all the animals as infected during most of the experimental period. The skin test gave strong reactions indicative of Brucella infection in heifers vaccinated with 'Duphavac' and 'Abortox' vaccines whereas the lymphocyte transformation test was consistently negative with these vaccines. The two tests were negative in unexposed cattle. It was concluded that the in vitro test correlated better with Brucella isolation than the in vivo test did and that the lack of agreement between the results of the two tests is likely to be due to the different antigens used in the assays. PMID:3734426

  1. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 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...

  2. Advanced Development of Leishmania Topical Skin Test Antigen

    DTIC Science & Technology

    2012-09-28

    Qualification of Cell Substrates and Other Biological Materials Used in the Production of Viral Vaccines for Infectious Disease Indications"(2010). The tests...product formulation was a phosphate buffer system as formulated below: 12.5mM Na2HPO4 12.5mM NaH2PO4 8.5% NaCl 0.4% Phenol 1.0% Glycerol 0.01...prior infection with the parasite. The test is commonly used to screen candidates in Leishmania vaccine trials. The skin test also has been used as a

  3. [Aeroallergens, skin tests and allergic diseases in 1091 patients].

    PubMed

    Enríquez Palomec, O; Hernández Chávez, L; Sarrazola Sanjuan, D M; Segura Méndez, N H; Hernández Colín, D D; Martínez-Cairo, S

    1997-01-01

    To know the frequency of positively of several skin tests, data cards from patients, of the Allergy and Clinic Immunology Service of the Hospital de Especialidades del Centro Medico Nacional Siglo XXI (Mexico City), between January, 1989 and March, 1995, were reviewed. Aqueous extracts manufactures by our laboratory were applied, in a dilution of 1:1000 weight-volume. 1091 from 5,651 skin tests patients were positive. Asthma and rhinitis were diagnosed in 492, allergic rhinitis in 289, allergic asthma in 111, and other diagnosis in 199 cases. The most frequent inhalable aeroallergens were house dust and perennial Dermatophagoides p and f1 with predominance in the rainy season, followed by pollens from Fraxinus a. Quercus a and Capriola, with predominance in the rainy season. The most frequent fungi were Candida and Fusarium, with predominance in the dry season.

  4. Development and Production of a Leishmania Skin Test

    DTIC Science & Technology

    2009-03-01

    indurated border will be outlined as a solid line with a ballpoint pen . Erythema will be outlined with a broken (dotted) line. The tracing will be...shall be reported as mm edema/mm erythema. Skin tests read at 48 ± 6 hours shall be recorded in mm induration using the ballpoint pen method. (19...10.6.2.4 Measuring and Recording Induration The area of induration (firmness) shall be outlined with a ballpoint pen . A permanent record of the reaction

  5. Antimicrobial efficacy of biocides tested on skin using an ex-vivo test.

    PubMed

    Maillard, J Y; Messager, S; Veillon, R

    1998-12-01

    An ex-vivo test was used to evaluate the activity of antimicrobials against three microorganisms, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The ex-vivo test is a carrier test using freshly excised animal skin samples maintained in viable conditions for a short period of time. Skin samples came from a veterinary practice and were excised from either dogs or cats. The antimicrobial activity of povidone iodine, chlorhexidine diacetate, cetrimide and benzalkonium chloride was also evaluated with suspension and glass-carrier tests. Generally, the activity of the antimicrobials tested was reduced when applied to the skin surface. Apart from povidone iodine (2%) against S. aureus, the biocides investigated failed to achieve a 5 log10 reduction in bacterial titre when tested with the ex-vivo method. There was no significant difference in reduction of bacterial titres after treatment with antimicrobials between the glass-carrier and the suspension tests. Furthermore, the drying process of bacterial inoculum was less detrimental on skin than on glass surfaces. This study confirmed that the activity of a biocide tested in suspension or on an inanimate surface did not reflect its activity when tested on skin. Further development of the ex-vivo test may be useful, especially for testing the antimicrobial activity of formulations with antiseptic properties.

  6. A study of the human immune response to Lolium perenne (rye) pollen and its components, Lol p I and Lol p II (rye I and rye II). I. Prevalence of reactivity to the allergens and correlations among skin test, IgE antibody, and IgG antibody data.

    PubMed

    Freidhoff, L R; Ehrlich-Kautzky, E; Grant, J H; Meyers, D A; Marsh, D G

    1986-12-01

    In a stratified random sample of 320 white adults, the prevalence of puncture skin test positivity (ST +) to Lolium perenne (rye grass)-pollen extract (LPE) was 16%. Fifteen percent of all subjects (or 84% of subjects classified LPE IgE antibody positive [Ab +]) was classified IgE Ab + to highly purified Lol p I (Rye I), and 4% of all subjects (or 26% of subjects classified LPE IgE Ab +) was classified IgE Ab + to highly purified Lol p II (Rye II). These data and similar results obtained in an allergy-enriched group of 361 subjects are consistent with previous studies that Lol I is a major allergen and Lol II is a minor allergen of LPE. Whether we studied LPE, Lol I, or Lol II, responder subjects were younger than nonresponder subjects and more male than female subjects were responders. We then investigated the quantitative interrelationships among ST, IgE, and IgG Ab responsiveness to LPE, Lol I, and Lol II in the allergy-enriched group. For each allergen, log-log correlations were strong and significant for ST versus IgE Ab and for IgE Ab versus IgG Ab. All subjects IgE Ab + to Lol I or Lol II were IgG Ab + to that allergen, supporting other evidence for a commonality in the genetic control influencing the production of IgE and IgG Abs to a given allergen. Log-log correlations among ST end points, IgE Ab levels, or IgG Ab levels were strong for LPE versus either Lol I or Lol II but weak between Lol I and Lol II, consistent with the reported lack of cross-reactivity between Lol I and Lol II. Despite these findings, almost all Lol II + subjects were Lol I + by ST (98%), IgE Ab (91%), and IgG Ab (83%), suggesting that the Ia-restricted immune recognition of both these molecules is at least in part under a common genetic control.

  7. 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

  8. Plasmacytoid dendritic cells infiltrate the skin in positive tuberculin skin test indurations.

    PubMed

    Bond, Emily; Liang, Frank; Sandgren, Kerrie J; Smed-Sörensen, Anna; Bergman, Peter; Brighenti, Susanna; Adams, William C; Betemariam, Senait A; Rangaka, Molebogeng X; Lange, Christoph; Wilkinson, Robert J; Andersson, Jan; Loré, Karin

    2012-01-01

    Plasmacytoid dendritic cells (pDCs) are rarely present in normal skin but have been shown to infiltrate lesions of infections or autoimmune disorders. Here, we report that several DC subsets including CD123(+) BDCA-2/CD303(+) pDCs accumulate in the dermis in indurations induced by the tuberculin skin test (TST), used to screen immune sensitization by Mycobacterium tuberculosis. Although the purified protein derivate (PPD) used in the TST did not itself induce pDC recruitment or IFN-α production, the positive skin reactions showed high expression of the IFN-α-inducible protein MxA. In contrast, the local immune response to PPD was associated with substantial cell death and high expression of the cationic antimicrobial peptide LL37, which together can provide a means for pDC activation and IFN-α production. In vitro, pDCs showed low uptake of PPD compared with CD11c(+) and BDCA-3/CD141(+) myeloid DC subsets. Furthermore, supernatants from pDCs activated with LL37-DNA complexes reduced the high PPD uptake in myeloid DCs, as well as decreased their capacity to activate T-cell proliferation. Infiltrating pDCs in the TST reaction site may thus have a regulatory effect upon the antigen processing and presentation functions of surrounding potent myeloid DC subsets to limit potentially detrimental and excessive immune stimulation.

  9. 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.

  10. Use of in vitro testing to identify an unexpected skin sensitizing impurity in a commercial product: a case study.

    PubMed

    Natsch, Andreas; Gfeller, Hans; Emter, Roger; Ellis, Graham

    2010-03-01

    Due to regulatory constraints and ethical considerations, the quest for alternatives to animal testing has gained a new momentum. In general, animal welfare considerations and compliance with regulations are the key drivers for this research. Mechanistically based in vitro tests addressing specific toxicological questions can yield new information, for example on reactive components, and thus in certain cases the in vitro tests are not only second choice replacements of a 'gold standard' animal test but can also be used to develop safer products. Here we report a case study from the in vitro investigation on the commercial fragrance chemical Azurone. This compound was found to be a moderate skin sensitizer in the LLNA, whereas the structurally closely similar compound Calone is a non-sensitizer. A peptide reactivity assay indicated, that indeed Azurone yields peptide depletion, thus the in vitro assays confirmed the animal test result. LC-MS analysis of the peptide reactivity sample showed the presence of peptide adducts of unexpected molecular weight. They were consistent with the reaction of the peptide with a catechol related to Azurone. Detailed analytics indicated that indeed this catechol is present in the original batches as an impurity, but it has escaped quality control analysis, as it is not detectable in routine GC-analysis. A new purified batch was prepared, re-tested in the in vitro assays and predicted by the tests to be a non-sensitizer. A confirmatory LLNA test indeed yielded a significantly (10-fold) higher EC3 value of the new batch, but the LLNA was still positive. A dose-response study in the EpiSkin assay indicated that this molecule still has a significant skin irritation potential, which may generate the weak positive signal in the LLNA. This case study illustrates how the mechanistically based in vitro LC-MS peptide reactivity assay can be used to contribute to the understanding of the sensitization mechanism of a commercial product and help

  11. Skin sensitizers induce antioxidant response element dependent genes: application to the in vitro testing of the sensitization potential of chemicals.

    PubMed

    Natsch, Andreas; Emter, Roger

    2008-03-01

    Tests for skin sensitization are required prior to the market launch of new cosmetic ingredients and in vitro tests are needed to replace the current animal tests. Protein reactivity is the common feature of skin sensitizers and it is a crucial question whether a cellular in vitro assay can detect protein reactivity of diverse test chemicals. The signaling pathway involving the repressor protein Keap1 and the transcription factor nuclear factor-erythroid 2-related factor 2, which binds to the antioxidant response element (ARE) in the promoter of many phase II detoxification genes, is a potential cellular marker because Keap1 had been shown to be covalently modified by electrophiles which leads to activation of ARE-dependent genes. To evaluate whether this regulatory pathway can be used to develop a predictive cellular in vitro test for sensitization, 96 different chemicals of known skin sensitization potential were added to Hepa1C1C7 cells and the induction of the ARE-regulated quinone reductase (QR) activity was determined. In parallel, 102 chemicals were tested on the reporter cell line AREc32, which contains an eightfold repeat of the ARE sequence upstream of a luciferase gene. Among the strong/extreme skin sensitizers 14 out of 15 and 30 out of 34 moderate sensitizers induced the ARE-dependent luciferase activity and in many cases this response was paralleled by an induction of QR activity in Hepa1C1C7 cells. Sixty percent of the weak sensitizers also induced luciferase activity, and the overall accuracy of the assay was 83 percent. Only four of 30 tested nonsensitizers induced low levels of luciferase activity, indicating a high specificity of the assay. Thus, measurement of the induction of this signaling pathway provides an interesting in vitro test to screen for the skin sensitization potential of novel chemicals.

  12. 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.

  13. Comparative assessment of the acute skin irritation potential of detergent formulations using a novel human 4-h patch test method.

    PubMed

    Robinson, Michael K; Kruszewski, Francis H; Al-Atrash, Jenan; Blazka, Mark E; Gingell, Ralph; Heitfeld, Fred A; Mallon, David; Snyder, Neil K; Swanson, Judith E; Casterton, Phillip L

    2005-12-01

    Predictive skin irritation test methods, which do not require use of animals, are needed for the pre-market assessment of detergent formulations. The utility of a novel and ethical human acute skin irritation patch test method, originally developed for chemical skin irritation assessment, was evaluated. In this IRB-approved method, subjects were patched under occlusion for increasing periods of time up to 4h in duration. The total incidence of positive skin reactions for test products was compared to a positive control (20% aqueous sodium dodecyl sulfate [SDS]). Acutely irritating formulas were defined as those showing a significantly increased or equal incidence of positive responders compared with that of SDS. The time of exposure required for 50% of subjects to show a positive skin reaction (TR50 value) was calculated for each product and enabled test product comparisons within and between studies. Using this approach, 24 detergent formulations of various types were tested in seven individual studies. The skin irritation profiles were generally consistent within product types, which could be categorized as follows (by decreasing irritancy): mold/mildew removers (average TR50 = 0.37 h) > disinfectants/sanitizers (0.64 h) > fabric softener concentrate (1.09 h) = aluminum wash (1.20 h) > 20% SDS (1.81 h) > liquid laundry detergents (3.48 h) > liquid dish detergents (4.16 h) = liquid fabric softeners (4.56 h) = liquid hand soaps (4.58 h) = shampoos (5.40 h) = hard surface cleaners (6.34 h) > powder automatic dish detergents (>16 h) = powder laundry detergents (>16 h). In addition to formulation effects, some seasonal effects were noted; particularly greater winter-time reactivity to 20% SDS and the hard surface cleaner and liquid laundry formulations. These results demonstrate the utility of this patch test method for the comparative skin irritation assessment of these different product types.

  14. Skin Testing in the Evaluation and Management of Carboplatin-Related Hypersensitivity Reactions.

    PubMed

    Lax, Timothy; Long, Aidan; Banerji, Aleena

    2015-01-01

    Carboplatin-induced hypersensitivity reactions (HSRs) are a frequent occurrence in patients being retreated for malignancy. The most common and severe reactions are thought to be IgE mediated. Currently, skin testing is the only method used clinically to identify individuals sensitized to carboplatin. Despite almost 20 years of clinical use, a standardized approach to skin testing and its use in the management of carboplatin HSRs has not been well established. We review the utility of carboplatin skin testing and discuss factors that influence the interpretation of skin testing results. A risk stratification strategy using skin testing and desensitization to manage patients with carboplatin HSRs is proposed.

  15. Practical guide to skin prick tests in allergy to aeroallergens.

    PubMed

    Bousquet, J; Heinzerling, L; Bachert, C; Papadopoulos, N G; Bousquet, P J; Burney, P G; Canonica, G W; Carlsen, K H; Cox, L; Haahtela, T; Lodrup Carlsen, K C; Price, D; Samolinski, B; Simons, F E R; Wickman, M; Annesi-Maesano, I; Baena-Cagnani, C E; Bergmann, K C; Bindslev-Jensen, C; Casale, T B; Chiriac, A; Cruz, A A; Dubakiene, R; Durham, S R; Fokkens, W J; Gerth-van-Wijk, R; Kalayci, O; Kowalski, M L; Mari, A; Mullol, J; Nazamova-Baranova, L; O'Hehir, R E; Ohta, K; Panzner, P; Passalacqua, G; Ring, J; Rogala, B; Romano, A; Ryan, D; Schmid-Grendelmeier, P; Todo-Bom, A; Valenta, R; Woehrl, S; Yusuf, O M; Zuberbier, T; Demoly, P

    2012-01-01

    This pocket guide is the result of a consensus reached between members of the Global Allergy and Asthma European Network (GA(2) LEN) and Allergic Rhinitis and its Impact on Asthma (ARIA). The aim of the current pocket guide is to offer a comprehensive set of recommendations on the use of skin prick tests in allergic rhinitis-conjunctivitis and asthma in daily practice. This pocket guide is meant to give simple answers to the most frequent questions raised by practitioners in Europe, including 'practicing allergists', general practitioners and any other physicians with special interest in the management of allergic diseases. It is not a long or detailed scientific review of the topic. However, the recommendations in this pocket guide were compiled following an in-depth review of existing guidelines and publications, including the 1993 European Academy of Allergy and Clinical Immunology position paper, the 2001 ARIA document and the ARIA update 2008 (prepared in collaboration with GA(2) LEN). The recommendations cover skin test methodology and interpretation, allergen extracts to be used, as well as indications in a variety of settings including paediatrics and developing countries.

  16. Skin prick testing with standardized extracts from 3 different manufacturers. A comparative randomized study.

    PubMed

    Nielsen, N H; Dirksen, A; Mosbech, H; Launbjerg, J; Biering, I; Søborg, M

    1992-01-01

    The aim of this study was to compare skin reactivity to routine allergen prick test with panels of allergens, supplied by three different manufacturers. The allergens comprised ten aero-allergens commonly used for skin prick test in Northern Europe, and included pollen, dander, house dust mites, and moulds. Two hundred consecutive patients were tested. The methods for standardization of allergen extracts, declaration of allergenic potency, and recommended lancets differed. The equipment were Soluprick SQ (Allergologisk Laboratorium A/S, Denmark) (ALK), Alphatest (Dome/Hollister-Stier, U.K.) (DHS), and Phazet (Pharmacia, Sweden) (PHA). The coefficient of variation for the allergen coated PHA (same lancet was applied twice) was 0.31, and for ALK and DHS allergen extracts 0.13 and 0.18, respectively. The frequencies of patients with positive reactions to the various allergens were generally similar, although DHS appeared to elicit less positive reactions to Timothy, dog, and Dermatophagoides pteronnyssinus. For the individual physician, it may be important to know the allergenic activity of the different allergens in his routine panel compared to the activity in other similar panels.

  17. State of the art in non-animal approaches for skin sensitization testing: from individual test methods towards testing strategies.

    PubMed

    Ezendam, Janine; Braakhuis, Hedwig M; Vandebriel, Rob J

    2016-12-01

    The hazard assessment of skin sensitizers relies mainly on animal testing, but much progress is made in the development, validation and regulatory acceptance and implementation of non-animal predictive approaches. In this review, we provide an update on the available computational tools and animal-free test methods for the prediction of skin sensitization hazard. These individual test methods address mostly one mechanistic step of the process of skin sensitization induction. The adverse outcome pathway (AOP) for skin sensitization describes the key events (KEs) that lead to skin sensitization. In our review, we have clustered the available test methods according to the KE they inform: the molecular initiating event (MIE/KE1)-protein binding, KE2-keratinocyte activation, KE3-dendritic cell activation and KE4-T cell activation and proliferation. In recent years, most progress has been made in the development and validation of in vitro assays that address KE2 and KE3. No standardized in vitro assays for T cell activation are available; thus, KE4 cannot be measured in vitro. Three non-animal test methods, addressing either the MIE, KE2 or KE3, are accepted as OECD test guidelines, and this has accelerated the development of integrated or defined approaches for testing and assessment (e.g. testing strategies). The majority of these approaches are mechanism-based, since they combine results from multiple test methods and/or computational tools that address different KEs of the AOP to estimate skin sensitization potential and sometimes potency. Other approaches are based on statistical tools. Until now, eleven different testing strategies have been published, the majority using the same individual information sources. Our review shows that some of the defined approaches to testing and assessment are able to accurately predict skin sensitization hazard, sometimes even more accurate than the currently used animal test. A few defined approaches are developed to provide an

  18. 76 FR 77833 - Scientific Information Request on CYP2C19 Variants and Platelet Reactivity Tests

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-14

    ... Variants and Platelet Reactivity Tests AGENCY: Agency for Healthcare Research and Quality (AHRQ), HHS... platelet reactivity tests. Scientific information is being solicited to inform our Comparative... for studies that report on CYP2C19 variants and platelet reactivity tests, including those...

  19. Autologous serum and plasma skin test to predict 2-year outcome in chronic spontaneous urticaria

    PubMed Central

    Sangasapaviliya, Atik

    2016-01-01

    Background Autologous serum skin test (ASST) and autologous plasma skin test (APST) are simple methods to diagnose autoimmune chronic urticaria. However, the association data of ASST or APST with disease severity and long-term outcome are still unclear. Objective The results of ASST and APST might be used to predict urticaria symptom severity and long-term outcomes among chronic spontaneous urticaria (CSU) patients. Methods We evaluated the prevalence of reactive ASST and APST in 128 CSU patients. The patients were characterized by 4 groups: negative, ASST positive, APST positive, and both ASST and APST positive. We observed remission rate among the CSU patients during 2 years. Results Forty-four of 128 CSU patients (34%) had negative autologous skin test. The CSU patients with positive ASST, positive APST, and both positive ASST and APST were 47 (37%), 6 (5%), and 31 (24%), respectively. No significant difference was found between the groups according to urticaria severity score (USS) and dermatology life quality index (DLQI). Mean wheal diameter of ASST showed positive correlation with DLQI. Also, mean wheal diameter of APST showed positive correlation with USS and DLQI. Both the positive ASST and APST groups had a high proportion of 4-fold dose of H1-antihistamine than the positive ASST (p = 0.03) and negative groups (p = 0.0009). The rate of remission over 2 years in the negative, positive ASST, positive APST, and both positive ASST and APST groups were 81.1%, 62.3%, 60%, and 46.1%, respectively. The urticaria remission rate in patients in the negative group was significantly higher compared with both positive ASST and APST groups (odds ratio, 5.0; 95% confidence interval, 1.61–15.44; p = 0.006). Conclusion ASST and APST results could predict remission rates among patients with CSU. Our results suggested investigating ASST and APST among CSU patients before starting treatment. PMID:27803883

  20. 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...

  1. Low frequency of positive skin tests in asthmatic patients infected with Schistosoma mansoni exposed to high levels of mite allergens.

    PubMed

    Medeiros, Manoel; Almeida, Maria C; Figueiredo, Joanemile P; Atta, Ajax M; Mendes, Carlos M C; Araújo, Maria I; Taketomi, Ernesto A; Terra, Silvia A; Silva, Deise A O; Carvalho, Edgar M

    2004-04-01

    Helminthic infections and allergic diseases are highly prevalent in many parts of the world. Although skin reactivity to indoor allergens is decreased in subjects from helminthic endemic areas, the degree of exposure to mite allergens has not yet been investigated in these areas. This study evaluated the association between exposure to dust mites and skin reactivity to mite allergens in subjects with a history of wheezing in the last 12 months selected from a rural endemic area for schistosomiasis (group I, n = 21), and two non-Schistosoma mansoni endemic locale, a rural area (group II, n = 21) and a urban slum area (group III, n = 21). All subjects were evaluated by skin prick tests with mite allergens, and for total and specific immunoglobulin E (IgE) against dust mites, antibodies for S. mansoni, and for intestinal parasites. Dust samples from each subjects' home were quantified for mite allergen and species of the mite identification. Except for S. mansoni infection which was more prevalent in group I than in groups II and III (p < 0.0001), the prevalence of intestinal parasites, and total and specific IgE levels were similar for all groups. Despite the levels of mite allergens and specifically to Der p 1 detected in dust samples of subjects home from all three areas, the frequency of positive skin reactivity to mite antigens was significantly lower (19.0%) in subjects from group I relative to group II (76.2%) and group III (57.1%; p < 0.001). This result suggests that S. mansoni infection could modulate the immediate hypersensitivity skin response to mite allergens in highly exposed subjects.

  2. Xenobiotic metabolizing enzyme activities in cells used for testing skin sensitization in vitro.

    PubMed

    Fabian, E; Vogel, D; Blatz, V; Ramirez, T; Kolle, S; Eltze, T; van Ravenzwaay, B; Oesch, F; Landsiedel, R

    2013-09-01

    For ethical and regulatory reasons, in vitro tests for scoring potential toxicities of cosmetics are essential. A test strategy for investigating potential skin sensitization using two human keratinocytic and two human dendritic cell lines has been developed (Mehling et al. Arch Toxicol 86:1273–1295, 2012). Since prohaptens may be metabolically activated in the skin, information on xenobiotic metabolizing enzyme (XME) activities in these cell lines is of high interest. In this study, XME activity assays, monitoring metabolite or cofactor, showed the following: all three passages of keratinocytic (KeratinoSens® and LuSens) and dendritic (U937 und THP-1) cells displayed N-acetyltransferase 1 (NAT1) activities (about 6–60 nmol/min/mg S9-protein for acetylation of para-aminobenzoic acid). This is relevant since reactive species of many cosmetics are metabolically controlled by cutaneous NAT1. Esterase activities of about 1–4 nmol fluorescein diacetate/min/mg S9-protein were observed in all passages of investigated keratinocytic and about 1 nmol fluorescein diacetate/min/mg S9-protein in dendritic cell lines. This is also of practical relevance since many esters and amides are detoxified and others activated by cutaneous esterases. In both keratinocytic cell lines, activities of aldehyde dehydrogenase (ALDH) were observed (5–17 nmol product/min/mg cytosolic protein). ALDH is relevant for the detoxication of reactive aldehydes. Activities of several other XME were below detection, namely the investigated cytochrome P450-dependent alkylresorufin O-dealkylases 7-ethylresorufin O-deethylase, 7-benzylresorufin O-debenzylase and 7-pentylresorufin O-depentylase (while NADPH cytochrome c reductase activities were much above the limit of quantification), the flavin-containing monooxygenase, the alcohol dehydrogenase as well as the UDP glucuronosyl transferase activities.

  3. Clinical patterns and results of radioallergosorbent test (RAST) and skin tests in penicillin allergy.

    PubMed

    Kraft, D; Wide, L

    1976-06-01

    Seventy-nine patients with acute or former reactions to penicillin were investigated by a benzylpenicilloyl (BPO)-specific RAST and/or by skin tests with penicilloyl-polylysine (PPL), benzylpenicillin and penicilloic acid and the results were correlated with the different clinical pictures. Positive RAST and skin test results could be found in patients with anaphylactic shock, urticaria and serum sickness-like reaction and sometimes in a special group of exanthems, which are characterized by the existence of many different lesions at the same time, therefore called 'polymorphic exanthems', and often observed after high-dosage penicillin therapy. In cases of scarlatiniform or morbilliform exanthems no positive results were found. The BPO-specific RAST showed an overall correlation of 95-I% with skin tests using PPL. However, some patients with positive skin tests to benzylpenicillin and penicilloic acid did no have detectable circulating IgE antibodies to BPO. This emphasizes the need for including these antigens in in vitro methods. The RAST was informative even at the allergic reaction or in the first 15 days afterwards and seems to be very valuable for early diagnosis of penicillin allergy especially in cases when many drugs have been given.

  4. 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

  5. arNOX: generator of reactive oxygen species in the skin and sera of aging individuals subject to external modulation.

    PubMed

    Morré, Dorothy M; Meadows, Christiaan; Morré, D James

    2010-01-01

    An aging-related cell-surface oxidase (aging-related NADH oxidase, arNOX) generating superoxide and other reactive oxygen species is shed from the cell surface and is found in saliva, urine, perspiration, and interstitial fluids that surround the collagen and elastin matrix underlying dermis. arNOX activity correlates with age and reaches a maximum at about age 65 in males and 55 in females. arNOX activities are highly correlated with values of human skin where a causal relationship is indicated. Ongoing efforts focus on cloning arNOX proteins and development of antiaging formulas based on arNOX inhibition (intervention).

  6. A cross-reactive antigen of thymus and skin epithelial cells common with the polysaccharide of group A streptococci.

    PubMed

    Lyampert, I M; Beletskaya, L V; Borodiyuk, N A; Gnezditskaya, E V; Rassokhina, I I; Danilova, T A

    1976-07-01

    Investigation of antibodies to the specific determinant of streptococcal group A polysaccharide in indirect immunofluorescence experiments has revealed the existence of a cross-reactive antigen in the epithelial cells of the thymus and skin. This CR antigen is contained by the epithelial cells of man and animals of different species. It has been demonstrated in all the individuals studied including animals producing antibodies to the polysaccharide of Group A streptococci. The principal cause of autoimmune thymitis characteristic of rheumatic fever and other autoimmune processes is probably damage done to the thymus by autoantibodies resulting from immunization with microbial cross-reactive antigens shared by the thymus. Reaction of the autoantibodies with thymic antigens may affect the immunosuppressive function of the thymus and the maturation process of suppressor T cells. These events probably constitute the basic stage in the development of an autoimmune process.

  7. 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.

  8. Sensations of skin infestation linked to abnormal frontolimbic brain reactivity and differences in self-representation.

    PubMed

    Eccles, J A; Garfinkel, S N; Harrison, N A; Ward, J; Taylor, R E; Bewley, A P; Critchley, H D

    2015-10-01

    Some patients experience skin sensations of infestation and contamination that are elusive to proximate dermatological explanation. We undertook a functional magnetic resonance imaging study of the brain to demonstrate, for the first time, that central processing of infestation-relevant stimuli is altered in patients with such abnormal skin sensations. We show differences in neural activity within amygdala, insula, middle temporal lobe and frontal cortices. Patients also demonstrated altered measures of self-representation, with poorer sensitivity to internal bodily (interoceptive) signals and greater susceptibility to take on an illusion of body ownership: the rubber hand illusion. Together, these findings highlight a potential model for the maintenance of abnormal skin sensations, encompassing heightened threat processing within amygdala, increased salience of skin representations within insula and compromised prefrontal capacity for self-regulation and appraisal.

  9. The Return of Delayed-Type Hypersensitivity Skin Testing for Coccidioidomycosis.

    PubMed

    Wack, Elizabeth E; Ampel, Neil M; Sunenshine, Rebecca H; Galgiani, John N

    2015-09-01

    A skin test that detects dermal hypersensitivity in persons with past infection with Coccidioides species is again available for clinical use. Nearly all of the clinical studies with similar materials were published prior to the 1990s, and as a result, many practicing physicians will be unfamiliar with how skin testing for coccidioidomycosis might be useful in patient management or as a research tool. We review clinical and epidemiological studies with past skin test antigens, the composition of past and current skin test preparations with particular attention to differences in the preservatives, and how the current preparation could be used today.

  10. Fractionation and Composition Studies of Skin Test-Active Components of Sensitins from Coccidioides immitis

    PubMed Central

    Anderson, Kenneth L.; Wheat, Robert W.; Conant, Norman F.

    1971-01-01

    Coccidioidin skin-test activities from mycelial culture filtrates and autolysates were partially purified. Major chemical constituents included 3-O-methylmannose, mannose, and amino acids. PMID:5119201

  11. pH changes in the dermis during the course of the tuberculin skin test.

    PubMed Central

    Harrison, D K; Spence, V A; Beck, J S; Lowe, J G; Walker, W F

    1986-01-01

    The response of six healthy young adults to tuberculin skin testing was studied. Five subjects developed a typical delayed-type hypersensitivity reaction to PPD with a local rise in skin temperature, and the sixth showed a less intense response; a considerable increase in blood flow velocity was seen in all reactions. All subjects showed a fall in pH in the dermis during the course of the reaction: in four subjects the pH minimum occurred at the time when the changes of erythema and induration were most prominent, in one subject the pH fall preceded the maximal clinical changes, and in the remaining subject a substantial fall in pH occurred with only transient erythema. It was concluded that the local tissue acidosis had resulted from the greatly increased metabolic demand of the lymphocytes and monocytes attracted into the dermis as part of the type IV delayed-type hypersensitivity reaction, and that the concurrent reactive hyperaemia was insufficient to clear the acidic metabolic products of the greatly increased cell population. Images Figure 1 PMID:3804375

  12. 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

  13. Test results of chemical reactivity test (CRT) analysis of structural materials and explosives

    SciTech Connect

    Back, P.S.; Barnhart, B.V.; Walters, R.R.; Haws, L.D.; Collins, L.W.

    1980-03-21

    The chemical reactivity test, CRT, is a procedure used to screen the compatibility of component structure materials with explosives. This report contains the results of CRT materials evaluations conducted at Mound Facility. Data about materials combinations are catalogued both under the name of the explosive and the nonexplosive.

  14. 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.

  15. Skin Corrosion and Irritation Test of Nanoparticles Using Reconstructed Three-Dimensional Human Skin Model, EpiDermTM

    PubMed Central

    Kim, Hyejin; Choi, Jonghye; Lee, Handule; Park, Juyoung; Yoon, Byung-Il; Jin, Seon Mi; Park, Kwangsik

    2016-01-01

    Effects of nanoparticles (NPs) on skin corrosion and irritation using three-dimensional human skin models were investigated based on the test guidelines of Organization for Economic Co-operation and Development (OECD TG431 and TG439). EpiDermTM skin was incubated with NPs including those harboring iron (FeNPs), aluminum oxide (AlNPs), titanium oxide (TNPs), and silver (AgNPs) for a defined time according to the test guidelines. Cell viabilities of EpiDermTM skins were measured by the 3-(4, 5-dimethylthi-azol-2-yl)-2.5-diphenyltetrazolium bromide based method. FeNPs, AlNPs, TNPs, and AgNPs were non-corrosive because the viability was more than 50% after 3 min exposure and more than 15% after 60 min exposure, which are the non-corrosive criteria. All NPs were also non-irritants, based on viability exceeding 50% after 60 min exposure and 42 hr post-incubation. Release of interleukin 1-alpha and histopathological analysis supported the cell viability results. These findings suggest that FeNPs, AlNPs, TNPs, and AgNPs are ‘non-corrosive’ and ‘non-irritant’ to human skin by a globally harmonized classification system. PMID:27818733

  16. Cross-reactivity in Cryptococcus antigen latex agglutination test in two commercial kits.

    PubMed

    Tone, Kazuya; Umeda, Yoshiko; Makimura, Koichi

    2016-05-01

    This article presents an examination of the cross-reactivity of pathogenic fungi with Cryptococcus neoformans in two commercial Cryptococcus antigen latex agglutination tests performed across 39 fungal strains. Some fungi were newly indicated as Cryptococcus cross-reactive, and the two kits showed differences in cross-reactive fungi.

  17. Skin models for the testing of transdermal drugs

    PubMed Central

    Abd, Eman; Yousef, Shereen A; Pastore, Michael N; Telaprolu, Krishna; Mohammed, Yousuf H; Namjoshi, Sarika; Grice, Jeffrey E; Roberts, Michael S

    2016-01-01

    The assessment of percutaneous permeation of molecules is a key step in the evaluation of dermal or transdermal delivery systems. If the drugs are intended for delivery to humans, the most appropriate setting in which to do the assessment is the in vivo human. However, this may not be possible for ethical, practical, or economic reasons, particularly in the early phases of development. It is thus necessary to find alternative methods using accessible and reproducible surrogates for in vivo human skin. A range of models has been developed, including ex vivo human skin, usually obtained from cadavers or plastic surgery patients, ex vivo animal skin, and artificial or reconstructed skin models. Increasingly, largely driven by regulatory authorities and industry, there is a focus on developing standardized techniques and protocols. With this comes the need to demonstrate that the surrogate models produce results that correlate with those from in vivo human studies and that they can be used to show bioequivalence of different topical products. This review discusses the alternative skin models that have been developed as surrogates for normal and diseased skin and examines the concepts of using model systems for in vitro–in vivo correlation and the demonstration of bioequivalence. PMID:27799831

  18. Allergy to betalactam antibiotics in children: results of a 20-year study based on clinical history, skin and challenge tests.

    PubMed

    Ponvert, C; Perrin, Y; Bados-Albiero, A; Le Bourgeois, M; Karila, C; Delacourt, C; Scheinmann, P; De Blic, J

    2011-06-01

    Studies based on skin and challenge tests have shown that 12-60% of children with suspected betalactam hypersensitivity were allergic to betalactams. Responses in skin and challenge tests were studied in 1865 children with suspected betalactam allergy (i) to confirm or rule out the suspected diagnosis; (ii) to evaluate diagnostic value of immediate and non-immediate responses in skin and challenge tests; (iii) to determine frequency of betalactam allergy in those children, and (iv) to determine potential risk factors for betalactam allergy. The work-up was completed in 1431 children, of whom 227 (15.9%) were diagnosed allergic to betalactams. Betalactam hypersensitivity was diagnosed in 50 of the 162 (30.9%) children reporting immediate reactions and in 177 of the 1087 (16.7%) children reporting non-immediate reactions (p<0.001). The likelihood of betalactam hypersensitivity was also significantly higher in children reporting anaphylaxis, serum sickness-like reactions, and (potentially) severe skin reactions such as acute generalized exanthematic pustulosis, Stevens-Johnson syndrome, and drug reaction with systemic symptoms than in other children (p<0.001). Skin tests diagnosed 86% of immediate and 31.6% of non-immediate sensitizations. Cross-reactivity and/or cosensitization among betalactams was diagnosed in 76% and 14.7% of the children with immediate and non-immediate hypersensitivity, respectively. The number of children diagnosed allergic to betalactams decreased with time between the reaction and the work-up, probably because the majority of children with severe and worrying reactions were referred for allergological work-up more promptly than the other children. Sex, age, and atopy were not risk factors for betalactam hypersensitivity. In conclusion, we confirm in numerous children that (i) only a few children with suspected betalactam hypersensitivity are allergic to betalactams; (ii) the likelihood of betalactam allergy increases with earliness and

  19. Development of Cutaneous Leishmaniasis after Leishmania Skin Test

    PubMed Central

    Machado, Paulo R.; Carvalho, Augusto M.; Machado, Gustavo U.; Dantas, Marina L.; Arruda, Sérgio

    2011-01-01

    Thirty-year-old female with a previous history of a cutaneous ulcer suspicious of leishmaniasis 20 years ago presented with a new complaint of a depressed papular lesion 8 × 7 mm in the right lower extremity. The lesion was of 10-day duration. Because early cutaneous leishmaniasis (CL) lesions may have a non-ulcerated appearance, a Leishmania skin test (LST) was performed on the forearm with a strong positive result (38 × 32 mm). After 8 days, the lesion in the leg, which was diagnosed as folliculitis, completely healed. However, a typical CL ulcer (26 × 24 mm) developed at the LST site. Histopathology of the new lesion did not identifiy parasites, but the findings were consistent with a diagnosis of CL. Further analysis identified amastigotes by immunohistochemical stain. Mononuclear cells harvested from the patient were stimulated with Leishmania antigen and showed high levels of production of both tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ): 2,943 pg/mL and 2,313 pg/mL, respectively. After 40 days of treatment with antimony and pentoxifylline, the ulcer resolved. The development of CL at the LST site suggests a strong Th1 immune response, and it is an in vivo documentation of the role of the host immune response in the pathology of CL. It teaches us that LST should be cautiously, if at all, used in patients with self-healing CL ulcers. PMID:22162702

  20. Development of cutaneous leishmaniasis after leishmania skin test.

    PubMed

    Machado, Paulo R; Carvalho, Augusto M; Machado, Gustavo U; Dantas, Marina L; Arruda, Sérgio

    2011-01-01

    Thirty-year-old female with a previous history of a cutaneous ulcer suspicious of leishmaniasis 20 years ago presented with a new complaint of a depressed papular lesion 8 × 7 mm in the right lower extremity. The lesion was of 10-day duration. Because early cutaneous leishmaniasis (CL) lesions may have a non-ulcerated appearance, a Leishmania skin test (LST) was performed on the forearm with a strong positive result (38 × 32 mm). After 8 days, the lesion in the leg, which was diagnosed as folliculitis, completely healed. However, a typical CL ulcer (26 × 24 mm) developed at the LST site. Histopathology of the new lesion did not identifiy parasites, but the findings were consistent with a diagnosis of CL. Further analysis identified amastigotes by immunohistochemical stain. Mononuclear cells harvested from the patient were stimulated with Leishmania antigen and showed high levels of production of both tumor necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ): 2,943 pg/mL and 2,313 pg/mL, respectively. After 40 days of treatment with antimony and pentoxifylline, the ulcer resolved. The development of CL at the LST site suggests a strong Th1 immune response, and it is an in vivo documentation of the role of the host immune response in the pathology of CL. It teaches us that LST should be cautiously, if at all, used in patients with self-healing CL ulcers.

  1. Insertion Testing of Polyethylene Glycol Microneedle Array into Cultured Human Skin with Biaxial Tension

    NASA Astrophysics Data System (ADS)

    Takano, Naoki; Tachikawa, Hiroto; Miyano, Takaya; Nishiyabu, Kazuaki

    Aiming at the practical use of polyethylene glycol (PEG) microneedles for transdermal drug delivery system (DDS), a testing apparatus for their insertion into cultured human skin has been developed. To simulate the variety of conditions of human skin, biaxial tension can be applied to the cultured human skin. An adopted testing scheme to apply and control the biaxial tension is similar to the deep-draw forming technique. An attention was also paid to the short-time setup of small, thin and wet cultured skin. One dimensional array with four needles was inserted and influence of tension was discussed. It was found that tension, deflection of skin during insertion and original curvature of skin are the important parameters for microneedles array design.

  2. 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

  3. Multiple skin testing of Kenyan schoolchildren with a series of new tuberculins.

    PubMed Central

    Paul, R. C.; Stanford, J. L.; Misljenóvic, O.; Lefering, J.

    1975-01-01

    This study on Kenyan schoolchildren aims to elucidate the effect of contact with environmental mycobacteria on the development of specific delayed hypersensitivity. A series of 12 skin test reagents was employed; eleven of them were prepared from extracts of living mycobacteria and the last was the P.P.D. RT 23. Eight of the new tuberculins were prepared from mycobacteria recovered from the East African environment. A total of 8641 tests were carried out on 4320 children between the ages of 6 and 17 years in four townships. Two of these townships were in fertile agricultural areas and two were in the desert. Just over 80% of the children had received BCG immunization The results obtained showed that increasing age, geographical locality and BCG immunization all had a profound effect, and socioeconomic background had some effect, on the pattern of reactivity to the various reagents. The rationale behind the use of the series of new tuberculins and the results obtained with them are discussed in relation to the interacting effects of the factors complicating these results. PMID:1058246

  4. 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

  5. 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.

  6. 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.

  7. Skin and radioallergosorbent tests in patients with sensitivity to bee and wasp venom.

    PubMed

    Harries, M G; Kemeny, D M; Youlten, L J; Mills, M M; Lessof, M H

    1984-09-01

    Intradermal (ID) and prick tests with bee or wasp venom (Pharmalgen) have been performed on 102 subjects with a history of adverse reactions to stings and forty-six control subjects giving no such history. Venom was diluted 100, 10 and 1 microgram/ml for prick testing and 10(-2), 10(-2), 10(-3) and 10(-4) micrograms/ml for ID injections. In forty-six control subjects all were tested with the highest concentration of prick testing solution (100 micrograms/ml), eight (17%) had positive reactions, a similar reaction rate to that reported in control subjects using 10(-1) micrograms/ml ID. In our 102 test subjects skin tests were therefore regarded as positive only if the reaction was elicited by 10 micrograms/ml or less by prick test of 10(-2) micrograms/ml or less ID. In general the results with skin prick tests and ID tests were comparable when the prick solution was 1000 times the concentration of that used for ID testing. ID tests were positive in thirteen with negative skin prick, seven of whom had detectable antibodies when tested by RAST. Conversely four with a positive skin prick test (two of whom were RAST positive) were considered negative on ID testing. As judged either by RAST or skin tests it appeared that sensitivity diminished with the time interval from the last sting (P less than 0.001).

  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. 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.

  10. 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.

  11. The role of skin conductance level reactivity in the impact of children's exposure to interparental conflict on their attention performance.

    PubMed

    Zemp, Martina; Bodenmann, Guy; Mark Cummings, E

    2014-02-01

    Previous research suggests that undermining of attention performance might be one decisive underlying mechanism in the link between marital conflict and children's academic maladjustment, but little is known about specific risk patterns in this regard. This study examines, in an experimental approach, the role of children's history of interparental discord and skin conductance level reactivity (SCLR) as moderators in the link between analogue marital conflict exposure and children's attention. The attention performance of 57 children, aged 11 to 13 years, was assessed prior to and immediately after a 1-min video exposure to either (a) a couple conflict or (b) a neutral condition. SCLR was measured continuously throughout the stimulus presentation. Results indicated that children's family background of interparental conflict and their physiological reactivity moderated the influence of the experimental stimulus on children's short-term attention performance. Lower SCLR served as a protective factor in children from high-conflict homes exposed to the couple conflict. The current study advances the body of knowledge in this field by identifying risk patterns for the development of attention problems in children in relation to marital conflict exposure.

  12. 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.

  13. Tuberculosis screening and compliance with return for skin test reading among active drug users.

    PubMed Central

    Malotte, C K; Rhodes, F; Mais, K E

    1998-01-01

    OBJECTIVES: This study assessed the independent and combined effects of different levels of monetary incentives and a theory-based educational intervention on return for tuberculosis (TB) skin test reading in a sample of active injection drug and crack cocaine users. Prevalence of TB infection in this sample was also determined. METHODS: Active or recent drug users (n = 1004), recruited via street outreach techniques, were skin tested for TB. They were randomly assigned to 1 of 2 levels of monetary incentive ($5 and $10) provided at return for skin test reading, alone or in combination with a brief motivational education session. RESULTS: More than 90% of those who received $10 returned for skin test reading, in comparison with 85% of those who received $5 and 33% of those who received no monetary incentive. The education session had no impact on return for skin test reading. The prevalence of a positive tuberculin test was 18.3%. CONCLUSIONS: Monetary incentives dramatically increase the return rate for TB skin test reading among drug users who are at high risk of TB infection. PMID:9585747

  14. Tuberculin skin test conversion among health sciences students: A retrospective cohort study

    PubMed Central

    Pérez-Lu, José E.; Cárcamo, Cesar P.; García, Patricia J.; Bussalleu, Alejandro; Bernabé-Ortiz, Antonio

    2014-01-01

    SUMMARY Previous studies have reported that health sciences students are at greater risk for tuberculosis infection, especially in developing countries. The objective of this study was to estimate the prevalence, incidence, and factors associated with latent tuberculosis infection among Health Sciences students in Peru. Students enrolled at private university (in Lima – Peru) are tested annually for tuberculosis infection by tuberculin skin test. Data on tuberculin skin test results between 2002 and 2009 was used in this retrospective cohort study, a total of 4842 students were included. Tuberculin skin test conversion was defined as the change of tuberculin skin test from negative (<10 mm) to positive (≥10 mm) after 48 –72 h of inoculation. Baseline tuberculin skin test positivity was 1.0% (95%CI: 0.6%–1.3%), whereas tuberculin skin test conversion incidence was 12.4 per 100 person-years (95%CI: 11.8–13.0). This study showed that students from clinical careers in close contact with patients had an increased risk of tuberculosis infection in the internship, especially Medicine, Dentistry, Medical Technology and Nursing. Administrative, environmental and personal protection measures should be implemented and evaluated periodically in order to reduce the risk of exposure. PMID:23116653

  15. 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…)

  16. Evaluation of antibiotic allergy: the role of skin tests and drug challenges.

    PubMed

    Solensky, Roland; Khan, David A

    2014-09-01

    Antibiotic allergies are frequently reported in both adult and pediatric populations. While a detailed drug history is essential in the evaluation of antibiotic allergy, the history is typically insufficient to determine the presence of a drug allergy. The most readily available diagnostic testing for evaluating antibiotic allergies are drug skin testing and drug challenges. This review will focus on updates in the evaluation of antibiotic allergy utilizing immediate skin tests, delayed intradermal testing, drug patch tests, and drug challenges for both adults and children with histories of antibiotic allergies.

  17. 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

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

    PubMed

    Sharma, Rakesh

    2010-07-21

    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.

  19. 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.

  20. 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.

  1. Suitability of skin integrity tests for dermal absorption studies in vitro.

    PubMed

    Guth, Katharina; Schäfer-Korting, Monika; Fabian, Eric; Landsiedel, Robert; van Ravenzwaay, Ben

    2015-02-01

    Skin absorption testing in vitro is a regulatory accepted alternative method (OECD Guideline 428). Different tests can be applied to evaluate the integrity of the skin samples. Here, we compared the pre- or post-run integrity tests (transepidermal electrical resistance, TEER; transepidermal water loss, TEWL; absorption of the reference compounds water, TWF, or methylene blue, BLUE) and additionally focused on co-absorption of a (3)H-labeled internal reference standard (ISTD) as integrity parameter. The results were correlated to absorption profiles of various test compounds. Limit values of 2kΩ, 10 gm(-2)h(-1) and 4.5∗10(-3)cmh(-1) for the standard methods TEER, TEWL and TWF, respectively, allowed distinguishing between impaired and intact human skin samples in general. Single skin samples did, however, not, poorly and even inversely correlate with the test-compound absorption. In contrast, results with ISTD (e.g. (3)H-testosterone) were highly correlated to the absorption of (14)C-labeled test compounds. Importantly, ISTD did not influence analytics or absorption of test compounds. Therefore, ISTD, especially when adjusted to the physico-chemical properties of test compounds, is a promising concept to assess the integrity of skin samples during the whole course of absorption experiments. However, a historical control dataset is yet necessary for a potential routine application.

  2. Outcome of asbestos exposure (lung fibrosis and antinuclear antibodies) with respect to skin reactivity: an 8-year longitudinal study

    SciTech Connect

    Lange, A.; Garncarek, D.; Tomeczko, J.; Ciechanowski, G.; Bisikiewicz, R.

    1986-10-01

    Two hundred seventy asbestos workers were examined during an 8-year period. During this time five consecutive surveys were completed. Skin tests with streptokinase-streptodornase (SK-SD), tuberculin (PPD), and phytohemagglutinin (PHA) were performed in the middle of this period. The results of these tests were related to X-ray chest film results and the appearance of antinuclear antibodies (ANA). In all surveys, except the first, X-ray films with small irregular opacities with a profusion greater than or equal to1/1 belonged more frequently to asbestos workers who did not respond to SK-SD or PHA. Thirty-one cases of asbestosis were diagnosed at that time, 23 of them became asbestotic after the skin tests were performed. Asbestotic cases contributed more frequently to the group with energy as compared to asbestos workers lacking asbestosis. Furthermore, asbestosis was correlated with lack of response to second strength of SK-SD in males and PHA in both sexes. Lack of response to these activators was predictive of asbestosis. Asbestos workers with ANA frequently displayed a lack of response to the first strength of SK-SD, PPD, and PHA. This was partly due to the presence of asbestotic cases in the group. However, low responders to all these activators were found frequently in the group with ANA independent of the presence of asbestosis.

  3. 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,…

  4. 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

    ... 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 Guidelines... ``Product Performance of Skin-applied Insect Repellents of Insects and Other Arthropods'' (OPPTS...

  5. Skin-prick tests for hypersensitivity to alpha-amylase preparations.

    PubMed

    Moneo, I; Alday, E; Sanchez-Agudo, L; Curiel, G; Lucena, R; Calatrava, J M

    1995-06-01

    Twenty-five asthmatic subjects with suspected alpha-amylase hypersensitivity were studied by skin-prick tests, a capture ELISA, immunoblotting and bronchial provocation tests. At the same time, different amylases were analysed by SDS-PAGE and immunoblotting using a polyclonal rabbit antiserum. Eight patients showed a positive bronchial response to amylase. Seven of them had positive skin-prick tests, with this method being the most sensitive approach for diagnosis. However, in four cases, skin tests were also positive although the patients had a negative provocation test, thus demonstrating that skin tests are not specific. ELISA and blotting showed similar results in terms of sensitivity and specificity. The enzymes used by the workers included several antigens besides alpha-amylase. The rabbit antiserum to alpha-amylase detected a protein in a wheat flour extract. In one case, the IgE antibodies were specific only for a contaminant of lower molecular weight than amylase. These facts suggest that proteins from the culture medium could be responsible for some cases of amylase hypersensitivity, making the diagnosis difficult. The presence of amylase in another enzymatic extract, a protease produced by Aspergillus oryzae, was proved by means of skin tests and immunoblotting, thus demonstrating the allergenic properties of this enzymatic preparation.

  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.

  8. 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

  9. The potential utility of iodinated contrast media (ICM) skin testing in patients with ICM hypersensitivity.

    PubMed

    Ahn, Young-Hwan; Koh, Young-Il; Kim, Joo-Hee; Ban, Ga-Young; Lee, Yeon-Kyung; Hong, Ga-Na; Jin, U-Ram; Choi, Byung-Joo; Shin, Yoo-Seob; Park, Hae-Sim; Ye, Young-Min

    2015-03-01

    Both immediate and delayed hypersensitivity reactions to iodinated contrast media (ICM) are relatively common. However, there are few data to determine the clinical utility of immunologic evaluation of ICM. To evaluate the utility of ICM skin testing in patients with ICM hypersensitivity, 23 patients (17 immediate and 6 delayed reactions) were enrolled from 3 university hospitals in Korea. With 6 commonly used ICM including iopromide, iohexol, ioversol, iomeprol, iopamidol and iodixanol, skin prick (SPT), intradermal (IDT) and patch tests were performed. Of 10 patients with anaphylaxis, 3 (30.0%) and 6 (60.0%) were positive respectively on SPTs and IDTs with the culprit ICM. Three of 6 patients with urticaria showed positive IDTs. In total, 11 (64.7%) had positive on either SPT or IDT. Three of 6 patients with delayed rashes had positive response to patch test and/or delayed IDT. Among 5 patients (3 anaphylaxis, 1 urticaria and 1 delayed rash) taken subsequent radiological examinations, 3 patients administered safe alternatives according to the results of skin testing had no adverse reaction. However, anaphylaxis developed in the other 2 patients administered the culprit ICM again. With 64.7% (11/17) and 50% (3/6) of the sensitivities of corresponding allergic skin tests with culprit ICM for immediate and delayed hypersensitivity reactions, the present study suggests that skin tests is useful for the diagnosis of ICM hypersensitivity and for selecting safe ICM and preventing a recurrence of anaphylaxis caused by the same ICM.

  10. 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."

  11. Safety and Efficacy Assessment of Two New Leprosy Skin Test Antigens: Randomized Double Blind Clinical Study

    PubMed Central

    Rivoire, Becky L.; Groathouse, Nathan A.; TerLouw, Stephen; Neupane, Kapil Dev; Ranjit, Chaman; Sapkota, Bishwa Raj; Khadge, Saraswoti; Kunwar, Chatra B.; Macdonald, Murdo; Hawksworth, Rachel; Thapa, Min B.; Hagge, Deanna A.; Tibbals, Melinda; Smith, Carol; Dube, Tina; She, Dewei; Wolff, Mark; Zhou, Eric; Makhene, Mamodikoe; Mason, Robin; Sizemore, Christine; Brennan, Patrick J.

    2014-01-01

    showed lower specificity (70% and 60%) and sensitivity (10% and 15%). BL/LL leprosy patients were anergic to the leprosy antigens. Interpretation MLSA-LAM and MLCwA at both high (1.0 µg) and low (0.1 µg) doses were found to be safe for use in humans without known exposure to leprosy and in target populations. At a sensitivity rate of 20–25% these antigens are not suitable as a skin test for the detection of the early stages of leprosy infection; however, the degree of specificity is impressive given the presence of cross-reactive antigens in these complex native M. leprae preparations. Trial Registration ClinicalTrails.gov NCT01920750 (Phase I), NCT00128193 (Phase II) PMID:24874401

  12. [Anaphylactic reaction caused by the performance of skin tests: report of a case].

    PubMed

    Eleuterio González, J; Leal de Hernández, L; González Spencer, D

    1997-01-01

    A case of anaphylaxis following skin tests for airborne allergens in a 25-year-old female patient diagnosed with bronchial asthma and allergic rhinitis, is presented. The purpose of this paper is to alert against severe systemic reactions related to skin tests. The reaction occurred 15 minutes after administration of various airborne allergens (pollens, air molds, and house dust), and the symptoms were: hypogastric pain, transvaginal bleeding, generalized urticaria, and bronchospasm. Immediate treatment consisted of antihistamines, bronchodilatators and steroids; the symptoms subsided in 12 hours. We conclude that skin testing can give rise to severe systemic reactions which should be identified and treated immediately by trained physicians and ancillary personnel, and that these tests should be avoided when pregnancy is suspected.

  13. 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.

  14. Use of genotoxicity information in the development of integrated testing strategies (ITS) for skin sensitization.

    PubMed

    Mekenyan, Ovanes; Patlewicz, Grace; Dimitrova, Gergana; Kuseva, Chanita; Todorov, Milen; Stoeva, Stoyanka; Kotov, Stefan; Donner, E Maria

    2010-10-18

    Skin sensitization is an end point of concern for various legislation in the EU, including the seventh Amendment to the Cosmetics Directive and Registration Evaluation, Authorisation and Restriction of Chemicals (REACH). Since animal testing is a last resort for REACH or banned (from 2013 onward) for the Cosmetics Directive, the use of intelligent/integrated testing strategies (ITS) as an efficient means of gathering necessary information from alternative sources (e.g., in vitro, (Q)SARs, etc.) is gaining widespread interest. Previous studies have explored correlations between mutagenicity data and skin sensitization data as a means of exploiting information from surrogate end points. The work here compares the underlying chemical mechanisms for mutagenicity and skin sensitization in an effort to evaluate the role mutagenicity information can play as a predictor of skin sensitization potential. The Tissue Metabolism Simulator (TIMES) hybrid expert system was used to compare chemical mechanisms of both end points since it houses a comprehensive set of established structure-activity relationships for both skin sensitization and mutagenicity. The evaluation demonstrated that there is a great deal of overlap between skin sensitization and mutagenicity structural alerts and their underlying chemical mechanisms. The similarities and differences in chemical mechanisms are discussed in light of available experimental data. A number of new alerts for mutagenicity were also postulated for inclusion into TIMES. The results presented show that mutagenicity information can provide useful insights on skin sensitization potential as part of an ITS and should be considered prior to any in vivo skin sensitization testing being initiated.

  15. 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.

  16. Evaluation of carotenoids and reactive oxygen species in human skin after UV irradiation: a critical comparison between in vivo and ex vivo investigations.

    PubMed

    Meinke, Martina C; Müller, Robert; Bechtel, Anne; Haag, Stefan F; Darvin, Maxim E; Lohan, Silke B; Ismaeel, Fakher; Lademann, Jürgen

    2015-03-01

    UV irradiation is one of the most harmful exogenous factors for the human skin. In addition to the development of erythema, free radicals, that is reactive oxygen species (ROS), are induced under its influence and promote the development of oxidative stress in the skin. Several techniques are available for determining the effect of UV irradiation. Resonance Raman spectroscopy (RRS) measures the reduction of the carotenoid concentration, while electron paramagnetic resonance (EPR) spectroscopy enables the analysis of the production of free radicals. Depending on the method, the skin parameters are analysed in vivo or ex vivo. This study provides a critical comparison between in vivo and ex vivo investigations on the ROS formation and carotenoid depletion caused by UV irradiation in human skin. The oxygen content of tissue was also determined. It was shown that the antioxidant status measured in the skin samples in vivo and ex vivo was different. The depletion in the carotenoid concentration in vivo exceeded the value determined ex vivo by a factor of about 1.5, and the radical formation after UV irradiation was significantly greater in vivo by a factor of 3.5 than that measured in excised human skin, which can be explained by the lack of oxygen ex vivo.

  17. The Phenion full-thickness skin model for percutaneous absorption testing.

    PubMed

    Ackermann, K; Borgia, S Lombardi; Korting, H C; Mewes, K R; Schäfer-Korting, M

    2010-01-01

    In recent years many efforts have been made to replace dermal toxicity testing of chemicals in the animal by in vitro assays. As a member of a German research consortium, we have previously contributed to the validation of an in vitro test protocol for percutaneous absorption studies on the basis of reconstructed human epidermis and both human and pig skin ex vivo. Aiming to assess the barrier properties of a newly developed reconstructed skin model, this protocol has now been transferred to the Phenion Full-Thickness Skin Model (FT model). The permeation of testosterone and caffeine was quantified in parallel to that of pig skin using Franz-type diffusion cells. In addition, the permeation of benzoic acid and nicotine was studied. As expected, the FT model is more permeable than pig skin, yet its barrier properties are well in accordance with those of reconstructed human epidermis when compared to previous data. In fact, the FT model most efficiently retards testosterone as the compound of highest lipophilicity, which can be explained by an additional uptake by a reservoir formed by the dermis equivalent. Thus, the structure closely parallels human skin. In consequence, the Phenion FT model appears to be suitable for percutaneous absorption studies in hazard analysis and should be subjected to a catch-up validation study.

  18. A computer program based on parallel line assay for analysis of skin tests.

    PubMed

    Martín, S; Cuesta, P; Rico, P; Cortés, C

    1997-01-01

    A computer program for the analysis of differences or changes in skin sensitivity has been developed. It is based on parallel line assay, and its main features are its ability to conduct a validation process which ensures that the data from skin tests conform to the conditions imposed by the analysis which is carried out (regression, parallelism, etc.), the estimation of the difference or change in skin sensitivity, and the determination of the 95% and 99% confidence intervals of this estimation. This program is capable of managing data from independent groups, as well as paired data, and it may be applied to the comparison of allergen extracts, with the aim of determining their biologic activity, as well as to the analysis of changes in skin sensitivity appearing as a consequence of treatment such as immunotherapy.

  19. Penicillin hypersensitivity: value of clinical history and skin testing in daily practice.

    PubMed

    Kalogeromitros, Dimitrios; Rigopoulos, Dimitrios; Gregoriou, Stamatios; Papaioannou, Dimitrios; Mousatou, Vassiliki; Katsarou-Katsari, Alexandra

    2004-01-01

    Penicillin often is excluded as a treatment option based on patients' self-reported history of an adverse reaction to penicillin. The objective of this prospective study was to determine the likelihood of true penicillin allergy in patients with vague and convincing histories of penicillin allergy and to evaluate the diagnostic value added by appropriate skin testing. Six hundred thirty-eight patients with prior beta-lactam intake had a current indication for penicillin therapy and were referred for testing with the major (benzylpenicilloyl polylysine) and minor (minor determinant mixture) penicillin determinants from the inpatient and outpatient service of Athens University Dermatological hospital from January 2000 to December 2002. The prevalence of positive skin tests in the total group and in those patients with vague and convincing histories of penicillin allergy was determined. Positive skin tests were observed in 19/638 (3%) of the total group, 5 out of 542 (0.9%) patients without any history of penicillin allergy, 14 out of 96 (14.6%) patients with vague history (confidence interval [CI] 95% = 5.95-59.92), and 13 out of 18 (72.2%) patients with a convincing history of type I hypersensitivity reaction (chi2 = 286.3: odds ratio = 281.3: CI 95% = 62.19-1440.8). Patients with a vague history of penicillin allergy are 18 times more likely to have a positive penicillin skin test, and a convincing reaction history increases the likelihood by 281-fold compared with patients without a history of penicillin allergy. However, the fact that 5 of 18 (27.8%) patients with a convincing history were negative when skin tested points out that skin testing is helpful if the need for penicillin administration is compelling.

  20. 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.

  1. Interaction of O and OH radicals with a simple model system for lipids in the skin barrier: a reactive molecular dynamics investigation for plasma medicine

    NASA Astrophysics Data System (ADS)

    Van der Paal, Jonas; Aernouts, Stefaan; van Duin, Adri C. T.; Neyts, Erik C.; Bogaerts, Annemie

    2013-10-01

    Plasma medicine has been claimed to provide a novel route to heal wounds and regenerate skin, although very little is currently known about the elementary processes taking place. We carried out a series of ReaxFF-based reactive molecular dynamics simulations to investigate the interaction of O and OH radicals with lipids, more specifically with α-linolenic acid as a model for the free fatty acids present in the upper skin layer. Our calculations predict that the O and OH radicals most typically abstract a H atom from the fatty acids, which can lead to the formation of a conjugated double bond, but also to the incorporation of alcohol or aldehyde groups, thereby increasing the hydrophilic character of the fatty acids and changing the general lipid composition of the skin. Within the limitations of the investigated model, no formation of possibly toxic products was observed.

  2. Travel-associated skin disease.

    PubMed

    Morris-Jones, Rachael; Morris-Jones, Stephen

    2012-09-01

    Travel associated skin disease is extremely common and a frequent cause of the returning traveller seeking medical attention. Widespread cutaneous eruptions usually represent reactive rashes, indicating an underlying systemic infection or allergic reaction. Patients with disseminated or spreading rashes following travel often present with fever and malaise. In contrast, those presenting with localised skin disease such as a blister, nodule, plaque, ulcer etc are usually well in themselves but have sustained a bite/sting/penetrating injury or introduction of infection directly into the skin at the affected site. As a general rule widespread rashes are investigated with blood tests/serology and localised lesions with a skin biopsy for culture and histology.

  3. A tiered approach to the use of alternatives to animal testing for the safety assessment of cosmetics: skin irritation.

    PubMed

    Macfarlane, Martin; Jones, Penny; Goebel, Carsten; Dufour, Eric; Rowland, Joanna; Araki, Daisuke; Costabel-Farkas, Margit; Hewitt, Nicola J; Hibatallah, Jalila; Kirst, Annette; McNamee, Pauline; Schellauf, Florian; Scheel, Julia

    2009-07-01

    Evaluation of the skin irritancy and corrosivity potential of an ingredient is a necessity in the safety assessment of cosmetic ingredients. To date, there are two formally validated alternatives to the rabbit Draize test for skin corrosivity in place, namely the rat skin transcutaneous electrical resistance (TER) assay and the Human Skin Model Test using EpiSkin, EpiDerm and SkinEthic reconstructed human epidermal equivalents. For skin irritation, EpiSkin, EpiDerm and SkinEthic are validated as stand-alone test replacements for the rabbit Draize test. Data from these tests are rarely considered in isolation and are evaluated in combination with other factors to establish the overall irritating or corrosive potential of an ingredient. In light of the deadlines established in the Cosmetics Directive for cessation of animal testing for cosmetic ingredients, a COLIPA scientific meeting was held in Brussels on 30th January, 2008 to review the use of alternative approaches and to set up a decision tree approach for their integration into tiered testing strategies for hazard and safety assessment of cosmetic ingredients and their use in products. In conclusion, the safety assessments for skin irritation/corrosion of new chemicals for use in cosmetics can be confidently accomplished using exclusively alternative methods.

  4. Correlation of quantitative tests of nerve and target organ dysfunction with skin immunohistology in leprosy.

    PubMed

    Facer, P; Mathur, R; Pandya, S S; Ladiwala, U; Singhal, B S; Anand, P

    1998-12-01

    Loss of nociception and hypohidrosis in skin are hallmarks of leprosy, attributed to early invasion by Mycobacterium leprae of Schwann cells related to unmyelinated nerve fibres. We have studied skin lesions and contralateral clinically unaffected skin in 28 patients across the leprosy spectrum with a range of selective quantitative sensory and autonomic tests, prior to biopsy of both sites. Unaffected sites showed normal skin innervation, when antibodies to the pan-neuronal marker PGP (protein gene product) 9.5 were used, with the exception of intraepidermal fibres which were not detected in the majority of cases. Elevation of thermal thresholds and reduced sensory axon-reflex flare responses in affected skin correlated with decreased nerve fibres in the subepidermis, e.g. axon-reflex flux units (means+/-SEM) for no detectable innervation; decreased innervation; and clinically unaffected skin, were 23+/-3.1; 41.2+/-7.3; and 84.5+/-4.0, respectively. Reduced nicotine-induced axon-reflex sweating was correlated with decreased innervation of sweat glands. Where methacholine-induced direct activation of sweat glands was affected, there was inflammatory infiltrate and loss of sweat gland structure. This study demonstrates a correlation between selective nerve dysfunction on clinical tests and morphological changes in skin, irrespective of the type of leprosy, and is the first to show that loss of sweating in leprosy may result either from decreased innervation and/or involvement of the sweat glands. The findings have implications for the selection and monitoring of patients with leprosy in clinical trials which aim to restore cutaneous function.

  5. 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 Section 866.5270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems §...

  6. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false C-reactive protein immuno-logical test system. 866.5270 Section 866.5270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems §...

  7. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false C-reactive protein immuno-logical test system. 866.5270 Section 866.5270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems §...

  8. 21 CFR 866.5270 - C-reactive protein immuno-logical test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false C-reactive protein immuno-logical test system. 866.5270 Section 866.5270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems §...

  9. Outpatient penicillin use after negative skin testing and drug challenge in a pediatric population.

    PubMed

    Picard, Matthieu; Paradis, Louis; Nguyen, Mélanie; Bégin, Philippe; Paradis, Jean; Des Roches, Anne

    2012-01-01

    The practice of elective penicillin skin testing could be compromised by the fact that patients, their parents, or their physicians remain reluctant to reuse penicillin-class antibiotics (PCAs) despite a negative evaluation by an allergist. This study addresses reuse of PCAs in a pediatric population after negative penicillin skin testing and drug challenge and factors associated with its reluctance. All children evaluated for a history of penicillin allergy at the CHU Sainte-Justine Allergy Clinic between January 1998 and June 2000 with negative skin testing and drug challenge were included in the study. A telephone survey was conducted between May and October 2002 to assess the perception of the initial reaction by the parents, subsequent use of antibiotics, and antibiotic-related adverse reactions. Among the 200 children selected, parents of 170 (85%) children completed the survey. Since the allergist evaluation, 130 (76%) children had received antibiotics. PCA was used in 59 (45%) children. Parents of 24 (18%) children refused PCAs because they still feared an adverse reaction. They were more likely to have been very frightened by their child's allergic reaction than other parents whose children had used PCAs (p = 0.008). Although elective penicillin skin testing is useful and safe in the pediatric population, a significant proportion of parents still refuse PCAs even though they are needed. Identification of parents that were very frightened by their children's allergic reactions and additional reassurance could improve this situation.

  10. 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.

  11. 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

  12. Antibiotic allergies in children and adults: from clinical symptoms to skin testing diagnosis.

    PubMed

    Romano, Antonino; Caubet, Jean-Christoph

    2014-01-01

    Hypersensitivity reactions to β-lactam and non-β-lactam antibiotics are commonly reported. They can be classified as immediate or nonimmediate according to the time interval between the last drug administration and their onset. Immediate reactions occur within 1 hour after the last drug administration and are manifested clinically by urticaria and/or angioedema, rhinitis, bronchospasm, and anaphylactic shock; they may be mediated by specific IgE-antibodies. Nonimmediate reactions occur more than 1 hour after the last drug administration. The most common manifestations are maculopapular exanthems; specific T lymphocytes may be involved in this type of manifestation. The diagnostic evaluation of hypersensitivity reactions to antibiotics is usually complex. The patient's history is fundamental; the allergic examination is based mainly on in vivo tests selected on the basis of the clinical features and the type of reaction, immediate or nonimmediate. Immediate reactions can be assessed by immediate-reading skin tests and, in selected cases, drug provocation tests. Nonimmediate reactions can be assessed by delayed-reading skin tests, patch tests, and drug provocation tests. However, skin tests have been well validated mainly for β-lactams but less for other classes of antibiotics.

  13. Increased detection of latent tuberculosis by tuberculin skin test and booster phenomenon in early rheumatoid arthritis patients.

    PubMed

    Pérez-Barbosa, L; Esquivel-Valerio, J A; Arana-Guajardo, A C; Vega-Morales, D; Riega-Torres, J; Garza-Elizondo, M A

    2015-09-01

    The incidence of tuberculosis (TB) in rheumatoid arthritis (RA) patients is up to four times higher when compared to the general population, but their risk increases with the use of TNF-a drugs. Appropriate screening of latent tuberculosis infection (LTBI) and proper management of such cases substantially reduce the incidence of active TB. Tuberculin skin test (TST) is a widely used method for the detection of LTBI. The time of diagnosis of RA as well as the age of the patient might modify the TST performance. We did an observational, comparative study of RA patients with early and established disease, with the objective to know the prevalence of LTBI using the TST and booster test; an induration ≥5 mm was considered reactive. We evaluated 143 patients (83 [58 %] early RA patients). We found 31.3 and 21.7 % TST positivity in early and established RA patients, respectively. With the use of booster test, the positivity increased to 46.5 and 28.8 %, respectively (p = 0.048, OR 1.33, 95 % CI 1.01-1.75). In conclusion, we found that TST and booster test increased LTBI detection in early RA patients, which may suggest that time of RA diagnosis might affect cellular immunity and therefore the TST response.

  14. The adverse outcome pathway for skin sensitisation: Moving closer to replacing animal testing.

    PubMed

    Schultz, Terry W; Dimitrova, Gergana; Dimitrov, Sabcho; Mekenyan, Ovanes G

    2016-10-01

    This article outlines the work of the Organisation for Economic Co-operation and Development (OECD) that led to being jointly awarded the 2015 Lush Black Box Prize. The award-winning work centred on the development of 'The Adverse Outcome Pathway for Skin Sensitisation Initiated by Covalent Binding to Proteins'. This Adverse Outcome Pathway (AOP) has provided the mechanistic basis for the integration of skin sensitisation-related information. Recent developments in integrated approaches to testing and assessment, based on the AOP, are summarised. The impact of the AOP on regulatory policy and on the Three Rs are discussed. An overview of the next generation of the skin sensitisation AOP module in the OECD QSAR Toolbox, based on more-recent work at the Laboratory of Mathematical Chemistry, is also presented.

  15. Permeability test for transdermal and local therapeutic patches using Skin PAMPA method.

    PubMed

    Vizserálek, Gábor; Berkó, Szilvia; Tóth, Gergő; Balogh, Réka; Budai-Szűcs, Mária; Csányi, Erzsébet; Sinkó, Bálint; Takács-Novák, Krisztina

    2015-08-30

    Using the skin as absorption site presents unique advantages that have facilitated the progression of transdermal drug delivery in the past decades. Efforts in drug research have been devoted to find a quick and reproducible model for predicting the skin permeation of molecules. The Parallel Artificial Membrane Permeability Assay (PAMPA) has been extended for prediction of transdermal permeation by developing a model with completely artificial membrane, which can mimic the permeation through the stratum corneum. The present study aims to extend the Skin PAMPA method for testing transdermal and local therapeutic patches. The original method was modified and seven commercially available transdermal and local therapeutic patches with four different active pharmaceutical ingredients (nicotine, fentanyl, rivastigmine and ketoprofen) were studied. Data were compared to the declared delivery rates that are indicated by the manufacturers. Ex vivo permeation study was also performed in order to compare the permeated amount of the released drugs obtained by the two methods. The flux across the artificial membrane as well as the human skin (ex vivo) has been calculated and compared to the in vivo flux deduced from the labelled delivery rate and the active area of the patches. The results suggest that Skin PAMPA system can serve as a useful tool for evaluation and classification of the transdermal patches.

  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. 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

  18. Filling the concept with data: integrating data from different in vitro and in silico assays on skin sensitizers to explore the battery approach for animal-free skin sensitization testing.

    PubMed

    Natsch, Andreas; Emter, Roger; Ellis, Graham

    2009-01-01

    Tests for skin sensitization are required prior to the market launch of new cosmetic ingredients. Significant efforts are made to replace the current animal tests. It is widely recognized that this cannot be accomplished with a single in vitro test, but that rather the integration of results from different in vitro and in silico assays will be needed for the prediction of the skin sensitization potential of chemicals. This has been proposed as a theoretical scheme so far, but no attempts have been made to use experimental data to prove the validity of this concept. Here we thus try for the first time to fill this widely cited concept with data. To this aim, we integrate and report both novel and literature data on 116 chemicals of known skin sensitization potential on the following parameters: (1) peptide reactivity as a surrogate for protein binding, (2) induction of antioxidant/electrophile responsive element dependent luciferase activity as a cell-based assay; (3) Tissue Metabolism Simulator skin sensitization model in silico prediction; and (4) calculated octanol-water partition coefficient. The results of the in vitro assays were scaled into five classes from 0 to 4 to give an in vitro score and compared to the local lymph node assay (LLNA) data, which were also scaled from 0 to 4 (nonsensitizer/weak/moderate/strong/extreme). Different ways of evaluating these data have been assessed to rate the hazard of chemicals (Cooper statistics) and to also scale their potency. With the optimized model an overall accuracy for predicting sensitizers of 87.9% was obtained. There is a linear correlation between the LLNA score and the in vitro score. However, the correlation needs further improvement as there is still a relatively high variation in the in vitro score between chemicals belonging to the same sensitization potency class.

  19. 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

  20. 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

  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. 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.

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

    SciTech Connect

    Johnson, Raymond H.; Morrison, Stan; Morris, Sarah; Tigar, Aaron; Dam, William; Dayvault, Jalena

    2016-04-26

    Motivation for Study: Natural flushing of contaminants at various U.S. Department of Energy Office of Legacy Management sites is not proceeding as quickly as predicted (plume persistence) Objectives: Help determine natural flushing rates using column tests. Use 1D reactive transport modeling to better understand the major processes that are creating plume persistence Approach: Core samples from under a former mill tailings area Tailings have been removed. Column leaching using lab-prepared water similar to nearby Gunnison River water. 1D reactive transport modeling to evaluate processes

  4. Active tuberculosis among Iraqi schoolchildren with positive skin tests and their household contacts.

    PubMed

    Al Kubaisy, W; Al Dulayme, A; Hashim, D S

    2003-07-01

    In a prospective cohort study in Iraq, schoolchildren with a positive tuberculin skin test during the nationwide survey in 2000 were followed up in 2002 to determine prevalence of latent tuberculosis (TB) infection and risk factors among household contacts. Of 205 children, 191 remained skin-test positive in 2002. Based on X-ray and clinical examination, 9 children (4.4%) were active TB cases. Among 834 household contacts, there were 144 new TB cases, giving a cumulative incidence of 17.3%. Risk factors for TB among household contacts were: age > or = 15 years; technical/professional job; smoking; low body mass index; diabetes mellitus; steroid therapy; and closeness of contact with the index cases. Based on past history of TB in index children and their contacts, 77.2% of new TB cases were attributable to household contacts.

  5. Skin Test for Paragonimiasis among Schoolchildren and Villagers in Namback District, Luangprabang Province, Lao PDR

    PubMed Central

    Song, Hyun-Ouk; Rim, Han-Jong; Youthanavanh, Vonghachack; Daluny, Bouakhasith; Sengdara, Vongsouvan; Virasack, Banouvong; Bounlay, Phommasak

    2008-01-01

    As a part of a broader effort to determine the status of Paragonimus species infection in Lao PDR, an epidemiological survey was conducted on villagers and schoolchildren in Namback District between 2003 and 2005. Among 308 villagers and 633 primary and secondary schoolchildren, 156 villagers and 92 children evidenced a positive reaction on a Paragonimus skin test. Only 4 schoolchildren out of 128 skin test-positive cases had Paragonimus sp. eggs in their sputum, all of which was collected on 1 day. Several types of crabs, which were identified as the second intermediate host of the Paragonimus species, were collected from markets and streams in a paragonimiasis endemic area for the inspection of metacercariae. Among the examined crabs, only "rock crabs" (Indochinamon ou) harbored Paragonimus sp. metacercariae, and it is speculated that the life cycle of Paragonimus sp. was maintained via rock crabs in Namback District, Lao PDR. PMID:18830059

  6. 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

  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.

  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. 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.

  10. 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.

  11. 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.

  12. Reactivating the extracellular matrix synthesis of sulfated glycosaminoglycans and proteoglycans to improve the human skin aspect and its mechanical properties

    PubMed Central

    Chajra, Hanane; Auriol, Daniel; Joly, Francine; Pagnon, Aurélie; Rodrigues, Magda; Allart, Sophie; Redziniak, Gérard; Lefevre, Fabrice

    2016-01-01

    Background The aim of this study was to demonstrate that a defined cosmetic composition is able to induce an increase in the production of sulfated glycosaminoglycans (sGAGs) and/or proteoglycans and finally to demonstrate that the composition, through its combined action of enzyme production and synthesis of macromolecules, modulates organization and skin surface aspect with a benefit in antiaging applications. Materials and methods Gene expression was studied by quantitative reverse transcription polymerase chain reaction using normal human dermal fibroblasts isolated from a 45-year-old donor skin dermis. De novo synthesis of sGAGs and proteoglycans was determined using Blyscan™ assay and/or immunohistochemical techniques. These studies were performed on normal human dermal fibroblasts (41- and 62-year-old donors) and on human skin explants. Dermis organization was studied either ex vivo on skin explants using bi-photon microscopy and transmission electron microscopy or directly in vivo on human volunteers by ultrasound technique. Skin surface modification was investigated in vivo using silicone replicas coupled with macrophotography, and the mechanical properties of the skin were studied using Cutometer. Results It was first shown that mRNA expression of several genes involved in the synthesis pathway of sGAG was stimulated. An increase in the de novo synthesis of sGAGs was shown at the cellular level despite the age of cells, and this phenomenon was clearly related to the previously observed stimulation of mRNA expression of genes. An increase in the expression of the corresponding core protein of decorin, perlecan, and versican and a stimulation of their respective sGAGs, such as chondroitin sulfate and heparan sulfate, were found on skin explants. The biosynthesis of macromolecules seems to be correlated at the microscopic level to a better organization and quality of the dermis, with collagen fibrils having homogenous diameters. The dermis seems to be

  13. Herbal preparation extract for skin after radiotherapy treatment. Part One--Preclinical tests.

    PubMed

    Skalska-Kamińska, Agnieszka; Woźniak, Anna; Paduch, Roman; Kocjan, Ryszard; Rejdak, Robert

    2014-01-01

    Naran R is a herbal composition made of Plantago lanceolate folium, Malvae arboreae flos, Calendulae flos, Chamomillae inflorescentia, Lamii albi flos to prepare compresses or to wash skin with inflammations. The extract of this preparation is mixed to be applied as an ointment on patients' skin after radiotherapy. Experiments performed in vitro are part of pre-clinical tests with Naran R ointment. This study examined the impact of the plant composition for ethanol-water extract on human skin fibroblasts (HSF) culture. Samples of extract, prepared from patented amounts of herbs, were in the range of 25-225 μg/mL. Six methods were applied: standard spectrophotometric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, neutral red (NR) uptake assay, DPPH free radical scavenging test, labeling of cytoskeleton F-actin, staining of argyrophilic nucleolar organizer regions (AgNORs) and trypan blue coloration. The extract concentration 75 μg/mL was established as safe for application on human skin. In labeling of F-actin with rhodamine-phalloidin dye at this concentration the cytoskeleton was stable. The extract did not influence the membrane stability and had positive influence on the proliferation activity. It was confirmed in AgNOR test during incubation with extract, which led to formation of larger amount of smaller nucleolins. In DPPH scavenging activity test, the extract revealed over 8% higher free-radical scavenging activity in comparison to control. After trypan blue staining, the extract in concentration 125 μg/mL significantly lowered the cell viability. When the cytotoxic and anti-proliferative activity of the extracts were analyzed, MTT and Neutral Red (NR) methods were used. The cells' viability was maintained on a constant level (80-110%) after 24, 48 and 72 h of incubation. During all time of NR test (72 h) and even when 225 μg/mL of extract was applied, the viability of cells was in range 80-110% of control. Positive influence

  14. 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.

  15. Determination of wavelength-specific UV protection factors of sunscreens in intact skin by EPR measurement of UV-induced reactive melanin radical.

    PubMed

    Lund, Leslie; Ley, Ronald D; Felton, Linda A; Timmins, Graham S

    2007-01-01

    There remains an unmet need for skin tissue-based assays for the measurement of the UVA protection and efficacy of sunscreens. Here we describe development of a novel electron paramagnetic resonance assay that uses the photogeneration of reactive melanin radical as a measure of UV light penetration to melanocytes in situ in skin. We have used areas of focal melanocytic hyperplasia in the skin of Monodelphis domestica to model the human nevus. We show that we are able to use this assay to determine the monochromatic protection factors (mPF) of research and commercial sunscreens at specific narrow wavebands of UVB, UVA and blue visible light. Both commercial sunscreens, a sun protection factor (SPF) 4 and an SPF 30 product, had mPFs in the UVB range that correlated well with their claimed SPF. However, their mPF in the UVA ranges were only about one-third of claimed SPF. This technique can be used to design and assay sunscreens with optimally balanced UVA and UVB protection.

  16. Thermography for skin temperature evaluation during dynamic exercise: a case study on an incremental maximal test in elite male cyclists.

    PubMed

    Ludwig, Nicola; Trecroci, Athos; Gargano, Marco; Formenti, Damiano; Bosio, Andrea; Rampinini, Ermanno; Alberti, Giampietro

    2016-12-01

    The use of thermal imaging in monitoring the dynamic of skin temperature during prolonged physical exercise is central to assess athletes' ability to dissipate heat from the skin surface to the environment. In this study, seven elite cyclists completed an incremental maximal cycling test to evaluate their skin temperature response under controlled-environment conditions. Thermal images have been analyzed using a method based on maxima detection (Tmax). Data confirmed a reduction in skin temperature due to vasoconstriction during the exercise, followed by a temperature increment after exhaustion. A characteristic hot-spotted thermal pattern was found over the skin surface in all subjects. This research confirmed also the notable ability by highly trained cyclists to modify skin temperature during an incremental muscular effort. This study gives additional contributions for understanding the capability of the Tmax method applied to the thermoregulatory physiological processes.

  17. New skin test for detection of bovine tuberculosis on the basis of antigen-displaying polyester inclusions produced by recombinant Escherichia coli.

    PubMed

    Chen, Shuxiong; Parlane, Natalie A; Lee, Jason; Wedlock, D Neil; Buddle, Bryce M; Rehm, Bernd H A

    2014-04-01

    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.

  18. In vitro human skin irritation test for evaluation of medical device extracts.

    PubMed

    Casas, J W; Lewerenz, G M; Rankin, E A; Willoughby, J A; Blakeman, L C; McKim, J M; Coleman, K P

    2013-12-01

    The aim of this study was to determine if the EpiDerm™ reconstructed human skin model (MatTek Corp.) could be an acceptable alternative to the ISO 10993-required rabbit skin irritation test for assessing medical device biocompatibility. Eleven medical device polymers were tested. Four extracts were prepared per polymer, two each with saline and sesame oil; half were spiked with two R-38 irritants, lactic acid for saline extracts and heptanoic acid for the sesame oil extracts. Tissue viability was assessed by MTT reduction and the proinflammatory response was assessed by IL-1α release. LOAELs of 2% for lactic acid in saline and 0.7% for heptanoic acid in sesame oil were determined. A cell viability reduction of >50% was indicative of skin irritation. Cells exposed to saline extracts spiked with 3.25% lactic acid had significantly reduced mean cell viabilities (12.6-17.2%). Cells exposed to sesame oil extracts spiked with 1.25% heptanoic acid also exhibited reduced mean cell viabilities (25.5%-41.7%). All spiked cells released substantial amounts of IL-1α (253.5-387.4pg/ml) signifying a proinflammatory response. These results indicate that the EpiDerm™ model may be a suitable in vitro replacement for the assessment of the irritation potential of medical device extracts.

  19. 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.

  20. Wearing test with 2 different types of latex gloves with and without the use of a skin protection cream.

    PubMed

    Allmers, H

    2001-01-01

    72 subjects reporting symptoms indicating Type I hypersensitivity reactions to natural rubber latex (NRL) gloves were included in this study. 44 of them had a positive prick test to NRL. They underwent wearing tests using 2 types of NRL gloves with high (n=63) and low (n=70) allergen contents. Unigloves Malaysia with a high allergen content caused positive skin reactions in 47% of SPT-positive and no IgE-negative subjects. After application of Hand Sense skin protection cream, the frequency of positive skin responses in wearing tests decreased to 30% in prick-test-positive subjects. The Biogel Diagnostic gloves with low allergen caused hypersensitivity with and without Hand Sense in 2 cases (5%) of the prick-test-positive. 60% of all test participants had a positive prick test to NRL. No prick-test-negative subjects showed any urticaria during the glove-wearing test. Our study demonstrates that high allergen contents in latex gloves frequently elicit skin responses in NRL-sensitized subjects. Since other skin protection creams have shown to increase allergic symptoms, it is encouraging to report that Hand Sense skin cream may hamper the uptake of allergens from gloves, thus decreasing allergic reactions.

  1. 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.

  2. [Thermal test of reactive hyperemia: a propos of an objective study of pyridinol carbamate].

    PubMed

    Lauliac, M

    1978-01-01

    The thermal test of reactive hyperhemia (TTHR) gives a global and reliable appreciation of the cutaneous microcirculation, the importance of which is well known. In this study, sixty-one subjects were treated for from one month to one year with pyridinol-carbamate. The TTHR was modified in seventy-nine per cent of the cases, showing a considerable and lasting improvement. The clinical symptoms followed a comparable evolution.

  3. Patch-testing with serial dilutions of tixocortol pivalate and potential cross-reactive substances.

    PubMed

    Isaksson, M; Bruze, M; Goossens, A; Lepoittevin, J P

    2000-01-01

    Of patch-tested patients with dermatitis, 4-5% are allergic to corticosteroids. Four groups of corticosteroids are recognized (A-D), where substances from the same group may cross-react. We investigated the potential cross-reactivity pattern and dose-response relationship for several corticosteroids from group A. We also included the corresponding aldehyde to hydrocortisone, as this degradation product has been proposed to be immunogenic. Eleven patients shown to be allergic to tixocortol pivalate were patch-tested with several corticosteroids from group A, as well as with the aldehyde, all in serial dilutions. All 11 reacted to both tixocortol pivalate and hydrocortisone. The dose-response relationship for the corticosteroids tended to be similar to sensitizers lacking anti-inflammatory potential. Patients with simultaneous reactions to many substances had high patch-test reactivity to tixocortol pivalate and hydrocortisone, while patients with few such reactions showed low reactivity (p=0.001 and 0.003, respectively). Several patients reacted to the aldehyde, supporting the theory that it is an intermediate in sensitization.

  4. Does effect of BCG vaccine decrease with time since vaccination and increase tuberculin skin test reaction?

    PubMed

    Subramani, R; Datta, Manjula; Swaminathan, S

    2015-10-01

    The protective efficacy of BCG was studied for over 15 years, from 1968, in South India. A secondary analysis of data was performed to investigate the relationship between Bacille Calmette-Guérin (BCG) and tuberculosis (TB) disease and between BCG and positive tuberculin skin test for different time periods among children aged less than 10 years. A randomized controlled trial was conducted, where 281,161 persons were allocated to receive BCG 0.1mg, BCG 0.01mg or placebo. Tuberculin skin test was performed at baseline and at 4 years after BCG vaccination. Surveys were conducted every 2.5 years to detect all new cases of culture-positive/smear-positive TB occurring in the community over a 15-year period. Relative risk (RR) was obtained from the ratio of incidence among the vaccinated and the placebo groups. Among those children vaccinated with 0.1mg of BCG, the RR for TB was 0.56 (95% CI: 0.32-0.87, P=0.01) at 12.5 years but increased to 0.73 later. Similar pattern was seen with 0.01mg. The increase in the number of skin test positives with 0.1mg of BCG was 57.8%, 49.4% and 34% for cut-off points at ≥10mm, ≥12mm and ≥15mm, respectively. The study suggests that the effect of BCG may decrease since vaccination and the tuberculin positive was higher at post-vaccination test period due to BCG.

  5. Autologous Serum and Plasma Skin Tests in Chronic Spontaneous Urticaria: A Reappraisal

    PubMed Central

    Kumaran, Muthu Sendhil; Mangal, Sonia; Narang, Tarun; Parsad, Davinder

    2017-01-01

    Aim: The objective of this study was to assess autologous serum skin test (ASST) vs autologous plasma skin test (APST) response in chronic spontaneous urticaria (CSU) patients and study the significance of intensity of positive responses in relation to clinicoepidemiological parameters. Materials and Methods: One hundred CSU patients and 100 age and sex-matched controls were recruited. The demographic and clinical features were recorded in all patients and routine investigations were performed. ASST and APST tests were performed as per the standard guidelines. Results: The mean duration of illness was 4.85 ± 5.07 years, 90% patients were APST (+), 68% ASST (+), and 22 patients were only APST (+). Positive predictive value (PPV) of ASST and APST was 90.7% and 95.7%, respectively. A significant inverse association was seen between thyroid status and serum IgE levels with APST and ASST positivity. Conclusion: APST appears to have better PPV and high intensity of positive response on autologous tests, and correlates with ANA positivity and angioedema.

  6. Assessment of skin test with varicella-zoster virus antigen for predicting the risk of herpes zoster.

    PubMed

    Okuno, Y; Takao, Y; Miyazaki, Y; Ohnishi, F; Okeda, M; Yano, S; Kumihashi, H; Gomi, Y; Maeda, K; Ishikawa, T; Mori, Y; Asada, H; Iso, H; Yamanishi, K

    2013-04-01

    The Shozu Herpes Zoster (SHEZ) Study was designed to clarify the incidence of and predictive and immunological factors for herpes zoster in a defined community-based Japanese population. As part of this series, a total of 5683 residents aged ≥50 years received a varicella-zoster virus (VZV) skin test with VZV antigen, and 48 h later, the erythema and oedema were assessed by measuring the longest diameter. The diameters of both the erythema and oedema decreased with the increasing age of the subject. Sixty-three subjects contracted herpes zoster within a year after receiving the VZV skin test. Analysis of the herpes zoster incidence rate vs. the skin test reaction revealed that the shorter the diameter of erythema or oedema, the greater the likelihood of herpes zoster. These results demonstrated that the VZV skin test is an excellent surrogate marker for predicting the risk of herpes zoster.

  7. Adaptation of the KeratinoSens™ skin sensitisation test to animal-product-free cell culture.

    PubMed

    Belot, Nathalie; Sim, Bushra; Longmore, Christopher Longmore; Roscoe, Lottie; Treasure, Carol

    2017-03-16

    Skin sensitisation is the process by which a substance leads to an allergic reaction following skin contact. The process has been described as an adverse outcome pathway (AOP), including several key events, from skin penetration and covalent protein binding, to keratinocyte activation, dendritic cell activation and T-lymphocyte proliferation. The in vitro assay KeratinoSens™ measures the activation of keratinocytes. It is fully accepted at a regulatory level (OECD TG 442d) and appropriate for compliance with a range of legislation including the EU Cosmetics Regulation, REACH, and the CLP Regulation. Currently, many in vitro methods use animal-derived components in the cell culture systems. Many stakeholders in the cosmetics industry have both scientific and ethical concerns relating to this issue and have stated a strong preference for fully human in vitro test systems. We have adapted the KeratinoSensTM method to animal product-free conditions, and carried out an in-house validation with 21 reference substances, including those listed in the Performance Standards associated with OECD TG442d. The modified method was shown to be totally equivalent to the Validated Reference Method (VRM), with comparable values for accuracy (85.7%), sensitivity (84.6%) and specificity (87.5%), and all acceptance criteria being met. In Europe, data generated by the adapted method may be used in REACH submissions, and we are now seeking approval to list the adaptation in OECD TG 442d, enabling formal compliance with a range of global regulations.

  8. Immediate hypersensitivity to penicillins with negative skin tests--the value of specific IgE.

    PubMed

    Silva, R; Cruz, L; Botelho, C; Castro, E; Cadinha, S; Castel-Branco, M G; Rodrigues, J

    2009-08-01

    The determination of specific IgE in patients with history of penicillins hypersensitivity is simple, safe and widely available. The positive and negative predictive values of this determination, however, are not yet established. In order to evaluate them, we performed specific IgE determination and diagnostic drug challenges in a group of 22 patients with a clear history of immediate penicillins hypersensitivity but negative skin tests. In this sample, the positive and negative predictive values were 29% and 87%, respectively. This seems to indicate that a positive specific IgE is not enough to confirm the diagnosis, and further study is necessary.

  9. Testing Human Skin and Respiratory Sensitizers—What Is Good Enough?

    PubMed Central

    Malmborg, Anki; Borrebaeck, Carl A. K.

    2017-01-01

    Alternative methods for accurate in vitro assessment of skin and respiratory sensitizers are urgently needed. Sensitization is a complex biological process that cannot be evaluated accurately using single events or biomarkers, since the information content is too restricted in these measurements. On the contrary, if the tremendous information content harbored in DNA/mRNA could be mined, most complex biological processes could be elucidated. Genomic technologies available today, including transcriptional profiling and next generation sequencing, have the power to decipher sensitization, when used in the right context. Thus, a genomic test platform has been developed, denoted the Genomic Allergen Rapid Detection (GARD) assay. Due to the high informational content of the GARD test, accurate predictions of both the skin and respiratory sensitizing capacity of chemicals, have been demonstrated. Based on a matured dendritic cell line, acting as a human-like reporter system, information about potency has also been acquired. Consequently, multiparametric diagnostic technologies are disruptive test principles that can change the way in which the next generation of alternative methods are designed. PMID:28125016

  10. 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.

  11. Cross-reactivity of stimulants found in sports drug testing by two fluorescence polarization immunoassays.

    PubMed

    de la Torre, R; Badia, R; Gonzàlez, G; García, M; Pretel, M J; Farré, M; Segura, J

    1996-01-01

    We investigated the usefulness of immunological methods for presumptive detection of stimulants found in sports drug testing. The ingestion of substances that show no cross-reactivity in tests commercially available for the detection of amphetamines can produce positive results in the urine. Human metabolism contributes to the positive results of some urine samples when the parent compound does not cross-react with the antibodies of the assay. Urine samples from healthy volunteers given stimulants were tested by chromatographic methods and by two different fluorescence polarization immunoassays (FPIA) from Abbott Laboratories for the analysis of amphetamines. According to the results obtained, we classified stimulants into four groups: detectable stimulants that gave rise to amphetamine by human metabolism (group 1); detectable ephedrines and related compounds, appearing in the urine either as parent compounds or originated by metabolism (group 2); detectable stimulants that displayed actual cross-reactivity with amphetamine tests (group 3); and stimulants not detected by FPIA (group 4). Most of the true doping cases due to the ingestion of stimulants may be detected by FPIA. The specificity of the results may be increased by combining immunological assays with different antibodies.

  12. 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.

  13. Bayesian integrated testing strategy to assess skin sensitization potency: from theory to practice.

    PubMed

    Jaworska, Joanna; Dancik, Yuri; Kern, Petra; Gerberick, Frank; Natsch, Andreas

    2013-11-01

    Frameworks to predict in vivo effects by integration of in vitro, in silico and in chemico information using mechanistic insight are needed to meet the challenges of 21(st) century toxicology. Expert-based approaches that qualitatively integrate multifaceted data are practiced under the term 'weight of evidence', whereas quantitative approaches remain rare. To address this gap we previously developed a methodology to design an Integrated Testing Strategy (ITS) in the form of a Bayesian Network (BN). This study follows up on our proof of concept work and presents an updated ITS to assess skin sensitization potency expressed as local lymph node assay (LLNA) potency classes. Modifications to the ITS structure were introduced to include better mechanistic information. The parameters of the updated ITS were calculated from an extended data set of 124 chemicals. A detailed validation analysis and a case study were carried out to demonstrate the utility of the ITS for practical application. The improved BN ITS predicted correctly 95% and 86% of chemicals in a test set (n = 21) for hazard and LLNA potency classes, respectively. The practical value of using the BN ITS is far more than a prediction framework when all data are available. The BN ITS can develop a hypothesis using subsets of data as small as one data point and can be queried on the value of adding additional tests before testing is commenced. The ITS represents key steps of the skin sensitization process and a mechanistically interpretable testing strategy can be developed. These features are illustrated in the manuscript via practical examples.

  14. 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

  15. A Tuberculin Skin Test Survey and the Annual Risk of Mycobacterium tuberculosis Infection in Gambian School Children

    PubMed Central

    Adetifa, Ifedayo M. O.; Muhammad, Abdul Khalie; Jeffries, David; Donkor, Simon; Borgdorff, Martien W.; Corrah, Tumani; D’Alessandro, Umberto

    2015-01-01

    Background A Tuberculin skin test (TST) survey was conducted to assess the prevalence of latent TB Infection (LTBI) and to estimate the annual risk of M. tuberculosis infection (ARTI) in Gambian school children. The results are expected to contribute to understanding of Tuberculosis epidemiology in The Gambia. Methods This was a nationwide, multi-cluster survey in children aged 6–11 years. Districts, 20 of 37, were selected by probability proportional to size and schools by simple random sampling. All TST were performed using the Mantoux method. Height and weight measurements were obtained for all participants. We calculated prevalence of LTBI using cut-off points of 10mm, the mirror and mixture modelling methods. Results TST readings were completed 13,386 children with median age of 9 years (interquartile range [IQR] 8–10 years). Mixture analysis yielded a cut-off point of 12 mm, and LTBI prevalence of 6.9% [95%CI 6.47–7.37] and the ARTI was 0.75% [95%CI 0.60–0.91]. LTBI was associated gender and urban residence (p <0.01). Nutritional status was not associated with non-reactive TST or sizes of TST indurations. ARTI did not differ significantly by age, gender, BCG vaccination or residence. Conclusions This estimates for LTBI prevalence and ARTI were low but this survey provides updated data. Malnutrition did not affect estimates of LTBI and ARTI. Given the low ARTI in this survey and the overlapping distribution of indurations with mixture modelling, further surveys may require complementary tests such as interferon gamma release assays or novel diagnostic tools. PMID:26465745

  16. Multiple Skin Colored Nodules on both Legs in Patient with Positive QuantiFERON®-TB Gold Test

    PubMed Central

    Choi, Mi Soo; Hong, Seung Phil; Park, Byung Cheol

    2017-01-01

    Nodular tuberculid (NT) was originally described by Jordaan et al. in 2000 in 4 patients from South Africa. It appeared as nodules on the legs; the pathologic changes were situated in the deep dermis and adjacent subcutaneous fat. A 34-year-old woman visited our hospital with subcutaneous skin-colored or slightly erythematous round to oval nodules. Skin biopsies revealed granulomatous inflammation at the dermo-subcutaneous junction with vasculitis. Chest X-ray, tuberculosus (TB)-polymerase chain reaction and TB culture of the skin specimen were normal. A QuantiFERON®-TB Gold test (QUIAGEN, Germany) was positive, which suggested a diagnosis of latent TB infection. The patient was treated with anti-TB medication and her condition has not recurred. Herein, we report a case of a patient with latent TB diagnosed by a positive QuantiFERON®-TB Gold test whose skin lesions had the clinical and histopathologic features of NT. PMID:28223755

  17. Beyond skin testing: state of the art and new horizons in food allergy diagnostic testing.

    PubMed

    Caubet, Jean-Christoph; Sampson, Hugh A

    2012-02-01

    Food allergy affects approximately 1% to 10.8% of the general population, and its prevalence seems to be increasing. An accurate diagnosis is particularly important because a misdiagnosis could lead to life-threatening reactions or to unnecessary restrictive diets. However, allergy tests currently used in clinical practice have limited accuracy, and an oral food challenge, considered as the gold standard, is often required to confirm or exclude a food allergy. This article reviews several promising novel approaches for the diagnosis of food allergy, such as new molecular diagnostic technologies and functional assays, along with their potential clinical applications.

  18. Skin biopsy and quantitative sensory testing do not predict response to lidocaine patch in painful neuropathies.

    PubMed

    Herrmann, David N; Pannoni, Valerie; Barbano, Richard L; Pennella-Vaughan, Janet; Dworkin, Robert H

    2006-01-01

    Predictors of response to neuropathic pain treatment in patients with painful distal sensory neuropathies are lacking. The 5% lidocaine patch is believed to exert its effects on neuropathic pain via a local stabilizing effect on cutaneous sensory afferents. As such, it provides a model to assess whether the status of epidermal innervation as determined by skin biopsy or quantitative sensory testing (QST) of small- and large-diameter sensory afferents might serve as predictors of response to topical, locally active treatment. In this study we assessed associations between epidermal nerve fiber (ENF) densities, sensory nerve conduction studies (NCS), QST, and response to a 5% lidocaine patch in patients with painful distal sensory neuropathies. We observed no association between distal leg epidermal and subepidermal innervation and response to the lidocaine patch. Several patients with complete loss of distal leg ENF showed a response to the lidocaine patch. Similarly we observed no consistent association between treatment response and QST for vibration, cooling, warm, heat-pain, and cold-pain thresholds, or distal sensory NCS. Thus, distal-leg skin biopsy, QST, and sensory NCS cannot be used to identify patients with painful polyneuropathy likely to respond to a lidocaine patch in clinical practice. Further studies are required to clarify precisely the mechanism and site of action of the lidocaine patch in patients with peripheral neuropathic pain.

  19. Frequency-selective quantification of skin perfusion behavior during allergic testing using photoplethysmography imaging

    NASA Astrophysics Data System (ADS)

    Blanik, Nikolai; Blazek, Claudia; Pereira, Carina; Blazek, Vladimir; Leonhardt, Steffen

    2014-03-01

    Diagnosis of allergic immediate-type reactions is dependent on the visual assessment of the attending physician. With our novel non-obtrusive, camera-based photoplethysmography imaging (PPGI) setup, perfusion in the allergic testing area can be quantified and results displayed with spatial resolution in functional mappings. Thereby, each PPGI camera pixel can be assumed to be a classical (skin-based) reflective mode PPG sensor. An algorithm for post-processing of collected PPGI video sequences was developed to transfer black-and-white PPGI images into virtual 3D perfusion maps. For the first time, frequency selected perfusion quantification was assessed. For the presented evaluation, PPGI data from our clinical study were used [1]. For this purpose, different concentrations of histamine dilutions were administered to 27 healthy volunteers. Our results show clear trends in an increase in heartbeat synchronous perfusion rhythms and, simultaneously, a decrease of lower frequency vasomotor rhythms in these areas. These results, published for the first time, allow new insight into the distribution of skin perfusion dynamics and demonstrate the intuitive clinical usability of the proposed system.

  20. Histamine 50-Skin-Prick Test: A Tool to Diagnose Histamine Intolerance

    PubMed Central

    Kofler, Lukas; Ulmer, Hanno; Kofler, Heinz

    2011-01-01

    Background. Histamine intolerance results from an imbalance between histamine intake and degradation. In healthy persons, dietary histamine can be sufficiently metabolized by amine oxidases, whereas persons with low amine oxidase activity are at risk of histamine toxicity. Diamine oxidase (DAO) is the key enzyme in degradation. Histamine elicits a wide range of effects. Histamine intolerance displays symptoms, such as rhinitis, headache, gastrointestinal symptoms, palpitations, urticaria and pruritus. Objective. Diagnosis of histamine intolerance until now is based on case history; neither a validated questionnaire nor a routine test is available. It was the aim of this trial to evaluate the usefullness of a prick-test for the diagnosis of histamine intolerance. Methods. Prick-testing with 1% histamine solution and wheal size-measurement to assess the relation between the wheal in prick-test, read after 20 to 50 minutes, as sign of slowed histamine degradation as well as history and symptoms of histamine intolerance. Results. Besides a pretest with 17 patients with HIT we investigated 156 persons (81 with HIT, 75 controls): 64 out of 81 with histamine intolerance(HIT), but only 14 out of 75 persons from the control-group presented with a histamine wheal ≥3 mm after 50 minutes (P < .0001). Conclusion and Clinical Relevance. Histamine-50 skin-prickt-test offers a simple tool with relevance. PMID:23724226

  1. Effects of different base agents on prediction of skin irritation by sodium lauryl sulfate using patch testing and repeated application test.

    PubMed

    Horita, Kotomi; Horita, Daisuke; Tomita, Hiroyuki; Yasoshima, Mitsue; Yagami, Akiko; Matsunaga, Kayoko

    2017-03-06

    Animal testing for cosmetics was banned in the European Union (EU) in 2013; therefore, human tests to predict and ensure skin safety such as the patch test or usage test are now in demand in Japan as well as in the EU. In order to investigate the effects of different bases on the findings of tests to predict skin irritation, we performed patch testing (PT) and the repeated application test (RAT) using sodium lauryl sulfate (SLS), a well-known irritant, dissolved in 6 different base agents to examine the effects of these bases on skin irritation by SLS. The bases for PT were distilled water, 50% ethanol, 100% ethanol, a gel containing 50% ethanol, white petrolatum, and hydrophilic cream. The concentrations of SLS were 0.2% and 0.5%. Twelve different base combinations were applied to the normal back skin of 19 individuals for 24h. RAT was performed with distilled water, 50% ethanol, 100% ethanol, a gel containing 50% ethanol, white petrolatum, and hydrophilic cream containing SLS at concentrations of 0.2%, 2%, and 5%, being applied to the arms of the same PT subjects. The test preparation of each base was applied at the same site, with 0.2% SLS being used in the first week, 2% SLS in the following week, and 5% SLS in the final week. The results of PT revealed that skin irritation scores varied when SLS at the same concentration was dissolved in a different base. The results of RAT showed that although skin irritation appeared with every base at a concentration of 5%, the positive rate was approximately the same. In conclusion, our results suggest that skin irritation elicited in PT depends on the base, while in RAT, it does not depend on the type of base employed.

  2. Involvement of cross-reactive carbohydrate determinants-specific IgE in pollen allergy testing

    PubMed Central

    Yoshitake, Hiroshi; Matsumoto, Yuma; Kawada, Michitsugu; Takato, Yoshiki; Shinagawa, Kiyomi; Sakurai, Hiroyuki; Saito, Koichiro

    2017-01-01

    Background Specific IgE antibodies against the low-molecular-weight carbohydrate antigen that does not bridge IgE molecules on mast cells are not associated with clinical symptoms. Cross reactivity can be determined in allergen-specific IgE detection assays when the carbohydrate structures between pollen allergens and plant derived food allergens are similar; in such cases, false positive results for grain or legume allergens can be reported for pollen allergic patients who are not sensitized to those allergens. This phenomenon arises owing to the presence of cross-reactive carbohydrate determinants (CCDs). Objective This study aimed to assess the impact of CCD interference on the results for pollen allergen-specific IgE antibodies in the general adult population and to perform CCD inhibition tests evaluating the involvement of CCD on samples positive to pollen allergens. Methods Serum samples from 322 subjects were tested for IgE antibodies to pollens and CCD. The research subjects were given questionnaires about pollen allergic symptoms to help assess the presence of allergies. Allergen IgE antibodies for Japanese cedar, Japanese cypress, orchard grass, ragweed, MUXF, bromelain, horseradish peroxidase (HRP), and ascorbate oxidase (ASOD) were analyzed. Results It was observed that among individuals who tested positive to any of the pollen allergens, the positive ratio of CCD-specific IgE antibody was the highest for HRP (13.5%–50.0%). The results from the inhibition tests revealed that CCD was marginally present. Although IgE antibodies for cedar pollen did not react with CCD, IgE antibodies for Japanese cypress, orchard grass, and ragweed might be detected by the presence of CCD. Conclusion The results of the inhibition tests revealed the obvious presence of CCD suggesting its involvement. Considering these findings, careful evaluation of patient IgE results should be performed for Japanese cypress, orchard grass, and ragweed. PMID:28154803

  3. 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.

  4. The Efficiacy of Sternocleidomastoid Muscle Flap on Frey's Syndrome via a Novel Test: Galvanic Skin Response.

    PubMed

    Demirci, Ugur; Basut, Oguz; Noyan, Behzat; Demir, Uygar Levent; Afsin Ozmen, O; Kasapoglu, Fikret; Hakan Coskun, H; Onart, Selcuk

    2014-01-01

    The aim of this study was to evaluate the effects of sternocleidomastoid (SCM) muscle flap on preventing Frey's syndrome by using, Galvanic skin responses (GSR). Fourty-three patients who underwent superficial parotidectomy were randomly divided into two groups and their GSR were recorded. SCM muscle flap was applied over the surgical area only in one group. Six months after the surgery, GSRs were remeasured. In addition, the patients completed a questionnaire regarding their complaints about clinical Frey's syndrome. Four patients had symptoms of clinical Frey's syndrome. Postoperative GSR measurements revealed no significant difference between two sides in flap group (p = 0.426) but higher in without flap group (p = 0.003). The patients with clinical Frey syndrome had significantly higher GSR values than the remaining patients. The SCM muscle flap was an effective method in preventing Frey's syndrome. Moreover, GSR test was highly sensitive and specific for diagnosis.

  5. 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.

  6. The genotoxic air pollutant 3-nitrobenzanthrone and its reactive metabolite N-hydroxy-3-aminobenzanthrone lack initiating and complete carcinogenic activity in NMRI mouse skin.

    PubMed

    Schmeiser, Heinz H; Fürstenberger, Gerhard; Takamura-Enya, Takeji; Phillips, David H; Arlt, Volker M

    2009-10-18

    3-Nitrobenzanthrone (3-NBA), a genotoxic mutagen found in diesel exhaust and ambient air pollution and its active metabolite N-hydroxy-3-aminobenzanthrone (N-OH-3-ABA) were tested for initiating and complete carcinogenic activity in the NMRI mouse skin carcinogenesis model. Both compounds were found to be inactive as either tumour initiators or complete carcinogens in mouse skin over a dose range of 25-400nmol. Topical application of 3-NBA and N-OH-3-ABA produced DNA adduct patterns in epidermis, detected by (32)P-postlabelling, similar to those found previously in other organs of rats and mice. 24h after a single treatment of 100nmol DNA adduct levels produced by 3-NBA (18+/-4 adducts/10(8) nucleotides) were 6 times lower than those by 7,12-dimethylbenz[a]anthracene (DMBA; 114+/-37 adducts/10(8) nucleotides). In contrast, identical treatment with N-OH-3-ABA resulted in adduct levels in the same range as with DMBA (136+/-25 adducts/10(8) nucleotides), indicating that initial DNA adduct levels do not parallel tumour initiating activity. When compounds were tested for tumour initiating activity by a single treatment followed by twice-weekly applications of TPA, DNA adducts formed by DMBA, but not by 3-NBA or N-OH-3-ABA, were still detectable 40weeks after treatment. When tested for activity as complete carcinogens by twice-weekly topical application, 3-NBA and N-OH-3-ABA produced identical DNA adduct profiles in mouse skin, with adducts still detectable after 40weeks. Only 3-NBA produced detectable adducts in other organs.

  7. Evaluation of a C-reactive protein latex agglutination detection test with sera from patients with sexually transmitted diseases.

    PubMed Central

    Schalla, W O; Arko, R J; Thompson, S E

    1984-01-01

    A total of 149 sera, including 79 pre- and posttreatment sera from 33 patients with disseminated gonococcal infections, 18 from patients with uncomplicated gonococcal infections, 6 from patients with pelvic inflammatory disease, 4 from patients with genital Chlamydia trachomatis infections, and 42 from normal volunteers, were examined for C-reactive protein with a latex agglutination C-reactive protein detection kit (Difco Laboratories, Detroit, Mich.). Results were quantitated with LC-Partigen C-reactive protein radial immuno-diffusion plates (Calbiochem-Behring, La Jolla, Calif.). Positive latex agglutination results were observed in all of the pretreatment sera and some of the posttreatment sera of patients with disseminated gonococcal infections and in two sera from patients with pelvic inflammatory disease, which corresponded to quantitative C-reactive protein levels in the radial immunodiffusion plates. C-reactive protein levels were not detectable in the serum samples from normal volunteers or patients with uncomplicated gonococcal infections or genital chlamydial infections. Positive latex agglutination occurred as early as 20 s in sera with high C-reactive protein levels, and all positive results were observed within 90 s of the 3-min test limit. Positive latex test results were obtained with C-reactive protein levels as low as 1 mg/dl (10 micrograms/ml). PMID:6440907

  8. Skin autoreactivity in Hashimoto's thyroiditis patients without urticaria: autologous serum skin test positivity correlation with thyroid antibodies, sonographical volume and grading.

    PubMed

    Turkoglu, Zafer; Zindanci, Ilkin; Turkoglu, Ozlem; Can, Burce; Kavala, Mukaddes; Tamer, Gonca; Ulucay, Vasfiye; Akyer, Erdal

    2012-01-01

    Recent studies have shown an association between anti-thyroid antibodies and autologous serum skin test (ASST) positive urticaria patients. However, a connection between thyroid and this reliable skin test for mast cell autoreactivity, ASST, has not been reported yet. We investigated ASST in patients with Hashimoto's thyroiditis (HT) without urticaria and compared the results with laboratory and sonographical findings of HT. 154 HT patients, 100 healthy volunteers without HT as a first control group and 46 patients with multinodular goitre but without autoimmune thyroid disease as a second control group underwent testing with ASST. ASST was applied to these groups according to two criteria, first as ASST(new): autologous serum red wheal response 1.5 mm bigger than negative control; second as ASST(old): serum red wheal response 5 mm bigger than negative control accepted as positive. Free triiodothyronine (fT3), free thyroxine (fT4), thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (anti-TPO) and thyroglobulin antibody (anti-Tg) levels were measured. ASST(old), ASST(new) scored positive in 51.3-60.4% of HT patients, with statistically significant differences. Thyroid volume grades were inversely proportional with ASST(old) and (new) positivity. Moderate (+) titers of anti-Tg in ASST(old) and (new) (+) cases were significantly higher than the same titers of anti-Tg in ASST(old) and (new) (-) cases. The prevalence of ASST positivity in HT patients was not affected by the following factors: gender, age at screening, laboratory measurements of thyroid function tests, anti-TPO antibodies and thyroid ultrasound (US) echogenicity. Positivity of ASST in HT has shown that there is a skin mast cell autoreactivity in HT patients independent of autoreactive chronic urticaria (ACU).

  9. Laboratory tests in support of the MSRE reactive gas removal system

    SciTech Connect

    Rudolph, J.C.; Del Cul, G.D.; Caja, J.; Toth, L.M.; Williams, D.F.; Thomas, K.S.; Clark, D.E.

    1997-07-01

    The Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory has been shut down since December 1969, at which time the molten salt mixture of LiF-BeF{sub 2}-ZrF{sub 4}-{sup 233}UF{sub 4} (64.5-30.3-5.0-0.13 mol%) was transferred to fuel salt drain tanks for storage. In the late 1980s, increased radiation in one of the gas lines from the drain tank was attributed to {sup 233}UF{sub 6}. In 1994 two gas samples were withdraw (from a gas line in the Vent House connecting to the drain tanks) and analyzed. Surprisingly, 350 mm Hg of F{sub 2}, 70 mm Hg of UF{sub 6}, and smaller amounts of other gases were found in both of the samples. To remote this gas from above the drain tanks and all of the associated piping, the reactive gas removal system (RGRS) was designed. This report details the laboratory testing of the RGRS, using natural uranium, prior to its implementation at the MSRE facility. The testing was performed to ensure that the equipment functioned properly and was sufficient to perform the task while minimizing exposure to personnel. In addition, the laboratory work provided the research and development effort necessary to maximize the performance of the system. Throughout this work technicians and staff who were to be involved in RGRS operation at the MSRE site worked directly with the research staff in completing the laboratory testing phase. Consequently, at the end of the laboratory work, the personnel who were to be involved in the actual operations had acquired all of the training and experience necessary to continue with the process of reactive gas removal.

  10. The associations between adolescent sleep, diurnal cortisol patterns and cortisol reactivity to dexamethasone suppression test.

    PubMed

    Pesonen, Anu-Katriina; Martikainen, Silja; Kajantie, Eero; Heinonen, Kati; Wehkalampi, Karoliina; Lahti, Jari; Strandberg, Timo; Räikkönen, Katri

    2014-11-01

    Information on the associations between objectively measured sleep and hypothalamic-pituitary-adrenal axis function in early adolescence is scarce. We examined associations between average sleep duration and quality (sleep efficiency and wake after sleep onset) over 8 days with actigraphs and (1) diurnal cortisol patterns and (2) cortisol reactivity to a low-dose (3 μg/kg) overnight dexamethasone suppression test (DST) in a birth cohort born in 1998 (N=265 participants, mean age 12.3 years, SD=0.5). We also explored (3) if sleep duration and quality were affected the nights after the DST exposure. Cortisol was measured during 2 days, and participants were exposed to dexamethasone in the evening of first day. In boys, short sleep duration was associated with higher cortisol upon awakening and lower cortisol awakening response (CAR; P<0.05 and P<0.01). Long sleep duration in boys associated with higher CAR (P<0.02). Lower sleep quality in boys associated with lower CAR, but fell slightly short of significance (P<0.06). In girls, no significant associations were detected. Sleep quantity and quality were not associated with responses to the DST. There were no effects of DST on sleep (P>0.15 in between-subject analyses). The average sleep patterns showed associations with diurnal cortisol patterns during early adolescence, but only in boys. Sleep was not associated with cortisol reactivity to DST and the exogenous corticosteroid exposure did not affect sleep significantly.

  11. 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

  12. 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.

  13. Assessment of latent tuberculosis infection in Takayasu arteritis with tuberculin skin test and Quantiferon-TB Gold test.

    PubMed

    Karadag, Omer; Aksu, Kenan; Sahin, Abdurrahman; Zihni, Figen Yargucu; Sener, Burcin; Inanc, Nevsun; Kalyoncu, Umut; Aydin, Sibel Zehra; Ascioglu, Sibel; Ocakci, Pinar Talu; Bilgen, Sule Apras; Keser, Gokhan; Inal, Vedat; Direskeneli, Haner; Calguneri, Meral; Ertenli, Ihsan; Kiraz, Sedat

    2010-09-01

    A possible relationship between Takayasu arteritis (TA) and tuberculosis (TB) has been suggested. An increased frequency of tuberculin skin test (TST) was observed in TA patients. Quantiferon-TB Gold test (QFT) is a new in vitro assay measuring interferon-gamma response to M. tuberculosis antigens and helpful in diagnosing latent TB infection. The aim of this study was to investigate latent TB infection among TA patients by the use of both TST and QFT Gold test. Ninety-four (male/female: 7/87) TA patients fulfilling ACR 1990 TA criteria from three different university hospitals in Turkey and 107 control subjects without inflammatory diseases were included in the study. Data about medical history (TA and TB) were collected for both groups. TST and QFT were performed. TST values > or =5 mm for TA patients and > or =15 mm for controls was accepted as TST positivity. Even though TA group was older (40 +/- 12 vs. 32 +/- 8, P < 0.001), there was no significant difference between TA patients and controls regarding demographic characteristics. Six TA patients and one control had a history of previous TB infection (P = 0.054). Although TST positivity was higher in TA group [55 patients (62.5%) vs. 24 controls (41.4%), P = 0.008], QFT positivity was similar between two groups [21 patients (22.3%) vs. 24 controls (22.4%), P > 0.05]. QFT was negative in two of six TA patients with previous TB history. Rate of latent TB infection in TA patients measured with QFT is no more than controls. QFT seems to be a good and favorable test compared with TST in detecting LTBI in TA.

  14. 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''.

  15. Helminths and skewed cytokine profiles increase tuberculin skin test positivity in Warao Amerindians.

    PubMed

    Verhagen, L M; Hermans, P W M; Warris, A; de Groot, R; Maes, M; Villalba, J A; del Nogal, B; van den Hof, S; Mughini Gras, L; van Soolingen, D; Pinelli, E; de Waard, J H

    2012-11-01

    The immune regulatory mechanisms involved in the acquisition of Mycobacterium tuberculosis infection in children are largely unknown. We investigated the influence of parasitic infections, malnutrition and plasma cytokine profiles on tuberculin skin test (TST) positivity in Warao Amerindians in Venezuela. Pediatric household contacts of sputum smear-positive tuberculosis (TB) cases were enrolled for TST, chest radiograph, plasma cytokine analyses, QuantiFERON-TB Gold In-Tube (QFT-GIT) testing and stool examinations. Factors associated with TST positivity were studied using generalized estimation equations logistic regression models. Of the 141 asymptomatic contacts, 39% was TST-positive. After adjusting for age, gender and nutritional status, TST positivity was associated with Trichuris trichiura infections (OR 3.5, 95% CI 1.1-11.6) and low circulating levels of T helper 1 (Th1) cytokines (OR 0.51, 95% CI 0.33-0.79). Ascaris lumbricoides infections in interaction with Th2- and interleukin (IL)-10-dominated cytokine profiles were positively associated with TST positivity (OR 3.1, 95% CI 1.1-8.9 and OR 2.4, 95% CI 1.04-5.7, respectively). A negative correlation of QFT-GIT mitogen responses with Th1 and Th2 levels and a positive correlation with age were observed (all p < 0.01). We conclude that helminth infections and low Th1 cytokine plasma levels are significantly associated with TST positivity in indigenous Venezuelan pediatric TB contacts.

  16. 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

  17. Cerebral vasomotor reactivity assessment using Transcranial Doppler and MRI with apnea test

    PubMed Central

    Herrera Campos, C.R.; Beltramini, G.C.; Avelar, W.M.; Lima, F.O.; Li, L.M.

    2016-01-01

    Differently from previous studies that used Transcranial Doppler (TCD) and functional MRI (fMRI) for cerebral vasomotor reactivity (CVR) assessment in patients with carotid stenosis (CS), we assessed CVR using an identical stimulus, the Breath-Holding Test (BHT). We included 15 patients with CS and 7 age-matched controls to verify whether fMRI responded differently to BHT between groups and to calculate the agreement rate between tests. For TCD, impaired CVR was defined when the mean percentage increase on middle cerebral artery velocities was ≤31% on 3 consecutive 30-s apnea intercalated by 4-min normal breathing intervals. For fMRI, the percent variation on blood oxygen level-dependent (BOLD) signal intensity in the lentiform nucleus (LN) ipsilateral to the CS (or both LNs for controls) from baseline breathing to apnea was measured. The Euclidian differences between the series of each subject and the series of controls and patients classified it into normal or impaired CVR. We found different percent variations on BOLD-signal intensities between groups (P=0.032). The agreement was good in Controls (85.7%; κ=0.69) and overall (77.3%; κ=0.54). We conclude that BHT was feasible for CVR assessment on fMRI and elicited different BOLD responses in patients and controls, with a good overall agreement between the tests. PMID:27783807

  18. Testing to determine relationship between explosive-contaminated sludge components and reactivity. Final report, June 1985-January 1987

    SciTech Connect

    Kristoff, F.T.; Ewing, T.W.; Johnson, D.E.

    1987-01-31

    Explosives manufacture and ammunition load, assembly and pack (LAP) operations result in the generation of explosives-contaminated wastewater. Over the years, the Department of the Army has used lagoons for treatment of these wastewaters by evaporation/percolation. These lagoons contain the remaining explosives-contaminated waters and sludges are listed as hazardous wastes under Federal regulations promulgated under the Resource Conservation and Recovery Act (RCRA). The basis for this listing is the assumed explosive reactivity of these wastes if subjected to a strong initiating source or if heated under confinement. The objective of this study was to investigate and define the reactivity of explosive-contaminated soils to flame and shock as a function of explosive composition using the Bureau of Mines (BOM) Zero Gap (shock) and Deflagration to Detonation Transition (DDT flame) tests. The resultant technical data will be used to define the reactivity of explosive-contaminated soil on the basis of compositional analyses. Extensive testing was conducted to investigate and define the reactivity of explosive-contaminated soils to flame and shock stimuli. From these tests, it is also concluded that explosive-contaminated soils can be diluted with virgin soil to reduce the total explosive content of < or = 12% and result in a composition which is not reactive in the BOM flame and shock tests.

  19. 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).

  20. 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.

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. Display of Antigens on Polyester Inclusions Lowers the Antigen Concentration Required for a Bovine Tuberculosis Skin Test.

    PubMed

    Parlane, Natalie A; Chen, Shuxiong; Jones, Gareth J; Vordermeier, H Martin; Wedlock, D Neil; Rehm, Bernd H A; Buddle, Bryce M

    2015-10-28

    The tuberculin skin test is the primary screening test for the diagnosis of bovine tuberculosis (TB), and use of this test has been very valuable in the control of this disease in many countries. However, the test lacks specificity when cattle have been exposed to environmental mycobacteria or vaccinated with Mycobacterium bovis bacille Calmette-Guérin (BCG). Recent studies showed that the use of three or four recombinant mycobacterial proteins, including 6-kDa early secretory antigenic target (ESAT6), 10-kDa culture filtrate protein (CFP10), Rv3615c, and Rv3020c, or a peptide cocktail derived from those proteins, in the skin test greatly enhanced test specificity, with minimal loss of test sensitivity. The proteins are present in members of the pathogenic Mycobacterium tuberculosis complex but are absent in or not expressed by the majority of environmental mycobacteria and the BCG vaccine strain. To produce a low-cost skin test reagent, the proteins were displayed at high density on polyester beads through translational fusion to a polyhydroxyalkanoate synthase that mediates the formation of antigen-displaying inclusions in recombinant Escherichia coli. Display of the proteins on the polyester beads greatly increased their immunogenicity, allowing for the use of very low concentrations of proteins (0.1 to 3 μg of mycobacterial protein/inoculum) in the skin test. Polyester beads simultaneously displaying all four proteins were produced in a single fermentation process. The polyester beads displaying three or four mycobacterial proteins were shown to have high sensitivity for detection of M. bovis-infected cattle and induced minimal responses in animals exposed to environmental mycobacteria or vaccinated with BCG.

  7. Multispecies reactive tracer test in an aquifer with spatially variable chemical conditions

    USGS Publications Warehouse

    Davis, J.A.; Kent, D.B.; Coston, J.A.; Hess, K.M.; Joye, J.L.

    2000-01-01

    A field investigation of multispecies reactive transport was conducted in a well-characterized, sand and gravel aquifer on Cape Cod, Massachusetts. The aquifer is characterized by regions of differing chemical conditions caused by the disposal of secondary sewage effluent. Ten thousand liters of groundwater with added tracers (Br, Cr(VI), and BDTA complexed with Pb, Zn, Cu, and Ni) were injected into the aquifer and distributions of the tracers were monitored for 15 months. Most of the tracers were transported more than 200 m; transport was quantified using spatial moments computed from the results of a series of synoptic samplings. Cr(VI) transport was retarded relative to Br; the retardation factor varied from 1.1 to 2.4 and was dependent on chemical conditions. At 314 days after the injection, dissolved Cr(VI) mass in the tracer cloud had decreased 85%, with the likely cause being reduction to Cr(III) in a suboxic region of the aquifer. Transport of the metal-EDTA complexes was affected by aqueous complexation, adsorption, and dissolution-precipitation reactions of Fe oxyhydroxide minerals in the aquifer sediments. Dissolved Pb-EDTA complexes disappeared from the tracer cloud within 85 days, probably due to metal exchange reactions with Fe and adsorbed Zn (present prior to the injection from contamination by the sewage effluent). About 30% of the Cu-EDTA complexes remained within the tracer cloud 314 days after injection, even though the thermodynamic stability of the Pb-EDTA complex is greater than Cu-EDTA. It is hypothesized that stronger adsorption of Pb2+ to the aquifer sediments causes the Pb-EDTA complex to disassociate to a greater degree than the Cu-EDTA complex. The mass of dissolved Zn-EDTA increased during the first 175 days of the tracer test to 140% of the mass injected, with the increase due to desorption of sewage-derived Zn. Dissolved Ni-EDTA mass remained nearly constant throughout the tracer test, apparently only participating in reversible

  8. [Age features of the dynamics of the oscillation amplitudes of the peripheral skin blood flow during the postocclusive reactive hyperemia].

    PubMed

    Tikhonova, I V; Tankanag, A V; Chemeris, N K

    2010-01-01

    The study of age-related changes of peripheral microhemodynamics was performed by laser Doppler flowmetry in 60 healthy volunteers. To determine the reaction of the microvascular system in response to short-term ischemia an occlusion test was used. To study the dynamics of the oscillation amplitudes of the peripheral blood flow the time-amplitude analysis on the basis of continuous adaptive wavelet filtration was used. It was found that the amplitudes of the oscillation in the range of heart rate in each age group reached its maxima with a delay after the occlusion stopping, whereas in the range of respiratory rhythm such delay was not observed. It is assumed that the formation ofhyperemic response to short-term ischemia occurs due to the preferential effect of arterio-arteriolar level, and the dynamics of the amplitudes in the range of respiratory rhythm reflects the devastation ofvenular level after occlusion stop. The observed age-related decreases of the maximum amplitudes in the range of myogenic, neurogenic and endothelial rhythms in response to shortterm ischemia demonstrate an age reduction limits of the peripheral blood flow regulation by related systems.

  9. Reconstructed epidermis and full-thickness skin for absorption testing: influence of the vehicles used on steroid permeation.

    PubMed

    Schäfer-Korting, Monika; Mahmoud, Ashraf; Lombardi Borgia, Simone; Brüggener, Barbara; Kleuser, Burkhard; Schreiber, Sylvia; Mehnert, Wolfgang

    2008-09-01

    A protocol for percutaneous absorption studies has been validated, based on the use of reconstructed human epidermis (RHE) and aqueous solutions of test substances. However, it is often the case that it is more-complex formulations of drugs or chemicals which will make contact with the skin surface. To investigate whether RHE and the reconstructed full-thickness skin model (FT-model) can be used to predict uptake from formulations, we compared the permeation of hydrocortisone and testosterone when applied in emulsion form and as a solution containing the penetration enhancer, ethanol. Human and pig skin and a non-cornified alveolar model served as references. The results were compared with steroid release from the formulations. The permeation rates of the steroids were ranked as: alveolar model > RHE > FT-model, pig skin > human skin. In accordance with the rapid hydrocortisone release from the formulations, the permeation rates of this steroid exceeded those of testosterone. Only minor differences were observed when comparing the testosterone formulations, in terms of release and permeation. However, the ranking of the permeation of the hydrocortisone formulations was: solution > w/o emulsion > o/w emulsion, which permitted the elucidation of penetration enhancing effects, which is not possible with drug release studies. Differences in penetration were most obvious with native skin and reconstructed tissues, which exhibited a well-developed penetration barrier. In conclusion, RHE and skin preparations may be useful in the development of topical dermatics, and in the framework of hazard analysis of toxic compounds and their various formulations.

  10. 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.

  11. Changes in Tuberculin Skin Test Positivity Over 20 Years in Periurban Shantytowns in Lima, Peru

    PubMed Central

    Martinez, Leonardo; Arman, Alyssa; Haveman, Nathan; Lundgren, Ashley; Cabrera, Lilia; Evans, Carlton A.; Pelly, Tom F.; Saito, Mayuko; Callacondo, David; Oberhelman, Richard; Collazo, Gisela; Carnero, Andrés M.; Gilman, Robert H.

    2013-01-01

    A cross-sectional, community-based study was performed in 2012 with 428 residents of periurban shantytowns in Lima, Peru to study risk factors for and changes in latent tuberculosis infection in age-stratified groups compared with our data from the same region in 1990 (N = 219) and 2005 (N = 103). Tuberculin skin test positivity in these communities was highly prevalent at 52% overall, increased with age (P < 0.01) and was similar to 2005 (53%) and 1990 (48%). From 1990 to 2012, the prevalence of tuberculin positivity decreased in 5–14 and 15–24 year old groups (to 17% and 34%, respectively, both P < 0.05). However, this may be explained by cessation of Bacille Calmette-Guérin revaccination during this period, because Bacille Calmette-Guérin revaccination doubled tuberculin positivity. Over the same 22-year period, tuberculin positivity in the ≥ 25 year old group remained high (71%, P = 0.3), suggesting that prevalent latent tuberculosis infection persists in the adult population despite improving medical care and socioeconomic development in this region. PMID:23878185

  12. Tuberculin skin test positivity in pediatric allogeneic BMT recipients and donors in Turkey.

    PubMed

    Tavil, Betul; Gulhan, Bora; Ozcelik, Ugur; Cetin, Mualla; Tezcan, Ilhan; Tuncer, Murat; Uckan, Duygu

    2007-06-01

    The preliminary study was performed to determine the frequency of tuberculin skin test (TST) positivity among 26 patients and their donors screened by TST to investigate whether tuberculin positivity of a recipient or donor influenced the rate of tuberculosis disease, transplant-related events, and to evaluate the effectiveness of isoniazide (INAH) prophylaxis administered to those with positive TST. The frequency of TST positivity was 23% (n = 6) among recipients and also 23% (n = 6) among donors. Two recipients and five donors with positive TST received INAH prophylaxis for six months. Our use of INAH prophylaxis in transplant patients was very conservative because of the risk of drug interaction. The transplantation procedure was not postponed for either recipient or donor TST positivity. Despite the high frequency of tuberculosis in our country, we have not detected any case of tuberculosis in our center, either among the purified protein derivative-screened (n = 26) or non-screened (n = 128) patients except for disseminated tuberculosis infection because of BCG vaccination in two patients with severe combined immunodeficiency. In conclusion, TST positivity in either recipient or donor may not be a contraindication for bone marrow transplantation and the procedure may not be postponed. Pretransplantation TST screening may be needed in countries where tuberculosis is common in the general population.

  13. The effect of allergic rhinitis with positive skin prick test on choroidal thickness.

    PubMed

    Yenigun, Alper; Elbay, Ahmet; Dogan, Remzi; Ozturan, Orhan; Ozdemir, Mehmet Hakan

    2017-03-06

    Allergic rhinitis is an inflammatory disease that develops through immunoglobulin E in the rhino-ocular mucosa due to allergy. The main symptoms are runny nose, nasal congestion, sneezing and itchy nose. This study was designed to investigate the effect of allergic rhinitis on choroidal thickness. This study was planned as a case-control study. This study performed in a tertiary referral center. The study included 61 patients with allergic rhinitis and 35 healthy subjects. Patients in both groups underwent skin prick test. In allergic rhinitis patients and healthy persons; subfoveal, temporal and nasal choroidal thickness measurement was performed. The choroidal thicknesses were measured without pupil dilation using the Spectralis Optical Coherence Tomography. In the subfoveal and temporal region, choroidal tissue was followed up significantly thicker in allergic rhinitis patients statistically compared to healthy persons (p = 0.031, p = 0.049). However, no significant difference was followed up between the nasal choroidal thickness measurements statistically (p = 0.54). Runny nose (67.2%), sneeze (65.5%), stuffiness (62.2%), itching of the nose (40.9%), and nasal discharge (21.3%) complaints were observed significantly higher in the group having allergic rhinitis. The effect of allergic rhinitis on choroidal thickness were assessed and compared with the control group. Our study revealed that there was significant association between increased choroidal thickness and allergic rhinitis. Allergic sensitivity may play an important role in increased choroidal thickness.

  14. Crude 4-methylcyclohexanemethanol (MCHM) did not cause skin irritation in humans in 48-h patch test.

    PubMed

    Monnot, Andrew D; Novick, Rachel M; Paustenbach, Dennis J

    2017-03-13

    Crude 4-methylcyclohexanemethanol (MCHM) is an industrial chemical used to wash and clean coal. On January 9th, 2014 approximately 10,000 gallons of a mixture containing crude MCHM were released into the Elk River near Charleston, West Virginia, contaminating the local water supply. Following the spill, residents reported numerous health complaints, and sought medical attention for ailments including rashes and itching. The relationship between the complaints and the spill were unknown, as such symptoms are reported frequently in the background. In this study, the primary irritation potential of crude MCHM was evaluated in 206 individuals who underwent 48 hour semi-occluded patch testing. MCHM concentrations assessed in this study were 1, 5, 15, and 100 ppm. No appreciable skin reactions were observed in individuals at any concentration. Three of the five concentrations evaluated were above the highest measured concentration of MCHM in the tap water of residents in West Virginia (3.7 ppm). The results of this study suggest that crude MCHM would not be a dermal irritant for the vast majority, if not all, potentially exposed persons at the concentrations in the water reported after the spill.

  15. 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.

  16. Open source software implementation of an integrated testing strategy for skin sensitization potency based on a Bayesian network.

    PubMed

    Pirone, Jason R; Smith, Marjolein; Kleinstreuer, Nicole C; Burns, Thomas A; Strickland, Judy; Dancik, Yuri; Morris, Richard; Rinckel, Lori A; Casey, Warren; Jaworska, Joanna S

    2014-01-01

    An open-source implementation of a previously published integrated testing strategy (ITS) for skin sensitization using a Bayesian network has been developed using R, a free and open-source statistical computing language. The ITS model provides probabilistic predictions of skin sensitization potency based on in silico and in vitro information as well as skin penetration characteristics from a published bioavailability model (Kasting et al., 2008). The structure of the Bayesian network was designed to be consistent with the adverse outcome pathway published by the OECD (Jaworska et al., 2011, 2013). In this paper, the previously published data set (Jaworska et al., 2013) is improved by two data corrections and a modified application of the Kasting model. The new data set implemented in the original commercial software package and the new R version produced consistent results. The data and a fully documented version of the code are publicly available (http://ntp.niehs.nih.gov/go/its).

  17. 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.

  18. 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.

  19. Quantitative thermal sensory testing and sympathetic skin response in primary Restless legs syndrome - A prospective study on 57 Indian patients.

    PubMed

    Shukla, Garima; Goyal, Vinay; Srivastava, Achal; Behari, Madhuri

    2012-10-01

    Patients with restless leg syndrome present with sensory symptoms similar to peripheral neuropathy. While there is evidence of abnormalities of dopaminergic pathways, the peripheral nervous system has been studied infrequently. We studied conventional nerve conduction studies, quantitative thermal sensory testing and sympathetic skin response in 57 patients with primary restless leg syndrome. Almost two third patients demonstrated abnormalities in the detailed testing of the peripheral nervous system. Sbtle abnormalities of the peripheral nervous system may be more common than previously believed.

  20. 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).

  1. Association between tuberculin skin test result and clinical presentation of tuberculosis disease

    PubMed Central

    2013-01-01

    Background The tuberculin skin test (TST) is used to test for latent tuberculosis (TB) infection and support the diagnosis of active TB. However, little is known about the relationship between the TST result and the clinical presentation of TB disease. Methods We analyzed US TB surveillance data, 1993–2010, and used multinomial logistic regression to calculate the association between TST result (0–4 mm [negative], 5–9 mm, 10–14 mm, and ≥ 15 mm) and clinical presentation of disease (miliary, combined pulmonary and extrapulmonary, extrapulmonary only, non-cavitary pulmonary, and cavitary pulmonary). For persons with pulmonary disease, multivariate logistic regression was used to calculate the odds of having acid-fast bacilli (AFB) positive sputum. Results There were 64,238 persons with culture-confirmed TB included in the analysis, which was stratified by HIV status and birthplace (US- vs. foreign-born). Persons with a TST ≥ 15 mm were less likely to have miliary or combined pulmonary and extrapulmonary disease, but more likely to have cavitary pulmonary disease than non-cavitary pulmonary disease. Persons with non-cavitary pulmonary disease with a negative TST were significantly more likely to have AFB positive sputum. Conclusions Clinical presentation of TB disease differed according to TST result and persons with a negative TST were more likely to have disseminated disease (i.e., miliary or combined pulmonary and extrapulmonary). Further study of the TST result may improve our understanding of the host-pathogen relationship in TB disease. PMID:24093965

  2. 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

  3. High emotional reactivity toward an experimenter affects participation, but not performance, in cognitive tests with common marmosets (Callithrix jacchus).

    PubMed

    Schubiger, Michèle N; Wüstholz, Florian L; Wunder, André; Burkart, Judith M

    2015-05-01

    When testing primates with cognitive tasks, it is usually not considered that subjects differ markedly in terms of emotional reactivity toward the experimenter, which potentially affects a subject's cognitive performance. We addressed this issue in common marmosets (Callithrix jacchus), a monkey species in which males tend to show stronger emotional reactivity in testing situations, whereas females have been reported to outperform males in cognitive tasks. In a two-phase experiment, we first quantified the emotional reactivity of 14 subjects toward four different experimenters performing a standardized behavioral action sequence and then assessed whether and how it affected the subjects' participation and performance in a subsequent object permanence task. A test session was terminated if a subject refused to make a choice in four consecutive trials. Highly emotionally aroused individuals, particularly males, were less likely to participate in the cognitive task and completed fewer trials. However, whenever they did participate and were attentive to the task, their performance was not affected. Our results suggest that differences in emotional reactivity toward an experimenter have no major impact on cognitive performance if strict criteria are applied on when to abandon a test session and if performance is corrected for attention to the test procedure. Furthermore, they suggest that the reported sex differences in cognitive performance in marmosets may be owing to motivational and attentional factors, rather than a difference in cognitive ability per se.

  4. 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.

  5. 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.

  6. COPD assessment test score and serum C-reactive protein levels in stable COPD patients

    PubMed Central

    Kang, Hyung Koo; Kim, Kang; Lee, Hyun; Jeong, Byeong-Ho; Koh, Won-Jung; Park, Hye Yun

    2016-01-01

    Background An eight-item questionnaire of the COPD assessment test (CAT) is widely used to quantify the impact of COPD on the patient’s health status. C-reactive protein (CRP) is associated with disease severity and adverse health outcomes of patients with COPD. This study aimed to evaluate the relationship between CAT score and serum CRP levels in stable COPD patients. Methods We evaluated the medical records of 226 patients with CAT and serum CRP measured within a week at Samsung Medical Center between October 2013 and October 2015. Results Serum CRP levels had a significantly positive relationship with CAT score (Spearman’s r=0.20, P=0.003). Patients with elevated serum CRP levels (>0.3 mg/dL) were significantly more likely to have CAT scores of ≥14. The adjusted odds ratio for elevated serum CRP levels in total CAT score was 1.06 (95% confidence interval, 1.02–1.09). Among CAT components, cough (adjusted P=0.005), phlegm (adjusted P=0.001), breathlessness going up hills/stairs (adjusted P=0.005), low confidence leaving home (adjusted P=0.002), and feeling low in energy (adjusted P=0.019) were independently associated with elevated serum CRP levels. Conclusion In stable COPD patients, serum CRP levels were independently associated with total CAT score and CAT components related to respiratory symptoms, confidence leaving home, and energy. PMID:27994452

  7. Quantitative capillary reversed passive latex agglutination test for C-reactive protein (CRP) in the dog.

    PubMed

    Tagata, K; Yokoyama, S; Ginbo, T; Honda, M; Okimura, T; Odakura, M; Nomura, M; Yamamoto, S

    1996-01-01

    A capillary reversed passive latex agglutination test (capillary RPLA) was developed which allows quantification of serum C-reactive protein (CRP) within approximately 15 min. The logarithmic regression line (calibration curve) obtained after measuring each CRP concentration three times in twofold dilutions of a standard canine serum containing 222 micrograms/ml of CRP was y = 6.394 + 0.030x (r = 0.995). Capillary RPLA permitted quantification of CRP in the range 6.9-222 micrograms/ml. The coefficients of variation ranged from 10.28% to 12.40%. The recovery rates (percentage recovery) of CRP by capillary RPLA were within the range 87% to 106%. On measuring the CRP concentrations in sera from 78 dogs by capillary RPLA, single radial immunodiffusion (SRID) and enzyme-linked immunosorbent assay (ELISA), close correlations were demonstrated between SRID and capillary RPLA (y = 7.250 + 1.109x, r = 0.978), between SRID and ELISA (y = 3.042 + 1.059x, r = 0.967), and between capillary RPLA and ELISA (y = 1.778 + 0.929x, r = 0.962). Capillary RPLA may be considered useful as a routine biochemical technique for measurement of serum CRP concentration in the dog.

  8. 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.

  9. 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.

  10. Release of nickel ions from stainless steel alloys used in dental braces and their patch test reactivity in nickel-sensitive individuals.

    PubMed

    Jensen, Christian Stab; Lisby, Steen; Baadsgaard, Ole; Byrialsen, Kirsten; Menné, Torkil

    2003-06-01

    Nickel ions leached in sufficient quantities from nickel-containing alloys may induce nickel sensitization or elicit allergic contact dermatitis. Nickel-containing stainless steel alloys are generally considered safe for nickel-sensitive individuals to use. The study summarized in this paper investigated 3 parameters. First, the release of nickel was estimated in artificial saliva and sweat from 4 different stainless steel alloys frequently used in dental braces. Second, in a pilot study, oral mucosa cells harvested from 3 dental patients before and after the attachment of dental braces were analysed for possible nickel content. Third, patch test reactivity of the 4 stainless steel alloys was tested on 31 nickel-sensitive subjects. All 4 stainless steel alloys released small amounts of nickel ions into artificial saliva (<0.13 micro g/cm2/week) and artificial sweat (<0.05 micro g/cm2/week), but no measurable amounts of nickel were found in any of the oral mucosa samples. None of the 31 nickel-sensitive subjects reacted to patch testing with the 4 stainless steel alloys, indicating that these stainless steel alloys would be safe to use in direct and prolonged contact with the skin.

  11. Evaluation of Leishmanin Skin Test Reaction in Different Variants of Cutaneous Leishmaniasis

    PubMed Central

    Sadeghian, Giti; Ziaei, Hengameh; Bidabadi, Leila Shirani; Nilforoushzadeh, Mohammad Ali

    2013-01-01

    Introduction: Cutaneous leishmaniasis (CL) is a parasitic disease which has different clinical forms. The aim of this study is to compare the response to leishmanin skin test (LST) in three forms of CL including plaque type, lupoid type, and sporotrichoid type. Materials and Methods: This was a descriptive cross-sectional study. The patients enrolled in this study had three clinical forms of CL confirmed by positive smear of their lesions and then LST was performed for them. Results were categorized as negative (0-5 mm induration), positive (6-14 mm), and strongly positive (≥15 mm). The data were documented in the patients’ files and analyzed with SPSS windows software version 16 (Inc.Chicago, USA). Results: 200 patients were enrolled in the study. In the group with plaque type, 86% had a positive LST, 13.3% were negative, and 0.7% were strongly positive. In the lupoid group, these figures were 45.8%, 8.4%, 45.8%, respectively. In the sporotrichoid group, LST was positive in 27.3%, negative in 72.7%, and none of the patients had a strongly positive reaction (P < 0.05). Discussion: The most of the positive LST were belong to plaque and lupoid groups, the most of strongly positive were belong to lupoid, and the most of negative LST were related with sporotrichoid type. Conclusion: It can be suggested that lupoid and sporotrichoid types of CL are parts of a continuous spectrum of the disease with an enhanced cellular immunity in lupoid form and a decreased state in sporotrichoid type. PMID:23723480

  12. Assessment of endothelial and neurovascular function in human skin microcirculation.

    PubMed

    Roustit, Matthieu; Cracowski, Jean-Luc

    2013-07-01

    Peripheral microvascular dysfunction has been described in many physiological and pathological conditions. Owing to its accessibility, the cutaneous microcirculation provides a unique index of microvascular function. Skin microvascular function has therefore been proposed as a prognostic marker or for evaluating the effect of drugs on the microcirculation. Various reactivity tests, coupled with techniques measuring skin blood flux, are used to non-invasively explore both endothelial and neurovascular microvascular functioning in humans. We review the advantages and limitations of the main reactivity tests, including post-occlusive reactive hyperemia, local thermal hyperemia, pressure-induced vasodilation, and iontophoresis of vasodilators, combined with measurement techniques such as laser Doppler and laser speckle contrast imaging. Recent advances in our comprehension of the physiological pathways underlying these reactivity tests, as well as technological developments in microcirculation imaging, have provided reliable and reproducible tools for studying the microcirculation.

  13. 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.

  14. Reactivity Initiated Accident Simulation to Inform Transient Testing of Candidate Advanced Cladding

    SciTech Connect

    Brown, Nicholas R; Wysocki, Aaron J; Terrani, Kurt A

    2016-01-01

    Abstract. Advanced cladding materials with potentially enhanced accident tolerance will yield different light water reactor performance and safety characteristics than the present zirconium-based cladding alloys. These differences are due to different cladding material properties and responses to the transient, and to some extent, reactor physics, thermal, and hydraulic characteristics. Some of the differences in reactors physics characteristics will be driven by the fundamental properties (e.g., absorption in iron for an iron-based cladding) and others will be driven by design modifications necessitated by the candidate cladding materials (e.g., a larger fuel pellet to compensate for parasitic absorption). Potential changes in thermal hydraulic limits after transition from the current zirconium-based cladding to the advanced materials will also affect the transient response of the integral fuel. This paper leverages three-dimensional reactor core simulation capabilities to inform on appropriate experimental test conditions for candidate advanced cladding materials in a control rod ejection event. These test conditions are using three-dimensional nodal kinetics simulations of a reactivity initiated accident (RIA) in a representative state-of-the-art pressurized water reactor with both nuclear-grade iron-chromium-aluminum (FeCrAl) and silicon carbide based (SiC-SiC) cladding materials. The effort yields boundary conditions for experimental mechanical tests, specifically peak cladding strain during the power pulse following the rod ejection. The impact of candidate cladding materials on the reactor kinetics behavior of RIA progression versus reference zirconium cladding is predominantly due to differences in: (1) fuel mass/volume/specific power density, (2) spectral effects due to parasitic neutron absorption, (3) control rod worth due to hardened (or softened) spectrum, and (4) initial conditions due to power peaking and neutron transport cross sections in the

  15. The Effect of Variable Geochemical Conditions on the Reactive Transport of U(VI) in Small Scale Tracer Tests

    NASA Astrophysics Data System (ADS)

    Curtis, G. P.; Fox, P.; Kohler, M.; Davis, J. A.

    2005-12-01

    Small-scale tracer tests were conducted to evaluate the effect of variable geochemical conditions on the reactive transport of U(VI). The tracer tests were conducted in a shallow alluvial aquifer downgradient from a former uranium mill and a tailings disposal area near Naturita, CO. The U(VI) concentration in the groundwater at the tracer test site was approximately 5 μM, the alkalinity was 8.5 meq/L and the pH was approximately 7.1. Previous studies at the site demonstrated the U(VI) was most sensitive to the alkalinity and least sensitive to the pH values relative to the range of measured values. Uranium migration tests were conducted on a scale of 1-2.5 m and considered variable U(VI) and alkalinity and included Br as an inert tracer. The tracer tests demonstrated that the sediment readily released U(VI) even after many years of contact with the contaminated groundwater suggesting the U(VI) migration is controlled by adsorption reactions. Reactive transport simulations used a surface complexation model developed independently from laboratory bench scale studies to simulate adsorption. The reactive transport simulations gave good predictions of the observed breakthrough of U(VI) when the advection and dispersion parameters were fitted to Br breakthrough. Field studies also included several single well push-pull tests that were conducted at increased and decreased U(VI) and alkalinity values. Reactive transport simulations of these experiments will be presented and compared with the tracer tests simulations.

  16. 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 ...

  17. Development of an in vitro modified skin absorption test for the investigation of the follicular penetration pathway of caffeine.

    PubMed

    Trauer, S; Lademann, J; Knorr, F; Richter, H; Liebsch, M; Rozycki, C; Balizs, G; Büttemeyer, R; Linscheid, M; Patzelt, A

    2010-01-01

    The Organization for Economic Cooperation and Development (OECD) recommends caffeine as a reference substance for in vitro skin absorption tests using Franz diffusion cells (FDC). However, it has not been possible to investigate the follicular penetration pathway using this method until now. The aim of this study was to develop a technique to allow the examination of the follicular penetration pathway of a substance penetrating into the skin. The OECD standard method was therefore combined with the follicle closing technique (FCT), an established in vivo method. By using test skin of varying follicular densities, different penetration values were obtained for the test substance caffeine. The follicular penetration rate was determined by an indirect calculation after modifying the in vivo FCT for use in the in vitro FDC. This method is the first to allow the differentiation of penetration pathways by combining the OECD standard method (using the FDC) and the FCT. Caffeine showed a surprisingly high rate of penetration through the follicular shunts in vitro.

  18. Full-field bulge test for planar anisotropic tissues: part I--experimental methods applied to human skin tissue.

    PubMed

    Tonge, Theresa K; Atlan, Lorre S; Voo, Liming M; Nguyen, Thao D

    2013-04-01

    The nonlinear anisotropic properties of human skin tissue were investigated using bulge testing. Full-field displacement data were obtained during testing of human skin tissues procured from the lower back of post-mortem human subjects using 3-D digital image correlation. To measure anisotropy, the dominant fiber direction of the tissue was determined from the deformed geometry of the specimen. Local strains and stress resultants were calculated along both the dominant fiber direction and the perpendicular direction. Variation in anisotropy and stiffness was observed between specimens. The use of stress resultants rather than the membrane stress approximation accounted for bending effects, which are significant for a thick nonlinear tissue. Of the six specimens tested, it was observed that specimens from older donors exhibited a stiffer and more isotropic response than those from younger donors. It was seen that the mechanical response of the tissue was negligibly impacted by preconditioning or the ambient humidity. The methods presented in this work for skin tissue are sufficiently general to be applied to other planar tissues, such as pericardium, gastrointestinal tissue, and fetal membranes. The stress resultant-stretch relations will be used in a companion paper to obtain material parameters for a nonlinear anisotropic hyperelastic model.

  19. 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.

  20. 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

  1. 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...

  2. Interparental Aggression and Children’s Adrenocortical Reactivity: Testing an Evolutionary Model of Allostatic Load

    PubMed Central

    Davies, Patrick T.; Sturge-Apple, Melissa L.; Cicchetti, Dante

    2011-01-01

    Guided by an evolutionary model of allostatic load (Korte, Koolhaas, Wingfield, & McEwen, 2005), this study examined the hypothesis that the association between interparental aggression and subsequent changes in children’s cortisol reactivity to interparental conflict is moderated by their temperamental dispositions. Participants of the multi-method, longitudinal study included 201 two-year-old toddlers and their mothers. These children experienced elevated levels of aggression between parents. Consistent with the theory, the results indicated that interparental aggression predicted greater cortisol reactivity over a one year period for children who exhibited high levels of temperamental inhibition and vigilance. Conversely, for children with bold, aggressive temperamental characteristics, interparental aggression was marginally associated with diminished cortisol reactivity. Further underscoring its implications for allostatic load, increasing cortisol reactivity over the one year span was related to concomitant increases in internalizing symptoms but decreases in attention and hyperactivity difficulties. In supporting the evolutionary conceptualization, these results further supported the relative developmental advantages and costs associated with escalating and dampened cortisol reactivity to interparental conflict. PMID:21756433

  3. The Clinical Usefulness of Tuberculin Skin Test versus Interferon-Gamma Release Assays for Diagnosis of Latent Tuberculosis in HIV Patients: A Meta-Analysis

    PubMed Central

    Ayubi, Erfan; Doosti-Irani, Amin; Sanjari Moghaddam, Ali; Sani, Mohadeseh; Nazarzadeh, Milad; Mostafavi, Ehsan

    2016-01-01

    Background Accurate diagnosis of latent tuberculosis infection (LTBI) is becoming increasingly concerning due to the increasing the HIV epidemic, which have increased the risk for reactivation to active tuberculosis (TB) infection. LTBI is diagnosed by tuberculin skin test (TST) and interferon-gamma release assays (IGRAs). Objectives The aim of the present study was to conduct a meta-analysis of published papers on the agreement (kappa) between TST and QuantiFERON-TB Gold In-Tube (QFT-GIT) tests for diagnosis of LTBI in HIV patient. Methods Electronic databases including PubMed/Medline, Elsevier/Scopus and Embase/Ovid were reviewed up Jan. 2016. We performed a random effect model meta-analysis for estimation of pooled Kappa between the two methods of diagnosis. Meta regression was used for assessing potential heterogeneity and Egger’s test was used for assessing small study effect and publication bias. Results The initial search strategy produced 6744 records. Of them, 23 cross-sectional studies met the inclusion criteria and 20 studies entered in meta-analysis. The pooled kappa was and prevalence-adjusted and bias-adjusted kappa (PABAK) were 0.37 (95% CI: 0.28, 0.46) and 0.59 (0.49, 0.69). The discordance of TST-/QFT-GIT+ was more than TST+/QFT-GIT-. Kappa estimate between two tests was linearly associated with age and prevalence index and inversely associated with bias index. Conclusion Fair agreement between TST and QFT-GIT makes it difficult to know whether TST is as useful as the QFT-GIT in HIV-infected patients. The higher discordance of TST-/QFT-GIT+ in compared to TST+/QFT-GIT- can induce the higher sensitivity of QFT-GIT for diagnosis LTBI in HIV patients. Disagreement between two tests can be influenced by error in measurements and prevalence of HIV. PMID:27622293

  4. FROZEN RAW FOODS AS SKIN-TESTING MATERIALS—Further Studies of Use in Cases of Allergic Disorders

    PubMed Central

    Ancona, Giacomo R.; Schumacher, Irwin C.

    1954-01-01

    In further studies on the use of frozen raw food as skin-testing material in patients with allergic disorders, the results of previous work were confirmed in a greater number of subjects using a larger number of foods: Tests with frozen raw foods by the scratch method induce true positive reactions of a larger size and in greater frequency than the corresponding commercial extracts by either the scratch or the intracutaneous method. Storage in the frozen state for several years does not affect the antigenic potency of the materials. The frozen preparations have caused no harmful effects in the subjects, are free from irritant properties, and are not urticariogenic. PMID:13126823

  5. A new method to test the effectiveness of sunscreen ingredients in a novel nano-surface skin cell mimic.

    PubMed

    Krishnan, Rajagopal; Elmets, Craig A; Nordlund, Thomas M

    2006-01-01

    Photophysical properties of sunscreens are commonly studied in solvent media, which do not mimic the skin, or in complex artificial skin systems, which are difficult to handle. In an earlier study, we showed that polystyrene nanosphere suspensions mimic the mixed polarity environment of skin cell systems. This paper presents a new method to quantify the effectiveness of sunscreens in the polystyrene nanosphere environment. This method utilizes the intrinsic UV-B fluorescence of polystyrene nanospheres. We studied three UV-B sunscreens by this new method and compared their extinction coefficients with observed values in solvent. The values follow the trend observed in solvents, but the ratio of their extinction coefficient in solvent to the value obtained by this new method is 1.3-1.8 instead of 1. This difference might be caused by the mixed polarity or the microgeometry of the nanosphere system. Regardless of the difference in the extinction coefficients, this new system can be used to test hundreds of chemicals for their sunscreening potential in a cost-effective way. One marked advantage of this new method is its ability to test both hydrophobic and hydrophilic sunscreening chemicals in the same environment. This is virtually impossible for current solvent-based models, which require different solvents for hydrophobic and hydrophilic chemicals. The new method also allows the simultaneous evaluation of a host of photophysical properties of sunscreening chemicals.

  6. Skin irritation to glass wool or continuous glass filaments as observed by a patch test among human Japanese volunteers.

    PubMed

    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.

  7. 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.

  8. 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

  9. Purifying and Testing Gecko Skin Compounds, a Promising Attractant for Small Brown Treesnakes

    DTIC Science & Technology

    2012-03-13

    that is the case, applying the scent to a more natural- looking (i.e., lizard -like) object may render a stronger and more uniform (across snake ...to other islands. Attractants are particularly needed for <>mall snakes . which are resistant to current control techniques. We extracted skin...compounds from gcckos ( Hemidactylus frcnatus). a preferred prey of the small snakes . and used bioassays to identify which of the successively more purified

  10. Integration, Testing, and Analysis of Multispectral Imager on Small Unmanned Aerial System for Skin Detection

    DTIC Science & Technology

    2014-03-01

    1.8 Preview Chapter II explores the background literature for skin detection , SUAS, methods for vision processing, and metrics for imagery ...subpixel domain (Morales, 2012). Proper spatial pixel density is essential for a sensor and target detection methods . When targeting spectral...sensor for automated target detection , thus the equation has been modified to work with aberrated imagery (Thurman & Fienup, 2010). /GSD pR f

  11. 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

  12. 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.

  13. Skin sensitisation--moving forward with non-animal testing strategies for regulatory purposes in the EU.

    PubMed

    Basketter, David; Alépée, Nathalie; Casati, Silvia; Crozier, Jonathan; Eigler, Dorothea; Griem, Peter; Hubesch, Bruno; de Knecht, Joop; Landsiedel, Robert; Louekari, Kimmo; Manou, Irene; Maxwell, Gavin; Mehling, Annette; Netzeva, Tatiana; Petry, Thomas; Rossi, Laura H

    2013-12-01

    In a previous EPAA-Cefic LRI workshop in 2011, issues surrounding the use and interpretation of results from the local lymph node assay were addressed. At the beginning of 2013 a second joint workshop focused greater attention on the opportunities to make use of non-animal test data, not least since a number of in vitro assays have progressed to an advanced position in terms of their formal validation. It is already recognised that information produced from non-animal assays can be used in regulatory decision-making, notably in terms of classifying a substance as a skin sensitiser. The evolution into a full replacement for hazard identification, where the decision is not to classify, requires the generation of confidence in the in vitro alternative, e.g. via formal validation, the existence of peer reviewed publications and the knowledge that the assay(s) are founded on key elements of the Adverse Outcome Pathway for skin sensitisation. It is foreseen that the validated in vitro assays and relevant QSAR models can be organised into formal testing strategies to be applied for regulatory purposes by the industry. To facilitate progress, the European Partnership for Alternative Approaches to animal testing (EPAA) provided the platform for cross-industry and regulatory dialogue, enabling an essential and open debate on the acceptability of an in vitro based integrated strategy. Based on these considerations, a follow up activity was agreed upon to explore an example of an Integrated Testing Strategy for skin sensitisation hazard identification purposes in the context of REACH submissions.

  14. 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.

  15. 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

  16. Skin Diseases: Skin Health and Skin Diseases

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Skin Health and Skin Diseases Past Issues / Fall 2008 Table of Contents ... acne to wrinkles Did you know that your skin is the largest organ of your body? It ...

  17. 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).

  18. Discordance between Aeroallergen Specific Serum IgE and Skin Testing in Children < 4 years of age

    PubMed Central

    de Vos, Gabriele; Nazari, Ramin; Ferastraoaru, Denisa; Parikh, Purvi; Geliebter, Rebecca; Pichardo, Yikania; Wiznia, Andrew; Rosenstreich, David

    2015-01-01

    Background Atopic sensitization to aeroallergens in early life has been shown to be a strong risk factor for developing persisting asthma in young children with recurrent wheeze. Objective The aim of this study was to assess the yield of skin prick test (SPT) compared to allergen specific serum IgE testing (sIgE) at identifying aeroallergen sensitization in atopic children < 4 years of age. Methods Concordance between SPT (Greer Laboratories, ComforTen™) and allergen specific sIgE (Immulite 2000™) for 7 common aeroallergens was analyzed in forty atopic inner-city children, 18–48 months of age (mean 36 +/− 9 months) with recurrent wheezing, family history of asthma and/or eczema. Results In 80% of children one or more allergen sensitizations would have been missed if only SPT had been performed, and in 38% of children one or more sensitizations would have been missed if only serum IgE testing had been performed. Agreement and between SPT and sIgE test was fair for most allergens (kappa between −0.04 and 0.50), as was correlation between sIgE levels and SPT grade (rho between 0.21 and 0.55). Children with high total sIgE (≥300 kU/l) were more likely to have sIgE positive tests with negative corresponding skin test (p=0.025). Conclusions Our study showed significant discordance between allergen specific SPT and sIgE testing results for common aeroallergens, suggesting that both SPT and sIgE testing should be done when diagnosing allergic sensitization in young children at high risk of asthma. PMID:23706713

  19. 12-OH-nevirapine sulfate, formed in the skin, is responsible for nevirapine-induced skin rash.

    PubMed

    Sharma, Amy M; Novalen, Maria; Tanino, Tadatoshi; Uetrecht, Jack P

    2013-05-20

    Nevirapine (NVP) treatment is associated with a significant incidence of skin rash in humans, and it also causes a similar immune-mediated skin rash in Brown Norway (BN) rats. We have shown that the sulfate of a major oxidative metabolite, 12-OH-NVP, covalently binds in the skin. The fact that the sulfate metabolite is responsible for covalent binding in the skin does not prove that it is responsible for the rash. We used various inhibitors of sulfation to test whether this reactive sulfate is responsible for the skin rash. Salicylamide (SA), which depletes 3'-phosphoadenosine-5'-phosphosulfate (PAPS) in the liver, significantly decreased 12-OH-NVP sulfate in the blood, but it did not prevent covalent binding in the skin or the rash. Topical application of 1-phenyl-1-hexanol, a sulfotransferase inhibitor, prevented covalent binding in the skin as well as the rash, but only where it was applied. In vitro incubations of 12-OH-NVP with PAPS and cytosolic fractions from the skin of rats or from human skin also led to covalent binding that was inhibited by 1-phenyl-1-hexanol. Incubation of 12-OH-NVP with PAPS and sulfotransferase 1A1*1, a human isoform that is present in the skin, also led to covalent binding, and this binding was also inhibited by 1-phenyl-1-hexanol. We conclude that salicylamide did not deplete PAPS in the skin and was unable to prevent covalent binding or the rash, while topical 1-phenyl-1-hexanol inhibited sulfation of 12-OH-NVP in the skin and did prevent covalent binding and the rash. These results provide definitive evidence that 12-OH-NVP sulfate formed in skin is responsible for NVP-induced skin rashes. Sulfotransferase is one of the few metabolic enzymes with significant activity in the skin, and it may be responsible for the bioactivation of other drugs that cause skin rashes.

  20. Reliability of a Field Test of Defending and Attacking Agility in Australian Football and Relationships to Reactive Strength.

    PubMed

    Young, Warren B; Murray, Mitch P

    2017-02-01

    Young, WB and Murray, MP. Reliability of a field test of defending and attacking agility in Australian football and relationships to reactive strength. J Strength Cond Res 31(2): 509-516, 2017-Defending and attacking agility tests for Australian football do not exist, and it is unknown whether any physical qualities correlate with these types of agility. The purposes of this study were to develop new field tests of defending and attacking agility for Australian Rules football, to determine whether they were reliable, and to describe the relationship between the agility tests to determine their specificity. Because the reactive strength (RS) of the lower limb muscles has been previously correlated with change-of-direction speed, we also investigated the relationship between this quality and the agility tests. Nineteen male competitive recreational-level Australian Rules football players were assessed on the agility tests and a drop jump test to assess RS. Interday and interrater reliability was also assessed. The agility tests involved performing 10 trials of one-on-one agility tasks against 2 testers (opponents), in which the objective was to be in a position to tackle (defending) or to evade (attacking) the opponent. Both agility tests had good reliability (intraclass correlation > 0.8, %CV < 3, and no significant differences between test occasions [p > 0.05], and interrater reliability was very high [r = 0.997, p < 0.001]). The common variance between the agility tests was 45%, indicating that they represented relatively independent skills. There was a large correlation between RS and defending agility (r = 0.625, p = 0.004), and a very large correlation with attacking agility (r = 0.731, p < 0.001). Defending and attacking agility have different characteristics, possibly related to the footwork, physical, and cognitive demands of each. Nonetheless, RS seems to be important for agility, especially for attacking agility.

  1. 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

  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. Natural evolution of skin-test sensitivity in patients with IgE-mediated hypersensitivity to cephalosporins.

    PubMed

    Romano, A; Gaeta, F; Valluzzi, R L; Zaffiro, A; Caruso, C; Quaratino, D

    2014-06-01

    There are studies demonstrating that skin-test sensitivity to penicillins can decrease over time and that allergic patients may lose sensitivity if the responsible compounds are avoided. With regard to subjects with IgE-mediated hypersensitivity to cephalosporins, however, such studies are lacking. We evaluated prospectively in a 5-year follow-up 72 cephalosporin-allergic patients. After the first evaluation, patients were classified into two groups according to their patterns of allergologic-test positivity: to both penicillins and cephalosporins (group A), or only to cephalosporins (group B). Skin tests and serum-specific IgE assays were repeated 1 year later and, in case of persistent positivity, 3 and 5 years after the first allergologic examination. Seven (43.7%) of the 16 subjects of group A and 38 (67.8%) of the 56 patients of group B became negative; one was lost to follow-up. Patients of group B became negative sooner and more frequently than group A subjects.

  4. 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.

  5. Autologous serum skin test vs autologous plasma skin test in patients with chronic urticaria: evaluation of reproducibility, sensitivity and specificity and relationship with disease activity, quality of life and anti-thyroid antibodies.

    PubMed

    Kocatürk, Emek; Kavala, Mukaddes; Kural, Esra; Sarıgul, Sukran; Zındancı, Ilkin

    2011-01-01

    Recent concerns have arisen about the specificity and interpretation of the autologous serum skin test (ASST), suggesting that ASST might produce false-positive results, and proposing the use of autologous plasma (APST) instead for intradermal testing in autoreactive urticaria. We investigated autoreactivity to autologous plasma and compared the results for reproducibility, sensitivity, specificity and accuracy and evaluated their association with quality of life and anti-TPO antibodies. 70 adults with chronic spontaneous urticaria (CU) and 62 controls underwent testing with ASST and APST and the tests were repeated two days after the first visit. Blood tests measured anti-TPO levels. Disease activity was assessed by urticaria activity score (UAS-7) and quality of life impairment was assessed by DLQI and CU-Q(2)oL. There were no statistically significant differences between ASST (+) and ASST (-) and also APST (+) and APST (-) patients with regard to disease duration, anti-TPO antibodies, urticaria activity scores, DLQI scores and CU-Q(2)oL scores. The results of first ASST and APST were well correlated with the results of second ASST and APST. The specificity of the two tests was similar, while ASST had a higher sensitivity and accuracy. Our results showed that there is no need to use autologous plasma instead of autologous serum for intradermal testing in CU.

  6. Determination of N-acetylglucosamine in cosmetic formulations and skin test samples by hydrophilic interaction liquid chromatography and UV detection.

    PubMed

    Pedrali, Alice; Bleve, Mariella; Capra, Priscilla; Jonsson, Tobias; Massolini, Gabriella; Perugini, Paola; Marrubini, Giorgio

    2015-03-25

    N-Acetylglucosamine is an ingredient in pharmaceuticals, nutritional supplements and in cosmetics. N-Acetylglucosamine in cosmetics is expected to improve skin hydration, reparation, and to contribute as anti-wrinkle agent. This study reports on the validation and application of an HPLC method based on HILIC and UV detection for determining N-acetylglucosamine in cosmetics and in samples obtained after testing the skin exposed to cosmetics formulations. The chromatographic column used is a ZIC(®)-pHILIC (150 mm × 4.6 mm, 5 μm particle size) on which a mobile phase containing acetonitrile-aqueous KH2PO4 (70:30, v/v) 15 mM was applied in isocratic elution mode injecting 20 μl of sample at 0.5 ml/min constant flow-rate and 10±1°C column temperature. Under these conditions the total run time was 10 min and N-acetylglucosamine eluted baseline separated from all other compounds in the samples. Calibration in the range from 40 to 80 μg/ml allowed to assess the method linearity (R(2)>0.999) in a concentration range corresponding to about 50% to 120% of the expected levels of N-acetylglucosamine in the formulations. Precision expressed by RSD% was always better than 2% in intra-day and inter-day assays of authentic samples. Accuracy was in all cases within 95-105% of the expected concentration value in formulations containing N-acetylglucosamine. The sensitivity of the method was at the level of 10 μg/ml as limit of detection, and at 40 μg/ml as limit of quantitation. The application of the method to formulations containing solid lipid nanoparticles documents its usefulness in cosmetic quality control. The results witness that the method is also suitable for the determination of N-acetylglucosamine in samples obtained from skin test strips.

  7. 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.

  8. 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...

  9. Acoustic fatigue testing on different materials and skin-stringer elements

    NASA Astrophysics Data System (ADS)

    Koenig, Klaus

    1994-09-01

    Within a comparative study, 29 different coupons covering 8 different designs and 6 different materials were fatigued by an excitation of 30 g(exp 2)/Hz on a shaker. The selected designs and materials represent realistic alternatives of an aircraft surface structure. The investigation led to the following conclusion: (1) Besides classical aluminium, CFRP is the best material with regard to sonic fatigue. (2) Al/Li, ARALL and Al layer materials showed shorter life times than the classical Al. (3) The most striking improvement in design for the dimensions selected here was achieved with separate doublers between skin and stringer. (4) The modal damping found was most often smaller than the 1.7 percent of the critical as known from ESDU for Al. (5) Pure CFRP without rivets showed the smallest damping: 0.6 - 0.9 percent.

  10. 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

  11. 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.

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

    PubMed

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

    2010-03-01

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

  13. Delayed-type hypersensitivity, contact sensitivity, and phytohemagglutinin skin-test responses of heat- and cold-stressed calves.

    PubMed

    Kelley, K W; Greenfield, R E; Evermann, J F; Parish, S M; Perryman, L E

    1982-05-01

    Three-week-old Holstein bull calves were used to investigate the effect of a 2-week chronic heat (35 C) or cold (-5 C) exposure on delayed-type hypersensitivity (DTH) reactions to purified protein derivative after sensitization with heat-killed Mycobacterium tuberculosis, contact sensitivity (CS) reactions to 1-fluoro-2,4-dinitrobenzene, and phytohemagglutinin (PHA) skin tests. Heat exposure reduced expression of DTH reactions by 42% and CS reactions by 38% at 24 hours after elicitation of the responses. The PHA-induced skin tests were not affected after 1 week of heat exposure, but this reaction was reduced by 20% after 2 weeks of heat exposure. The immune response of calves exposed to cold air temperatures was more complex. Cold exposure suppressed CS reactions by 39% at the end of both the 1st and 2nd weeks. The PHA response was reduced by 39% after 2 weeks of cold exposure. The DTH response depended on duration of cold exposure. The DTH reaction was increased by 42% after 1 week, but was reduced by 14% after 2 weeks. These data are consistent with the hypothesis that environmental stressors alter host resistance by affecting the immune system. Furthermore, these stress-induced changes in immune events depend on the type of immune response, the nature of the environmental stressor, and the length of time that calves are exposed to the stressor.

  14. Impact of C-reactive protein test results on evidence-based decision-making in cases of bacterial infection

    PubMed Central

    2012-01-01

    Background C-reactive protein (CRP) is widely used to detect bacterial infection in children. We investigated the impact of CRP test results on decision-making and summarized the evidence base (EB) of CRP testing. Methods We collected information from the hospital records of 91 neonates with suspected sepsis and of 152 febrile children with suspected infection on the number of ordered CRP tests, the number of EB-CRP tests, and the impact of the test results on decision-making. CRP diagnostic accuracy studies focusing on pediatric infections were reviewed critically. The main outcomes were the proportion of CRP tests that were EB and the proportion of tests that affected decision-making. A secondary outcome was the overall one-year expenditure on CRP testing. Results The current EB for CRP testing in pediatric infections is weak and suggests that CRP is of low diagnostic value. Approximately 54.8% of tests performed for suspected neonatal sepsis and 28% of tests performed for other infections were EB; however, the results of only 12.9% of neonatal sepsis tests and of 29.9% of tests on children with other infections informed decision-making. The one-year overall cost for CRP testing and related health care was $26,715.9. Conclusions The routine ordering of CRP for children with infections is based on weak evidence. The impact of the CRP test results on decision-making is rather small, and CRP ordering may contribute to unnecessary health care expenditures. Better quality research is needed to definitively determine the diagnostic accuracy of CRP levels in children with infections. PMID:22943554

  15. 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.

  16. Cardiovascular reactivity to a marital conflict version of the Trier social stress test in intimate partner violence perpetrators.

    PubMed

    Romero-Martínez, Angel; Nunes-Costa, Rui; Lila, Marisol; González-Bono, Esperanza; Moya-Albiol, Luis

    2014-07-01

    Intimate partner violence (IPV) perpetrators have been categorized into two groups based on their heart rate (HR) reactivity to stress following Gottman's studies. Overall, type I perpetrators tend to show autonomic underarousal, whereas type II or reactive perpetrators present a hyper-reactivity in anticipation of stress. In this study, changes in HR, pre-ejection period (PEP), vagal ratio as well as psychological state variables (anxiety and anger) in response to stress were assessed, comparing a group of type II IPV perpetrators (based on violence reports and psychological assessment; n = 17; mean age = 37) with non-violent controls (n = 17; mean age = 35) using modified version of the Trier Social Stress Test. IPV perpetrators had higher HRs and lower vagal ratios than controls, particularly during the recovery period. Moreover, the former presented shorter PEPs than controls. There were no differences between groups in the magnitude of response of the HR, PEP or vagal ratio. High baseline anxiety and anger were associated with an HR increase during the preparation time in IPV perpetrators but not in controls. These findings indicate a different cardiovascular pattern of response to psychosocial stress in IPV perpetrators, especially during recovery. Thus, they contribute to understanding the biological functioning of violence sub-types, supporting the validity of cardiovascular measures as diagnostic indicators for IPV classification.

  17. 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

  18. Towards AOP application--implementation of an integrated approach to testing and assessment (IATA) into a pipeline tool for skin sensitization.

    PubMed

    Patlewicz, Grace; Kuseva, Chanita; Kesova, Antonia; Popova, Ioanna; Zhechev, Teodor; Pavlov, Todor; Roberts, David W; Mekenyan, Ovanes

    2014-08-01

    Since the OECD published the Adverse Outcome Pathway (AOP) for skin sensitization, many efforts have focused on how to integrate and interpret nonstandard information generated for key events in a manner that can be practically useful for decision making. These types of frameworks are known as Integrated Approaches to Testing and Assessment (IATA). Here we have outlined an IATA for skin sensitization which focuses on existing information including non testing approaches such as QSAR and read-across. The IATA was implemented into a pipeline tool using OASIS technology to provide a means of systematically collating and compiling relevant information which could be used in an assessment of skin sensitization potential. A test set of 100 substances with available skin sensitization information was profiled using the pipeline IATA. In silico and in chemico profiling information alone was able to correctly predict skin sensitization potential, with a preliminary accuracy of 73.85%. Information from other relevant endpoints (e.g., Ames mutagenicity) was found to improve the accuracy (to 87.6%) when coupled with a reaction chemistry mechanistic understanding. This pipeline platform could be useful in the assessment of skin sensitization potential and marks a step change in how non testing approaches can be practically applied.

  19. 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...

  20. Aerobic exercise attenuates blood pressure reactivity to cold pressor test in normotensive, young adult African-American women.

    PubMed

    Bond, V; Mills, R M; Caprarola, M; Vaccaro, P; Adams, R G; Blakely, R; Roltsch, M; Hatfield, B; Davis, G C; Franks, B D; Fairfax, J; Banks, M

    1999-01-01

    Exaggerated blood pressure reactivity to behavioral stress has been observed in the African-American population, and such a pressor response is believed to play a role in hypertension. Regular aerobic exercise has been shown to exert an anti-hypertensive effect, and this may alter the blood pressure hyperreactivity observed in African Americans. To test the hypothesis that aerobic exercise attenuates pressor reactivity in African Americans, we studied eight healthy aerobically-trained normotensive African-American females and five similar sedentary females. The stress stimuli consisted of the cold pressor test with the foot immersed in ice water for two minutes. The aerobic exercise training protocol consisted of six weeks of jogging at 60-70% of peak oxygen uptake (VO2peak), three days/week for 35 min/exercise session. Systolic blood pressure, diastolic blood pressure, mean arterial blood pressure, heart rate, cardiac output, total peripheral resistance, and forearm blood flow were measured. Manifestation of a training effect was illustrated by a 24.1 +/- 0.2% increase in VO2peak (26.9 +/- 1.2 mL x kg(-1) min(-1) vs 35.4 +/- 1.6 mL x kg(-1) min(-1)) (P<.05). Within the exercise-trained group there was a 6.3 +/- .15% decrease in systolic pressure (129 +/- 4.6 mm Hg vs. 121 +/- 5.4 mm Hg) (P<.05), and a 5.0 +/- .05% decrement in mean arterial blood pressure (99 +/- 3.3 mm Hg vs 94 +/- 3.6 mm Hg) (P<.05) during the cold pressor test. Pressor reactivity to cold stress did not change in the untrained group. Measures of heart rate, cardiac output, total peripheral resistance, and forearm blood flow were unaltered during conditions of the cold pressor test. We conclude that aerobic exercise attenuates the blood pressure reactivity to behavioral stress in young, adult normotensive African-American females. A lifestyle change such as exercising may play a role in reducing the risk of hypertension in African-American women.

  1. Quantifying and Addressing the DOE Material Reactivity Requirements with Analysis and Testing of Hydrogen Storage Materials & Systems

    SciTech Connect

    Khalil, Y. F.

    2012-04-30

    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.

  2. 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.

  3. Evaluation of indirect fluorescent antibody test (IFAT) for the diagnosis and screening of lumpy skin disease using Bayesian method.

    PubMed

    Gari, G; Biteau-Coroller, F; LeGoff, C; Caufour, P; Roger, F

    2008-06-22

    The performance of indirect fluorescence antibody test (IFAT) for serological diagnosis and screening of lumpy skin disease (LSD) was evaluated using methods without gold standard. Virus neutralization test (VNT) was used as the second test and the study sites were selected from two different geographical places in Ethiopia to get different disease prevalence. The analysis of conditional dependent Bayesian model for the accuracy of IFAT showed that sensitivity, specificity, prevalence of the population Pi(1) and the population Pi(2) were 0.92 (0.89-0.95), 0.88 (0.85-0.91), 0.28 (0.25-0.32) and 0.06 (0.048-0.075), respectively. The posterior inferences obtained for VNT sensitivity, specificity and conditional correlation between the tests for sensitivity (rhoD) and specificity (rhoDc) were 0.78 (0.74-0.83), 0.97 (0.95-0.99), 0.052 (-0.03-0.15) and 0.019 (-0.01-0.06), respectively. The interval estimation of conditional correlation for both sensitivity and specificity clusters around zero and thus conditional dependence between the two tests was not significant. Although accuracy measure would not be the only basis for test selection, the result of our study demonstrated that IFAT has a reasonable high accuracy to be used for the diagnosis and sero-surveillance analysis of LSD in the target population.

  4. Comparison of intradermal skin testing (IDST) and serum allergen-specific IgE determination in an experimental model of feline asthma.

    PubMed

    Lee-Fowler, Tekla M; Cohn, Leah A; DeClue, Amy E; Spinka, Christine M; Ellebracht, Ryan D; Reinero, Carol R

    2009-11-15

    Intradermal skin testing (IDST) and allergen-specific IgE determination are used to determine allergen sensitization. In cats, studies have found poor correlation between the two tests. However, these studies were mainly conducted in pet cats sensitized to unknown allergens with unknown dose and duration of exposure. We hypothesized that in an experimental model of allergic sensitization where these variables are controlled, IDST would demonstrate greater sensitivity and specificity than would serum allergen-specific IgE determination. A model of feline asthma employing Bermuda grass allergen (BGA) or house dust mite allergen (HDMA) was used to test the hypothesis. Thirteen cats were assigned to undergo sensitization to BGA, HDMA or saline (placebo). Bronchoalveolar lavage fluid confirmed development of an asthmatic phenotype. Serum collection and IDST were performed on D0, D28 and D50. A portion of serum was pooled, and an aliquot heat inactivated (HI) to destroy IgE. Individual, pooled, and pooled HI samples were used for allergen-specific IgE determination using an Fc epsilon R1 alpha-based ELISA; pooled samples were also analyzed using an enzymoimmunometric assay. Sensitivity (SE), specificity (SP), and positive and negative predictive values (PPV and NPV) were calculated for IDST and for BGA- and HDMA-specific IgE. Combined results for IDST found SE=90.9%, SP=86.7%, PPV=83.3%, and NPV=92.9%. For ELISA-based serum IgE testing, the SE=22.7%, SP=100%, PPV=100% and NPV=63.8%. The enzymoimmunometric assay did not detect sensitizing IgE, but did detect IgE reactivity to a variety of irrelevant allergens (even in HI samples). Sensitivity of IDST was greater than sensitivity of serum IgE measurement supporting use as a screening test for aeroallergens. Both IDST and allergen-specific IgE determination via ELISA were specific; either test can be used to guide selection of allergens for immunotherapy. The enzymoimmunometric assay was unreliable and cannot be recommended.

  5. Comparison of the tuberculin skin test and the QuantiFERON-TB Gold test in detecting latent tuberculosis in health care workers in Iran

    PubMed Central

    2016-01-01

    OBJECTIVES: The tuberculin skin test (TST) and the QuantiFERON-TB Gold test (QFT) are used to identify latent tuberculosis infections (LTBIs). The aim of this study was to determine the agreement between these two tests among health care workers in Iran. METHODS: This cross-sectional study included 177 tuberculosis (TB) laboratory staff and 67 non-TB staff. TST indurations of 10 mm or more were considered positive. The Student’s t-test and the chi-square test were used to compare the mean score and proportion of variables between the TB laboratory staff and the non-TB laboratory staff. Kappa statistics were used to evaluate the agreement between these tests, and logistic regression was used to assess the risk factors associated with positive results for each test. RESULTS: The prevalence of LTBIs according to both the QFT and the TST was 17% (95% confidence interval [CI], 12% to 21%) and 16% (95% CI, 11% to 21%), respectively. The agreement between the QFT and the TST was 77.46%, with a kappa of 0.19 (95% CI, 0.04 to 0.34). CONCLUSIONS: Although the prevalence of LTBI based on the QFT and the TST was not significantly different, the kappa statistic was low between these two tests for the detection of LTBIs. PMID:27457062

  6. Specificity of the comparative skin test for bovine tuberculosis in Great Britain

    PubMed Central

    Goodchild, A. V.; Downs, S. H.; Upton, P.; Wood, J. L. N.; de la Rua-Domenech, R.

    2015-01-01

    A novel method for estimating specificity of the Single Intradermal Comparative Cervical Tuberculin (SICCT) test for bovine tuberculosis (bTB) using surveillance tests results is reported. The specificity of the SICCT test at three cut-offs was estimated from the dates, locations and skinfold measurements of all routine tests carried out in Officially TB Free (OTF) cattle herds in Great Britain (GB) between 2002 and 2008, according to their separation (by distance and time) from known infected (OTF-withdrawn) herds. The proportion of animals that tested positive was constant (P>0.20) when the distance between tested herds and nearest infected herd exceeded 8 km. For standard cut-off, calculated specificity was 99.98 per cent (95 per cent confidence interval ±0.004 per cent), equating to one false positive result per 5000 uninfected animals tested. For severe cut-off it was 99.91 per cent (±0.013 per cent) and for ultrasevere cut-off (selecting all reactors and inconclusive reactors) it was 99.87 per cent (±0.017 per cent). The estimated positive predictive value of the test averaged 91 per cent and varied by regional prevalence. This study provides further evidence of the high specificity of the SICCT test under GB conditions, suggests that over 90 per cent of cattle currently culled using this test in GB were infected, and endorses slaughter of at least these cattle for bTB control. PMID:26338518

  7. 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.

  8. Chromium and reactive element modified aluminide diffusion coatings on superalloys: Environmental testing

    SciTech Connect

    Bianco, R.; Rapp, R.A. ); Smialek, J.L. )

    1993-04-01

    The isothermal oxidation of reactive element (RE)-doped aluminide coatings on IN 713LC alloy substrates at 1100 C in air formed a continuous slow-growing [alpha]-Al[sub 2]O[sub 3] scale after 44 h of exposure. RE-free (reactive element-free) aluminide coatings were characterized by a cracked oxide scale which exposed an underlying voided coating surface. The cyclic oxidation behavior of Cr/RE-modified aluminide diffusion coatings on Rene 80 and IN 713LC alloy substrates, and of RE-doped aluminide coatings on IN 713LC alloy substrates, at 1100 C in static air was determined. Coatings deposited by the above pack (AP) arrangement, as opposed to the powder contacting (PC) arrangement, showed improved resistance to cyclic oxidation attack. RE-doped and Cr/RE-modified aluminide coatings exhibited considerably more adherent protective Al[sub 2]O[sub 3] scales compared to undoped aluminide coatings. The hot corrosion behavior of Cr/RE-modified aluminide coatings on Rene 80 and Mar-M247 alloy substrates at 900 C in a 0.1 % sO[sub 2]/O[sub 2] gas mixture also was determined. The Cr/RE-modified aluminide coatings provided better resistance to hot corrosion attack (i.e., thin film studies) than a commercial low activity aluminide coating. Coating lifetimes were strongly dependent on the chromium surface composition, since a mixed (Al, Cr)[sub 2]O[sub 3] scale better resists attack by the molten salt.

  9. Skin Cancer

    MedlinePlus

    ... version of this page please turn Javascript on. Skin Cancer What is Skin Cancer? Skin cancer is the most common type ... of approximately 9,480 Americans in 2013. Can Skin Cancer Be Treated? Most basal cell and squamous ...

  10. 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

  11. Histological assessment of cellular immune response to the phytohemagglutinin skin test in Brazilian free-tailed bats (Tadarida brasiliensis).

    PubMed

    Turmelle, Amy S; Ellison, James A; Mendonça, Mary T; McCracken, Gary F

    2010-11-01

    Bats are known reservoirs for numerous emerging infectious diseases, occupy unique ecological niches, and occur globally except for Antarctica. Given their impact on human and agricultural health, it is critical to understand the mechanisms underlying immunocompetence in this reservoir host. To date, few studies have examined immune function in the Order Chiroptera, particularly among natural colonies of bats. The phytohemagglutinin (PHA) skin test has been widely used to measure delayed-type cellular immune response in a wide variety of vertebrates, and has been routinely employed in immunoecological studies. Although this test is frequently described as a measure of T cell proliferation, recent studies indicate it may represent a combination of immune responses. In mammals, the immune response is differentially, temporally and spatially regulated, therefore, we characterized the infiltrating leukocyte response to the PHA skin test in bats by examining a time-series of histological sections from PHA and saline injection areas in 41 Brazilian free-tailed bats (Tadarida brasiliensis). Results suggest that bats exhibit diverse leukocyte traffic within 6 h, and up to 24 h following subcutaneous PHA injection. There was a significant presence of lymphocytes and neutrophils, as well as eosinophils, basophils, and macrophages observed in the PHA-injected tissues, compared with saline-injected control tissues. We observed a highly significant negative correlation between the number of lymphocytes and neutrophils in PHA-injected tissue, with peak lymphocyte response at 12 h, and peak neutrophil response at 24 h post-injection. These results indicate substantial variation in the immune response of individuals, and may aid our understanding of disease emergence in natural populations of bats.

  12. Synthetic Source Inversion Tests with the Full Complexity of Earthquake Source Processes, Including Both Supershear Rupture and Slip Reactivation

    NASA Astrophysics Data System (ADS)

    Song, Seok Goo; Dalguer, Luis A.

    2017-03-01

    Recent studies in dynamic source modeling and kinematic source inversion show that earthquake rupture may contain greater complexity than we previously anticipated, including multiple slipping at a given point on a fault. Finite source inversion methods suffer from the nonuniqueness of solutions, and it may become more serious if we aim to resolve more complex rupture models. In this study, we perform synthetic inversion tests with dynamically generated complex rupture models, including both supershear rupture and slip reactivation, to understand the possibility of resolving complex rupture processes by inverting seismic waveform data. We adopt a linear source inversion method with multiple windows, allowing for slipping from the nucleation of rupture to the termination at all locations along a fault. We regularize the model space effectively in the Bayesian framework and perform multiple inversion tests by considering the effect of inaccurate Green's functions and station distributions. We also perform a spectral stability analysis. Our results show that it may be possible to resolve both a supershear rupture front and reactivated secondary slipping using the linear inversion method if those complex features are well separated from the main rupture and produce a fair amount of seismic energy. It may be desirable to assume the full complexity of an earthquake rupture when we first develop finite source models after a major event occurs and then assume a simple rupture model for stability if the estimated models do not show a clear pattern of complex rupture processes.

  13. 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.

  14. Screening for tuberculosis infection among newly arrived asylum seekers: Comparison of QuantiFERON®TB Gold with tuberculin skin test

    PubMed Central

    Winje, Brita Askeland; Oftung, Fredrik; Korsvold, Gro Ellen; Mannsåker, Turid; Jeppesen, Anette Skistad; Harstad, Ingunn; Heier, Berit Tafjord; Heldal, Einar

    2008-01-01

    Background QuantiFERON®TB Gold (QFT) is a promising blood test for tuberculosis infection but with few data so far from immigrant screening. The aim of this study was to compare results of QFT and tuberculin skin test (TST) among newly arrived asylum seekers in Norway and to assess the role of QFT in routine diagnostic screening for latent tuberculosis infection. Methods The 1000 asylum seekers (age ≥ 18 years) enrolled in the study were voluntarily recruited from 2813 consecutive asylum seekers arriving at the national reception centre from September 2005 to June 2006. Participation included a QFT test and a questionnaire in addition to the mandatory TST and chest X-ray. Results Among 912 asylum seekers with valid test results, 29% (264) had a positive QFT test whereas 50% (460) tested positive with TST (indurations ≥ 6 mm), indicating a high proportion of latent infection within this group. Among the TST positive participants 50% were QFT negative, whereas 7% of the TST negative participants were QFT positive. There was a significant association between increase in size of TST result and the likelihood of being QFT positive. Agreement between the tests was 71–79% depending on the chosen TST cut-off and it was higher for non-vaccinated individuals. Conclusion By using QFT in routine screening, further follow-up could be avoided in 43% of the asylum seekers who would have been referred if based only on a positive TST (≥ 6 mm). The proportion of individuals referred will be the same whether QFT replaces TST or is used as a supplement to confirm a positive TST, but the number tested will vary greatly. All three screening approaches would identify the same proportion (88–89%) of asylum seekers with a positive QFT and/or a TST ≥ 15 mm, but different groups will be missed. PMID:18479508

  15. Comparison of a qualitative canine C-reactive protein test to a quantitative test and traditional markers of inflammation - Short communication.

    PubMed

    Smuts, Celia M; Mills, Jennifer N; Gaál, Tibor

    2015-09-01

    Qualitative tests for C-reactive protein (CRP) are available for use in dogs, and provide a rapid in-house method of detecting acute inflammation. The aim of this study was to compare results from a qualitative CRP lateral flow test (Teco CRP FASTest) to those obtained from a quantitative CRP ELISA and to traditional methods of detecting inflammation, including total leukocyte and neutrophil numbers, presence of immature neutrophils and a left shift, presence or absence of toxic changes in neutrophils and plasma fibrinogen concentration in whole blood and serum samples collected from 113 client-owned dogs. More dogs had CRP FASTest positive results than had quantitatively increased CRP (ELISA) or increases in traditional methods used for measuring inflammation. Few dogs had increases in markers of inflammation but no elevated CRP. The qualitative CRP FASTest was found to be a sensitive test for detecting increased CRP concentration and was positive more frequently than were traditional markers of inflammation.

  16. 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

  17. ENVIRONMENTAL REACTIVITY OF SOLID-STATE HYDROGEN SYSTEMS: FUNDAMENTAL TESTING AND EVALUATION

    SciTech Connect

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

    2010-12-13

    In order to enable the commercial acceptance of solid state hydrogen storage materials and systems it is important to understand the risks associated with the environmental exposure of various materials. In some instances, these materials are sensitive to the environment surrounding the material and the behavior is unique and independent to each material. The development of testing procedures to evaluate a material's behavior with different environmental exposures is a critical need. In some cases material modifications may be needed in order to reduce the risk of environmental exposure. We have redesigned two standardized UN tests for clarity and exactness; the burn rate and self-heating tests. The results of these and other UN tests are shown for ammonia borane, NH{sub 3}BH{sub 3}, and alane, AlH{sub 3}. The burn rate test showed a strong dependence on the preparation method of aluminum hydride as the particle size and trace amounts of solvent greatly influence the test results. The self-heating test for ammonia borane showed a failed test as low as 70 C in a modified cylindrical form. Finally, gas phase calorimetry was performed and resulted in an exothermic behavior within an air and 30%RH environment.

  18. Dragon Skin - How It Changed Body Armor Testing in the United States Army

    DTIC Science & Technology

    2015-09-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA JOINT APPLIED PROJECT DRAGON SKIN—HOW IT CHANGED BODY ARMOR TESTING IN THE...AND DATES COVERED Joint applied project 4. TITLE AND SUBTITLE DRAGON SKIN—HOW IT CHANGED BODY ARMOR TESTING IN THE UNITED STATES ARMY 5...Std. 239-18 ii THIS PAGE INTENTIONALLY LEFT BLANK iii Approved for public release; distribution is unlimited DRAGON SKIN—HOW IT

  19. A comparison of the efficacy of ketotifen (HC 20-511) with sodium cromoglycate (SCG) in skin test positive asthma.

    PubMed Central

    Clarke, C W; May, C S

    1980-01-01

    1 Ketotifen (HC 20-511 Sandoz) 1 mg twice daily for 12 weeks was found to be equivalent to sodium cromoglycate (SCG) 20 mg four times daily for 12 weeks in 35 skin test positive asthmatic patients in a randomised double-blind cross-over study. 2 No statistically significant difference between the two drugs in mean values for daily peak flow rates, diary card scores and spirometry at monthly visits was demonstrated. 3 Treatment failures as judged by severe asthma requiring withdrawal from the trial or addition of short courses of prednisone occurred in three patients on each drug. 4 Sedation was noted by 10 patients onHC 20-511 and 5 on SCG. 5 Weight loss was noted in those patients on SCG, but not those on HC 20-511. PMID:6108129

  20. 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.

  1. 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.

  2. 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

  3. Markers of endothelial dysfunction and evaluation of vascular reactivity tests in Behçet disease.

    PubMed

    Ozuguz, Pinar; Karabulut, Ayse Anil; Tulmac, Murat; Kisa, Ucler; Kocak, Mukadder; Gunduz, Ozgur

    2014-11-01

    We assessed endothelial dysfunction (ED) in patients with Behcet disease (BD; n=40) and healthy controls (n=20). Serum lipid, homocysteine, asymmetric dimethylarginine (ADMA) and high-sensitivity C-reactive protein (hsCRP) levels, erythrocyte sedimentation rates (ESRs), and ultrasonographic flow-mediated dilatation (FMD) were measured. Mean hsCRP, ESR, homocysteine, and ADMA were significantly higher in the BD group (P<.001 for all). Patients with active BD had higher serum levels of hsCRP, homocysteine, and ESR compared with those in remission (P<.001, P<.001, and P=.005, respectively). Flow-mediated dilatation was significantly lower in patients with BD than in controls (P=.001). Flow-mediated dilatation correlated negatively with BD duration and serum ADMA levels (P<.001, r=-.745 and P<.001, r=-.682); a positive correlation was seen between serum ADMA levels and BD duration (P<.001, r=.552). Only stepwise multivariate regression analysis revealed BD duration to have a significant effect on FMD. Flow-mediated dilatation, in conjunction with markers of inflammation, may evaluate ED in patients with BD.

  4. 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.

  5. Evaluation of the validity of the UN SADT H.4 test for solid organic peroxides and self-reactive substances.

    PubMed

    Steensma, M; Schuurman, P; Malow, M; Krause, U; Wehrstedt, K-D

    2005-01-31

    Many self-accelerating decomposition temperatures (SADTs) of solid organic peroxides and self-reactive substances have been determined with the UN test method H.4, which is a scaled down test in a small Dewar vessel. For solid organic peroxides and solid self-reactive substances Fierz has questioned this procedure in a recent paper. Fierz concluded that the Dewar test results should not be extrapolated to beyond 8l packages, owing to the thermal insulation value of solids. On the other hand, long term experience with the test, with a great variety of solid organic peroxides and self-reactive substances show about equal critical temperatures in the small Dewar vessel and on 50 kg scale. In the present work, we first checked, by numerical simulations, the Dewar scale versus the larger scale, in a way comparable with Fierz' method: both scales are simulated by spheres, consisting of a number of annular layers, for the large scale the usual external heat loss term is used but for the small scale the outside heat transfer is strongly limited. The outcome of these simulations, covering a variety of physical parameters, supports the concerns expressed by Fierz. After this, we performed accurate cooling and heating experiments with solid organic peroxide in the usual Dewar vessel, provided with a large set of thermocouples. The results of these experiments showed that the simulation model for the Dewar vessel has to be changed from a spherical analogue to a short cylinder of solid material with heat exchange mainly via its top (U(top) approximately 3.5 W/(m(2)K), overall heat transfer coefficient) and some heat exchange (U(side) approximately 0.29 W/(m(2)K)) through its cylindrical and bottom part. With this "modified cylinder" model (being neither an infinitely long cylinder nor a slab) of the Dewar vessel, we found that the UN method H.4 enables an accurate prediction of the SADT, with small deviations of 0+/-2.5 degrees C. Further, by performing a truly three

  6. 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.

  7. 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.

  8. 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...

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. Designing validation studies more efficiently according to the modular approach: retrospective analysis of the EPISKIN test for skin corrosion.

    PubMed

    Hoffmann, Sebastian; Hartung, Thomas

    2006-05-01

    It is claimed that the modular approach to validation, which involves seven independent modules, will make the assessment of test validity more flexible and more efficient. In particular, the aspects of between-laboratory variability and predictive capacity are formally separated. Here, the main advantage of the approach is to offer the opportunity for reduced labour, and thus to allow study designs to be more time efficient and cost effective. The impact of this separation was analysed by taking the ECVAM validation study on in vitro methods for skin corrosivity as an example of a successful validation study - two of its methods triggered new OECD test guidelines. Lean study designs, which reduced the number of tests required by up to 60%, were simulated with the original validation data for the EPISKIN model. By using resampling techniques, we were able to demonstrate the effects of the lean designs on three between-laboratory variability measures and on the predictive capacity in terms of sensitivity and specificity, in comparison with the original study. Overall, the study results, especially the levels of confidence, were only slightly affected by the lean designs that were modelled. It is concluded that the separation of the two modules is a promising way to speed-up prospective validation studies and to substantially reduce costs, without compromising study quality.

  14. Use of the double-loop reactivation test to measure sensitization in aged and welded pH 13-8 Mo martensitic stainless steel

    SciTech Connect

    Cieslak, W.R.; Cieslak, M.J.; Hills, C.R.

    1987-01-08

    Electrochemical potentiokinetic reactivation (EPR) testing provides quantitative detection of small degrees of sensitization. We have used double-loop (DL-EPR) testing, a method which has been characterized for use on austenitic stainless steels, to measure sensitization resulting from aging or from welding of PH 13-8 Mo martensitic stainless steel. Aging at either 500/sup 0/C or 620/sup 0/C results in an increase of the reactivation current density. The 500/sup 0/C treatment promotes preferential susceptibility to corrosion along prior austenite grain boundaries, and the 620/sup 0/C treatment promotes preferential susceptibility along martensite interlath boundaries. A narrow band in the heat-affected zone of autogenous weldments also undergoes localized corrosion during the reactivation scan. Increased reactivation current density is likely caused by classic Cr-depletion resulting from carbide precipitation.

  15. 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...

  16. 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.

  17. Anaphylaxis to the 23-valent pneumococcal vaccine: a second explored case by means of immediate-reading skin tests with pneumococcal vaccines.

    PubMed

    Ponvert, C; Scheinmann, P; de Blic, J

    2010-12-06

    Anaphylaxis to pneumococcal vaccines is rare. In the only one child with anaphylaxis to a first injection of the 23-valent pneumococcal vaccine that has been explored, skin tests and specific IgE determination diagnosed immediate-type hypersensitivity to pneumococcal antigens. We report the case of a child who tolerated three injections of the 7-valent pneumococcal vaccine, but experienced anaphylaxis to a fourth injection of the 23-valent vaccine. Immediate responses in skin tests diagnosed immediate-type hypersensitivity to the two vaccines. Immunizations with the 7-valent pneumococcal vaccine may induce IgE-dependent sensitization to pneumococcal antigens, responsible for anaphylaxis to subsequent injections of pneumococcal vaccines.

  18. Multivariate Models for Prediction of Human Skin Sensitization ...

    EPA Pesticide Factsheets

    One of the lnteragency Coordinating Committee on the Validation of Alternative Method's (ICCVAM) top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary to produce skin sensitization suggests that no single alternative method will replace the currently accepted animal tests. ICCVAM is evaluating an integrated approach to testing and assessment based on the adverse outcome pathway for skin sensitization that uses machine learning approaches to predict human skin sensitization hazard. We combined data from three in chemico or in vitro assays - the direct peptide reactivity assay (DPRA), human cell line activation test (h-CLAT) and KeratinoSens TM assay - six physicochemical properties and an in silico read-across prediction of skin sensitization hazard into 12 variable groups. The variable groups were evaluated using two machine learning approaches , logistic regression and support vector machine, to predict human skin sensitization hazard. Models were trained on 72 substances and tested on an external set of 24 substances. The six models (three logistic regression and three support vector machine) with the highest accuracy (92%) used: (1) DPRA, h-CLAT and read-across; (2) DPRA, h-CLAT, read-across and KeratinoSens; or (3) DPRA, h-CLAT, read-across, KeratinoSens and log P. The models performed better at predicting human skin sensitization hazard than the murine

  19. Occupational skin allergies: testing and treatment (the case of occupational allergic contact dermatitis).

    PubMed

    Holness, D Linn

    2014-02-01

    Occupational contact dermatitis, including occupational allergic contact dermatitis, is one of the most common occupational diseases. Making a timely and accurate diagnosis is important to improving the outcome. Taking a work history and patch testing are essential elements in the diagnostic process. Management, based on an accurate diagnosis, must include both medical treatment to address the disease and workplace modifications as appropriate to reduce exposure the causative agents.

  20. 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.

  1. Comparison of a new ESAT-6/CFP-10 peptide-based gamma interferon assay and a tuberculin skin test for tuberculosis screening in a moderate-risk population.

    PubMed

    Porsa, Emaeil; Cheng, Lee; Seale, Michael M; Delclos, George L; Ma, Xin; Reich, Robert; Musser, James M; Graviss, Edward A

    2006-01-01

    Screening for latent tuberculosis infection (LTBI) with Mantoux tuberculin skin test (TST) has many limitations, including false-positive results due to exposure to Mycobacterium other than tuberculosis (TB) and BCG vaccination. A total of 474 adult inmates in a county jail were screened for LTBI using TST and a new ESAT-6/CFP-10 peptide-based whole-blood gamma interferon (IFN-gamma) assay. LTBI prevalence was 9.0 and 5.4% as determined by TST and IFN-gamma assay, respectively. Overall, agreement between test results was 90% (kappa = 0.25). Positive TST results were significantly associated with increased age (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.01 to 1.08), African-American ethnicity (OR, 4.97; 95% CI, 1.58 to 15.68), foreign birth (OR, 20.20; 95% CI, 4.21 to 97.02) and prior incarceration (OR, 6.19; 95% CI, 1.48 to 25.95). Positive IFN-gamma assay results were significantly associated with African-American ethnicity (OR, 5.58; 95% CI, 1.16 to 26.74). Factors associated with statistically significant discordance between TST and IFN-gamma assay results were African-American ethnicity (OR, 0.29; 95% CI, 0.11 to 0.77), foreign birth (OR, 0.23; 95% CI, 0.07-0.80), and prior incarceration (OR, 0.06; 95% CI, 0.01-0.50). Among subjects born in the United States, African-American ethnicity was the only variable significantly associated with positive test results for both TST (OR, 4.26; 95% CI, 1.38 to 13.16) and IFN-gamma assay (OR, 5.74; 95% CI, 1.19 to 27.75) and remained associated with statistically significant discordance between TST and IFN-gamma assay results. The reactivity of the new IFN-gamma assay is unaffected by prior BCG vaccination or serial TSTs but may be diminished in African-Americans. Future longitudinal studies are needed to assess the sensitivity and specificity of this new assay in detecting LTBI.

  2. 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...

  3. 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…

  4. 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

  5. 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.

  6. 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.

  7. A reactive transport model of CO2-water-rock interaction in a push-pull test in basaltic rocks

    NASA Astrophysics Data System (ADS)

    Hidalgo, J. J.; de Dieuleveult, C.; Agrinier, P.; Lagneau, V.

    2010-12-01

    Basaltic rock formations have been proposed as suitable hosts for CO2 storage. Basalts have a high content in silicate minerals, Ca and Mg, which neutralize the acidic CO2 injected solution. Moreover, under such conditions the formation of stable carbonate minerals, which is the safest way to store CO2, is favored. A series of CO2 injection tests were carried out at the Lamont-Doherty Earth Observatory site (Palisades, New York, USA) in 2005 to assess the basalt neutralization capacity [1, 3]. The tests were conducted in the contact zone between the Palisades sill and the underlying Newark Basin sediments. The Palisades sill consists of dolerite rich in plagioclase and pyroxene [2]. The contact zone between the dolerite and the underlying sediments is characterized by chilled dolerite and contact-metamorphosed sedimentary rocks. The essays consisted of single-well push-pull tests in which an CO2-rich solution was injected in the aquifer and pumped after an incubation period. NaCl was added as a inert tracer. In this work, we focus on one of those push-pull tests. HYTEC code [4] was used to make a reactive transport model. Hydraulic and transport parameters were adjusted by fitting the chloride breakthrough curve. The model shows that the chloride arrival is mainly controlled by the product of the porosity times the longitudinal dispersion. Chemistry results show that the composition of the system (total dissolved inorganic carbon, Ca, Na, and Mg) is governed by the dissolution rate of the minerals. In addition, ion exchange is suggested by Na data. As a future work, modeling of isotopic data to better quantify the dissolution rates is considered. References [1] Assayag, N., J. Matter, M. Ader, D. Goldberg, and P. Agrinier (2009),Water-rock interactions during a CO2 injection field-test: Implications on host rock dissolution and alteration effects, Chemical Geology,265(1-2), 227--235. [2] Goldberg, D., and K. Burgdorff (2005), Natural fracturing and petrophysical

  8. Platelet reactivity in thromboelastometry. Revision of the FIBTEM test: a basic study.

    PubMed

    Biolik, Grzegorz; Kokot, Michał; Sznapka, Mariola; Święszek, Agnieszka; Ziaja, Damian; Pawlicki, Krzysztof; Ziaja, Krzysztof

    2017-05-01

    This study aimed to investigate modifications to the FIBTEM test to better assess fibrinogen levels and the quality of fibrin polymerization in citrated blood using Multiplate impedance aggregometry to verify platelet inhibition. Blood samples from 26 healthy volunteers were subjected to thromboelastometry studies (EXTEM/FIBTEM tests) in accordance with the standard study protocol (cytochalasin D) and according to a modified protocol (synthetic IIbIIIa receptor antagonist vs. acetylsalicylic acid [ASA] + synthetic IIbIIIa receptor antagonist instead of cytochalasin D). Independent of thromboelastometry, Multiplate impedance aggregometry was used to assess the degree of restriction by the platelet blocked with the following treatments: (1) cytochalasin D, (2) synthetic IIbIIIa antagonist or (3) ASA + synthetic IIbIIIa antagonist to assess the aggregation response to activation with an agonist (ADP, collagen, thrombin receptor activating peptide-6 [TRAP-6], and arachidonic acid). Via aggregometry, cytochalasin D more weakly inhibited platelet aggregation than simultaneous administration of the -IIbIIIa receptor antagonist with ASA. However, total platelet aggregation inhibition was observed after simultaneous administration of cytochalasin D combined with a synthetic IIbIIIa receptor antagonist. In the thromboelastometry, a significant decrease of the A10, A20 and MCF parameters were observed in the EXTEM/FIBTEM tests after they were modified by the addition of a synthetic IIbIIIa receptor antagonist alone or in combination with ASA. In conclusion, in this Multiplate- and ROTEM-based laboratory approach, a two-way blockade (IIbIIIa-antagonist + cytochalasine D) was sufficient to completely inhibit procoagulant platelet function as observed by aggregometry and thromboelastometry.

  9. Tuberculin skin test and interferon-gamma release assay use among privately insured persons in the United States.

    PubMed

    Owusu-Edusei, K; Stockbridge, E L; Winston, C A; Kolasa, M; Miramontes, R

    2017-03-28

    OBJECTIVE:

    To describe tuberculin skin test (TST) and interferon-gamma release assay (IGRA) (i.e., QuantiFERON(®)-TB [QFT] and T-SPOT(®).TB [T-SPOT]) use among privately insured persons in the United States over a 15-year period.

    METHODS:

    We used current procedural terminology (CPT) codes for the TST and IGRAs to extract out-patient claims (2000–2014) and determined usage (claims/100 000). The χ(2) test for trend in proportions was used to describe usage trends for select periods.

    RESULTS:

    The TST was the dominant (>80%) test in each year. Publication of guidelines preceded the assignment of QFT and T-SPOT CPT codes by 1 year (2006 for QFT; 2011 for T-SPOT). QFT usage was higher (P < 0.01) than T-SPOT in each year. The average annual increase in the use of QFT was higher than that of T-SPOT (35 vs. 3.8/100 000), and more so when the analytic period was 2011–2014 (65 vs. 38/100 000). However, during that 4-year period (2011–2014), TST use trended downward, with an average annual decrease of 28/100 000. The annual proportion of enrollees tested ranged from 1.1% to 1.5%.

    CONCLUSIONS:

    These results suggest a gradual shift from the use of the TST to the newer IGRAs. Future studies can assess the extent, if any, to which the shift from the use of the TST to IGRAs evolved over time.

  10. 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

  11. 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

    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.

  12. 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.

  13. Predicting susceptibility of alloy 600 to intergranular stress corrosion cracking using a modified electrochemical potentiokinetic reactivation test

    SciTech Connect

    Ahn, M.K.; Kwon, H.S.; Lee, J.H.

    1995-06-01

    Modified double-loop electrochemical potentiokinetic reactivation (DL-EPR) tests were applied to evaluate the degree of sensitization (DOS) for alloy 600 aged at 700 C. Results of the modified DL-EPR test were compared to intergranular stress corrosion cracking (IGSCC) susceptibilities determined in deaerated 0.01 M sodium tetrathionate under deformation at a constant strain rate of 0.93 {times} 10{sup {minus}6}/s. By analyzing the effects of solution concentration, temperature, and scan rate on the electrochemical response in the EPR tests and the morphologies, the optimal modified DL-EPR test condition for alloy 600 was obtained in 0.01 M sulfuric acid + 10 ppm potassium thiocyanate at 25 C and at a scan rate of 0.5 mV/s. The standard DL-EPR test, performed under conditions of 0.5 M H{sub 2}SO{sub 4} + 0.01 M KCNS at 30 C and a scan rate of 1.67 mV/s, provided very poor discriminating power for various DOS of alloy 600 because general and pitting corrosion occurred, in addition to intergranular corrosion. The modified test, however, was highly discriminating because of its highly selective corrosion attack at grain boundaries. IGSCC occurred in samples of alloy 600 aged for < 20 h, and susceptibility to IGSCC{sub s} increased with decreasing aging times up to 1 h, showing maximum IGSCC{sub s} in the sample aged for 1 h. IGSCC{sub s} for the alloy was found to be associated closely with the chromium-depleted profile across grain boundaries. The deeper and narrower chromium-depleted zone produced greater IGSCC{sub s}. It was demonstrated that DOS measured by the modified DL-EPR test was correlated more closely with IGSCC{sub s} than was DOS measured by the standard EPR test. This correlation resulted from the fact that the modified EPR test selectively attacked the more deeply chromium-depleted regions in comparison to the standard EPR test.

  14. 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, ...

  15. Aging Skin

    MedlinePlus

    ... email address Submit Home > Healthy Aging > Wellness Healthy Aging Aging skin More information on aging skin When it ... treated early. Return to top More information on Aging skin Read more from womenshealth.gov Varicose Veins ...

  16. 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

  17. 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

  18. Autologous serum skin test response in chronic spontaneous urticaria and respiratory diseases and its relationship with serum interleukin-18 level.

    PubMed

    Kurt, Emel; Aktas, Ayse; Aksu, Kurtulus; Keren, Metin; Dokumacioglu, Ali; Goss, Christopher H; Alatas, Ozkan

    2011-11-01

    Autologous serum skin test (ASST) is mostly used in chronic spontaneous urticaria (CSU) to show autoreactivity. Interleukin-18 (IL-18) has also been shown to be involved in autoimmune conditions. To investigate the role of autoreactivity assessed by ASST in CSU and respiratory diseases and to investigate whether this autoreactive state is related to IL-18 level or other clinical covariates. Fifty-five patients with CSU (mean age: 40.3 ± 12.3 years), 70 patients with persistent asthma (mean age: 43.7 ± 9.6 years), 21 patients with seasonal allergic rhinitis (SAR) (mean age: 35.5 ± 11.8 years) and 20 normal controls (mean age: 37.7 ± 9.8) were included. All subjects underwent a laboratory examination and skin prick test. ASST was performed and serum IL-18 levels were measured in all subjects. Positive response to ASST and serum IL-18 levels were higher in CSU patients than those with respiratory diseases (asthma and SAR) (P = 0.034 and 0.002, respectively) and normal controls (P = 0.004 and 0.031, respectively). Considering all patients, IL-18 levels were higher in patients with positive ASST (301.8 ± 194.4 vs. 241.8 ± 206.3 pg/ml, P = 0.036) than ASST negative patients. ASST response was associated with disease severity in CSU (P = 0.037) and asthma patients (P = 0.001). Multivariate analysis showed that positive response to ASST was significantly associated with diagnosis of CSU (OR: 3.13, 95% CI: 1.25-7.87) and female gender (OR: 3.98, 95% CI: 1.19-13.38). ASST response could be related with activity of the disease. A positive ASST response found in respiratory diseases patients suggests that it may occur as a result of some inflammatory events during the diseases' process.

  19. Specificity of the Tuberculin Skin Test Is Modified by Use of a Protein Cocktail Containing ESAT-6 and CFP-10 in Cattle Naturally Infected with Mycobacterium bovis

    PubMed Central

    Flores-Villalva, S.; Suárez-Güemes, F.; Espitia, C.; Whelan, A. O.; Vordermeier, M.

    2012-01-01

    The mycobacterial immunodominant ESAT-6 and CFP-10 antigens are strongly recognizable in tuberculosis-infected cattle, and they do not elicit a response in cattle without infection. In addition, they are absent in most environmental mycobacterial species, and therefore, their use can be an alternative to purified protein derivative (PPD) tuberculin in the development of a more specific skin diagnostic test in cattle. The aim of the current study was to assess the potential of an ESAT-6 and CFP-10 (E6-C10) protein cocktail in a skin test format in naturally tuberculosis-infected and paratuberculosis-infected cattle. We also included MPB83 as a third component in one of the protein cocktail preparations. The protein cocktail was tested at different dose concentrations (5, 10, and 15 μg per protein). The best skin response to the E6-C10 protein cocktail was obtained with 10 μg. Subsequently, this concentration was tested in 2 herds with high and low bovine tuberculosis prevalence, the latter with paratuberculosis coinfection. Our data show that the E6-C10 cocktail allows identification of an important proportion of animals that PPDB is not able to recognize, especially in low-prevalence herds. The protein cocktail did not induce reactions in tuberculosis-free cattle or in paratuberculosis-infected cattle. Addition of MPB83 to the protein cocktail did not make any difference in the skin reaction. PMID:22419675

  20. 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…

  1. [Development of a computer-assisted thermoelectric Peltier cold test procedure with integrated photoplethysmography unit for noninvasive evaluation of acral skin circulation].

    PubMed

    Klyscz, T; Hahn, M; Beck, W; Blazek, V; Rassner, G; Jünger, M

    1997-09-01

    Local cold provocation tests are an important, non-invasive diagnostic tool for collecting information about skin perfusion during exposure to cold. In patients suffering from vasospastic circulatory disorders such as Raynaud's phenomenon, it is of particular importance to be able to collect data about acral circulation during the cooling test in the asymptomatic intervals between naturally occurring attacks. By carrying out a series of cold provocation tests, for example, patient response to a newly initiated therapy can be assessed. Here we present a recently developed, computer-aided thermoelectric Peltier device with an integrated finger holder for carrying out local cold provocation tests. The electronic control unit of the Peltier element make it possible to cool or heat to predefined temperatures. At the same time, the temperature of both the finger holder and the skin can be measured. A photoplethysmographic sensor is also integrated within the device, enabling the response of the pulse waves to the controlled temperature changes to be monitored accurately. It is also possible to measure simultaneously laser Doppler flux and capillary pressure in the nailfold and to perform nailfold capillaroscopy to determine red blood cell velocity. The new device provides us with the technical means to study the interrelationship between acral skin perfusion and the thermal regulation of the skin.

  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. Comparison of tuberculin skin testing and T-SPOT.TB for diagnosis of latent and active tuberculosis.

    PubMed

    Simsek, Hulya; Alpar, Sibel; Ucar, Nazire; Aksu, Funda; Ceyhan, Ismail; Gözalan, Aysegul; Cesur, Salih; Ertek, Mustafa

    2010-03-01

    The T-SPOT.TB test does not cross-react with Bacille Calmette-Guérin or most non-tuberculosis mycobacterium species, and is based on IFN-gamma responses to Mycobacterium tuberculosis-specific antigens. The objective of this study was to compare tuberculin skin test (TST) with T-SPOT.TB results used in the diagnosis of active tuberculosis (TB) as well as latent tuberculosis infection (LTBI). A total of 136 subjects participated in three different groups (47 patients with active pulmonary TB, 47 healthy persons without M. tuberculosis exposure, and 42 hospital members with a history of close contact with active TB patients). The T-SPOT.TB sensitivity (83.0%) and the negative predictive value (NPV) (82.6%) in the diagnosis of active TB were significantly higher than those of TST. The sensitivity and NPV of the TST were 38.3 and 60.8%, respectively. The T-SPOT.TB specificity (80.9%) and positive predictive value (81.3%) were lower than those of TST (95.7 and 90.0%, respectively). The performance of T-SPOT.TB and TST for diagnosing LTBI was the same (54.8%). T-SPOT.TB was superior in terms of sensitivity (83.0%); TST detected only 18, whereas T-SPOT.TB test detected 39 out of 47 patients with active TB. T-SPOT.TB is thought to have better performance than TST due to false-negative results in diagnosing active TB. However, it is considered that large prospective longitudinal studies are needed for diagnosing LTBI.

  4. Extent and effects of recurrent shortages of purified-protein derivative tuberculin skin test antigen solutions - United States, 2013.

    PubMed

    2013-12-13

    Two purified-protein derivative (PPD) tuberculin skin test (TST) antigen solutions are approved by the U.S. Food and Drug Administration (FDA): Tubersol (Sanofi Pasteur Limited) and Aplisol (JHP Pharmaceuticals, LLC). Tubersol was out of production in late 2012 through April 2013. Shortages of Aplisol have resulted from increased demand as practitioners have sought a substitute for Tubersol. Tubersol production resumed in May 2013, and supplies had been nearly restored by early June. However, in mid-July, state tuberculosis (TB) control officials notified CDC of difficulty obtaining Tubersol and Aplisol. Sanofi Pasteur notified FDA of a temporary delay in the availability of tuberculin in the 10-dose and 50-dose presentations. In mid-October, the 10-dose presentation was being returned to market, on allocation, which means that historical purchasing practices determine the amount that customers are allotted. In late October, the 50-dose presentation was being returned to market, also on allocation, one vial per historical customer per month. Supplies are forecast to approach normal during January 2014, after distributors have restored their supply chains. A compensatory surge in testing after deferment of testing during the periods of shortage might cause further temporary instability of supplies. In mid-August 2013, officials in 29 of 52 U.S. jurisdictions noted a shortage of at least one PPD TST antigen solution in health departments to the extent that it interrupted activities. This report includes a summary of the extent and effects of the shortages and a reiteration of advice on how to adapt to them.

  5. Skin abscess

    MedlinePlus

    Abscess - skin; Cutaneous abscess; Subcutaneous abscess; MRSA - abscess; Staph infection - abscess ... Skin abscesses are common and affect people of all ages. They occur when an infection causes pus ...

  6. Evaluation of tuberculin skin testing in tuberculosis contacts in Victoria, Australia, 2005-2013.

    PubMed

    Moyo, N; Tay, E L; Denholm, J T

    2015-09-21

    Objectif : Revoir l'utilisation par les programmes du test cutané à la tuberculine (TST) après exposition à la tuberculose (TB) dans l'état de Victoria, en Australie.Méthode : Une revue rétrospective des données recueillies pour la surveillance en matière de santé publique a été réalisée afin d'identifier les caractéristiques démographiques des contacts, notamment le statut en matière du vaccin bacille Calmette-Guérin et l'âge et le résultat du TST.Résultats : La recherche des contacts a été réalisée auprès de 15 094 personnes dont 13 427 (89.0%) ont eu un TST. Le TST a été positif chez 31,4% (95%IC 30,6–32,2) de tous les contacts et chez 48,8% des contacts nés hors d'Australie. Parmi les contacts qui ont été TST négatifs au départ, le taux de conversion après exposition a été de 14,8%. La conversion a été plus fréquente chez les personnes âgées de 45–54 ans, avec <12% de positivité à la fois dans les tranches d'âge les plus jeunes (<5 ans) et les plus âgées (⩾65 ans). Une TB active s'est développée chez 1,1% de tous les contacts. Cependant, les contacts âgés de <5 ans ont eu le risque le plus élevé de développer une TB active après exposition (3,8%), tandis que le risque a été le plus faible chez les personnes âgées de ⩾65 ans (0,3%).Conclusion : Dans l'ensemble, la recherche de contacts et le TST réalisés dans ce contexte semblent aboutir à une proportion élevée de personnes à risque de développer une TB active. Le rendement du dépistage dans certains groupes, en particulier ceux âgés de ⩾65 ans, a été faible, et il faudrait envisager des stratégies alternatives d'investigation.

  7. School based screening for tuberculosis infection in Norway: comparison of positive tuberculin skin test with interferon-gamma release assay

    PubMed Central

    Winje, Brita Askeland; Oftung, Fredrik; Korsvold, Gro Ellen; Mannsåker, Turid; Ly, Ingvild Nesthus; Harstad, Ingunn; Dyrhol-Riise, Anne Margarita; Heldal, Einar

    2008-01-01

    Background In Norway, screening for tuberculosis infection by tuberculin skin test (TST) has been offered for several decades to all children in 9th grade of school, prior to BCG-vaccination. The incidence of tuberculosis in Norway is low and infection with M. tuberculosis is considered rare. QuantiFERON®TB Gold (QFT) is a new and specific blood test for tuberculosis infection. So far, there have been few reports of QFT used in screening of predominantly unexposed, healthy, TST-positive children, including first and second generation immigrants. In order to evaluate the current TST screening and BCG-vaccination programme we aimed to (1) measure the prevalence of QFT positivity among TST positive children identified in the school based screening, and (2) measure the association between demographic and clinical risk factors for tuberculosis infection and QFT positivity. Methods This cross-sectional multi-centre study was conducted during the school year 2005–6 and the TST positive children were recruited from seven public hospitals covering rural and urban areas in Norway. Participation included a QFT test and a questionnaire regarding demographic and clinical risk factors for latent infection. All positive QFT results were confirmed by re-analysis of the same plasma sample. If the confirmatory test was negative the result was reported as non-conclusive and the participant was offered a new test. Results Among 511 TST positive children only 9% (44) had a confirmed positive QFT result. QFT positivity was associated with larger TST induration, origin outside Western countries and known exposure to tuberculosis. Most children (79%) had TST reactions in the range of 6–14 mm; 5% of these were QFT positive. Discrepant results between the tests were common even for TST reactions above 15 mm, as only 22 % had a positive QFT. Conclusion The results support the assumption that factors other than tuberculosis infection are widely contributing to positive TST results in

  8. Sensitive skin: an overview.

    PubMed

    Inamadar, Arun C; Palit, Aparna

    2013-01-01

    Sensitive skin is less tolerant to frequent and prolonged use of cosmetics and toiletries. It is self-diagnosed and typically unaccompanied by any obvious physical signs of irritation. With the change in lifestyle and also with increased opportunity to use many new brands of cosmetics and toiletries, there has been an increase in females complaining of unique sensation in their facial skin. Sensitive skin presents as smarting, burning, stinging, itching, and/or tight sensation in their facial skin. The condition is found in more than 50% of women and 40% of men, creating a sizable demand for products designed to minimize skin sensitivity. Good numbers of invasive and non-invasive tests are designed to evaluate and predict the sensitive skin. Management includes guidelines for selecting suitable cosmetics and toiletries in sensitive skin individuals.

  9. 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

  10. Reactivity measurement in estimation of benzoquinone and benzoquinone derivatives’ allergenicity

    PubMed Central

    Mbiya, Wilbes; Chipinda, Itai; Simoyi, Reuben H.; Siegel, Paul D.

    2015-01-01

    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

  11. 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.

  12. Column test-based optimization of the permeable reactive barrier (PRB) technique for remediating groundwater contaminated by landfill leachates.

    PubMed

    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 0.7-1.0mm 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.

  13. 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.

  14. The Potential Role of Sensory Testing, Skin Biopsy, and Functional Brain Imaging as Biomarkers in Chronic Pain Clinical Trials: IMMPACT Considerations.

    PubMed

    Smith, Shannon M; Dworkin, Robert H; Turk, Dennis C; Baron, Ralf; Polydefkis, Michael; Tracey, Irene; Borsook, David; Edwards, Robert R; Harris, Richard E; Wager, Tor D; Arendt-Nielsen, Lars; Burke, Laurie B; Carr, Daniel B; Chappell, Amy; Farrar, John T; Freeman, Roy; Gilron, Ian; Goli, Veeraindar; Haeussler, Juergen; Jensen, Troels; Katz, Nathaniel P; Kent, Jeffrey; Kopecky, Ernest A; Lee, David A; Maixner, William; Markman, John D; McArthur, Justin C; McDermott, Michael P; Parvathenani, Lav; Raja, Srinivasa N; Rappaport, Bob A; Rice, Andrew S C; Rowbotham, Michael C; Tobias, Jeffrey K; Wasan, Ajay D; Witter, James

    2017-02-27

    Valid and reliable biomarkers can play an important role in clinical trials as indicators of biological or pathogenic processes or as a signal of treatment response. Currently, there are no biomarkers for pain qualified by the U.S. Food and Drug Administration or the European Medicines Agency for use in clinical trials. This article summarizes an Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials meeting in which 3 potential biomarkers were discussed for use in the development of analgesic treatments: 1) sensory testing, 2) skin punch biopsy, and 3) brain imaging. The empirical evidence supporting the use of these tests is described within the context of the 4 categories of biomarkers: 1) diagnostic, 2) prognostic, 3) predictive, and 4) pharmacodynamic. Although sensory testing, skin punch biopsy, and brain imaging are promising tools for pain in clinical trials, additional evidence is needed to further support and standardize these tests for use as biomarkers in pain clinical trials.

  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. Is there interference in the interpretation of the tuberculin skin test in children with intestinal parasitic infestation?

    PubMed Central

    Piñeiro-Pérez, Roi; García-Hortelano, Milagros; José Mellado, María; García-Ascaso, Marta; Medina-Claros, Antonio; Fernández, Nuria; Subirats, Mercedes; José Cilleruelo, María

    2012-01-01

    Background Infestation by intestinal parasites could be a cause of a false-negative tuberculin skin test (TST) result. Objective To evaluate TST results in a population of immigrants and internationally adopted children and to analyze whether intestinal parasitic infestation may modify or not TST results. Methods A cross-sectional observational study which includes adopted children or immigrants evaluated in our hospital between January 2003 and December 2008. The TST was considered as the dependent variable and independent variables were gender, age, geographical origin, bacille Calmette–Guérin scar, nutritional status, immune status, and intestinal parasitism. Results One thousand and seventy-four children were included, of whom 69.6% were female. There was a bacillus Calmette–Guérin scar in 79% of the children and in 20.3% intestinal parasites were found. There were no differences in TST results among infested and non-infested children. Conclusions Intestinal parasitic infestation did not change TST results in our study and these results coincide with recent articles regarding questionable interference that intestinal parasitic infestations may produce on TST results. PMID:23265375

  17. Standard skin prick testing and sensitization to inhalant allergens across Europe--a survey from the GALEN network.

    PubMed

    Heinzerling, L; Frew, A J; Bindslev-Jensen, C; Bonini, S; Bousquet, J; Bresciani, M; Carlsen, K-H; van Cauwenberge, P; Darsow, U; Fokkens, W J; Haahtela, T; van Hoecke, H; Jessberger, B; Kowalski, M L; Kopp, T; Lahoz, C N; Lodrup Carlsen, K C; Papadopoulos, N G; Ring, J; Schmid-Grendelmeier, P; Vignola, A M; Wöhrl, S; Zuberbier, T

    2005-10-01

    Skin prick testing (SPT) is the standard method for diagnosing allergic sensitization but is to some extent performed differently in clinical centres across Europe. There would be advantages in harmonizing the standard panels of allergens used in different European countries, both for clinical purposes and for research, especially with increasing mobility within Europe and current trends in botany and agriculture. As well as improving diagnostic accuracy, this would allow better comparison of research findings in European allergy centres. We have compared the different SPT procedures operating in 29 allergy centres within the Global Allergy and Asthma European Network (GA(2)LEN). Standard SPT is performed similarly in all centres, e.g. using commercial extracts, evaluation after 15-20 min exposure with positive results defined as a wheal >3 mm diameter. The perennial allergens included in the standard SPT panel of inhalant allergens are largely similar (e.g. cat: pricked in all centres; dog: 26 of 29 centres and Dermatophagoides pteronyssinus: 28 of 29 centres) but the choice of pollen allergens vary considerably, reflecting different exposure and sensitization rates for regional inhalant allergens. This overview may serve as reference for the practising doctor and suggests a GA(2)LEN Pan-European core SPT panel.

  18. Colonization with nontuberculous mycobacteria is associated with positive tuberculin skin test reactions in the common marmoset (Callithrix jacchus).

    PubMed

    Wachtman, Lynn M; Miller, Andrew D; Xia, DongLing; Curran, Elizabeth H; Mansfield, Keith G

    2011-06-01

    Mycobacterium tuberculosis infections can result in significant morbidity and mortality in nonhuman primate colonies. Preventative health programs designed to detect infection routinely include tuberculin skin testing (TST). Because Mammalian Old Tuberculin used for TST contains antigens common to a variety of mycobacterial species, false-positive results can occur in animals sensitized to nontuberculous mycobacteria (NTM). Over 11 mo, a large colony of common marmosets (Callithrix jacchus) demonstrated a 3.6% prevalence of equivocal or positive TST reactions (termed 'suspect reactions'). Culture of gastric aspirates, bronchoalveolar lavage fluid, and feces revealed a single animal with a positive fecal culture for Mycobacterium gordonae. PCR amplification of M. gordonae DNA in feces collected from animals with suspect TST reactions (demonstrating a 66.7% colonization rate) and colony controls (demonstrating a 14.3% colonization rate) revealed a significant association between suspect TST reactions and intestinal colonization. Gross and histopathologic evaluation revealed a multifocal lymphadenopathy and granulomatous lymphadenitis in 2 of 4 TST-positive marmosets examined. Counter to expectations, granulomatous lymphoid tissue was culture-positive for M. kansasii rather than M. gordonae. Detection of M. gordonae in the feces of TST-suspect animals likely represents an apathogenic intestinal colonization that may serve as an indicator of NTM exposure, whereas evidence of histopathologic disease is associated with the more pathogenic M. kansasii. Although a high index of suspicion for M. tuberculosis should always be maintained, colonization with NTM organisms represents a cause of suspect TST reactions in common marmosets.

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. ESTIMATES OF RADIATION DOSES TO THE SKIN FOR PEOPLE CAMPED AT WALLATINNA DURING THE UK TOTEM 1 ATOMIC WEAPONS TEST.

    PubMed

    Williams, G A; O'Brien, R S; Grzechnik, M; Wise, K N

    2016-11-23

    A group of Aboriginal people was camped at Wallatinna in South Australia, ~170 km downwind from Emu Field, where an atomic test (the Totem 1 test) was carried out at 07.00 on 15 October 1953 local time (21.30 on 14 October 1953 GMT (Greenwich Mean Time)). They left the camp ~24 hours later. These people stated that a phenomenon that has become known as a 'black mist' rolled through their camp site ~5 hours after detonation and that some of them subsequently became sick, displaying skin reddening and nausea. They feared that the sickness was a result of exposure to high levels of radiation. The purpose of this paper is to determine if these people could have received ionising radiation doses high enough to cause the symptoms displayed. The methodology used for the dose estimates is described in the paper. The exposure modes considered were external exposure due to the passage of a contaminated plume over the camp site, inhalation of material from this plume, external exposure from material deposited on the ground as the plume passed, and consumption of contaminated food and water. The contaminants considered in the airborne cloud and the ground plume were fission products and unburnt plutonium from the nuclear detonation, and neutron activation products caused by vaporisation of the tower used to position the weapon. The source was approximated by a line source. An upper estimate of the effective doses received is ~4 mSv, which is well below the level at which acute radiation effects are observed. This estimate is consistent with earlier assessments, which did not consider inhalation of the contribution from neutron activation products.

  4. Lepromin skin test

    MedlinePlus

    ... Kang G, Lalloo D, White NJ, eds. Manson's Tropical Diseases . 23rd ed. Philadelphia, PA: Elsevier; 2014:chap 41. Read More Chronic Leprosy Review Date 9/10/2015 Updated by: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of ...

  5. Tuberculin Skin Testing

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Tuberculosis (TB) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Tuberculosis Basic TB Facts How TB Spreads Latent TB ...

  6. 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.

  7. Absence of cross-reactivity to carbapenems in patients with delayed hypersensitivity to penicillins.

    PubMed

    Romano, A; Gaeta, F; Valluzzi, R L; Alonzi, C; Maggioletti, M; Zaffiro, A; Caruso, C; Quaratino, D

    2013-12-01

    Studies performed on subjects with IgE-mediated hypersensitivity to penicillins have demonstrated a 1% rate of cross-reactivity between penicillins and both imipenem and meropenem, while a single study found a 5.5% rate of cross-reactivity with imipenem/cilastatin in subjects with T-cell-mediated hypersensitivity to β-lactams, mostly penicillins. We studied 204 consecutive subjects with a well-demonstrated T-cell-mediated hypersensitivity to assess the cross-reactivity with carbapenems and the tolerability of such alternative β-lactams. All 204 subjects underwent skin tests with imipenem/cilastatin and meropenem; 130 of them were skin-tested also with ertapenem. Subjects with negative test results were challenged with these carbapenems. All subjects displayed negative skin tests to carbapenems and tolerated challenges. These data demonstrate the absence of clinically significant T-cell-mediated cross-reactivity between penicillins and carbapenems. Negative delayed-reading skin testing with carbapenems in individuals with documented T-cell-mediated hypersensitivity to penicillins correlates well with subsequent clinical tolerance of therapeutic doses of carbapenems.

  8. 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.

  9. Gremlin inhibits UV-induced skin cell damages via activating VEGFR2-Nrf2 signaling.

    PubMed

    Ji, Chao; Huang, Jin-Wen; Xu, Qiu-Yun; Zhang, Jing; Lin, Meng-Ting; Tu, Ying; He, Li; Bi, Zhi-Gang; Cheng, Bo

    2016-12-20

    Ultra Violet (UV) radiation induces reactive oxygen species (ROS) production, DNA oxidation and single strand breaks (SSBs), which will eventually lead to skin cell damages or even skin cancer. Here, we tested the potential activity of gremlin, a novel vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) agonist, against UV-induced skin cell damages. We show that gremlin activated VEGFR2 and significantly inhibited UV-induced death and apoptosis of skin keratinocytes and fibroblasts. Pharmacological inhibition or shRNA-mediated knockdown of VEGFR2 almost abolished gremlin-mediated cytoprotection against UV in the skin cells. Further studies showed that gremlin activated VEGFR2 downstream NF-E2-related factor 2 (Nrf2) signaling, which appeared required for subsequent skin cell protection. Nrf2 shRNA knockdown or S40T dominant negative mutation largely inhibited gremlin-mediated skin cell protection against UV. At last, we show that gremlin dramatically inhibited UV-induced ROS production and DNA SSB formation in skin keratinocytes and fibroblasts. We conclude that gremlin protects skin cells from UV damages via activating VEGFR2-Nrf2 signaling. Gremlin could be further tested as a novel anti-UV skin protectant.

  10. Method development for thermal analyses testing on Reillex HPQ resin using the advanced reactive system screening tool (ARSST)

    SciTech Connect

    Best, D.

    2016-03-01

    Reillex™ HPQ resin was developed by Los Alamos Laboratory and Reilly Industries Inc. in an effort to increase safety and process efficiency during the recovery and purification of plutonium. Ionac™ A-641, another strong base macroporous anion exchange resin used in the nuclear industry, was known to undergo a runaway reaction in hot nitric acid solutions. Because of this, an extensive amount of thermal analyses testing on the Reillex™ HPQ resin in SRNL was performed in 1999-2001 prior to use. A report on the thermal stability qualification of the Reillex™ HPQ resin in 8M (35%) and 12M (53%) HNO3 was reported in 2000. In 2001, the reactivity of Reillex™ HPQ resin in 14.4M (64%) HNO3 was evaluated. In January of 2001, thermal stability scoping tests were performed on irradiated Reillex™ HPQ resin in 14.4M (64%) HNO3 (as a worst case scenario) and the results sent to Fauske and Associates to calculate a rupture disk size for the HB-Line resin column. A technical report by Fauske and Associates was issued in February 2001 recommending a 2.0” vent line with a rupture disk set pressure of 60 psig. This calculation was based on ARSST thermal analyses scoping tests at SRNL in which 4 grams of dried resin and 6.0 grams of 64% nitric acid in a 10 gram test cell, produced a maximum pressure rate (dP/dt) of 720 psi/min (12 psi/sec) and a maximum temperature of 250 °C. In 2015, a new batch of Reillex™ HPQ resin was manufactured by Vertellus Industries. A test sample of the resin was sent to SRNL to perform acceptance and qualification thermal stability testing using the ARSST. During these tests, method development was performed to ensure that a representative resin to acid ratios were used while running the tests in the ARSST. Fauske and Associates recommended to either use a full test cell representative of the HB-Line column or a 10 gram sample in the test cell that was representative of the ratios of resin to nitric acid in

  11. 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.

  12. Beneficial effects of a skin tolerance-tested moisturizing cream on the barrier function in experimentally-elicited irritant and allergic contact dermatitis.

    PubMed

    De Paépe, K; Hachem, J P; Vanpee, E; Goossens, A; Germaux, M A; Lachapelle, J M; Lambert, J; Matthieu, L; Roseeuw, D; Suys, E; Van Hecke, E; Rogiers, V

    2001-06-01

    In experimentally-induced irritant (ICD) and allergic (ACD) contact dermatitis, an oil-in-water (o/w) cream was applied to investigate its effects on a disturbed barrier function compared to untreated physiological barrier repair. Transepidermal water loss (TEWL) measurements were performed. Before the start of the experiments, the skin tolerance of the cream was examined, revealing the non-irritating characteristics of the ingredients and the absence of any contact allergic patch test reaction. In the ICD study, sodium lauryl sulfate (SLS) patches were applied to the forearms of young female volunteers. Consequently, it was observed that repeated cream application (14 days, 2x/day) significantly improved the TEWL of SLS-damaged skin, leading to a complete recovery on day 15. In the ACD study, disruption of skin barrier function was obtained by a nickel-mediated contact allergy patch (CAP) test. The cream was then applied 2x/day for 4 consecutive days. Assessment of TEWL clearly showed that recovery of the disrupted skin significantly improved after cream application in comparison to untreated barrier repair.

  13. Sensitive skin: an overview.

    PubMed

    Berardesca, E; Farage, M; Maibach, H

    2013-02-01

    Sensitive skin is a condition of subjective cutaneous hyper-reactivity to environmental factors. Subjects experiencing this condition report exaggerated reactions when their skin is in contact with cosmetics, soaps and sun screens, and they often report worsening after exposure to dry and cold climate. Although no sign of irritation is commonly detected, itching, burning, stinging and a tight sensation are constantly present. Generally substances that are not commonly considered irritants are involved in this abnormal response.Sensitive skin and subjective irritation are widespread but still far from being completely defined and understood. A correlation between sensitive skin and constitutional anomalies and/or other triggering factors such as occupational skin diseases or chronic exposure to irritants has been hypothesized. Recent findings suggest that higher sensitivity can be due to different mechanisms. Hyper-reactors may have a thinner stratum corneum with a reduced corneocyte area causing a higher transcutaneous penetration of water-soluble chemicals. Alterations in vanilloid receptors and changes in neuronal transmission have been described. Monitoring skin parameters such as barrier function, proclivity to irritation, corneocyte size and sensorial transmission can also be useful to identify regional differences in skin sensitivity.

  14. 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 ...

  15. 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...

  16. Comparison of the statistics of Salmonella testing of chilled broiler chicken carcasses by whole-carcass rinse and neck skin excision.

    PubMed

    Cason, J A; Cox, N A; Buhr, R J; Richardson, L J

    2010-09-01

    Whether a required Salmonella test series is passed or failed depends not only on the presence of the bacteria but also on the methods for taking samples, the methods for culturing samples, and the statistics associated with the sampling plan. The pass-fail probabilities of the 2-class attribute sampling plans used for testing chilled chicken carcasses in the United States and Europe were compared by calculation and simulation. Testing in the United States uses whole-carcass rinses (WCR), with a maximum number of 12 positives out of 51 carcasses in a test set. Those numbers were chosen so that a plant operating with a Salmonella prevalence of 20%, the national baseline result for broiler chicken carcasses, has an approximately 80% probability of passing a test set. The European Union requires taking neck skin samples of approximately 8.3 g each from 150 carcasses, with the neck skins cultured in pools of 3 and with 7 positives as the maximum passing score for a test set of 50 composite samples. For each of these sampling plans, binomial probabilities were calculated and 100,000 complete sampling sets were simulated using a random number generator in a spreadsheet. Calculations indicated that a 20% positive rate in WCR samples was approximately equivalent to an 11.42% positive rate in composite neck skin samples or a 3.96% positive rate in individual neck skin samples within a pool of 3. With 20% as the prevalence rate, 79.3% of the simulated WCR sets passed with 12 or fewer positive carcasses per set, very near the expected 80% rate. Under simulated European conditions, a Salmonella prevalence of 3.96% in individual neck skin samples yielded a passing rate of 79.1%. The 2 sampling plans thus have roughly equivalent outcomes if WCR samples have a Salmonella-positive rate of 20% and individual neck skin samples have a positive rate of 3.96%. Sampling and culturing methods must also be considered in comparing the different standards for Salmonella.

  17. Agreement between QuantiFERON®-TB Gold In-Tube and the tuberculin skin test and predictors of positive test results in Warao Amerindian pediatric tuberculosis contacts

    PubMed Central

    2014-01-01

    Background Interferon-gamma release assays have emerged as a more specific alternative to the tuberculin skin test (TST) for detection of tuberculosis (TB) infection, especially in Bacille Calmette-Guérin (BCG) vaccinated people. We determined the prevalence of Mycobacterium tuberculosis infection by TST and QuantiFERON®-TB Gold In-Tube (QFT-GIT) and assessed agreement between the two test methods and factors associated with positivity in either test in Warao Amerindian children in Venezuela. Furthermore, progression to active TB disease was evaluated for up to 12 months. Methods 163 HIV-negative childhood household contacts under 16 years of age were enrolled for TST, QFT-GIT and chest X-ray (CXR). Follow-up was performed at six and 12 months. Factors associated with TST and QFT-GIT positivity were studied using generalized estimation equations logistic regression models. Results At baseline, the proportion of TST positive children was similar to the proportion of children with a positive QFT-GIT (47% vs. 42%, p = 0.12). Overall concordance between QFT-GIT and TST was substantial (kappa 0.76, 95% CI 0.46-1.06). Previous BCG vaccination was not associated with significantly increased positivity in either test (OR 0.68, 95% CI 0.32-1.5 for TST and OR 0.51, 95% CI 0.14-1.9 for QFT-GIT). Eleven children were diagnosed with active TB at baseline. QFT-GIT had a higher sensitivity for active TB (88%, 95% CI 47-98%) than TST (55%, 95% CI 24-83%) while specificities were similar (respectively 58% and 55%). Five initially asymptomatic childhood contacts progressed to active TB disease during follow-up. Conclusion Replacement of TST by the QFT-GIT for detection of M. tuberculosis infection is not recommended in this resource-constrained setting as test results showed substantial concordance and TST positivity was not affected by previous BCG vaccination. The QFT-GIT had a higher sensitivity than the TST for the detection of TB disease. However, the value of the QFT

  18. 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.

  19. 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

  20. 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.

  1. Use of cephalosporins in patients with immediate penicillin hypersensitivity: cross-reactivity revisited.

    PubMed

    Lee, Q U

    2014-10-01

    A 10% cross-reactivity rate is commonly cited between penicillins and cephalosporins. However, this figure originated from studies in the 1960s and 1970s which included first-generation cephalosporins with similar side-chains to penicillins. Cephalosporins were frequently contaminated by trace amount of penicillins at that time. The side-chain hypothesis for beta-lactam hypersensitivity is supported by abundant scientific evidence. Newer generations of cephalosporins possess side-chains that are dissimilar to those of penicillins, leading to low cross-reactivity. In the assessment of cross-reactivity between penicillins and cephalosporins, one has to take into account the background beta-lactam hypersensitivity, which occurs in up to 10% of patients. Cross-reactivity based on skin testing or in-vitro test occurs in up to 50% and 69% of cases, respectively. Clinical reactivity and drug challenge test suggest an average cross-reactivity rate of only 4.3%. For third- and fourth-generation cephalosporins, the rate is probably less than 1%. Recent international guidelines are in keeping with a low cross-reactivity rate. Despite that, the medical community in Hong Kong remains unnecessarily skeptical. Use of cephalosporins in patients with penicillin hypersensitivity begins with detailed history and physical examination. Clinicians can choose a cephalosporin with a different side-chain. Skin test for penicillin is not predictive of cephalosporin hypersensitivity, while cephalosporin skin test is not sensitive. Drug provocation test by experienced personnel remains the best way to exclude or confirm the diagnosis of drug hypersensitivity and to find a safe alternative for future use. A personalised approach to cross-reactivity is advocated.

  2. Comparison of the QuantiFERON-TB Gold In-Tube test with the tuberculin skin test for detecting latent tuberculosis infection prior to hematopoietic stem cell transplantation.

    PubMed

    Moon, S M; Lee, S-O; Choi, S-H; Kim, Y S; Woo, J H; Yoon, D H; Suh, C; Kim, D-Y; Lee, J-H; Lee, Je-H; Lee, K-H; Kim, S-H

    2013-02-01

    A total of 244 patients including 100 (41%) autologous hematopoietic stem cell transplant (HCT) recipients and 144 (59%) allogeneic HCT recipients were enrolled over a 28-month period. During the study period, no prophylaxis for latent tuberculosis (TB) infection was administrated. Of these, 201 (82%) had Bacillus Calmette-Guérin (BCG) scars or prior histories of BCG vaccination. The tuberculin skin test (TST) and the QuantiFERON-TB Gold In-Tube (QFT-GIT) test were performed simultaneously in all 244 patients. TST indurations were ≥ 5 mm in 39 of these patients (15%), and in 25 (10%) indurations were ≥ 10 mm. In addition, 40 (16%) had positive QFT-GIT outcomes, and 34 (14%) indeterminate outcomes. If the 34 patients with indeterminate QFT-GIT results were excluded from the overall agreement analysis, the agreement between the TST results (induration size ≥ 5 mm) and the QFT-GIT results in the 210 patients with clear QFT results was poor (κ = 0.08, 95% confidence interval [CI] -0.06 to 0.24), as it was for the patients with indurations ≥ 10 mm (κ = 0.15, 95% CI -0.004 to 0.31). During follow up, 2 patients developed TB after HCT. The incidence of TB in the patients with positive QFT-GIT outcomes was 2.80 per 100 person-years (95% CI 0.07-15.81), whereas among those with positive TST (≥ 5 mm) results, it was 0 per 100 person-years (95% CI 0-8.00). However, this finding should be cautiously interpreted because of the relatively short follow up and the fact that the sample size of the study cohort did not have adequate power. In conclusion, our data show that, although the frequencies of positive outcomes in the 2 TB screening tests were similar, the overall agreement between the TST and the QFT-GIT test was poor, regardless of BCG vaccination history.

  3. Distinct reactivity of the commercially available monoclonal antibodies of D-dimer and plasma FDP testing to the molecular variants of fibrin degradation products.

    PubMed

    Madoiwa, Seiji; Kitajima, Isao; Ohmori, Tsukasa; Sakata, Yoichi; Mimuro, Jun

    2013-10-01

    Fibrin degradation products (FDP) are an important marker of coagulopathy. We assessed the reactivity of the monoclonal antibodies used in clinical laboratory testing (6 D-dimer reagents, D-dimer-1-6; 4 plasma FDP reagents, plasma FDP-1-4) to quantify FDP using in vitro-generated FDP as well as FDP in clinical samples. The monoclonal antibodies used in D-dimer-1, -2, -5, and -6 reacted poorly to the low molecular weight forms of in vitro-generated FDP. The monoclonal antibodies used in D-dimer-3 and -4 had better reactivity to the low molecular weight forms of in vitro-generated FDP. The monoclonal antibodies used in plasma FDP-2, -3, and -4 reacted well to the high and low molecular weight FDP forms, while the monoclonal antibody in plasma FDP-1 reacted poorly to the low molecular weight FDP forms. Analysis of clinical samples revealed deviations in FDP molecular weight forms in DIC samples. The reactivity of the monoclonal antibodies of laboratory FDP testing to FDP variants in clinical samples was similar to that of in vitro-generated FDP. In conclusion, the monoclonal antibodies used in clinical laboratories to detect FDP have distinct reactivity to the molecular variants of FDP generated in vitro as well as those present in clinical samples. Our findings support the consensus for the standardization of D-dimer and plasma FDP testing.

  4. An experimental test of assessment reactivity within a web-based brief alcohol intervention study for college students

    PubMed Central

    Fazzino, Tera L.; Rose, Gail L.; Helzer, John E.

    2015-01-01

    Objective Web-based brief alcohol intervention (WBI) programs have efficacy in a wide range of college students and have been widely disseminated to universities to address heavy alcohol use. In the majority of efficacy studies, web-based research assessments were conducted before the intervention. Web-based research assessments may elicit reactivity, which could inflate estimates of WBI efficacy. The current study tested whether web-based research assessments conducted in combination with a WBI had additive effects on alcohol use outcomes, compared to a WBI only. Methods Undergraduate students (n= 856) from universities in the United States and Canada participated in this online study. Eligible individuals were randomized to complete 1) research assessments + WBI or 2) WBI-only. Alcohol consumption, alcohol-related problems, and protective behaviors were assessed at one-month follow up. Results Multiple regression using 20 multiply imputed datasets indicated there were no significant differences at follow up in alcohol use, alcohol-related problems, or protective behaviors used when controlling for variables with theoretical and statistical relevance. A repeated measures analysis of covariance revealed a significant decrease in peak estimated blood alcohol concentration in both groups, but no differential effects by randomized group. There were no significant moderating effects from gender, hazardous alcohol use, or motivation to change drinking. Conclusions Web-based research assessments combined with a web-based alcohol intervention did not inflate estimates of intervention efficacy when measured within-subjects. Our findings suggest universities may be observing intervention effects similar to those cited in efficacy studies, although effectiveness trials are needed. PMID:26363306

  5. 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

  6. Skin Infections

    MedlinePlus

    ... to the touch may have yellow drainage Of cellulitis: a red, inflamed area on the skin that is tender to the touch may occur in an area of a scratch or cut redness often spreads rapidly over the skin's surface ...

  7. Skin Pigment

    MedlinePlus

    ... Diseases Take Big Slice Out of America's Health, Economy (News) Health Tip: Use Caution When Applying Hair Dye Additional ... Skin Diseases Take Big Slice Out of America's Health, Economy THURSDAY, March 2, 2017 (HealthDay News) -- Skin diseases ...

  8. Sagging Skin

    MedlinePlus

    ... Stretch Marks Sun-damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkles Treatments and Procedures Ambulatory ... Stretch Marks Sun-damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkles Treatments and Procedures Ambulatory ...

  9. 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…

  10. 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 ...

  11. Evidence of cross-reactivity between olive, ash, privet, and Russian olive tree pollen allergens.

    PubMed

    Kernerman, S M; McCullough, J; Green, J; Ownby, D R

    1992-12-01

    In a clinical investigation, 103 Michigan residents with symptoms suggestive of allergic rhinitis or asthma were skin tested with olive (Olea europaea) pollen extract. Nineteen had positive reactions. Since the olive tree is not native to nor grown in Michigan, this study was undertaken to determine whether the skin test reactivity was the result of cross-reactivity among tree pollen allergens. ELISAs were developed to measure olive, ash (Fraxinus americana), privet (Ligustrum vulgare), and Russian olive (Elaeagnus angustifolia) specific IgE antibodies. Inhibition studies were performed to determine whether pollen extracts from each of these tree species could inhibit IgE antibody binding to olive extracts. Eleven of the 19 skin test-positive patients were olive-ELISA positive, eight either were ELISA-positive to ash, seven to privet and ten to Russian olive. There were significant correlations between the ELISA results to olive and each of the other three pollens. The inhibition studies demonstrated that all three of the tree pollens were capable of inhibiting the binding of IgE to olive extract in a dose-response fashion. IgE-immunoblot studies demonstrated several proteins common to olive, ash, and privet. Twelve of the olive skin test-positive patients were contacted and 75% were exposed to one or more of the studied trees in their yards. Five patients had traveled to areas where olive trees are grown. We conclude that there is a high degree of cross-reactivity among allergens from native Michigan trees and from olive trees. This cross-reactivity is the most likely reason for skin test reactivity to olive pollen extract in Michigan.

  12. The relationship between skin maturation and electrical skin impedance.

    PubMed

    Emery, M M; Hebert, A A; Aguirre Vila-Coro, A; Prager, T C

    1991-09-01

    When performing electrophysiological testing, high electrical impedance values are sometimes found in neonates. Since excessive impedance can invalidate test results, a study was conducted to delineate the relationship between skin maturation and electrical skin impedance. This study investigated the skin impedance in 72 infants ranging from 196 to 640 days of age from conception. Regression analyses demonstrated a significant relationship between impedance and age, with the highest impedance centered around full-term gestation with values falling precipitously at time points on either side. Clinically, impedance values fall to normal levels at approximately four months following full-term gestation. Skin impedance values are low in premature infants, but rapidly increase as the age approaches that of full-term neonates. Low impedance values in premature infants are attributed to greater skin hydration which results from immature skin conditions such as 1) thinner epidermal layers particularly at the transitional and cornified layers; 2) more blood flow to the skin; and 3) higher percentage of water composition. These factors facilitate the diffusion of water vapor through the skin. As the physical barrier to skin water loss matures with gestational age, the skin impedance reaches a maximum value at full term neonatal age. After this peak, a statistically significant inverse relationship exists between electrical skin impedance and age in the first year of life. This drop in skin impedance is attributed to an increase in skin hydration as a result of the greater functional maturity of eccrine sweat glands.

  13. Effect of point of care testing for C reactive protein and training in communication skills on antibiotic use in lower respiratory tract infections: cluster randomised trial

    PubMed Central

    Butler, Christopher C; Hopstaken, Rogier M; Hood, Kerenza; Dinant, Geert-Jan

    2009-01-01

    Objective To assess the effect of general practitioner testing for C reactive protein (disease approach) and receiving training in enhanced communication skills (illness approach) on antibiotic prescribing for lower respiratory tract infection. Design Pragmatic, 2×2 factorial, cluster randomised controlled trial. Setting 20 general practices in the Netherlands. Participants 40 general practitioners from 20 practices recruited 431 patients with lower respiratory tract infection. Main outcome measures The primary outcome was antibiotic prescribing at the index consultation. Secondary outcomes were antibiotic prescribing during 28 days’ follow-up, reconsultation, clinical recovery, and patients’ satisfaction and enablement. Interventions General practitioners’ use of C reactive protein point of care testing and training in enhanced communication skills separately and combined, and usual care. Results General practitioners in the C reactive protein test group prescribed antibiotics to 31% of patients compared with 53% in the no test group (P=0.02). General practitioners trained in enhanced communication skills prescribed antibiotics to 27% of patients compared with 54% in the no training group (P<0.01). Both interventions showed a statistically significant effect on antibiotic prescribing at any point during the 28 days’ follow-up. Clinicians in the combined intervention group prescribed antibiotics to 23% of patients (interaction term was non-significant). Patients’ recovery and satisfaction were similar in all study groups. Conclusion Both general practitioners’ use of point of care testing for C reactive protein and training in enhanced communication skills significantly reduced antibiotic prescribing for lower respiratory tract infection without compromising patients’ recovery and satisfaction with care. A combination of the illness and disease focused approaches may be necessary to achieve the greatest reduction in antibiotic prescribing for this

  14. 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.

  15. Measuring sunscreen protection against solar-simulated radiation-induced structural radical damage to skin using ESR/spin trapping: development of an ex vivo test method.

    PubMed

    Haywood, Rachel; Volkov, Arsen; Andrady, Carima; Sayer, Robert

    2012-03-01

    The in vitro star system used for sunscreen UVA-testing is not an absolute measure of skin protection being a ratio of the total integrated UVA/UVB absorption. The in vivo persistent-pigment-darkening method requires human volunteers. We investigated the use of the ESR-detectable DMPO protein radical-adduct in solar-simulator-irradiated skin substitutes for sunscreen testing. Sunscreens SPF rated 20+ with UVA protection, reduced this adduct by 40-65% when applied at 2 mg/cm(2). SPF 15 Organic UVA-UVB (BMDBM-OMC) and TiO(2)-UVB filters and a novel UVA-TiO(2) filter reduced it by 21, 31 and 70% respectively. Conventional broad-spectrum sunscreens do not fully protect against protein radical-damage in skin due to possible visible-light contributions to damage or UVA-filter degradation. Anisotropic spectra of DMPO-trapped oxygen-centred radicals, proposed intermediates of lipid-oxidation, were detected in irradiated sunscreen and DMPO. Sunscreen protection might be improved by the consideration of visible-light protection and the design of filters to minimise radical leakage and lipid-oxidation.

  16. Safety of Recombinant Fusion Protein ESAT6-CFP10 as a Skin Test Reagent for Tuberculosis Diagnosis: an Open-Label, Randomized, Single-Center Phase I Clinical Trial.

    PubMed

    Li, Feng; Xu, Miao; Zhou, Lijun; Xiong, Yanqing; Xia, Lu; Fan, Xiaoyong; Gu, Jun; Pu, Jiang; Lu, Shuihua; Wang, Guozhi

    2016-09-01

    This trial was conducted to explore the safety of recombinant fusion protein ESAT6-CFP10 as a skin test reagent for the diagnosis of Mycobacterium tuberculosis infection. Twenty-four healthy adult volunteers were recruited and randomized into four groups (groups A to D) to study four increasing doses of ESAT6-CFP10. All subjects in each dose group received an intradermal injection of reagent (0.1 ml) via the Mantoux technique. Then, the vital signs of all subjects were monitored, and skin reactions around injection sites and adverse events were recorded at different detection time points after the skin test. No serious adverse events were observed in this study. A total of 3 subjects had unexpected events. One subject in group A developed subcutaneous hemorrhage 24 h after the skin test, one subject in group B was found with red spots 15 min after the skin test, and another subject in group A showed abnormity during a chest X-ray after the skin test without affecting her health. One of three adverse events (red spots) was probably related to the recombinant ESAT6-CFP10 reagent. A single dose of 1, 5, 10, or 20 μg/ml of recombinant ESAT6-CFP10 as a skin test reagent for M. tuberculosis infection diagnosis is well tolerated and safe in China. (This study has been registered at ClinicalTrials.gov under registration no. NCT01999231.).

  17. Safety of Recombinant Fusion Protein ESAT6-CFP10 as a Skin Test Reagent for Tuberculosis Diagnosis: an Open-Label, Randomized, Single-Center Phase I Clinical Trial

    PubMed Central

    Li, Feng; Xu, Miao; Zhou, Lijun; Xiong, Yanqing; Xia, Lu; Fan, Xiaoyong; Gu, Jun; Pu, Jiang

    2016-01-01

    This trial was conducted to explore the safety of recombinant fusion protein ESAT6-CFP10 as a skin test reagent for the diagnosis of Mycobacterium tuberculosis infection. Twenty-four healthy adult volunteers were recruited and randomized into four groups (groups A to D) to study four increasing doses of ESAT6-CFP10. All subjects in each dose group received an intradermal injection of reagent (0.1 ml) via the Mantoux technique. Then, the vital signs of all subjects were monitored, and skin reactions around injection sites and adverse events were recorded at different detection time points after the skin test. No serious adverse events were observed in this study. A total of 3 subjects had unexpected events. One subject in group A developed subcutaneous hemorrhage 24 h after the skin test, one subject in group B was found with red spots 15 min after the skin test, and another subject in group A showed abnormity during a chest X-ray after the skin test without affecting her health. One of three adverse events (red spots) was probably related to the recombinant ESAT6-CFP10 reagent. A single dose of 1, 5, 10, or 20 μg/ml of recombinant ESAT6-CFP10 as a skin test reagent for M. tuberculosis infection diagnosis is well tolerated and safe in China. (This study has been registered at ClinicalTrials.gov under registration no. NCT01999231.) PMID:27413070

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Fibre Diffraction Analysis of Skin Offers a Very Early and Extremely Accurate Diagnostic Test for Prostate Cancer

    DOE PAGES

    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.

  3. 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.

  4. 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.

  5. Two-Step Tuberculin Skin Testing in School-Going Adolescents with Initial 0-4 Millimeter Responses in a High Tuberculosis Prevalence Setting in South India

    PubMed Central

    Murthy, Maitreyi; Selvam, Sumithra; Jesuraj, Nelson; Bennett, Sean; Doherty, Mark; Grewal, Harleen M. S.; Vaz, Mario

    2013-01-01

    Background The utility of two-step tuberculin skin testing among adolescents in high tuberculosis prevalence settings is not well established. Objectives To determine the proportion and determinants of a 0-4 mm response to an initial standard tuberculin skin test (TST) and evaluating 'boosting' with repeat testing. Methods Adolescents between 11 and 18 years attending schools/colleges underwent a TST; those with a response of between 0–4 mm had a repeat TST 1-4 weeks later. Results Initial TST was done for 6608/6643 participants; 1257 (19%) developed a 0-4 mm response to the initial TST. Younger age and under-nutrition were more likely to be associated with a 0-4 mm response, while the presence of BCG (Bacillus Calmette Guerin) scar and higher socio-economic class were less likely to be associated with a 0-4 mm response. On repeat testing boosting was seen in 13.2% (145/1098; ≥ 6 mm over the initial test) while 4.3% showed boosting using a more conservative cutoff of a repeat TST ≥ 10 mm with an increment of at least 6 mm (47/1098). History of exposure to a tuberculosis (TB) case was associated with enhanced response. Conclusion The proportion of adolescents who demonstrated boosting on two-step TST testing in our study was relatively low. As a result repeat testing did not greatly alter the prevalence of TST positivity. However, the two-step TST helps identify individuals who can potentially boost their immune response to a second test, and thus, prevents them from being misclassified as those with newly acquired infection, or tuberculin converters. While two-step tuberculin skin testing may have a limited role in population- level TST surveys, it may be useful where serial tuberculin testing needs to be performed to distinguish those who show an enhanced response or boosters from those who indeed have a new infection, or converters. PMID:24039716

  6. Limited influence of aspirin intake on mast cell activation in patients with food-dependent exercise-induced anaphylaxis: comparison using skin prick and histamine release tests.

    PubMed

    Fukunaga, Atsushi; Shimizu, Hideki; Tanaka, Mami; Kikuzawa, Ayuko; Tsujimoto, Mariko; Sekimukai, Akiko; Yamashita, Junji; Horikawa, Tatsuya; Nishigori, Chikako

    2012-09-01

    Food-dependent exercise-induced anaphylaxis (FDEIA) is a severe systemic syndrome induced by physical exercise after ingesting causative food. Aspirin is a well-known trigger for anaphylaxis in patients with FDEIA. Possible me